Biochemical properties of red tilapia (Oreochromis niloticus) protein hydrolysates

The amino-acid composition, 2, 2-Diphenyl-1-picryhydrazyl (DPPH) radical-scavenging activity, and peptide patterns of tilapia protein hydrolysates produced by the enzymatic hydrolysis of Alcalase (AH), Flavourzyme (FH) and Protamex (PH) for 5h using pH-stat method were studied. The ratio of essential amino acids to non-essential amino acids increased after hydrolysis in all samples; however, no significant differences among them were observed. AH had a highest (P < 0.05) DPPH radical-scavenging activity, but no significant difference in the DPPH between FH and PH was observed. SDS-PAGE patterns for all the hydrolysates showed significant (P < 0.05) reduction in the number and the intensity of the bands with increasing time of hydrolysis. Flavourzyme showed the lowest rate of hydrolytic activity towards the tilapia mince

Effect of different drying treatments and solvent ratios on phytochemical constituents of Ipomoea aquatica and correlation with α-Glucosidase inhibitory activity

Ipomoea aquatica is an aquatic plant that is widely consumed in Southeast Asia as a vegetable. In this study, the influence of various ethanol ratios (0, 20, 50, 80, and 100%) as an extraction solvent and different drying methods including air drying, sun drying, and oven drying on phytochemical constituents of I. aquatica was investigated using a proton nuclear magnetic resonance-based metabolomics approach. The effect on α-glucosidase inhibitory activity and total phenolic content was also examined. Clear discrimination was observed between different ethanol ratios and different drying processes by principal component analysis. The highest α-glucosidase inhibitory activity was observed for absolute ethanol extract from the oven drying method with IC50 value of 204.0 ± 59.0 µg/mL and total phenolic content value of 22.0 ± 0.7 µg gallic acid equivalent/mg extract. Correlation between the α-glucosidase inhibitory activity and the metabolite were analyzed using a partial least square analysis. The metabolites that are responsible for the activity were quercetin derivatives, chlorogenic acid derivatives, sucrose, and fructose. This study highlights the basis for future investigations of I. aquatica as a source of food that has the potential for nutraceutical enhancement and as ingredient in medicinal preparation

Using a Near-Infrared Spectrometer to Estimate the Age of Anopheles Mosquitoes Exposed to Pyrethroids

We report on the accuracy of using near-infrared spectroscopy (NIRS) to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as <7 or ≥7 d old with an overall accuracy of 79%. The age categories of Anopheles mosquitoes that were not exposed to the insecticide papers were predicted with 78% accuracy whereas the age categories of resistant, susceptible and mosquitoes exposed to control papers were predicted with 82%, 78% and 79% accuracy, respectively. The ages of 85% of the wild-collected mixed-age Anopheles were predicted by NIRS as ≤8 d for both susceptible and resistant groups. The age structure of wild-collected mosquitoes was not significantly different for the pyrethroid-susceptible and pyrethroid-resistant mosquitoes (P = 0.210). Based on these findings, NIRS chronological age estimation technique for Anopheles mosquitoes may be independent of insecticide exposure and the environmental conditions to which the mosquitoes are exposed

Metabolomic analysis and biochemical changes in the urine and serum of streptozotocin-induced normal- and obese-diabetic rats

Diabetes mellitus (DM) is a chronic disease that can affect metabolism of glucose and other metabolites. In this study, the normal-and obese-diabetic rats were compared to understand the diabetes disorders of type 1 and 2 diabetes mellitus. This was done byevaluating their urine metabolites using proton nuclear magnetic resonance (1H NMR)-based metabolomics and comparing withcontrols at different time points, considering the induction periods of obesity and diabetes. The biochemical parameters of theserum were also investigated. The obese-diabetic model was developed by feeding the rats a high-fat diet and inducing diabeticconditions with a low dose of streptozotocin (STZ) (25 mg/kg bw). However, the normal rats were induced by a high dose of STZ(55 mg/kg bw). A partial least squares discriminant analysis (PLS-DA) model showed the biomarkers of both DM typescompared to control. The synthesis and degradation of ketone bodies, tricarboxylic (TCA) cycles, and amino acid pathwayswere the ones most involved in the variation with the highest impact. The diabetic groups also exhibited a noticeable increase inthe plasma glucose level and lipid profile disorders compared to the control. There was also an increase in the plasma cholesteroland low-density lipoprotein (LDL) levels and a decline in the high-density lipoprotein (HDL) of diabetic rats. The normal-diabetic rats exhibited the highest effect of all parameters compared to the obese-diabetic rats in the advancement of the DMperiod. This finding can build a platform to understand the metabolic and biochemical complications of both types of DM and cangenerate ideas for finding targeted drugs

Column efficiency of fluoride removal using Quaternized Palm Kernel Shell (QPKS)

In this research, the adsorption potential of quaternized palm kernel shell (QPKS) to remove F− from aqueous solution was investigated using fixed-bed adsorption column. Raw palm kernel shell waste was reacted with 3-chloro-2-hydroxypropyl trimethylammonium chloride (CHMAC) in order to modify the surface charge. The effects of inlet F− concentrations (2–12 mg/l) and QPKS bed height (2–10 cm) with optimum pH (pH = 3) on the breakthrough characteristics of the adsorption system were determined. In the fixed-bed column, breakthrough time increases with increasing bed height due to increasing amount of active site on adsorbents to adsorb the fluoride ion. Decreasing trend of breakthrough values was obtained with increasing initial fluoride concentration due to greater driving force for the transfer process to overcome the mass transfer resistance in the column. The adsorptions were fitted to three well-established fixed-bed adsorption models, namely, Thomas, Yoon–Nelson, and Adams–Bohart models. The results fitted well to the Thomas and Yoon–Nelson models with correlation coefficient, R2 ≥ 0.96

