i n t e r n a t i o n a l journal o f hydrogen energy , 2017
In this study, we tested four algal species (Synechocystis sp. PCC 6803 and three novel algal
spe... more In this study, we tested four algal species (Synechocystis sp. PCC 6803 and three novel algal species isolated from Egyptian paddy rice soil, having high 16S rRNA gene sequence identity to Nostoc spongiaeforme, Parachlorella kessleri SAG 211-11 and Nostoc sp. PCC 7524) under aerobic, anaerobic and 3% CO2-supplemented anaerobic condition. Significant changes in photohydrogen production, morphology, chlorophyll a and protein content/ pattern were observed in all species, when grown in these different conditions. H2 production was higher in anaerobic condition in all species with the highest H2 production rate of 4 mmol H2 mg Chla1 h1 at 24 h in Synechocystis sp. In contrast, Chla content and protein content decreased (%) in N. spongiaeforme, (29%, 58%), P. kessleri (47%, 7%) and Nostoc sp. (59%, 65%).The anaerobic condition with 3% CO2 stimulated early production of H2 in all species except Synechocystis sp. Our results compared all selected algal species under different growth conditions for the screening of a superior H2-producing algal species that can help to address engineering challenges in the field of large-scale H2 photoproduction by microalgae.
The present study is a trial to cultivate three different cyanobacterial strains (Anabaena laxa, ... more The present study is a trial to cultivate three different cyanobacterial strains (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) under four different growth conditions using BG11 0 growth medium. These conditions were represented by static glucose medium with glucose (1%, w/v), aerated medium (aerated by bubbling technique depending on atmospheric CO 2 normally existed in air with a concentration of 0.03%), growth medium enriched with molasses of sugar cane (0.7%, v/v) and aerated growth medium enriched with glucose (1%, w/v). A. laxa, A. fertilissima and N. muscorum exhibited high biomass production under mixotrophic growth condition rather than aerated autotrophic condition. Whereas, static glucose medium enhanced the growth of A. laxa, A. fertilissima and N. muscorum significantly with dry weight yield of 3.6, 3.1 and 5.2 g L-1 , respectively. Moreover, glucose enhanced lipid content for both A. laxa and N. muscorum to produce 293.9 and 253.5 ìg g-1 fresh wt., respectively. While A. fertilissima exhibited the highest lipid content under aerated enriched glucose medium (307.6 ìg g-1 fresh wt.). Static glucose medium supported the lipid synthesis rate of N. muscorum to record 6.3 folds, as compared to the control, after 10 days of treatment. While A. fertilissima exhibited its highest lipid synthesis rate under aerated enriched glucose condition after 2 days. Ten fatty acids were detected for all the investigated cyanobacterial strains with different percentages, under static glucose medium (1%, w/v) during the stationary phase. Half of them were saturated fatty acids and the others were two mono-unsaturated and three poly-unsaturated fatty acids. Myristic, palmitoleic and arachidonic acids were the most abundant among all the tested isolates.
Radiation hazards are considered as one of the most serious challenges that frighteningly threate... more Radiation hazards are considered as one of the most serious challenges that frighteningly threaten our lives. This study aimed to evaluate the antioxidant properties of aqueous and ethanolic extracts of the green alga Ulva lactuca against the different genotoxic and biochemical damage induced by γ-irradiation in rats. The experimental model was divided into 4 groups: group I "control" included the non-irradiated rats, group II "Irradiated group" included rats exposed to 4 Gy(137 Cs) whole body γ-irradiation, group III composed of rats treated with an aqueous extract of U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation, and finally group IV included rats treated with the ethanolic extract U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation. The results revealed that these algal extracts noticeably eliminated the harmful effects of oxidative stress induced by exposure to γ-irradiation through decreasing the produced levels of H 2 O 2 in hepatic tissue. Furthermore, they decreased the incidence of micronucleated PCE in bone marrow cells and apoptotic DNA damage. According to the apoptotic gene expressions, the ethanolic extract of U. lactuca appears to be more efficient in down-regulations of apoptotic genes Bax and Caspase-3 than the aqueous one. Total phenolics, flavonoids and sulphated polysaccharides, well-known in order Ulvales, are thought to be the main drivers responsible for this potent antioxidant defense mechanism. The widely-distributed green alga U. lactuca seems to be a promising antioxidant and anti-apoptotic tool to overcome lethal effects of γ-irradiation.
Iron overload is induced as a result of a lot of disorders, particularly in thalassemia major, an... more Iron overload is induced as a result of a lot of disorders, particularly in thalassemia major, and is considered the main cause of mortality in spite of the recently-achieved advances in chelation therapy. The main aim of the present study was to investigate the in vivo antioxidant and Fe-chelating characteristics of both aqueous and ethanolic extracts of the marine green macroalga Caulerpa racemosa (Chlorophyta) to clearly assess its possible applications in Fe-chelating therapy, and to reduce iron-related complications for the Improvement of patients' lives. Forty male albino rats were randomly split into four equal groups: The first group was the control; the second one represented the iron overload group (ID); the third group was treated with the iron overload and an aqueous extract of C. racemosa; and the fourth group was composed of the iron overload and C. racemosa ethanolic extract. Rats were received six doses of iron dextran (12.5 mg/100 gm body weight (B.W.) by intraperitoneal injections (IP) and administrated C. racemosa (200 mg/kg B.W.) as one daily IP until the end of the experiment. The levels of iron depositions in liver, heart and brain were significantly increased in the ID treatment group compared to the control. Serum ferritin, total iron binding capacity (TIBC), unsaturated iron binding capacity (UIBC) and transferrin were also highly increased in the ID treatment group. Nevertheless, these iron profiles were significantly decreased in the ID + C. racemosa treatment groups (both the aqueous and algal extracts) compared to the ID group only. Moreover, C. racemosa extracts distinctly down-modulated iron overload causing dramatic increases in serum aspartate ami-notransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK) and lactate dehydrogenase (LDH), which were significantly increased in the ID group compared to the control. This study showed that the treatments with C. racemosa extracts effectively ameliorated the increased malondialdehyde (MDA) and nitric oxide (NO). A significant decrease in antioxidant enzyme activities such superoxide dismutase (SOD), glutathione (GSH), glutathione peroxi-dase (Gpx) and catalase (CAT) activities were only observed in the ID group compared to the control. However, these enzymes were significantly increased in the C. racemosa-treated groups. No toxic effects were distinctly detected in rats treated with the applied aqueous and ethanolic C. racemosa extracts and this obaservation was confirmed by the histopathological studies. In conclusion, this study confirms the in vivo evidence that C. racemosa administration , especially the ethanolic extract, can highly improve the antioxidant defense systems against ID-induced hepatic, cardiac and neuro-oxidative stresses in rats. These protective characteristics of C. racemosa might be attributed to its remarkable antioxidant (total phenolics, total flavonoids, DPPH and ABTS radical scavenging, and reducing power) and Fe-chelation characteristics.
