The chemical composition of Pellonula leonensis fish oils from the Congo River (at Boko city) was carried out. The fatty acids were determined by gas chromatography. The Sn-2 position of fatty acids on glycerol was ca...The chemical composition of Pellonula leonensis fish oils from the Congo River (at Boko city) was carried out. The fatty acids were determined by gas chromatography. The Sn-2 position of fatty acids on glycerol was carried out by the ISO 6800 standard. The separation of the compounds (as free fatty acids, monoglycerides, diglycerides, triglycerides, sterols and methyl esters, etc.) was carried out by HPLC using gel permeation with refractometric detection. The phospholipid composition was by HPLC with an evaporative light scattering detector. We obtained oil contents of 32.10 (±0.46)%. The major fatty acids were Palmitic acid (27.41%) and oleic acid (24.23%). The SFA were of 44.50%. The MUFA represent 32.54% and PUFA 22.60%. Regarding the Sn-2 position on glycerol, 48.0% were by SFA and 51.3% were by unsaturated fatty acids. Among them 34.2% of fatty acids were 17.5% oleic acid molecules, 3.3% DHA molecules and 2.1% EPA molecules. Free fatty acids have contents of more than 62%, Diglycerides 16.63% and triglycerides 20.46%. Seven different phospholipids were identified, namely: Phosphatidylglycerol (PG), Phosphatidylethanolamine (PE), Phosphatidylinositol (PI), Phosphatidylcholine (PC), Sphingomyelin (SM), Lyso Phosphatitdylcholine (LPC) and Lyso Phosphatidylethanolamine (LPE). According to the high levels in position 2 of the glycerol of palmitic acid, the consumption of Pellonula leonensis fish could be moderate.展开更多
Citrus family especially Grapefruit,has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties.The juice and essential oil ext...Citrus family especially Grapefruit,has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties.The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties.The total soluble solids(TSS),titratable acidity(TA) and pH of juice samples extracted from various grapefruit varieties differed significantly.The refractive index,specific gravity and optical rotation values for the oil varied from 1.473 to 1.396,0.863 to 0.847 and +93 to +86,respectively.The percent 2,2-diphenyl-1-picrylhydrazyl radical activity(% DPPH activity) and ferric reducing antioxidant power(FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79,2.91 to 1.44 mmol g^–1 and 84.87 to 74.73,7.76 to 5.73 mmol g^-1,respectively.There were significant differences in physicochemical,antioxidant properties and volatile profiles of extracted juice and oil.The oil exhibited higher DPPH and FRAP values than the juice.Among different components identified which accounted for over 99% of the volatile fraction,limonene,myrcene,and benzopyran were major components in all oil samples.展开更多
Assessing the impact of climate change(CC)on agricultural production systems is mainly done using crop models associated with climate model outputs.This review is one of the few,with the main objective of providing a ...Assessing the impact of climate change(CC)on agricultural production systems is mainly done using crop models associated with climate model outputs.This review is one of the few,with the main objective of providing a recent compendium of CC impact studies on irrigation needs and rice yields for a better understanding and use of climate and crop models.We discuss the strengths and weaknesses of climate impact studies on agricultural production systems,with a particular focus on uncertainty and sensitivity analyses of crop models.Although the new generation global climate models(GCMs)are more robust than previous ones,there is still a need to consider the effect of climate uncertainty on estimates when using them.Current GCMs cannot directly simulate the agro-climatic variables of interest for future irrigation assessment,hence the use of intelligent climate tools.Therefore,sensitivity and uncertainty analyses must be applied to crop models,especially for their calibration under different conditions.The impacts of CC on irrigation needs and rice yields vary across regions,seasons,varieties and crop models.Finally,integrated assessments,the use of remote sensing data,climate smart tools,CO_(2)enrichment experiments,consideration of changing crop management practices and multi-scale crop modeling,seem to be the approaches to be pursued for future climate impact assessments for agricultural systems。展开更多
