Jamil Harb
Birzeit University, Biology And Biochemistry, Faculty Member
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°C/min, 100 - 180 °C at 6 °C/min, 10 min at 180 °C. After recalculation of the results depending on the internal standard, r-factor were calculated for each aroma component and for each treatment as the value of peak area of that... more
°C/min, 100 - 180 °C at 6 °C/min, 10 min at 180 °C. After recalculation of the results depending on the internal standard, r-factor were calculated for each aroma component and for each treatment as the value of peak area of that component divided by the peak area value of the same ...
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Zusammenfassung Frisch geerntete Heidelbeeren (cv.'Bluecrop') wurden bei CA-Lagerbedingungen von 18% und 2% Sauerstoff (O 2) in Kombination mit steigenden Kohlendioxid (CO 2)-Konzentrationen von 6%, 12%, 18% und... more
Zusammenfassung Frisch geerntete Heidelbeeren (cv.'Bluecrop') wurden bei CA-Lagerbedingungen von 18% und 2% Sauerstoff (O 2) in Kombination mit steigenden Kohlendioxid (CO 2)-Konzentrationen von 6%, 12%, 18% und 24% CO 2 gelagert. ...
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To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE).... more
To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE). Metabolomic analyses of Chloroidium sp. UTEX 3007 indicated that the alga accumulates a broad range of carbon sources, including several desiccation tolerance-promoting sugars and unusually large stores of palmitate. Growth assays revealed capacities to grow in salinities from zero to 60 g/L and to grow heterotrophically on >40 distinct carbon sources. Assembly and annotation of genomic reads yielded a 52.5 Mbp genome with 8153 functionally annotated genes. Comparison with other sequenced green algae revealed unique protein families involved in osmotic stress tolerance and saccharide metabolism that support phenomic studies. Our results reveal the robust and flexible biology utilized by a green alga to successfully inhabit a desert coastline
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To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE).... more
To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE). Metabolomic analyses of Chloroidium sp. UTEX 3007 indicated that the alga accumulates a broad range of carbon sources, including several desiccation tolerance-promoting sugars and unusually large stores of palmitate. Growth assays revealed capacities to grow in salinities from zero to 60 g/L and to grow heterotrophically on >40 distinct carbon sources. Assembly and annotation of genomic reads yielded a 52.5 Mbp genome with 8153 functionally annotated genes. Comparison with other sequenced green algae revealed unique protein families involved in osmotic stress tolerance and saccharide metabolism that support phenomic studies. Our results reveal the robust and flexible biology utilized by a green alga to successfully inhabit a desert coastline.
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Interactive Venn diagram displaying shared and unique protein families (Pfams) among 6 different algae. File can be uploaded to interactivenn.net
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Green technology “phytoremediation” approach was applied in WadiA lsamin in Hebron-Palestine to evaluate the plant efficiency in remediation of soil that is polluted with chromium (Cr). An open field controlled experiment was conducted to... more
Green technology “phytoremediation” approach was applied in WadiA lsamin in Hebron-Palestine to evaluate the plant efficiency in remediation of soil that is polluted with chromium (Cr). An open field controlled experiment was conducted to assess the efficiency of two plant species, namely corn (Zea mays) and tobacco (Nicotiana tabacum), in remediating the Cr-polluted soil. The concentration of Cr metal was determined in all plant parts (root, stem, leaf and fruit) for both plants using ICP-AES. The accumulation of Cr was higher in leaves than in the other plant parts for both plants with order of leaf>stem>root>fruit for corn plant and leaf>stem>fruit>root for tobacco.
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Salt and cold are major abiotic stresses that have adverse effects on plant growth and development. To cope with these stresses and their detrimental effects plants have evolved several metabolic, biochemical and physiological processes... more
Salt and cold are major abiotic stresses that have adverse effects on plant growth and development. To cope with these stresses and their detrimental effects plants have evolved several metabolic, biochemical and physiological processes that are mainly triggered and mediated by the plant hormone abscisic acid (ABA). To elucidate the metabolic responses of the moss Physcomitrella patens, which serves as a model plant for abiotic stress adaptation, we performed GC-MS-based metabolic profiling of plants challenged for 5 and 28 h with either salt, cold or ABA. Our results indicate significant changes in the accumulation of several sugars including maltose, isomaltose and trehalose, amino acids including arginine, histidine, ornithine, tryptophan and tyrosine, and organic acids mainly citric acid and malonic acid. The metabolic responses provoked by ABA, cold and salt show considerable similarities. The accumulation of certain metabolites positively correlates with gene expression data w...