The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Ana... more The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Anabanea fertilissima and Nostoc muscorum was evaluated in invitro assay as a biopesticides against 2 nd and 4 th instars of Agrotis ipsilon. Larvae were fed on leaf discs painted with the algal solution for 24h. The 2 nd instar larvae were more susceptible than the 4 th ones to the four tested algal treatments. N. muscorum treatment was the most toxic one against the 2 nd and 4 th larval instars. Where, its LC 50 values were 45 and 150 mg/ml, respectively while, A. fertilissima was the least one, its LC 50 values were 250 and 660 mg/ ml, respectively. All the treated larvae were susceptible to four tested algal treatments and its resistance varied according to the larval instars and tested alga. Marked decrease in pupation for both 2 nd and /or 4 th instar by the four algal treatments, whereas, the 2 nd instar treated with N. muscorum alga exhibited the most suppressive decrease to 44%, as compared to control (97%). Significant reduction for pupal weight, where, 4 th instar treated with A. flos aquae alga recorded the highest pupal weight decrease to average 290mg, as compared to 484mg of control. Besides prolonging pupal duration where, treatment for both instar with A. flos aquae and A. laxa algae induced the longest period and increased the pupal malformation percent where, 4 th instar treated with N. muscorum and A. flos aquae algae induced noticeable percent reached to21.3 and20% and increased adult malformation to30 and20% respectively, as respect to control. However, the larval treatment of 2 nd instar with N. muscorum and A. fertilissima algae had the strongest effect in larval duration increase to average25 and 25.8day as compared to20.4day of control. In addition, the larval treatment of 4 th instar with the four algae decreased the adult fecundity and fertility. Moreover, N. muscorum and A. flos aquae algae inhibited the adult fecundity and eggs fertility to zero, as compared to505eggs/female of control. Marked declining of adult longevity with N. muscorum, A. flos aquae and A.laxa to average 7day, as compared to11day of control. Also, the treatment with the three algae disorder the sex ratio of males and females, as compared to that of control. While the larval treatment with A. fertilissima alga didn't affect the pupal malformation, eggs fertility, adult longevity and sex ratio.
Australian Journal of Basic and Applied Sciences, 2016
The present study aimed to prepare silver and silver chloride nanoparticles (Ag and AgCl-NPs) us... more The present study aimed to prepare silver and silver chloride nanoparticles (Ag and AgCl-NPs) using the crude aqueous extract of the green microalga Parachlorella kessleri SAG 211-11, study their physicochemical properties and evaluation of their nematicidal proficiency against the 2 nd larval instars and egg hatchability of Meloidogyne incognita. This process showed a rapid formation of highly stable Ag and AgCl-NPs. UV-Vis absorption spectrum revealed the biosynthesis of Ag and AgCl-NPs with a maximum absorbance at 414 nm. TEM analysis showed formation of spherical Ag and AgCl NPs with an average size of 10.3 to 47 nm. Crystalline nature of the synthesized nanoparticles are also confirmed by their remarkable peaks in the XRD patterns corresponding to 111, 200, 220 and 311 planes for Ag-NPs and 111, 200, 220, 311, 222, 400 and 331 planes for AgCl-NPs. The synthesized Ag/AgCl-NPs exhibited magnetic properties with-33.5 mv surface charge. Fourier Transform Infra Red spectroscopy (FTIR) of purified nanoparticle fractions suggested that proteins are the main molecular entities involved in Ag and AgCl-NP formation and stabilization. The biosynthesized Ag/AgCl-NPs exhibited significant reduction of eggs hatchability at low concentrations (10-20% v/v) as well as, significant increase in larval mortality over the chemical nematicide at concentrations (50-500 µl/L). LC50 values were 200 and ˂50 µl/L at 24h and 48h of incubation respectively; 500µl/L completely inhibited larval growth by 100%. The presented study highlights the possibility of large-scale production of Ag/AgCl-NPs by using P. kessleri due to its simplicity, accessibility and effectiveness and can be highly recommended as a promising tool for biological control of root knot nematode (M. incognita).
Australian Journal of Basic and Applied Sciences, 2017
Marine macroalgae are rich source of structurally novel and biologically active metabolites that... more Marine macroalgae are rich source of structurally novel and biologically active metabolites that could be used in biological control of some plant diseases. In this study, we evaluated the antimicrobial activities of crude methanolic extracts of three brown macroalgal spices; Sargassum latifolium. Hydroclathrus clathratus and Padina gymnospora, collected from Red Sea, Hurghada coastline, Egypt, against four soil borne plant pathogenic microbes, bacteria; Ralstonia solanacearum and Pectobacterium carotovora, fungi; Fusarium solani, Rhizoctonia solani. Minimal inhibition concentration (MIC) was 1.25 mg/disc for three algal species except, H. clathratus had no effect against F. solani and R. solani. The methanolic extract of P. gymnospora recorded the highest inhibition zones (18.3, 16.3 mm) against R. solanacearum and P. carotovora at 5 mg/disc and (24, 21.7 mm) against F. solani and R. solani at 7 mg/disc, respectively. Phyto-chemical analyses of fatty acids, saccharides and phenolic compounds revealed that, P. gymnospora and S. latifolium were characterized by the highest proportion of total saturated fatty acids with (58.33 %, 42.78). In contrast, H. clathratus showed the highest content of unsaturated fatty acids by 58.21 %. Palmitic acid (C16:0) was the most abundant saturated fatty acid in S. latifolium, H. clathratus and P. gymnospora extracts by (29.5, 21.4 and 36.4 %), respectively. Interestingly, arachidonic acid (all cis 5,8,11,14-C20:4) was only detected in P. gymnospora methanol extract by 2 %. Stachyose represented the highest saccharide fraction in S. latifolium and P. gymnospora by (67.3 and 56.9 %), respectively; while, Glucouronic recorded the highest saccharide fraction in H. clathratus by (42 %). P. gymnospora had the highest content of chlorogenic, P-OH-benzoic and e-vanillic with (25.0, 40 and 567.2 ppm) respectively, compared to S. latifolium and H. clathratus. In addition, in vivo application of the powder of P. gymnospora, S. latifolium and H. clathratus, as soil amendment, in Solanum melongena L. (eggplant) pot experiment significantly decreased the percentage of root rotting in F. solani infected-soil by 83, 56 and 27 %, respectively. Moreover, P. gymnospora enhanced growth performance of eggplant in term of shoot length and plant fresh weight in the infected soil. Moreover, soil-free pathogen treated with P. gymnospora and S. latifolium powder showed significant increase in root length compared to control as well as increased fruit fresh weight by P. gymnospora powder. The considerable antimicrobial/biostimulant activities of P. gymnospora are due to its phyto-chemicals composition. This makes it feasible for biological control of some plant diseases and biosimulant agent for plant growth.