Nano-encapsulation is a platform which offers a promising application for control release and the delivery of drugs in pharmaceuticals and antioxidant/ antimicrobial in food systems. Poly (lactic-co-glycolide acid) (P...Nano-encapsulation is a platform which offers a promising application for control release and the delivery of drugs in pharmaceuticals and antioxidant/ antimicrobial in food systems. Poly (lactic-co-glycolide acid) (PLGA) is a biodegradable and biocompatible co-polymer of lactic acid and glycolic acid which is used for synthesizing food based polymeric nanoparticles (NP). The aim of this study was to evaluate the morphological and physicochemical properties and the controlled release of bioactive components derived from Aloe vera gel loaded PLGA NP. The results shows the mean hydrodynamic diameter of the unloaded NP is 103 nm which is significantly (p < 0.01) smaller than the loaded freeze dried powered gel (FDG) (147 nm) and liquid gel (LG) (221 nm) and the particle size distribution given by the Poly-dispersity Index were 0.2, 0.2 and 0.3, respectively. The zeta potential for unloaded, FDG and LG NP were ±60, ±28 and ±22 mV, respectively, hence were electrokinetically stable NP. No significant (p > 0.05) inhibition of the antioxidant potential was observed with loaded NP. The entrapment efficiency for the FDG synthesized was 87%, and the burst effect was observed after 4 h as a result of the encapsulation effect. The release kinetics of bioactive is govern by the combination of mass diffusion and capillary action.展开更多
Biosynthesis of silver nanoparticles (AgNP) using biomolecular extracts of plant origin is of interest to many researchers because of their potential to produced stable product. It is hypothesized that laser ablation ...Biosynthesis of silver nanoparticles (AgNP) using biomolecular extracts of plant origin is of interest to many researchers because of their potential to produced stable product. It is hypothesized that laser ablation of the AgNP in solution will enhance the biomolecules such as aliphatic amines, alkenes (=C-H), alkanes (C-H), alcohol (O-H) and unsaturatedesters (C-O) in the Nano emulsion. Hence, the objective of this study was to evaluate the effect of laser oblation on the physicochemical properties and stability of AgNP reduced with Aloe vera (Aloe barbadensis ). Experiments were conducted with the pre-made AgNP were subjected to the three laser oblation treatments: 1) Control no laser treatment of AgNP, 2) Laser ablation treatment for 5 minutes and 3) Laser ablation treatment for 10 minutes. The results of the analysis show that laser oblation treatment has significant effect (p < 0.01) on the concentration of AgNP. The intensity of the absorption peak significantly (p < 0.01) increases with laser exposure time. While 214 ppm was observed with no laser treatment, 224 and 229 ppm increase of concentration was observed when laser treated for 5 and 10 min. The rates of reaction of restructuring the particles sizes were 0.384, 0.408 and 0.4288 min-1 at different laser exposure treatments times 0, 5 and 10 min, respectively. The FTIR results show significant (p < 0.05) increase in biomolecules concentration of aliphatic amines, alkenes (=C-H), alkanes (C-H), alcohol (O-H) and unsaturatedesters (C-O).展开更多
文摘The chemical composition of Pellonula leonensis fish oils from the Congo River (at Boko city) was carried out. The fatty acids were determined by gas chromatography. The Sn-2 position of fatty acids on glycerol was carried out by the ISO 6800 standard. The separation of the compounds (as free fatty acids, monoglycerides, diglycerides, triglycerides, sterols and methyl esters, etc.) was carried out by HPLC using gel permeation with refractometric detection. The phospholipid composition was by HPLC with an evaporative light scattering detector. We obtained oil contents of 32.10 (±0.46)%. The major fatty acids were Palmitic acid (27.41%) and oleic acid (24.23%). The SFA were of 44.50%. The MUFA represent 32.54% and PUFA 22.60%. Regarding the Sn-2 position on glycerol, 48.0% were by SFA and 51.3% were by unsaturated fatty acids. Among them 34.2% of fatty acids were 17.5% oleic acid molecules, 3.3% DHA molecules and 2.1% EPA molecules. Free fatty acids have contents of more than 62%, Diglycerides 16.63% and triglycerides 20.46%. Seven different phospholipids were identified, namely: Phosphatidylglycerol (PG), Phosphatidylethanolamine (PE), Phosphatidylinositol (PI), Phosphatidylcholine (PC), Sphingomyelin (SM), Lyso Phosphatitdylcholine (LPC) and Lyso Phosphatidylethanolamine (LPE). According to the high levels in position 2 of the glycerol of palmitic acid, the consumption of Pellonula leonensis fish could be moderate.