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Summary For two successive years gooseberries, ‘Achilles’ were stored at 1°C in regular air (control) and under six various CA conditions (%CO2+ %O2: 6+18; 12+18; 18+18; 12+2; 18+2 and 24+2). Results showed that air storage is not... more
Summary For two successive years gooseberries, ‘Achilles’ were stored at 1°C in regular air (control) and under six various CA conditions (%CO2+ %O2: 6+18; 12+18; 18+18; 12+2; 18+2 and 24+2). Results showed that air storage is not appropriate to handle gooseberries due to a drastic reduction in fruit firmness (25% lower than CA-treatments), darkening of fruit colour, mealy texture, and lower acidity level. Low oxygen storage in combination with high CO2 concentrations (18% or more) of gooseberries also gave bad results, mainly due to the development of off-flavours in fruits. However, results showed that increasing CO2-concentration up to 12% did not induce the development of off-flavour. It seems that the tolerance concentration for gooseberries in respect to CO2 lies between 12-15%, since fruits stored under 18% CO2 combined with 18% O2 were evaluated to be good fruits, although a slight off-flavour was noticed by panelists. Consequently, the storage of gooseberries ‘Achilles’ under 12-15% CO2 combined with 18% O2 for up to seven weeks can be recommended.
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Blueberries are highly perishable fruits, and consequently, storage under high CO2 and low O2 levels is recommended to preserve the highly appreciated polyphenols. However, high CO2 levels might be detrimental for certain cultivars. The... more
Blueberries are highly perishable fruits, and consequently, storage under high CO2 and low O2 levels is recommended to preserve the highly appreciated polyphenols. However, high CO2 levels might be detrimental for certain cultivars. The aim of this study was to investigate the impact of storage conditions on various quality parameters, including polyphenol composition in 'Duke' berries. Results show that storage under 18 kPa CO2, coupled with 3 kPa O2, resulted in accelerated softening of berries, which was accompanied by lower levels compared to other conditions of hexosides and arabinosides of malvidin, petunidin, cyanidine, and delphinidin. However, this storage condition had no negative impact on chlorogenic acid levels. Expression data of key polyphenol-biosynthesis genes showed higher expression levels of all investigated genes at harvest time compared to all storage conditions. Of particular importance is the expression level of chalcone synthase (VcCHS), which is sev...
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Research Interests: Food Science, Horticulture, Molecular Biology, Plant Biology, Biology, and 15 moreFood and Nutrition, Plant Molecular Biology, Plant Science, Gene expression, Horticultural Biotechnology, Polyphenols, Atmosphere, Color, Polyphenol in Foods, Gene, Gen, Burning, Controlled Atmosphere Storage, Polyphenol, and Horticultural production
Qalqilya is located at northern West Bank of Palest in . The city is surrounded with the Separation Wall built on their land by Isr ael. This colossal infrastructure prevents rainwater from flowing into flood plains a nd causes the city... more
Qalqilya is located at northern West Bank of Palest in . The city is surrounded with the Separation Wall built on their land by Isr ael. This colossal infrastructure prevents rainwater from flowing into flood plains a nd causes the city something it had never experienced before, floods. This thesis investigated environmental impacts of the Wall-induced floods of January 2013 on arable land facing the Separation Wall. Assessed parameters are soil bacte ria, h avy metal contents, soil structure, plant growth and socio-economic aspects. Higher microbial contamination was observed in flooded soils. There was no clear evidence of flood negative impacts on other parameters. However , the history of floods is short and continuous investigation will be needed t o further verify and understand environmental impacts of floods.