Silver chloride nanoparticles (AgCl-NPs) is a powerful antimicrobial agent. A possible source of ... more Silver chloride nanoparticles (AgCl-NPs) is a powerful antimicrobial agent. A possible source of biological material for the green biosynthesis of AgCl-NPs was represented by microalgae. In this study rapid biosynthesis of stable AgCl-NPs was achieved by using ethanol extract of cyanobacterium, Anabaena variabilis v. Kashiensis. The results were verified using UV-Vis spectroscopy, High Resolution Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD). Bioreduction of Ag + ions showed a gradual change in the colour of the extract to brown. Peaks of UV-Vis spectra showed surface plasmon resonance (SPR) at (409 nm). TEM micrograph analyses confirmed formation of homogenous spherical AgCl-NPs, ranged in size from (12-20 nm). The crystalline nature of the synthesized AgCl-NPs was assigned by their remarkable peaks in the XRD patterns corresponding to (111, 200, 220, 311, 222, 400 and 420) planes. Fourier Transform Infrared Spectroscopy (FTIR) of purified nanoparticle fractions suggested that proteins were the main molecular entities involved in AgCl-NPs formation and stabilization. This study provides a new report for the cyanobacterial species, Anabaena variabilis that, could serve as good, cheap substrate for biogenic of homogenous spherical AgCl-NPs. [Seham M. Hamed, Manal M. Abdel-Alim, Neveen Abdel-Raouf, Ibraheem B.M. Ibraheem. Biosynthesis of silver chloride nanoparticles using the cyanobacterium Anabaena variabilis. Life Sci J 2017;14(6):25-30].
Beni-Suef University Journal of Basic and Applied Sciences, 2018
Marine macroalgae are plant-like organisms with simple internal structures that generally live in... more Marine macroalgae are plant-like organisms with simple internal structures that generally live in coastal areas. They mainly include different communities of red, brown and green macroalgae. Marine macroalgae commonly occupy intertidal and sublittoral-to-littoral zones on rocks and other hard substrata. They are considered to be an excellent natural biosource in different aspects of agricultural fields. They have great proficiency in improving soil physical and chemical properties. Marine macroalgae are also characterized by producing a large array of biologically active biocidal substances against plant-infecting pathogens. Unfortunately, most available literatures on marine macroalgae and their derivatives mainly focused on their pharmaceutical applications but their potential utilization in sustainable agriculture development is still often regarded as a secondary goal. However, a relatively considerable dataset on marine macroalgae showed that they could play a major role in plant protection and improvement. This review summarizes different aspects of potential macroalgal applications in agriculture. Commercial production and exploitation of specific compounds with interesting biotechnological importance from marine macroalgae including microbicides, nematicides, insecticides, biofertilizers, biostimulators and soil conditioners are highlighted and discussed in detail. Bioactive compounds like fatty acids (in particular polyunsaturated fatty acids (PUFAs), proteins (amino acids), bioflavonoids, sulfated polysaccharides, carotenoids, polyphenols and carbohydrates are considered to have bactericidal, antiviral and fungicidal effects against some plant-infecting pathogens. These biocontrol agents provide multiple benefits and act as useful pointers for improving cultivation practices in diverse habitats. Marine macroalgae can be generally considered as promising multifunctional bioinoculants and ecofriendly environmental tools in recent trends of organic farming.
The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Ana... more The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Anabanea fertilissima and Nostoc muscorum was evaluated in invitro assay as a biopesticides against 2 nd and 4 th instars of Agrotis ipsilon. Larvae were fed on leaf discs painted with the algal solution for 24h. The 2 nd instar larvae were more susceptible than the 4 th ones to the four tested algal treatments. N. muscorum treatment was the most toxic one against the 2 nd and 4 th larval instars. Where, its LC 50 values were 45 and 150 mg/ml, respectively while, A. fertilissima was the least one, its LC 50 values were 250 and 660 mg/ ml, respectively. All the treated larvae were susceptible to four tested algal treatments and its resistance varied according to the larval instars and tested alga. Marked decrease in pupation for both 2 nd and /or 4 th instar by the four algal treatments, whereas, the 2 nd instar treated with N. muscorum alga exhibited the most suppressive decrease to 44%, as compared to control (97%). Significant reduction for pupal weight, where, 4 th instar treated with A. flos aquae alga recorded the highest pupal weight decrease to average 290mg, as compared to 484mg of control. Besides prolonging pupal duration where, treatment for both instar with A. flos aquae and A. laxa algae induced the longest period and increased the pupal malformation percent where, 4 th instar treated with N. muscorum and A. flos aquae algae induced noticeable percent reached to21.3 and20% and increased adult malformation to30 and20% respectively, as respect to control. However, the larval treatment of 2 nd instar with N. muscorum and A. fertilissima algae had the strongest effect in larval duration increase to average25 and 25.8day as compared to20.4day of control. In addition, the larval treatment of 4 th instar with the four algae decreased the adult fecundity and fertility. Moreover, N. muscorum and A. flos aquae algae inhibited the adult fecundity and eggs fertility to zero, as compared to505eggs/female of control. Marked declining of adult longevity with N. muscorum, A. flos aquae and A.laxa to average 7day, as compared to11day of control. Also, the treatment with the three algae disorder the sex ratio of males and females, as compared to that of control. While the larval treatment with A. fertilissima alga didn't affect the pupal malformation, eggs fertility, adult longevity and sex ratio.
