The COVID-19 pandemic required higher education institutions to change the modality of face-to-fa... more The COVID-19 pandemic required higher education institutions to change the modality of face-to-face to online learning overnight. Adaptations were needed, particularly in industrial process training in Chemical Engineering and related careers. Students could not access companies and industries for internships or industrial visits, intended to allow undergraduate students to observe the process engineers’ work in professional spaces. This paper describes a pedagogical strategy to overcome this limitation. Here, we report an approach applied in an Industrial Processes course, with students from the 8th to 10th semesters and alumni, from the undergraduate Petrochemical Engineering program at Yachay Tech University (Ecuador). In this course, the students developed group projects involving an industrial process analysis focused on economic sectors of interest in the country. The projects also included a revision of official figures and statistics on production data, consumption, and pers...
Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and pro... more Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and properties of its fruit. In this study, hydrodistillation was used to isolate essential oil (EO) of fresh Annona cherimola leaves collected in Ecuadorian Sierra. The EO chemical composition was determined using a non-polar and a polar chromatographic column and enantiomeric distribution with an enantioselective column. The qualitative analysis was carried out by gas chromatography coupled to a mass spectrometer and quantitative analysis using gas chromatography equipped with a flame ionization detector. The antibacterial potency was assessed against seven Gram-negative bacteria and one Gram-positive bacterium. ABTS and DPPH assays were used to evaluate the radical scavenging properties of the EO. Spectrophotometric method was used to measure acetylcholinesterase inhibitory activity. GC-MS analysis allowed us to identify more than 99% of the EO chemical composition. Out of the fifty-three co...
Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine ... more Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the p...
Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for w... more Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11...
Neodymium is a key rare-earth element applied to modern devices. The purpose of this study is the... more Neodymium is a key rare-earth element applied to modern devices. The purpose of this study is the development of a hybrid biomaterial based on chitosan (CS) and manganese ferrite (MF) for the recovery of Nd(III) ions from the aqueous phase. The preparation of the beads was performed in two stages; first, MF particles were obtained by the assessment of three temperatures during the co-precipitation synthesis, and the best nano-MF crystallites were incorporated into CS to obtain the hybrid composite material (CS-MF). The materials were characterized by FTIR, XRD, magnetization measurements, and SEM-EDX. The adsorption experiments included pH study, equilibrium study, kinetics study, and sorption–desorption reusability tests. The results showed that for MF synthesis, 60 °C is an appropriate temperature to obtain MF crystals of ~30 nm with suitable magnetic properties. The final magnetic CS-MF beads perform maximum adsorption at pH 4 with a maximum adsorption capacity of 44.29 mg/g. Mor...
Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used t... more Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used to prepare the traditional beverage Guaviduca. Different health benefits are attributed to the guaviduca beverage, which is consumed as a traditional and folk medicine. In this study, fresh P. carpunya leaves were collected in the winter and summer and subjected to hydrodistillation for the extraction of the essential oil. The guaviduca beverage was prepared by infusion in water and the volatile compounds were isolated by liquid–liquid extraction. Chemical composition and enantioselective analyses were performed by gas chromatography. The antibacterial activity was assayed against Gram-positive and Gram-negative bacteria. The scavenging radical properties of the essential oil was evaluated by 2,2-diphenyl-1-picrylhydryl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The acetylcholinesterase inhibitory activity was measured using the spectrophotometric metho...
Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon r... more Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and...
Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine ... more Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the p...
Essential oils are highly demanded substances worldwide. They can be used without modification du... more Essential oils are highly demanded substances worldwide. They can be used without modification due to their different chemical and biological properties or as natural sources of chemical compounds. The limit in the use of these metabolites is their low yield. In the present investigation, the essential oil of fruits from Dacryodes peruviana collected in the Ecuadorian Amazon was extracted and studied. The essential oil was released from the plant matrix and isolated by hydrodistillation. The yields obtained were 4.8 ± 0.2% and 11.3 ± 0.2% for fresh and dried fruits, respectively, one of the highest yields on record to date. Twenty-five chemical compounds were identified by GC/MS and GC/FID techniques. The principal constituent was α-phellandrene, with 50.32 ± 3.32%. The antimicrobial activity of the oil was assayed against five Gram negative bacteria, two Gram positive bacteria and two fungi. The essential oil exerted a moderate activity against Staphylococcus aureus. The repellent ...