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Postharvest losses are expected in different stages: at harvest time, during storage, transport and marketing, or even after purchase by the consumer. Based on these facts, reducing postharvest food losses is a major agricultural goal in... more
Postharvest losses are expected in different stages: at harvest time, during storage, transport and marketing, or even after purchase by the consumer. Based on these facts, reducing postharvest food losses is a major agricultural goal in all countries. That is essential to feed the world''s expected 10 billion people within the next 40 to 50 years, and food production efficiency and distribution needs to be improved immensely. In this respect, postharvest losses are estimated to range from 10 to 30% per year despite the use of modern storage facilities and techniques. This book includes a study tested various environmental friendly techniques includes modified atmosphere packaging (MAP) using different types of plastic films, hot water dipping, and 1-methylcyclopropene (1-MCP) to maintain and preserve the quality of stored sweet bell peppers irrigated with saline water. In addition to that, it investigates the combination effect of the above treatments with different water s...
To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE).... more
To investigate the phenomic and genomic traits that allow green algae to survive in deserts, we characterized a ubiquitous species, Chloroidium sp. UTEX 3007, which we isolated from multiple locations in the United Arab Emirates (UAE). Metabolomic analyses of Chloroidium sp. UTEX 3007 indicated that the alga accumulates a broad range of carbon sources, including several desiccation tolerance-promoting sugars and unusually large stores of palmitate. Growth assays revealed capacities to grow in salinities from zero to 60 g/L and to grow heterotrophically on >40 distinct carbon sources. Assembly and annotation of genomic reads yielded a 52.5 Mbp genome with 8153 functionally annotated genes. Comparison with other sequenced green algae revealed unique protein families involved in osmotic stress tolerance and saccharide metabolism that support phenomic studies. Our results reveal the robust and flexible biology utilized by a green alga to successfully inhabit a desert coastline.
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The ‘Honeycrisp’ (HC) apple is new cultivar that has become very popular due to its flavor and unique texture characteristics. A distinct feature of the apple is that it maintains firmness over extended periods of time, including in air,... more
The ‘Honeycrisp’ (HC) apple is new cultivar that has become very popular due to its flavor and unique texture characteristics. A distinct feature of the apple is that it maintains firmness over extended periods of time, including in air, and thus differs from most cultivars. Our objective is to elucidate the biochemical changes and molecular mechanisms that are responsible for the slow softening of HC compared to a rapidly softening cultivar ‘McIntosh’ (MC). Fruits from both cultivars were picked during the normal harvest period and kept at 20 oC for two weeks. Internal ethylene concentrations (IECs) and flesh firmness of 5 fruit were measured every 3 d, and cortical tissue frozen in liquid nitrogen for further analysis. From these samples, the tissue of three fruit for each sampling date/cultivar was used for RNA extraction. Primers were designed for various ACC synthases (ACSs), ACC oxidases (ACOs), polygalacturonase (PGs), ethylene receptor (ETRs and ERSs), xyloglucan endotransgl...
Cultivation of grapes in West Bank - Palestine is very old and a large number of grape varieties exist as a result of continuous domestication over thousands of years. This rich biodiversity has highly influenced the consumer behavior of... more
Cultivation of grapes in West Bank - Palestine is very old and a large number of grape varieties exist as a result of continuous domestication over thousands of years. This rich biodiversity has highly influenced the consumer behavior of local people, who consume both grape berries and leaves. However, studies that address the contents of health-promoting metabolites in leaves are scarce. Accordingly the aim of this study is to assess metabolite levels in leaves of two grape varieties that were collected from semiarid and temperate regions. Metabolic profiling was conducted using GC-MS and LC-MS. The obtained results show that abiotic stresses in the semiarid region led to clear changes in primary metabolites, in particular in amino acids, which exist at very high levels. By contrast, qualitative and genotype-dependent differences in secondary metabolites were observed, whereas abiotic stresses appear to have negligible effect on the content of these metabolites. The qualitative dif...