Information available on the utilization of algae and cyanobacteria, with manifold potential appl... more Information available on the utilization of algae and cyanobacteria, with manifold potential applications in agriculture and biotechnology, for commercial biopesticide production is still scarce. We used the algal/cyanobacterial extract-larval contact method to assay in vitro against different developmental life cycle stages (the 2nd and 4th instars) of the cotton leafworm Spodoptera littoralis crude ethanolic extracts of five different algal and cyanobacterial species: Chara vulgaris (stonewort), Parachlorella kessleri, Ulva intestinalis, Cladophora glomerata (green algae), and the heterocytous cyanobacterium Nostoc carneum. All the algal and cyanobacterial treatments showed insecticidal activities against larvae of S. littoralis, with 2nd larval instars being more susceptible. In general, P. kessleri and N. carneum exhibited the highest insecticidal toxic effects while the stonewort C. vulgaris showed the lowest insecticidal activity. Effects of these algal and cyanobacterial treatments on larval duration, % pupal formation, pupal duration and weight, % moth emergence, adults’ fecundity and longevity, eggs’ hatching, sex ratios, and larval-pupal-moth malformations were discussed. Gas chromatography-mass spectrometry (GC-MS) analyses of the crude algal and cyanobacterial extracts revealed 29 compounds, mainly containing an array of saturated and unsaturated fatty acids, some essential oils, and terpene compounds like phytol. Insecticidal activities of the algal and cyanobacterial specimens can be attributed to the synergistic effects of the abovementioned phytochemical constituents, particularly fatty acids such as the polyunsaturated ω-6 linoleic, palmitic, oleic, myristic, α-linolenic, and 7, 10-hexadecadienoic acids. The coccoid green alga P. kessleri and the cyanobacterium N. carneum can thus be recommended as ecofriendly biopesticides for the integrated pest management of the cotton leafworm and other agricultural pests.
Crude extract of Anabaena flos aquae alga cyanobacterial strains was evaluated in laboratory as a... more Crude extract of Anabaena flos aquae alga cyanobacterial strains was evaluated in laboratory as a biocomponents against 2nd and 4th instars of the cotton leaf worm, Spodoptera littoralis (Boisd.). Larvae were treated with the algal extract via contact and feeding methods. Effect of the algal extract varied according to the larval instars and the method of application. Contact algal treatment was more effective than the feeding treatment. The 2nd larval instar was more susceptible than the 4th one. LC50 value for the 2nd larval instar of S. littoralis was 12.5 ppm compared with 25 ppm for the 4th instar. In case of feeding treatment, they were 50 and 100 ppm for the 2nd and 4th instars, respectively. LC50 value of the contact method induced highly significant increase of the larval and pupal durations, adults’ emergence decrease to 59.5%, compared with 99.7% for the untreated control. It induced the highest percentage of pupation (43%) and adults’ malformation reached 25%. Adults emerged from the treated 4th larval instar recorded high reduction in numbers of deposited egg (reached 28.3 eggs/ female) compared with (475 eggs/ female) for the control. Eggs fertility was decreased to 78.4% compared with 100% for the control. Highly significant reduction in the percentage of pupation was observed. Also, LC50 values obtained from the contact or feeding treatments on the 4th larval instar reduced the longevity of the resulted adults and percentage of the adults’ emergence. Disorder for the sex ratio was observed.
Variation in the traditional growth medium conditions to enhance the production of lipids, carboh... more Variation in the traditional growth medium conditions to enhance the production of lipids, carbohydrates, protein and the free amino acids content of three cyanobacterial species. Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.).
i n t e r n a t i o n a l journal o f hydrogen energy , 2017
In this study, we tested four algal species (Synechocystis sp. PCC 6803 and three novel algal
spe... more In this study, we tested four algal species (Synechocystis sp. PCC 6803 and three novel algal species isolated from Egyptian paddy rice soil, having high 16S rRNA gene sequence identity to Nostoc spongiaeforme, Parachlorella kessleri SAG 211-11 and Nostoc sp. PCC 7524) under aerobic, anaerobic and 3% CO2-supplemented anaerobic condition. Significant changes in photohydrogen production, morphology, chlorophyll a and protein content/ pattern were observed in all species, when grown in these different conditions. H2 production was higher in anaerobic condition in all species with the highest H2 production rate of 4 mmol H2 mg Chla1 h1 at 24 h in Synechocystis sp. In contrast, Chla content and protein content decreased (%) in N. spongiaeforme, (29%, 58%), P. kessleri (47%, 7%) and Nostoc sp. (59%, 65%).The anaerobic condition with 3% CO2 stimulated early production of H2 in all species except Synechocystis sp. Our results compared all selected algal species under different growth conditions for the screening of a superior H2-producing algal species that can help to address engineering challenges in the field of large-scale H2 photoproduction by microalgae.
The present study is a trial to cultivate three different cyanobacterial strains (Anabaena laxa, ... more The present study is a trial to cultivate three different cyanobacterial strains (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) under four different growth conditions using BG11 0 growth medium. These conditions were represented by static glucose medium with glucose (1%, w/v), aerated medium (aerated by bubbling technique depending on atmospheric CO 2 normally existed in air with a concentration of 0.03%), growth medium enriched with molasses of sugar cane (0.7%, v/v) and aerated growth medium enriched with glucose (1%, w/v). A. laxa, A. fertilissima and N. muscorum exhibited high biomass production under mixotrophic growth condition rather than aerated autotrophic condition. Whereas, static glucose medium enhanced the growth of A. laxa, A. fertilissima and N. muscorum significantly with dry weight yield of 3.6, 3.1 and 5.2 g L-1 , respectively. Moreover, glucose enhanced lipid content for both A. laxa and N. muscorum to produce 293.9 and 253.5 ìg g-1 fresh wt., respectively. While A. fertilissima exhibited the highest lipid content under aerated enriched glucose medium (307.6 ìg g-1 fresh wt.). Static glucose medium supported the lipid synthesis rate of N. muscorum to record 6.3 folds, as compared to the control, after 10 days of treatment. While A. fertilissima exhibited its highest lipid synthesis rate under aerated enriched glucose condition after 2 days. Ten fatty acids were detected for all the investigated cyanobacterial strains with different percentages, under static glucose medium (1%, w/v) during the stationary phase. Half of them were saturated fatty acids and the others were two mono-unsaturated and three poly-unsaturated fatty acids. Myristic, palmitoleic and arachidonic acids were the most abundant among all the tested isolates.