Effect of Different Drying Treatments and Solvent Ratios on Phytochemical Constituents of <i>Ipomoea aquatica</i> and Correlation with α-Glucosidase Inhibitory Activity

<p><i>Ipomoea aquatica</i> is an aquatic plant that is widely consumed in Southeast Asia as a vegetable. In this study, the influence of various ethanol ratios (0, 20, 50, 80, and 100%) as an extraction solvent and different drying methods including air drying, sun drying, and oven drying on phytochemical constituents of <i>I. aquatica</i> was investigated using a proton nuclear magnetic resonance-based metabolomics approach. The effect on α-glucosidase inhibitory activity and total phenolic content was also examined. Clear discrimination was observed between different ethanol ratios and different drying processes by principal component analysis. The highest α-glucosidase inhibitory activity was observed for absolute ethanol extract from the oven drying method with IC₅₀ value of 204.0 ± 59.0 µg/mL and total phenolic content value of 22.0 ± 0.7 µg gallic acid equivalent/mg extract. Correlation between the α-glucosidase inhibitory activity and the metabolite were analyzed using a partial least square analysis. The metabolites that are responsible for the activity were quercetin derivatives, chlorogenic acid derivatives, sucrose, and fructose. This study highlights the basis for future investigations of <i>I. aquatica</i> as a source of food that has the potential for nutraceutical enhancement and as ingredient in medicinal preparation.</p

Effect of Ipomoea aquatica ethanolic extract in streptozotocin (STZ) induced diabetic rats via 1H NMR-based metabolomics approach

Background: Ipomoea aquatica (locally known as “kangkung”) has previously been reported to have hypoglycemic activities on glucose level in diabetes patients. However, the effect of I. aquatica ethanolic extract on the metabolites in the body has remained unknown. Purpose: Our study provides new insights on the changes of endogenous metabolites causes by I. aquatica ethanolic extract and improves the understanding with regard of therapeutic efficacy and mechanism of I. aquatica ethanolic extract. Methods: By using a combination of 1H nuclear magnetic resonance (NMR) with multivariate analysis (MVDA), the changes of metabolites due to I. aquatica ethanolic extract administration in obese diabetic-induced Sprague Dawley rats (OB+STZ+IA) were identified. Results: The results suggested 19 potential biomarkers with variable importance projections (VIP) above 0.5, which include creatine/creatinine, glucose, creatinine, citrate, carnitine, 2- oxoglutarate, succinate, hippurate, leucine, 1-methylnicotinamice (MNA), taurine, 3- hydroxybutyrate (3-HB), tryptophan, lysine, trigonelline, allantoin, formate, acetoacetate (AcAc) and dimethylamine. From the changes in the metabolites, the affected pathways and aspects of metabolism were identified. Conclusion: I. aquatica ethanolic extract manages to increase metabolite levels such as creatinine/creatine, carnitine, MNA, trigonelline, leucine, lysine, 3-HB and decreases metabolite levels, including glucose and tricarboxylic acid (TCA) intermediates. This implies capabilities of I. aquatica ethanolic extract promoting glycolysis, gut microbiota and nicotinate/nicotinamide metabolism, improving the glomerular filtration rate (GFR) and reducing the β-oxidation rate. However, the administration of I. aquatica ethanolic extract has several drawbacks, such as unimproved changes in amino acid metabolism, especially in reducing branched chain amino acid (BCAA) synthesis pathways and lipid metabolis

Single linear-polarized and single circular-polarized slot antenna for WLAN application

This project proposed a single linear-polarized and a single circular-polarized patch antenna are design for WLAN applications at 2.4 GHz. This antenna is using FR-4 substrate with permittivity, ϵ r = 4.4 and the electrical conductivity tangent loss, tan Δ = 0.019. Three design antennas with same dimension size but with different feed line configuration had been consider as Design A, Design B and Design C. Design A and C have a better measured return loss of - 25.38 dB and - 24.384 dB, respectively. Beside that the Design B shows the performance of - 15.976 dB only

The effect of impregnation of activated carbon with SnCl2.2H2O on its porosity, surface composition and CO gas adsorption

Activated carbon was impregnated with different concentrations of SnCl .2H O. Unimpregnated and impregnated 2 2 activated carbons were analysed by means of physical adsorption and XPS and were tested for CO gas adsorption in a PSA system. The adsorption isotherms of N at 77 K were measured and showed a Type I isotherm indicating microporous 2 carbon for all the samples. The surface area, pore volume and pore size distribution were reduced with impregnation. XPS analysis showed an increase in the intensity of Sn3d peak with impregnation. The impregnated activated carbon showed a very good adsorption ability of CO gas compared to the unimpregnated sample. The adsorptive species responsible for CO gas adsorption was confirmed to be SnO instead of SnO due to the former’s comparative thermodynamic stability. 2 2002 Elsevier Science Ltd. All rights reserved