In this study the supercritical antisolventextraction process was used to fractionate and recover... more In this study the supercritical antisolventextraction process was used to fractionate and recovery polyphenolic compounds from mango by-products. The liquid extract was prepared by liquid-solid extraction in acetone and purification by adsorption/desorption in C18 column with ethanol. The Supercritical antisolvent extraction process parameters, pressure (8 – 15 MPa) and temperature (35 – 40ºC) were varied and their influence on the chemical composition and antioxidant power of the precipitated recovered was evaluated. The best conditions, 40ºC and 15 MPa, allow to obtain a precipitate as powder with a content of polyphenols of 911.94 mg gallic acid equivalent/g extract with an IC50 less than 0.05 mg/mL for antioxidant power, and increasing of concentration of polyphenolic compounds of 348.6 mg/kg mangiferin, 6.5 mg/kg isomangiferin, 5262.0 mg/kg quercetin 3-O glucoside, 750.2 mg/kg quercetin and 137.6 mg/kg kaempferol. The SAE preserves the polyphenolic compounds as confirmed by the...
ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compo... more ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compounds from mango by-products. The antioxidant extract was obtained by solid-liquid extraction using aqueous acetone (80% v/v) and subsequent adsorption/desorption in C18 cartridge. Recovery of antioxidants was performed by SAE using SC-CO2 as antisolvent. The temperature and pressure parameters were varied in the range 35-45°C and 8-15 MPa. The SAE process allowed the recovery of about 90% of the initial phenolic compounds, the best recovery was obtained at 40°C and 10 MPa and the main compounds were mangiferin, isomangiferin, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside, quercetin and kaempferol. The product obtained was a dry powder, spherical nanoparticles with a particle diameter of 143 ± 40 nm with an antioxidant activity of 851.9 μMol TE/g and a half inhibition concentration of DPPH radical of 90 μg/mL. The analyses performed indicated that SAE processing of natural extracts is effective for improving the activity of natural antioxidant compounds by producing nanoparticles.
ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compo... more ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compounds from mango by-products. The antioxidant extract was obtained by solid-liquid extraction using aqueous acetone (80% v/v) and subsequent adsorption/desorption in C18 cartridge. Recovery of antioxidants was performed by SAE using SC-CO2 as antisolvent. The temperature and pressure parameters were varied in the range 35-45°C and 8-15 MPa. The SAE process allowed the recovery of about 90% of the initial phenolic compounds, the best recovery was obtained at 40°C and 10 MPa and the main compounds were mangiferin, isomangiferin, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside, quercetin and kaempferol. The product obtained was a dry powder, spherical nanoparticles with a particle diameter of 143 ± 40 nm with an antioxidant activity of 851.9 μMol TE/g and a half inhibition concentration of DPPH radical of 90 μg/mL. The analyses performed indicated that SAE processing of natural extracts is effective for improving the activity of natural antioxidant compounds by producing nanoparticles.
ABSTRACT The essential oil of aerial parts of Baccharis latifolia (asteraceae) growing wild in Ec... more ABSTRACT The essential oil of aerial parts of Baccharis latifolia (asteraceae) growing wild in Ecuador was obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/flame ionization detector (GC/FID). Twenty-nine compounds, representing 90.91% of the oil, were identified. The major components were limonene (33.72%), -phellandrene (10.32%), sabinene (10.28%), β-pinene (6.99%) and α-pinene (5.44%). The antifungal and antibacterial activities were determined by the broth microdilution method. The essential oil from B. latifolia exhibited activity only against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185).