Radiation hazards are considered as one of the most serious challenges that frighteningly threate... more Radiation hazards are considered as one of the most serious challenges that frighteningly threaten our lives. This study aimed to evaluate the antioxidant properties of aqueous and ethanolic extracts of the green alga Ulva lactuca against the different genotoxic and biochemical damage induced by γ-irradiation in rats. The experimental model was divided into 4 groups: group I "control" included the non-irradiated rats, group II "Irradiated group" included rats exposed to 4 Gy(137 Cs) whole body γ-irradiation, group III composed of rats treated with an aqueous extract of U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation, and finally group IV included rats treated with the ethanolic extract U. lactuca 100 mg/kg body weight for 15 days before 4 Gy of γ-irradiation. The results revealed that these algal extracts noticeably eliminated the harmful effects of oxidative stress induced by exposure to γ-irradiation through decreasing the produced levels of H 2 O 2 in hepatic tissue. Furthermore, they decreased the incidence of micronucleated PCE in bone marrow cells and apoptotic DNA damage. According to the apoptotic gene expressions, the ethanolic extract of U. lactuca appears to be more efficient in down-regulations of apoptotic genes Bax and Caspase-3 than the aqueous one. Total phenolics, flavonoids and sulphated polysaccharides, well-known in order Ulvales, are thought to be the main drivers responsible for this potent antioxidant defense mechanism. The widely-distributed green alga U. lactuca seems to be a promising antioxidant and anti-apoptotic tool to overcome lethal effects of γ-irradiation.
Iron overload is induced as a result of a lot of disorders, particularly in thalassemia major, an... more Iron overload is induced as a result of a lot of disorders, particularly in thalassemia major, and is considered the main cause of mortality in spite of the recently-achieved advances in chelation therapy. The main aim of the present study was to investigate the in vivo antioxidant and Fe-chelating characteristics of both aqueous and ethanolic extracts of the marine green macroalga Caulerpa racemosa (Chlorophyta) to clearly assess its possible applications in Fe-chelating therapy, and to reduce iron-related complications for the Improvement of patients' lives. Forty male albino rats were randomly split into four equal groups: The first group was the control; the second one represented the iron overload group (ID); the third group was treated with the iron overload and an aqueous extract of C. racemosa; and the fourth group was composed of the iron overload and C. racemosa ethanolic extract. Rats were received six doses of iron dextran (12.5 mg/100 gm body weight (B.W.) by intraperitoneal injections (IP) and administrated C. racemosa (200 mg/kg B.W.) as one daily IP until the end of the experiment. The levels of iron depositions in liver, heart and brain were significantly increased in the ID treatment group compared to the control. Serum ferritin, total iron binding capacity (TIBC), unsaturated iron binding capacity (UIBC) and transferrin were also highly increased in the ID treatment group. Nevertheless, these iron profiles were significantly decreased in the ID + C. racemosa treatment groups (both the aqueous and algal extracts) compared to the ID group only. Moreover, C. racemosa extracts distinctly down-modulated iron overload causing dramatic increases in serum aspartate ami-notransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK) and lactate dehydrogenase (LDH), which were significantly increased in the ID group compared to the control. This study showed that the treatments with C. racemosa extracts effectively ameliorated the increased malondialdehyde (MDA) and nitric oxide (NO). A significant decrease in antioxidant enzyme activities such superoxide dismutase (SOD), glutathione (GSH), glutathione peroxi-dase (Gpx) and catalase (CAT) activities were only observed in the ID group compared to the control. However, these enzymes were significantly increased in the C. racemosa-treated groups. No toxic effects were distinctly detected in rats treated with the applied aqueous and ethanolic C. racemosa extracts and this obaservation was confirmed by the histopathological studies. In conclusion, this study confirms the in vivo evidence that C. racemosa administration , especially the ethanolic extract, can highly improve the antioxidant defense systems against ID-induced hepatic, cardiac and neuro-oxidative stresses in rats. These protective characteristics of C. racemosa might be attributed to its remarkable antioxidant (total phenolics, total flavonoids, DPPH and ABTS radical scavenging, and reducing power) and Fe-chelation characteristics.
The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Ana... more The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Anabanea fertilissima and Nostoc muscorum was evaluated in invitro assay as a biopesticides against 2 nd and 4 th instars of Agrotis ipsilon. Larvae were fed on leaf discs painted with the algal solution for 24h. The 2 nd instar larvae were more susceptible than the 4 th ones to the four tested algal treatments. N. muscorum treatment was the most toxic one against the 2 nd and 4 th larval instars. Where, its LC 50 values were 45 and 150 mg/ml, respectively while, A. fertilissima was the least one, its LC 50 values were 250 and 660 mg/ ml, respectively. All the treated larvae were susceptible to four tested algal treatments and its resistance varied according to the larval instars and tested alga. Marked decrease in pupation for both 2 nd and /or 4 th instar by the four algal treatments, whereas, the 2 nd instar treated with N. muscorum alga exhibited the most suppressive decrease to 44%, as compared to control (97%). Significant reduction for pupal weight, where, 4 th instar treated with A. flos aquae alga recorded the highest pupal weight decrease to average 290mg, as compared to 484mg of control. Besides prolonging pupal duration where, treatment for both instar with A. flos aquae and A. laxa algae induced the longest period and increased the pupal malformation percent where, 4 th instar treated with N. muscorum and A. flos aquae algae induced noticeable percent reached to21.3 and20% and increased adult malformation to30 and20% respectively, as respect to control. However, the larval treatment of 2 nd instar with N. muscorum and A. fertilissima algae had the strongest effect in larval duration increase to average25 and 25.8day as compared to20.4day of control. In addition, the larval treatment of 4 th instar with the four algae decreased the adult fecundity and fertility. Moreover, N. muscorum and A. flos aquae algae inhibited the adult fecundity and eggs fertility to zero, as compared to505eggs/female of control. Marked declining of adult longevity with N. muscorum, A. flos aquae and A.laxa to average 7day, as compared to11day of control. Also, the treatment with the three algae disorder the sex ratio of males and females, as compared to that of control. While the larval treatment with A. fertilissima alga didn't affect the pupal malformation, eggs fertility, adult longevity and sex ratio.