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Grape leaves (Vitis vinifera L.) are widely consumed in Palestine, and other Mediterranean countries. Positive health effects of grape products are reported by various studies and pharmaceutical preparations from grape leaves are patented... more
Grape leaves (Vitis vinifera L.) are widely consumed in Palestine, and other Mediterranean countries. Positive health effects of grape products are reported by various studies and pharmaceutical preparations from grape leaves are patented and commercialized as drugs. The aim of this in vitro study is to assess the therapeutic potential of leaf extracts; their cytotoxicity against lung cancerous cells, their antioxidant and antimicrobial activity against several human pathogenic bacterial strains, and according to geographical location, to examine the overall effect of annual rainfall on the aforementioned activities. Leaves from Shami and Baituni grapes, collected from Dahria (an arid region) and Beit Omar (a temperate region) in Palestine were ground to powder using liquid nitrogen and a pestle and mortar. Cytotoxicity was measured against lung cancer cells and muscle cells. Antioxidants potential of leaf extracts and antimicrobial activity against five human pathogenic bacterial strains were assessed. R...
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Grape leaves are widely consumed in Palestine, and many Mediterranean countries. This food item is considered as a delicacy in many cultures, and most consumers consider it as also a healthy food. Accordingly, we started two years ago a... more
Grape leaves are widely consumed in Palestine, and many Mediterranean countries. This food item is considered as a delicacy in many cultures, and most consumers consider it as also a healthy food. Accordingly, we started two years ago a study to assess the nutritional quality of leaves collected from two grape varieties, namely Shami and Baituni, which were collected from two regions, namely Dahria (considered as an arid region) and Beit Umar (considered as temperate region). Leaves were collected during spring time in three replicates and directly grinded to powder in liquid nitrogen. To assess the nutritional quality, leaf extract were tested as anticancer agent, and tested further for the total antioxidants potential. Moreover, leaf extracts were subjected to detailed analysis for active compounds using GC-MS and LC-MS. Results show that leaves from Shami grapes clearly inhibited the proliferation of lung cancer cells. Concerning the influence of cultivation area, Shami leaves from the temperate region (Beit Umar) proved to be more effective that those collected from Dahria (the arid region). In addition, leaves from Baituni grapes proved to be ineffective against lung cancer. In contrast, the GC-MS analyses of primary metabolites show that leaves of both grape varieties, which were collected from the arid region, contain higher levels of a large set of compounds including alanine, valine, isoleucine, proline, serine, threonine, uracil, sorbose, malitol, quercetin, and maltotriose. This dramatic increase in these compounds may be attributed to osmotic adjustment of plants to cope with drought stress prevailed in that region compared to the temperate region. The analyses for secondary metabolites and total antioxidants potential are closed and will be represented, in connection with changes in primary metabolites and anticancer activity of grape leave extracts. In conclusion, results clearly show that consumption of grape leaves is very healthy, and its consumption may contribute to Mediterranean diet by preventing the occurrence of severe diseases. Moreover, detailed analyses using GC-MS, and LC-MS may reveal the active compounds behind the health-promoting impact of grape leaves. Further purification of these compounds may allow for future usage of leaf extract of Shami grapes as natural pharmaceuticals.
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ABSTRACT
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ABSTRACT The ‘Honeycrisp’ (HC) apple is new cultivar that has become very popular due to its flavor and unique texture characteristics. A distinct feature of the apple is that it maintains firmness over extended periods of time, including... more
ABSTRACT The ‘Honeycrisp’ (HC) apple is new cultivar that has become very popular due to its flavor and unique texture characteristics. A distinct feature of the apple is that it maintains firmness over extended periods of time, including in air, and thus differs from most cultivars. Our objective is to elucidate the biochemical changes and molecular mechanisms that are responsible for the slow softening of HC compared to a rapidly softening cultivar ‘McIntosh’ (MC). Fruits from both cultivars were picked during the normal harvest period and kept at 20 oC for two weeks. Internal ethylene concentrations (IECs) and flesh firmness of 5 fruit were measured every 3 d, and cortical tissue frozen in liquid nitrogen for further analysis. From these samples, the tissue of three fruit for each sampling date/cultivar was used for RNA extraction. Primers were designed for various ACC synthases (ACSs), ACC oxidases (ACOs), polygalacturonase (PGs), ethylene receptor (ETRs and ERSs), xyloglucan endotransglucosylase (XTHs), expansions (EXPs), β-galactosidase (β-Gal), and arabinofuranosidase (AFase) genes, and used for quantitative real time RT-PCR (qPCR) analyses. The results show that HC fruit kept at 20oC had lower IECs, both at harvest and storage, than MC fruit. Also, while MC fruit lost more than 33% of their initial firmness values, HC fruit remain almost as firm as at harvest. The qPCR results revealed that the expression of ACO1, ACO2, ACS1, ACS3, ERS1, ETR1, ETR12, ERF1, ERF2, and β-Gal genes by HC fruit were either higher than or equivalent in all dates to the expression level by MC fruits. It was evident that the expression of ACO and ACS genes in the earlier dates was much higher than MC fruits. However, the expression of AFase, PG, and EXP3 genes was significantly higher, at most dates, with MC fruit.
