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关键词： Citrullus   Lanatus   Colocynthis   Fatty acids   Antioxidant   Clastogenic  

摘要： Citrullus colocynthis (C. colocynthis) seed is a common and expensive cuisine in West African diet unlike the seeds from Citrullus lanatus (C. lanatus) that are agro waste. The oils from these seeds were comparatively profiled using their physicochemical properties, fatty acids and phenolic contents, in-vitro antioxidant capacity (DPPH, TEAC, FRAP, ORAC), inhibitions of lipid peroxidation and tyrosinase. Toxicities of the oils in mice were also assessed using plasma AST, ALT, cholesterol, HDL-C, liver, heart and kidney (GSH, GPx and SOD) and clastogenic effects in mouse bone marrow. Citrullus lanatus oil contains higher peroxides, saponification, saturated fatty acids and stearic acid (6-fold) levels, with a lower acid value when compared to C. colocynthis. Strong antioxidant capacity, inhibition of lipid peroxidation and tyrosinase by C. lanatus oil extract is proposed to be related to the presence of catechins that are absent in C. colocynthis. The in-vivo study indicated that C. lanatus induced significant increase in ALT while a significant increase of AST was observed in the C. colocynthis treated group. Citrullus lanatus induced a significantly (p<0.05) higher heart GPx activity when compared with C. colocynthis and the control groups. Both oils did not affect SOD activity and showed no clastogenic effect in mouse bone marrow (p>0.05). This work reports for the first time the presence of stearic acid and catechin in C. lanatus oil which is important for its compelling in vitro activity. High doses of both oils could evidently induce toxicological indices in mice. (C) 2021 SAAB. Published by Elsevier B.V. All rights reserved.

关键词： endosperm type   nitrogen fertilization   rice flour   starch structure  

摘要： Background and objectives This study was conducted to determine the effect of nitrogen fertilization level during cultivation on physicochemical properties of two floury rice varieties (Shingil and Garumi 2) with different endosperm types under dry-milling process. Findings In both varieties, the protein content was increased in proportion to the level of nitrogen fertilization, while the amylose content exhibited a slight decrease in the highest nitrogen fertilization level. Damaged starch and digestible starch fractions were decreased with increasing nitrogen fertilization for both varieties, maybe due to the reduction in total starch relative to the protein content. Nevertheless, the level of damaged starch increased in Shingil under the highest nitrogen fertilization of 270 kg/ha, suggesting that nitrogen fertilization level can affect the physicochemical characteristics of starch particles during dry milling. The proportion of short amylopectin chains (DP6-12) decreased with increasing nitrogen fertilization. The difference was more prominent in Shingil than the other variety Garumi 2, indicating that Shingil could experience a greater increase in hardening and a faster retrogradation by increased nitrogen fertilization level than Garumi 2. Conclusions Nitrogen fertilization levels during rice growth affected the starch and protein contents in the endosperm, the chain length of amylopectin, which should, in turn, contribute to the processing properties of floury rice varieties. Significance and novelty This study will help develop fertilization strategies for the novel floury rice varieties and consequently provide helpful information to the rice-processing food industry.

关键词： Carotenoids   Chlamydomonas reinhardtii   Ethyl lauroyl alginate (LAE)   Polysorbate 80 (Tween 80)   Sodium dodecyl sulfate (SDS)  

摘要： Lutein (L) and zeaxanthin (Z), as macular pigments, are water-insoluble, chemically unstable, and have low bioaccessibilities;they are often emulsified to overcome these limitations. This study investigated the impact of various emulsifiers (ethyl lauroyl arginate (LAE);Tween 80;and sodium dodecyl sulfate (SDS)) on the physicochemical properties and in vitro digestibilities of L/Z-fortified oil-in-water emulsions. Droplet aggregation and creaming extents were dependent on the emulsifier type. The zeta-potentials of emulsions stabilized by LAE, Tween 80, and SDS were + 87, - 26, and - 95 mV, respectively. SDS-stabilized emulsion had the smallest particles, while the particle sizes for the LAE- and Tween 80-stabilized emulsions were larger and not significantly different. The rates of L/Z degradation were sensitive to the emulsifier type and to heat, not to light. The L/Z bioaccessibility was the highest for the Tween 80 emulsion. Surfactants should therefore be carefully selected to optimize L/Z physicochemical stability and bioaccessibility in emulsions.