Australian Journal of Basic and Applied Sciences, 2016
The present study aimed to prepare silver and silver chloride nanoparticles (Ag and AgCl-NPs) us... more The present study aimed to prepare silver and silver chloride nanoparticles (Ag and AgCl-NPs) using the crude aqueous extract of the green microalga Parachlorella kessleri SAG 211-11, study their physicochemical properties and evaluation of their nematicidal proficiency against the 2 nd larval instars and egg hatchability of Meloidogyne incognita. This process showed a rapid formation of highly stable Ag and AgCl-NPs. UV-Vis absorption spectrum revealed the biosynthesis of Ag and AgCl-NPs with a maximum absorbance at 414 nm. TEM analysis showed formation of spherical Ag and AgCl NPs with an average size of 10.3 to 47 nm. Crystalline nature of the synthesized nanoparticles are also confirmed by their remarkable peaks in the XRD patterns corresponding to 111, 200, 220 and 311 planes for Ag-NPs and 111, 200, 220, 311, 222, 400 and 331 planes for AgCl-NPs. The synthesized Ag/AgCl-NPs exhibited magnetic properties with-33.5 mv surface charge. Fourier Transform Infra Red spectroscopy (FTIR) of purified nanoparticle fractions suggested that proteins are the main molecular entities involved in Ag and AgCl-NP formation and stabilization. The biosynthesized Ag/AgCl-NPs exhibited significant reduction of eggs hatchability at low concentrations (10-20% v/v) as well as, significant increase in larval mortality over the chemical nematicide at concentrations (50-500 µl/L). LC50 values were 200 and ˂50 µl/L at 24h and 48h of incubation respectively; 500µl/L completely inhibited larval growth by 100%. The presented study highlights the possibility of large-scale production of Ag/AgCl-NPs by using P. kessleri due to its simplicity, accessibility and effectiveness and can be highly recommended as a promising tool for biological control of root knot nematode (M. incognita).
Australian Journal of Basic and Applied Sciences, 2017
Marine macroalgae are rich source of structurally novel and biologically active metabolites that... more Marine macroalgae are rich source of structurally novel and biologically active metabolites that could be used in biological control of some plant diseases. In this study, we evaluated the antimicrobial activities of crude methanolic extracts of three brown macroalgal spices; Sargassum latifolium. Hydroclathrus clathratus and Padina gymnospora, collected from Red Sea, Hurghada coastline, Egypt, against four soil borne plant pathogenic microbes, bacteria; Ralstonia solanacearum and Pectobacterium carotovora, fungi; Fusarium solani, Rhizoctonia solani. Minimal inhibition concentration (MIC) was 1.25 mg/disc for three algal species except, H. clathratus had no effect against F. solani and R. solani. The methanolic extract of P. gymnospora recorded the highest inhibition zones (18.3, 16.3 mm) against R. solanacearum and P. carotovora at 5 mg/disc and (24, 21.7 mm) against F. solani and R. solani at 7 mg/disc, respectively. Phyto-chemical analyses of fatty acids, saccharides and phenolic compounds revealed that, P. gymnospora and S. latifolium were characterized by the highest proportion of total saturated fatty acids with (58.33 %, 42.78). In contrast, H. clathratus showed the highest content of unsaturated fatty acids by 58.21 %. Palmitic acid (C16:0) was the most abundant saturated fatty acid in S. latifolium, H. clathratus and P. gymnospora extracts by (29.5, 21.4 and 36.4 %), respectively. Interestingly, arachidonic acid (all cis 5,8,11,14-C20:4) was only detected in P. gymnospora methanol extract by 2 %. Stachyose represented the highest saccharide fraction in S. latifolium and P. gymnospora by (67.3 and 56.9 %), respectively; while, Glucouronic recorded the highest saccharide fraction in H. clathratus by (42 %). P. gymnospora had the highest content of chlorogenic, P-OH-benzoic and e-vanillic with (25.0, 40 and 567.2 ppm) respectively, compared to S. latifolium and H. clathratus. In addition, in vivo application of the powder of P. gymnospora, S. latifolium and H. clathratus, as soil amendment, in Solanum melongena L. (eggplant) pot experiment significantly decreased the percentage of root rotting in F. solani infected-soil by 83, 56 and 27 %, respectively. Moreover, P. gymnospora enhanced growth performance of eggplant in term of shoot length and plant fresh weight in the infected soil. Moreover, soil-free pathogen treated with P. gymnospora and S. latifolium powder showed significant increase in root length compared to control as well as increased fruit fresh weight by P. gymnospora powder. The considerable antimicrobial/biostimulant activities of P. gymnospora are due to its phyto-chemicals composition. This makes it feasible for biological control of some plant diseases and biosimulant agent for plant growth.
Silver chloride nanoparticles (AgCl-NPs) is a powerful antimicrobial agent. A possible source of ... more Silver chloride nanoparticles (AgCl-NPs) is a powerful antimicrobial agent. A possible source of biological material for the green biosynthesis of AgCl-NPs was represented by microalgae. In this study rapid biosynthesis of stable AgCl-NPs was achieved by using ethanol extract of cyanobacterium, Anabaena variabilis v. Kashiensis. The results were verified using UV-Vis spectroscopy, High Resolution Transmission Electron Microscopy (TEM) and X-ray diffraction (XRD). Bioreduction of Ag + ions showed a gradual change in the colour of the extract to brown. Peaks of UV-Vis spectra showed surface plasmon resonance (SPR) at (409 nm). TEM micrograph analyses confirmed formation of homogenous spherical AgCl-NPs, ranged in size from (12-20 nm). The crystalline nature of the synthesized AgCl-NPs was assigned by their remarkable peaks in the XRD patterns corresponding to (111, 200, 220, 311, 222, 400 and 420) planes. Fourier Transform Infrared Spectroscopy (FTIR) of purified nanoparticle fractions suggested that proteins were the main molecular entities involved in AgCl-NPs formation and stabilization. This study provides a new report for the cyanobacterial species, Anabaena variabilis that, could serve as good, cheap substrate for biogenic of homogenous spherical AgCl-NPs. [Seham M. Hamed, Manal M. Abdel-Alim, Neveen Abdel-Raouf, Ibraheem B.M. Ibraheem. Biosynthesis of silver chloride nanoparticles using the cyanobacterium Anabaena variabilis. Life Sci J 2017;14(6):25-30].