Amoxicillin represents the lead substance of the aminopenicillin group of beta-lactames, which is... more Amoxicillin represents the lead substance of the aminopenicillin group of beta-lactames, which is characterized by a broader antibacterial spectrum and acid-stability compared to penicillin G. In this book, the authors present current research in the study of the medical uses, mechanisms of action and potential adverse effects of amoxicillin. Topics discussed include microfibers of biodegradable polymers loaded with amoxicillin; the occurrence, fate and effects of amoxicillin in aquatic systems; accurate instrumental analytical methods for the quality control of amoxicillin in the pharmaceutical industry; and the pharmaceutical properties and clinical applications of amoxicillin. (Imprint: Nova Biomedical)
The aim of this work was to determine the chemical, technological and in vitro antioxidant proper... more The aim of this work was to determine the chemical, technological and in vitro antioxidant properties of co-products from the industrialisation of some tropical exotic fruits, such as mango, pineapple, guava and passion fruit, and to evaluate their potential use as dietary fibre sources for food enrichment. Proximate compositions were determined, as well as the total, insoluble and soluble fibre contents. The water holding, oil holding and swelling capacities were also determined. For the antioxidant activity, three different test systems were used (ABTS, DPPH and FRAP). The dietary fibre content of the co-products varied in a range between 69.1 and 81.5 g/100 g on a dry matter basis with a good balanced ratio between insoluble dietary fibre and soluble dietary fibre. Phenol recovery was dependent on the fruit type and the solvent system used. Methanol:acetone was a more efficient solvent for extracting phenols than ethanol. There was a good correlation between total phenol content and antioxidant capacity of the fruit extracts. All samples analysed had good antioxidant capacity. The results of this study indicate that exotic fruit fibres obtained as co-products in the process to obtain juice may be considered a good source of natural compounds with significant antioxidant activity.► Exotic fruits processing generated a great volume of co-products. ► Exotic fruits co-products are rich source of dietary fibre. ► They showed a high level of polyphenolic compounds. ► All samples analysed showed a good antioxidant capacity.
The COVID-19 pandemic required higher education institutions to change the modality of face-to-fa... more The COVID-19 pandemic required higher education institutions to change the modality of face-to-face to online learning overnight. Adaptations were needed, particularly in industrial process training in Chemical Engineering and related careers. Students could not access companies and industries for internships or industrial visits, intended to allow undergraduate students to observe the process engineers’ work in professional spaces. This paper describes a pedagogical strategy to overcome this limitation. Here, we report an approach applied in an Industrial Processes course, with students from the 8th to 10th semesters and alumni, from the undergraduate Petrochemical Engineering program at Yachay Tech University (Ecuador). In this course, the students developed group projects involving an industrial process analysis focused on economic sectors of interest in the country. The projects also included a revision of official figures and statistics on production data, consumption, and pers...
Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and pro... more Annona cherimola Mill. is a native species of Ecuador cultivated worldwide for the flavor and properties of its fruit. In this study, hydrodistillation was used to isolate essential oil (EO) of fresh Annona cherimola leaves collected in Ecuadorian Sierra. The EO chemical composition was determined using a non-polar and a polar chromatographic column and enantiomeric distribution with an enantioselective column. The qualitative analysis was carried out by gas chromatography coupled to a mass spectrometer and quantitative analysis using gas chromatography equipped with a flame ionization detector. The antibacterial potency was assessed against seven Gram-negative bacteria and one Gram-positive bacterium. ABTS and DPPH assays were used to evaluate the radical scavenging properties of the EO. Spectrophotometric method was used to measure acetylcholinesterase inhibitory activity. GC-MS analysis allowed us to identify more than 99% of the EO chemical composition. Out of the fifty-three co...
Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine ... more Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the p...
Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for w... more Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11...
Neodymium is a key rare-earth element applied to modern devices. The purpose of this study is the... more Neodymium is a key rare-earth element applied to modern devices. The purpose of this study is the development of a hybrid biomaterial based on chitosan (CS) and manganese ferrite (MF) for the recovery of Nd(III) ions from the aqueous phase. The preparation of the beads was performed in two stages; first, MF particles were obtained by the assessment of three temperatures during the co-precipitation synthesis, and the best nano-MF crystallites were incorporated into CS to obtain the hybrid composite material (CS-MF). The materials were characterized by FTIR, XRD, magnetization measurements, and SEM-EDX. The adsorption experiments included pH study, equilibrium study, kinetics study, and sorption–desorption reusability tests. The results showed that for MF synthesis, 60 °C is an appropriate temperature to obtain MF crystals of ~30 nm with suitable magnetic properties. The final magnetic CS-MF beads perform maximum adsorption at pH 4 with a maximum adsorption capacity of 44.29 mg/g. Mor...
Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used t... more Piper carpunya Ruiz & Pav. is an aromatic shrub native to Ecuador, the leaves of which are used to prepare the traditional beverage Guaviduca. Different health benefits are attributed to the guaviduca beverage, which is consumed as a traditional and folk medicine. In this study, fresh P. carpunya leaves were collected in the winter and summer and subjected to hydrodistillation for the extraction of the essential oil. The guaviduca beverage was prepared by infusion in water and the volatile compounds were isolated by liquid–liquid extraction. Chemical composition and enantioselective analyses were performed by gas chromatography. The antibacterial activity was assayed against Gram-positive and Gram-negative bacteria. The scavenging radical properties of the essential oil was evaluated by 2,2-diphenyl-1-picrylhydryl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. The acetylcholinesterase inhibitory activity was measured using the spectrophotometric metho...
Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon r... more Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and...
Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine ... more Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the p...
Essential oils are highly demanded substances worldwide. They can be used without modification du... more Essential oils are highly demanded substances worldwide. They can be used without modification due to their different chemical and biological properties or as natural sources of chemical compounds. The limit in the use of these metabolites is their low yield. In the present investigation, the essential oil of fruits from Dacryodes peruviana collected in the Ecuadorian Amazon was extracted and studied. The essential oil was released from the plant matrix and isolated by hydrodistillation. The yields obtained were 4.8 ± 0.2% and 11.3 ± 0.2% for fresh and dried fruits, respectively, one of the highest yields on record to date. Twenty-five chemical compounds were identified by GC/MS and GC/FID techniques. The principal constituent was α-phellandrene, with 50.32 ± 3.32%. The antimicrobial activity of the oil was assayed against five Gram negative bacteria, two Gram positive bacteria and two fungi. The essential oil exerted a moderate activity against Staphylococcus aureus. The repellent ...
In this study the supercritical antisolventextraction process was used to fractionate and recover... more In this study the supercritical antisolventextraction process was used to fractionate and recovery polyphenolic compounds from mango by-products. The liquid extract was prepared by liquid-solid extraction in acetone and purification by adsorption/desorption in C18 column with ethanol. The Supercritical antisolvent extraction process parameters, pressure (8 – 15 MPa) and temperature (35 – 40ºC) were varied and their influence on the chemical composition and antioxidant power of the precipitated recovered was evaluated. The best conditions, 40ºC and 15 MPa, allow to obtain a precipitate as powder with a content of polyphenols of 911.94 mg gallic acid equivalent/g extract with an IC50 less than 0.05 mg/mL for antioxidant power, and increasing of concentration of polyphenolic compounds of 348.6 mg/kg mangiferin, 6.5 mg/kg isomangiferin, 5262.0 mg/kg quercetin 3-O glucoside, 750.2 mg/kg quercetin and 137.6 mg/kg kaempferol. The SAE preserves the polyphenolic compounds as confirmed by the...
ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compo... more ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compounds from mango by-products. The antioxidant extract was obtained by solid-liquid extraction using aqueous acetone (80% v/v) and subsequent adsorption/desorption in C18 cartridge. Recovery of antioxidants was performed by SAE using SC-CO2 as antisolvent. The temperature and pressure parameters were varied in the range 35-45°C and 8-15 MPa. The SAE process allowed the recovery of about 90% of the initial phenolic compounds, the best recovery was obtained at 40°C and 10 MPa and the main compounds were mangiferin, isomangiferin, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside, quercetin and kaempferol. The product obtained was a dry powder, spherical nanoparticles with a particle diameter of 143 ± 40 nm with an antioxidant activity of 851.9 μMol TE/g and a half inhibition concentration of DPPH radical of 90 μg/mL. The analyses performed indicated that SAE processing of natural extracts is effective for improving the activity of natural antioxidant compounds by producing nanoparticles.
ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compo... more ABSTRACT Supercritical Antisolvent Extraction (SAE) was used in the recovery of antioxidant compounds from mango by-products. The antioxidant extract was obtained by solid-liquid extraction using aqueous acetone (80% v/v) and subsequent adsorption/desorption in C18 cartridge. Recovery of antioxidants was performed by SAE using SC-CO2 as antisolvent. The temperature and pressure parameters were varied in the range 35-45°C and 8-15 MPa. The SAE process allowed the recovery of about 90% of the initial phenolic compounds, the best recovery was obtained at 40°C and 10 MPa and the main compounds were mangiferin, isomangiferin, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin 3-O-xyloside, quercetin 3-O-arabinoside, quercetin and kaempferol. The product obtained was a dry powder, spherical nanoparticles with a particle diameter of 143 ± 40 nm with an antioxidant activity of 851.9 μMol TE/g and a half inhibition concentration of DPPH radical of 90 μg/mL. The analyses performed indicated that SAE processing of natural extracts is effective for improving the activity of natural antioxidant compounds by producing nanoparticles.
ABSTRACT The essential oil of aerial parts of Baccharis latifolia (asteraceae) growing wild in Ec... more ABSTRACT The essential oil of aerial parts of Baccharis latifolia (asteraceae) growing wild in Ecuador was obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and GC/flame ionization detector (GC/FID). Twenty-nine compounds, representing 90.91% of the oil, were identified. The major components were limonene (33.72%), -phellandrene (10.32%), sabinene (10.28%), β-pinene (6.99%) and α-pinene (5.44%). The antifungal and antibacterial activities were determined by the broth microdilution method. The essential oil from B. latifolia exhibited activity only against Trichophyton rubrum (ATCC 28188) and Trichophyton mentagrophytes (ATCC 28185).
Amoxicillin represents the lead substance of the aminopenicillin group of beta-lactames, which is... more Amoxicillin represents the lead substance of the aminopenicillin group of beta-lactames, which is characterized by a broader antibacterial spectrum and acid-stability compared to penicillin G. In this book, the authors present current research in the study of the medical uses, mechanisms of action and potential adverse effects of amoxicillin. Topics discussed include microfibers of biodegradable polymers loaded with amoxicillin; the occurrence, fate and effects of amoxicillin in aquatic systems; accurate instrumental analytical methods for the quality control of amoxicillin in the pharmaceutical industry; and the pharmaceutical properties and clinical applications of amoxicillin. (Imprint: Nova Biomedical)
The aim of this work was to determine the chemical, technological and in vitro antioxidant proper... more The aim of this work was to determine the chemical, technological and in vitro antioxidant properties of co-products from the industrialisation of some tropical exotic fruits, such as mango, pineapple, guava and passion fruit, and to evaluate their potential use as dietary fibre sources for food enrichment. Proximate compositions were determined, as well as the total, insoluble and soluble fibre contents. The water holding, oil holding and swelling capacities were also determined. For the antioxidant activity, three different test systems were used (ABTS, DPPH and FRAP). The dietary fibre content of the co-products varied in a range between 69.1 and 81.5 g/100 g on a dry matter basis with a good balanced ratio between insoluble dietary fibre and soluble dietary fibre. Phenol recovery was dependent on the fruit type and the solvent system used. Methanol:acetone was a more efficient solvent for extracting phenols than ethanol. There was a good correlation between total phenol content and antioxidant capacity of the fruit extracts. All samples analysed had good antioxidant capacity. The results of this study indicate that exotic fruit fibres obtained as co-products in the process to obtain juice may be considered a good source of natural compounds with significant antioxidant activity.► Exotic fruits processing generated a great volume of co-products. ► Exotic fruits co-products are rich source of dietary fibre. ► They showed a high level of polyphenolic compounds. ► All samples analysed showed a good antioxidant capacity.
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