关键词： Whole quinoa flour   Pearled quinoa flour   Physicochemical properties   Bioactive compounds   Antioxidant capacity  

摘要： ABS T R A C T This work aimed to evaluate the effect of pearling on the physicochemical properties, bioactive compound contents, and antioxidant capacity of quinoa flour. Three different varieties of whole quinoa flour and corre-sponding pearled flour were tested. Compared with pearled flour, whole flour had a higher water solubility index, swelling power, and water and oil absorption capacity;lower pasting temperature;and higher setback. The phenolic, flavonol, and saponin contents of quinoa flour were significantly decreased after pearling treat-ment. Moreover, liquid chromatography -mass spectrometry (LC-MS) was used to identify and quantify the phenolic composition. Most of the phenolic compounds were higher in whole flour than in pearled flour. The antioxidant capacity of quinoa flour was reduced after pearling. The high correlations were also found between the bioactive compound contents and properties of quinoa flour.

关键词： alkaline   salt   enzyme-assisted extraction   SDS-PAGE   sesame seed meal   TD-NMR relaxometry  

摘要： Sesame seed is mostly utilised for its oil but also the waste of the oil processing;the seed meal has also significant potential to be used as an alternative protein source. In this study, the goal is to produce sesame seed protein by using three different techniques;alkaline, salt and enzyme-assisted extraction. A comprehensive physicochemical characterisation of the extracts was performed. Total and soluble protein contents, emulsification activity & emulsion stability, FTIR spectroscopy, hydration behaviour and gelling ability experiments by TD-NMR were conducted for all extracted proteins. Also, SDS-PAGE experiments were performed to observe the effect of extraction conditions on protein folding. Overall, the aqueous phase of enzyme-assisted extracted proteins (E-ACP) had the highest protein content and solubility, which resulted in other improved physicochemical properties. Salt extracted samples were 'salted-out', therefore, had poor physicochemical properties. TD-NMR experiments further confirmed the solubility and gelling ability results by measuring the change in the T-2 spin relaxation times. Additionally, FTIR spectroscopy confirmed the most critical peaks for the proteins;Amide I (C=O stretching) and Amide II (N-H bending). In summary, depending on the physicochemical property of interest, different extraction methods yielded proteins with different properties.

关键词： amyloid fibrils   emulsifying salt   protein-protein interactions   transmission electron microscopy  

摘要： The effects of varying the concentration of pentasodi-um triphosphate (PP) emulsifying salt [0, 0.6, 1.2, 1.5, and 1.8%, plus 0.9% of a mixture of citric acid (CA) and disodium phosphate (DSP) to adjust cheese pH to 5.85] on rheological, textural, physicochemical, and microstructural properties were studied in a processed cheese model system containing-20% micellar casein concentrate,-20% sunflower oil, and-59% water. Spe-cial emphasis was placed on the unique casein fibrils recently described in a comparable processed cheese model system. Our results show that during processing (90 degrees C, 17.37 rpm over 270 min) the apparent viscosity increased more and faster for formulations containing higher concentrations of PP, in analogy to the so-called creaming reaction, a general thickening of the molten cheese mass with prolonged processing. We found that 1.2% PP (plus 0.9% CA-DSP) appeared to be the threshold for the creaming reaction to take place. With increasing PP concentrations, cheese hardness increased in a sigmoidal fashion, and insoluble (protein-bound) calcium concentration decreased exponentially. Light micrographs of samples taken at the end of processing indicated initially large and dense casein aggregates within the matrix that disappeared with higher levels of PP, in parallel with the development of a finer emul-sion. With transmission electron microscopy analysis on the same samples, the highly complex restructur-ing of the casein matrix was evident;casein fibrils had formed de novo at the periphery of the loosening casein aggregates. With higher levels of PP, amorphous areas were observed in place of the dense casein aggregates that appeared progressively void of protein, whereas fibril concentration increased throughout the rest of the matrix. Fibrils progressively attached to the surface of fat globules, thereby emulsifying them. Reverse-phase HPLC analysis of insoluble and soluble fractions indi-cated Kappa-casein to be the most likely constituen

关键词： Diabetes mellitus   Dipeptidyl peptidase-4   Hex 6   3   Maestro Schrodinger   molecular docking   organosulphur compounds   toxicity  

摘要： Diabetes mellitus (DM) is a significant common metabolic disorder seen all over the world. In 2020, according to the International Diabetes Federation (IDF), out of 463 million people who have diabetes all over the world, 77 million belong to India. As per the statistical prediction, the affected numbers are probably expected to rise to 642 million by 2040. The commercially available anti-diabetic drugs in the market include metformin, sulphonyl urea, meglitinides, miglitol, acarbose, biguanides, and thiazolidinediones cause side effects like hypoglycaemia, dizziness, liver cell injury, digestive discomfort, neurological defects, etc. Hence, bioactive organosulphur based functional ligands are chosen in this study to arrive at a newer drug for DM. In this work, in silico analysis of organosulphur molecular descriptors like physicochemical properties, solubility, drug score, and toxicity predictions are evaluated using OSIRIS and Toxtree freeware. The essential parameters for discovering drugs for biopharmaceutical formulations viz the solubility of drugs and toxicity have been calculated. The protein target Dipeptidyl peptidase DPP4 (PID: 2RIP) was docked against energy minimised sulphur compounds using Hex 6.3. The results indicate that the drug likeliness of the molecule 4, that is, N-[(3,3-dimethyl piperidin-2-yl) methyl]-4-ethyl sulphonyl aniline is active with decreasing binding energy score (-212.24 Kcal mol(-1)) with no toxicity and also few sulphur compounds are active against diabetes compared to standard drug metformin (-158.33 Kcal mol(-1)). The best drug-like ligand N-[(3,3-dimethyl piperidin-2-yl) methyl]-4-ethyl sulphonyl aniline, was docked using commercial Maestro Schrodinger software to predict the results.