Beni-Suef University Journal of Basic and Applied Sciences, 2018
Marine macroalgae are plant-like organisms with simple internal structures that generally live in... more Marine macroalgae are plant-like organisms with simple internal structures that generally live in coastal areas. They mainly include different communities of red, brown and green macroalgae. Marine macroalgae commonly occupy intertidal and sublittoral-to-littoral zones on rocks and other hard substrata. They are considered to be an excellent natural biosource in different aspects of agricultural fields. They have great proficiency in improving soil physical and chemical properties. Marine macroalgae are also characterized by producing a large array of biologically active biocidal substances against plant-infecting pathogens. Unfortunately, most available literatures on marine macroalgae and their derivatives mainly focused on their pharmaceutical applications but their potential utilization in sustainable agriculture development is still often regarded as a secondary goal. However, a relatively considerable dataset on marine macroalgae showed that they could play a major role in plant protection and improvement. This review summarizes different aspects of potential macroalgal applications in agriculture. Commercial production and exploitation of specific compounds with interesting biotechnological importance from marine macroalgae including microbicides, nematicides, insecticides, biofertilizers, biostimulators and soil conditioners are highlighted and discussed in detail. Bioactive compounds like fatty acids (in particular polyunsaturated fatty acids (PUFAs), proteins (amino acids), bioflavonoids, sulfated polysaccharides, carotenoids, polyphenols and carbohydrates are considered to have bactericidal, antiviral and fungicidal effects against some plant-infecting pathogens. These biocontrol agents provide multiple benefits and act as useful pointers for improving cultivation practices in diverse habitats. Marine macroalgae can be generally considered as promising multifunctional bioinoculants and ecofriendly environmental tools in recent trends of organic farming.
The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Ana... more The dry biomass of four cyanobacterial microalgal strains Anabaena flos aquae, Anabanea laxa, Anabanea fertilissima and Nostoc muscorum was evaluated in invitro assay as a biopesticides against 2 nd and 4 th instars of Agrotis ipsilon. Larvae were fed on leaf discs painted with the algal solution for 24h. The 2 nd instar larvae were more susceptible than the 4 th ones to the four tested algal treatments. N. muscorum treatment was the most toxic one against the 2 nd and 4 th larval instars. Where, its LC 50 values were 45 and 150 mg/ml, respectively while, A. fertilissima was the least one, its LC 50 values were 250 and 660 mg/ ml, respectively. All the treated larvae were susceptible to four tested algal treatments and its resistance varied according to the larval instars and tested alga. Marked decrease in pupation for both 2 nd and /or 4 th instar by the four algal treatments, whereas, the 2 nd instar treated with N. muscorum alga exhibited the most suppressive decrease to 44%, as compared to control (97%). Significant reduction for pupal weight, where, 4 th instar treated with A. flos aquae alga recorded the highest pupal weight decrease to average 290mg, as compared to 484mg of control. Besides prolonging pupal duration where, treatment for both instar with A. flos aquae and A. laxa algae induced the longest period and increased the pupal malformation percent where, 4 th instar treated with N. muscorum and A. flos aquae algae induced noticeable percent reached to21.3 and20% and increased adult malformation to30 and20% respectively, as respect to control. However, the larval treatment of 2 nd instar with N. muscorum and A. fertilissima algae had the strongest effect in larval duration increase to average25 and 25.8day as compared to20.4day of control. In addition, the larval treatment of 4 th instar with the four algae decreased the adult fecundity and fertility. Moreover, N. muscorum and A. flos aquae algae inhibited the adult fecundity and eggs fertility to zero, as compared to505eggs/female of control. Marked declining of adult longevity with N. muscorum, A. flos aquae and A.laxa to average 7day, as compared to11day of control. Also, the treatment with the three algae disorder the sex ratio of males and females, as compared to that of control. While the larval treatment with A. fertilissima alga didn't affect the pupal malformation, eggs fertility, adult longevity and sex ratio.
Information available on the utilization of algae and cyanobacteria, with manifold potential appl... more Information available on the utilization of algae and cyanobacteria, with manifold potential applications in agriculture and biotechnology, for commercial biopesticide production is still scarce. We used the algal/cyanobacterial extract-larval contact method to assay in vitro against different developmental life cycle stages (the 2nd and 4th instars) of the cotton leafworm Spodoptera littoralis crude ethanolic extracts of five different algal and cyanobacterial species: Chara vulgaris (stonewort), Parachlorella kessleri, Ulva intestinalis, Cladophora glomerata (green algae), and the heterocytous cyanobacterium Nostoc carneum. All the algal and cyanobacterial treatments showed insecticidal activities against larvae of S. littoralis, with 2nd larval instars being more susceptible. In general, P. kessleri and N. carneum exhibited the highest insecticidal toxic effects while the stonewort C. vulgaris showed the lowest insecticidal activity. Effects of these algal and cyanobacterial treatments on larval duration, % pupal formation, pupal duration and weight, % moth emergence, adults’ fecundity and longevity, eggs’ hatching, sex ratios, and larval-pupal-moth malformations were discussed. Gas chromatography-mass spectrometry (GC-MS) analyses of the crude algal and cyanobacterial extracts revealed 29 compounds, mainly containing an array of saturated and unsaturated fatty acids, some essential oils, and terpene compounds like phytol. Insecticidal activities of the algal and cyanobacterial specimens can be attributed to the synergistic effects of the abovementioned phytochemical constituents, particularly fatty acids such as the polyunsaturated ω-6 linoleic, palmitic, oleic, myristic, α-linolenic, and 7, 10-hexadecadienoic acids. The coccoid green alga P. kessleri and the cyanobacterium N. carneum can thus be recommended as ecofriendly biopesticides for the integrated pest management of the cotton leafworm and other agricultural pests.
Crude extract of Anabaena flos aquae alga cyanobacterial strains was evaluated in laboratory as a... more Crude extract of Anabaena flos aquae alga cyanobacterial strains was evaluated in laboratory as a biocomponents against 2nd and 4th instars of the cotton leaf worm, Spodoptera littoralis (Boisd.). Larvae were treated with the algal extract via contact and feeding methods. Effect of the algal extract varied according to the larval instars and the method of application. Contact algal treatment was more effective than the feeding treatment. The 2nd larval instar was more susceptible than the 4th one. LC50 value for the 2nd larval instar of S. littoralis was 12.5 ppm compared with 25 ppm for the 4th instar. In case of feeding treatment, they were 50 and 100 ppm for the 2nd and 4th instars, respectively. LC50 value of the contact method induced highly significant increase of the larval and pupal durations, adults’ emergence decrease to 59.5%, compared with 99.7% for the untreated control. It induced the highest percentage of pupation (43%) and adults’ malformation reached 25%. Adults emerged from the treated 4th larval instar recorded high reduction in numbers of deposited egg (reached 28.3 eggs/ female) compared with (475 eggs/ female) for the control. Eggs fertility was decreased to 78.4% compared with 100% for the control. Highly significant reduction in the percentage of pupation was observed. Also, LC50 values obtained from the contact or feeding treatments on the 4th larval instar reduced the longevity of the resulted adults and percentage of the adults’ emergence. Disorder for the sex ratio was observed.