基金support in the form of INSPIRE(Innovation in Science Pursuit for Inspired Research)Fellowship(IF140221)during his PhD program
文摘Citrus family especially Grapefruit,has attained considerable attention due to the presence of a number of essential components that have cardiovascular and anti-hypertensive properties.The juice and essential oil extracted from eight recently released grapefruit cultivars were used to study physicochemical and antioxidant properties.The total soluble solids(TSS),titratable acidity(TA) and pH of juice samples extracted from various grapefruit varieties differed significantly.The refractive index,specific gravity and optical rotation values for the oil varied from 1.473 to 1.396,0.863 to 0.847 and +93 to +86,respectively.The percent 2,2-diphenyl-1-picrylhydrazyl radical activity(% DPPH activity) and ferric reducing antioxidant power(FRAP) values for grapefruit juice and peel oil varied from 24.06 to 18.79,2.91 to 1.44 mmol g^–1 and 84.87 to 74.73,7.76 to 5.73 mmol g^-1,respectively.There were significant differences in physicochemical,antioxidant properties and volatile profiles of extracted juice and oil.The oil exhibited higher DPPH and FRAP values than the juice.Among different components identified which accounted for over 99% of the volatile fraction,limonene,myrcene,and benzopyran were major components in all oil samples.
基金financially supported by the Strategic Support Program for Scientific Research (PASRES), C?te d’Ivoire, Project N202, 2nd session 2018
文摘Assessing the impact of climate change(CC)on agricultural production systems is mainly done using crop models associated with climate model outputs.This review is one of the few,with the main objective of providing a recent compendium of CC impact studies on irrigation needs and rice yields for a better understanding and use of climate and crop models.We discuss the strengths and weaknesses of climate impact studies on agricultural production systems,with a particular focus on uncertainty and sensitivity analyses of crop models.Although the new generation global climate models(GCMs)are more robust than previous ones,there is still a need to consider the effect of climate uncertainty on estimates when using them.Current GCMs cannot directly simulate the agro-climatic variables of interest for future irrigation assessment,hence the use of intelligent climate tools.Therefore,sensitivity and uncertainty analyses must be applied to crop models,especially for their calibration under different conditions.The impacts of CC on irrigation needs and rice yields vary across regions,seasons,varieties and crop models.Finally,integrated assessments,the use of remote sensing data,climate smart tools,CO_(2)enrichment experiments,consideration of changing crop management practices and multi-scale crop modeling,seem to be the approaches to be pursued for future climate impact assessments for agricultural systems。
文摘Nano-encapsulation is a platform which offers a promising application for control release and the delivery of drugs in pharmaceuticals and antioxidant/ antimicrobial in food systems. Poly (lactic-co-glycolide acid) (PLGA) is a biodegradable and biocompatible co-polymer of lactic acid and glycolic acid which is used for synthesizing food based polymeric nanoparticles (NP). The aim of this study was to evaluate the morphological and physicochemical properties and the controlled release of bioactive components derived from Aloe vera gel loaded PLGA NP. The results shows the mean hydrodynamic diameter of the unloaded NP is 103 nm which is significantly (p < 0.01) smaller than the loaded freeze dried powered gel (FDG) (147 nm) and liquid gel (LG) (221 nm) and the particle size distribution given by the Poly-dispersity Index were 0.2, 0.2 and 0.3, respectively. The zeta potential for unloaded, FDG and LG NP were ±60, ±28 and ±22 mV, respectively, hence were electrokinetically stable NP. No significant (p > 0.05) inhibition of the antioxidant potential was observed with loaded NP. The entrapment efficiency for the FDG synthesized was 87%, and the burst effect was observed after 4 h as a result of the encapsulation effect. The release kinetics of bioactive is govern by the combination of mass diffusion and capillary action.
文摘Biosynthesis of silver nanoparticles (AgNP) using biomolecular extracts of plant origin is of interest to many researchers because of their potential to produced stable product. It is hypothesized that laser ablation of the AgNP in solution will enhance the biomolecules such as aliphatic amines, alkenes (=C-H), alkanes (C-H), alcohol (O-H) and unsaturatedesters (C-O) in the Nano emulsion. Hence, the objective of this study was to evaluate the effect of laser oblation on the physicochemical properties and stability of AgNP reduced with Aloe vera (Aloe barbadensis ). Experiments were conducted with the pre-made AgNP were subjected to the three laser oblation treatments: 1) Control no laser treatment of AgNP, 2) Laser ablation treatment for 5 minutes and 3) Laser ablation treatment for 10 minutes. The results of the analysis show that laser oblation treatment has significant effect (p < 0.01) on the concentration of AgNP. The intensity of the absorption peak significantly (p < 0.01) increases with laser exposure time. While 214 ppm was observed with no laser treatment, 224 and 229 ppm increase of concentration was observed when laser treated for 5 and 10 min. The rates of reaction of restructuring the particles sizes were 0.384, 0.408 and 0.4288 min-1 at different laser exposure treatments times 0, 5 and 10 min, respectively. The FTIR results show significant (p < 0.05) increase in biomolecules concentration of aliphatic amines, alkenes (=C-H), alkanes (C-H), alcohol (O-H) and unsaturatedesters (C-O).