关键词： caffeine   cold brew tea   high hydrostatic pressure   storage   tea polyphenols   ultrasonic  

摘要： Effects of ultrasound combined with high hydrostatic pressure (HHP) on physicochemical properties,microorganisms and storage attributes of cold brew tea were investigated. HHP at 400 MPa/5 min/25 degrees C inactivated the total aerobic bacteria, yeast and mould in cold brewed tea prepared by static brewing (SB-tea) at 13 h/4 degrees C, ultrasonic bath (UB-tea) at 150 W/120 min/0 degrees C and ultrasonic pulveriser (UP-tea) at 600 W/40 min/0 degrees C, ensuring their microbiological safety. The results showed that there was no significant difference in the concentration of tea polyphenols between hot brewed tea prepared by 7 min/100 degrees C and cold brewed tea under different preparation conditions, while the caffeine in cold brewed tea was significantly lower (P < 0.05) than that in hot brewed tea. During the storage period of 8 days, compared with the untreated group, the cold brewed tea after HHP treatment had better microbiological safety. In addition, HHP treatment constantly maintained the tea polyphenols, pH, colour, antioxidant capacity and turbidity in cold brewed tea. The untreated and HHP-treated cold brew tea were evaluated by 20 trained volunteers. Results showed that UB-tea was more close to SB-tea than UP-tea in sensory profile, while HHP seem to maintain a good sensory profile as well. Therefore, this particular combined technology of ultrasonic bath and HHP displayed considerable potential for application in the cold brew tea manufacturing industry.

关键词： Rice flour   Low-frequency ultrasound treatment   Annealing   Thermal properties   Gel rheological properties   Biopolymers structure  

摘要： Ultrasonication (US) is a green technology used to physically modify flours to increase their industrial range of applicability. The aim of this work was to study the combined effect that dual US and annealing (ANN) treatments have on starch and protein structure of rice flour, at 20, 40, 50 and 60 degrees C. Results showed clear modifications of functional, thermal and pasting properties of flours, as well as rheological properties of gels made from them. US + ANN led to generation of small-size particles, which markedly increased the swelling power and starch damage. X-Ray Diffraction and FTIR indicated that starch crystallinity and protein secondary structure was affected by the shear forces of cavitation. The combination of US + ANN improved the crystalline structure arrangement within the starch granules, causing narrowing of the gelatinization temperature range (Delta T). Pasting viscosities were significantly decreased by ultrasonication, following an increasing trend with increasing temperature, while pasting temperature was increased, agreeing in the achievement of a thermodynamically more stable structure. The rheological properties indicated a reduction of the elastic (G') and viscous (G'') moduli after ultrasonication, as well as lower values of tan (delta), reflecting a higher predominance of elastic modulus versus viscous one than the non-sonicated flours. The rice flour's properties were found to be highly sensitive to the applied treatment conditions, showing a synergetic effect when sonicating at the highest studied temperature.

关键词： Soan River   macroinvertebrates   biomonitoring and pollutants  

摘要： In the present study, the effect of pollutants produced by human dwelling, agricultural and industrial activities on aquatic invertebrate's communities of Soan River, Pakistan was studied. Four different sites were selected on the basic of variation in microhabitat accessibility to examine the pollution in water. Samples were collected from these sites during autumn and spring. From all sites physical conditions, water samples and macroinvertebrates were collected. Conductivity and D.O didn't fallow the WHO standards in both seasons while nitrate only have high concentration in autumn at all sites. All other parameters were normal except in pH at site D of spring. Aquatic insects were collected during the studied sites which belong to 6 orders and 15 families. Gerridae, Elimidae, Hydrophilidae, Gyrinidae, Culicidae and Chironomidae were most in both seasons. Total abundance was used to estimate the quality of water at each sites. Family biotic index (FBI) showed that water had good quality on upstream stations rather than downstream station in both season. While water quality index (WQI) also shows good water quality at upstream station rather than downstream stations. This study showed that aquatic insects could provide useful bioindicators to approach the biomonitoring in relation to water physio-chemical parameters to classify compare and assess the quality of water of freshwater streams in Pakistan.