Variation in the traditional growth medium conditions to enhance the production of lipids, carboh... more Variation in the traditional growth medium conditions to enhance the production of lipids, carbohydrates, protein and the free amino acids content of three cyanobacterial species. Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.).
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Papers by Seham Moussa
species isolated from Egyptian paddy rice soil, having high 16S rRNA gene sequence
identity to Nostoc spongiaeforme, Parachlorella kessleri SAG 211-11 and Nostoc sp. PCC 7524)
under aerobic, anaerobic and 3% CO2-supplemented anaerobic condition. Significant
changes in photohydrogen production, morphology, chlorophyll a and protein content/
pattern were observed in all species, when grown in these different conditions. H2 production
was higher in anaerobic condition in all species with the highest H2 production
rate of 4 mmol H2 mg Chla1 h1 at 24 h in Synechocystis sp. In contrast, Chla content and
protein content decreased (%) in N. spongiaeforme, (29%, 58%), P. kessleri (47%, 7%) and Nostoc
sp. (59%, 65%).The anaerobic condition with 3% CO2 stimulated early production of H2 in all
species except Synechocystis sp. Our results compared all selected algal species under
different growth conditions for the screening of a superior H2-producing algal species that
can help to address engineering challenges in the field of large-scale H2 photoproduction by
microalgae.
areas. They mainly include different communities of red, brown and green macroalgae. Marine macroalgae
commonly occupy intertidal and sublittoral-to-littoral zones on rocks and other hard substrata. They
are considered to be an excellent natural biosource in different aspects of agricultural fields. They have
great proficiency in improving soil physical and chemical properties. Marine macroalgae are also characterized
by producing a large array of biologically active biocidal substances against plant-infecting pathogens.
Unfortunately, most available literatures on marine macroalgae and their derivatives mainly
focused on their pharmaceutical applications but their potential utilization in sustainable agriculture
development is still often regarded as a secondary goal. However, a relatively considerable dataset on
marine macroalgae showed that they could play a major role in plant protection and improvement.
This review summarizes different aspects of potential macroalgal applications in agriculture.
Commercial production and exploitation of specific compounds with interesting biotechnological importance
from marine macroalgae including microbicides, nematicides, insecticides, biofertilizers, biostimulators
and soil conditioners are highlighted and discussed in detail. Bioactive compounds like fatty acids
(in particular polyunsaturated fatty acids (PUFAs), proteins (amino acids), bioflavonoids, sulfated
polysaccharides, carotenoids, polyphenols and carbohydrates are considered to have bactericidal, antiviral
and fungicidal effects against some plant-infecting pathogens. These biocontrol agents provide multiple
benefits and act as useful pointers for improving cultivation practices in diverse habitats. Marine
macroalgae can be generally considered as promising multifunctional bioinoculants and ecofriendly environmental
tools in recent trends of organic farming.
and the free amino acids content of three cyanobacterial species.
Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc
muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture
Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using
BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium
with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a
concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid
content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose
at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g
fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested
cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g
fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high
significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation
period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited
high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.).
species isolated from Egyptian paddy rice soil, having high 16S rRNA gene sequence
identity to Nostoc spongiaeforme, Parachlorella kessleri SAG 211-11 and Nostoc sp. PCC 7524)
under aerobic, anaerobic and 3% CO2-supplemented anaerobic condition. Significant
changes in photohydrogen production, morphology, chlorophyll a and protein content/
pattern were observed in all species, when grown in these different conditions. H2 production
was higher in anaerobic condition in all species with the highest H2 production
rate of 4 mmol H2 mg Chla1 h1 at 24 h in Synechocystis sp. In contrast, Chla content and
protein content decreased (%) in N. spongiaeforme, (29%, 58%), P. kessleri (47%, 7%) and Nostoc
sp. (59%, 65%).The anaerobic condition with 3% CO2 stimulated early production of H2 in all
species except Synechocystis sp. Our results compared all selected algal species under
different growth conditions for the screening of a superior H2-producing algal species that
can help to address engineering challenges in the field of large-scale H2 photoproduction by
microalgae.
areas. They mainly include different communities of red, brown and green macroalgae. Marine macroalgae
commonly occupy intertidal and sublittoral-to-littoral zones on rocks and other hard substrata. They
are considered to be an excellent natural biosource in different aspects of agricultural fields. They have
great proficiency in improving soil physical and chemical properties. Marine macroalgae are also characterized
by producing a large array of biologically active biocidal substances against plant-infecting pathogens.
Unfortunately, most available literatures on marine macroalgae and their derivatives mainly
focused on their pharmaceutical applications but their potential utilization in sustainable agriculture
development is still often regarded as a secondary goal. However, a relatively considerable dataset on
marine macroalgae showed that they could play a major role in plant protection and improvement.
This review summarizes different aspects of potential macroalgal applications in agriculture.
Commercial production and exploitation of specific compounds with interesting biotechnological importance
from marine macroalgae including microbicides, nematicides, insecticides, biofertilizers, biostimulators
and soil conditioners are highlighted and discussed in detail. Bioactive compounds like fatty acids
(in particular polyunsaturated fatty acids (PUFAs), proteins (amino acids), bioflavonoids, sulfated
polysaccharides, carotenoids, polyphenols and carbohydrates are considered to have bactericidal, antiviral
and fungicidal effects against some plant-infecting pathogens. These biocontrol agents provide multiple
benefits and act as useful pointers for improving cultivation practices in diverse habitats. Marine
macroalgae can be generally considered as promising multifunctional bioinoculants and ecofriendly environmental
tools in recent trends of organic farming.
and the free amino acids content of three cyanobacterial species.
Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc
muscorum) were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture
Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using
BG110 (nitrogen free) as growth medium. These conditions were represented by control medium, static glucose medium
with (1%, w/v), aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a
concentration of 0.03%), molasses medium (0.7%, v/v) and aerated medium enriched with glucose (1%, w/v). Lipid
content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose
at 0.7% (w/v) was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g
fresh wt.). Increasing molasses concentration up to 0.7% (v/v) produced an increase in lipid contents of the tested
cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt.) and A. laxa (357.4 μg/g
fresh wt.) were recorded at molasses concentrations of 0.1 and 0.7% (v/v), respectively. A. laxa expressed high
significant values for both proteins (31.6 μg/mL) and free amino acids (40.5 mg/g dry wt.) after 6 days of incubation
period under aerated enriched glucose condition (1%, w/v). Also, at the same growth conditions, A. fertilissima exhibited
high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.).