ABSTRACT The genetic diversity of 13 local Palestinian fig genotypes was investigated using RAPD markers. Among the 30 tested primers, 28 revealed various banding patterns and 2 generated no polymorphic bands. In addition, 13 primers... more
ABSTRACT The genetic diversity of 13 local Palestinian fig genotypes was investigated using RAPD markers. Among the 30 tested primers, 28 revealed various banding patterns and 2 generated no polymorphic bands. In addition, 13 primers (46.4%) produced good amplification products with high intensity and pattern stability. A total of 94 DNA fragments (loci), separated by electrophoresis on agarose gel were detected, ranging in size from 190 to 1300 bp. Of these fragments, 72 (76.6%) were polymorphic and 22 (23.4%) were monomorphic. A minimum of three and a maximum of eight DNA fragments were obtained using (OPH-02 and OPT-10) as well as (OPA-13, OPA-18 and OPY-07) primers respectively. The maximum percentage of polymorphic markers was 100.0 (Z-5, Z-12, and OPT-10) and the minimum was 60.0 (OPH-02). Primers OPY-07 and OPA-13 revealed high collective resolving power (Rp) values with 4.640 and 4.760 respectively and therefore, they were the most useful RAPD primers to assess the genetic diversity in the Palestinian figs. Genetic distance matrix showed an average distance range from 0.186 to 0.559 with a mean of 0.373. Thus, the cultivars tested in this study were characterized by large divergence at the DNA level. To our knowledge, this is the first report using RAPD marker to assess genetic diversity of Palestinian figs.
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ABSTRACT The postharvest quality of Jew’s mallow was tested using two types of plastic liners and two temperatures, 4ºC and 10ºC. The plastic liners were normally sealed low density polyethylene and modified atmosphere package. Six... more
ABSTRACT The postharvest quality of Jew’s mallow was tested using two types of plastic liners and two temperatures, 4ºC and 10ºC. The plastic liners were normally sealed low density polyethylene and modified atmosphere package. Six quality parameters (weight loss, chlorophyll content, decay level, dryness level, yellowing level and chilling injury) were studied. It was found that Jew’s mallow leaves had a longer shelf life at 4ºC than at 10ºC. Modified atmosphere package liner showed a good result with respect to decay level. The shelf life was two weeks.
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Zusammenfassung Frisch geerntete Heidelbeeren (cv.'Bluecrop') wurden bei CA-Lagerbedingungen von 18% und 2% Sauerstoff (O 2) in Kombination mit steigenden Kohlendioxid (CO 2)-Konzentrationen von 6%, 12%, 18% und 24% CO 2... more
Zusammenfassung Frisch geerntete Heidelbeeren (cv.'Bluecrop') wurden bei CA-Lagerbedingungen von 18% und 2% Sauerstoff (O 2) in Kombination mit steigenden Kohlendioxid (CO 2)-Konzentrationen von 6%, 12%, 18% und 24% CO 2 gelagert. ...
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°C/min, 100 - 180 °C at 6 °C/min, 10 min at 180 °C. After recalculation of the results depending on the internal standard, r-factor were calculated for each aroma component and for each treatment as the value of peak area of that... more
°C/min, 100 - 180 °C at 6 °C/min, 10 min at 180 °C. After recalculation of the results depending on the internal standard, r-factor were calculated for each aroma component and for each treatment as the value of peak area of that component divided by the peak area value of the same ...
