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关键词： Panax notoginseng polysaccharides   Ultrasonic   microwave-assisted extraction   Response surface methodology  

摘要： In this study, Panax notoginseng polysaccharides (PNPS) were extracted using ultrasonic/microwave-assisted extraction (UMAE). Based on single-factor experiments, ultrasonic duration, ultrasonic power, microwave duration, and microwave power were optimized using the response surface methodology (RSM). The results indicated that the optimal extraction parameters were an ultrasonic duration of 10 min, ultrasonic power of 50 W, microwave duration of 4 min, and microwave power of 540 W, which resulted in the highest extraction rate of PNPS at 11.03 +/- 0.16%. Scanning electron microscopy images indicated that PNPS exhibited a porous and rough structure. The chemical structure of PNPS was analyzed using Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy. The molecular weight of PNPS was measured to be 4.148 x 105 Da;moreover, PNPS was found to be composed of glucose, galactose, galacturonic acid, arabinose, glucuronic acid, rhamnose, mannose, and ribose. The DPPH scavenging efficiency of PNPS (5 mg/mL) was evaluated to be 65.74%. Upon in vitro simulated saliva-gastrointestinal digestion, partly digested PNPS was obtained. In addition, differential scanning calorimetry (DSC) analysis and rheological testing results indicated that PNPS exhibited high thermal stability and favorable rheological properties. Therefore, PNPS extracted using UMAE exhibited broad application prospects for functional foods and pharmaceuticals.

关键词： shiitake mushrooms   drying techniques   drying kinetics   physicochemical properties   polysaccharide  

摘要： BACKGROUND Fresh shiitake mushrooms are rich in nutrients, but have high water content, a fast metabolism after harvest, and deteriorate extremely easily. Therefore, the drying of shiitake mushrooms has become a research direction. However, the role of different drying techniques on shiitake mushroom quality is limited. Therefore, the purpose of this study was to investigate the effect of thermal and non-thermal drying on the drying kinetics, and the physicochemical properties of the end product. RESULTS Results showed that shiitake mushroom treated with non-thermal drying (vacuum freeze-drying) had an attractive color, low shrinkage, and uniform honeycomb structure, while the drying time was the longest and not conducive to the formation of shiitake mushroom aroma. But shiitake mushroom treated with thermal drying presents an attractive fragrance. In thermal processing technology, compared with hot air convection drying (HAD), infrared hot air convection drying (IRHAD) shortens the drying time by 37.5%, and had the highest oxidation resistance, polysaccharide content and the lowest color change. Relative-humidity drying (RHD) samples had the lowest shrinkage compared with other thermal processing technology. The five polysaccharides exhibited similar preliminary structural characteristics, but the polysaccharides obtained by IRHAD have the highest antioxidant properties. CONCLUSION These results showed that compared with thermal drying technology, non-thermal drying technology is not suitable for shiitake mushroom processing. In thermal processing technology, IRHAD is a potential drying method to obtain high-quality dried shiitake mushrooms and shiitake mushroom polysaccharide (SMP). However, it is necessary to increase the pretreatment technology to achieve the attractive appearance of non-thermal drying technology. (c) 2021 Society of Chemical Industry.

关键词： Amidine   pK(a)   logD   EPSA   Alzheimer's   BACE1  

摘要： A common challenge for medicinal chemists is to reduce the pK(a) of strongly basic groups' conjugate acids into a range that preserves the desired effects, usually potency and/or solubility, but avoids undesired effects like high volume of distribution (V-d), limited membrane permeation, and off-target binding to, notably, the hERG channel and monoamine receptors. We faced this challenge with a 3,4,5,6-tetrahydropyridine-2-amine scaffold harboring an amidine, a key structural component of potential inhibitors of BACE1, the rate-limiting enzyme in the production of A beta species that make up amyloid plaques in Alzheimer's disease. In our endeavor to balance potency with desirable properties to achieve brain penetration, we introduced a diverse set of groups in beta position of the amidine that modulate logD, PSA and pK(a). Given the synthetic challenge to prepare these highly functionalized warheads, we first developed a design flow including predicted physicochemical parameters which allowed us to select only the most promising candidates for synthesis. For this we evaluated a set of commercial packages to predict physicochemical properties, which can guide medicinal chemists in their endeavors to modulate pK(a) values of amidine and amine bases. (c) 2021 Elsevier Masson SAS. All rights reserved.

关键词： Prosomillet bran   Lactic bacteria   Soluble dietary fiber   Physicochemical property   Functional property  

摘要： Prosomillet bran was fermented with lactic bacteria and the changes of the structure and physicochemical and functional properties of its soluble dietary fiber (SDF) were investigated. Results showed the yield of SDF was increased from 4.2% to 7.6% after fermentation, and the odor intensity and flavor characteristics were also significantly changed. SEM and FTIR assay indicated that the microstructure after fermentation became looser and more porous, and both of UF-SDF and F-SDF had characteristic absorption peaks of polysaccharides. Fermentation also reduced the crystalline area and thus affected the thermal stability of SDF by X-ray diffraction and thermal analysis. In addition, the physicochemical and functional properties such as solubility, water and oil holding capacity, swelling capacity, nitrite, sodium cholate and cholesterol adsorption capacity were improved as well. The phenolic content and free radical scavenging capacity also increased significantly. The above results showed that F-SDF could be applied as a functional ingredient in food industry.

关键词： rice (Oryza sativa L   )   salinity stress   salinity tolerance   grain quality   starch   physicochemical property  

摘要： BACKGROUND Rice yield and grain quality are highly sensitive to soil salinity. Distinct rice genotypes respond to salinity stress differently. To explore the variation in grain yield and grain trait adaptation to moderate, reproductive-stage salinity stress (4 dS/m electrical conductivity), four rice cultivars differing in degrees of vegetative salt tolerance, including Pokkali (salt-tolerant), RD15 (moderately salt-tolerant), KDML105 (moderately salt-susceptible) and IR29 (salt-susceptible), were examined. RESULTS Grain fertility and 100-grain weight of RD15, KDML105 and IR29, as well as grain morphology of KDML105 and IR29, were significantly disturbed. Interestingly, grain starch accumulation in RD15 and KDML105 was enhanced under stress. However, only RD15 showed changes in starch physicochemical properties, including increased granule diameter, decreased gelatinization peak temperature (T-p) and decreased retrogradation onset temperature (T-o). Notably, Pokkali maintained productivity, grain quality, and starch properties, while the grain quality of IR29 remained unchanged under salinity stress. Multivariate analysis displayed clear separation of productivity, grain morphology, and starch variables of RD15 in the salt-treated group relative to the control group, suggesting that it was the cultivar most impacted by salt stress despite its moderate salt-tolerance at vegetative stage. CONCLUSION Our results demonstrate specific salinity responses among the rice genotypes, and suggest discrepancies between degrees of salt tolerance at vegetative stage versus the ability to maintain both grain quality and starch properties in response to salinity stress imposed at reproductive stage. (c) 2021 Society of Chemical Industry.

关键词： Peanut oil   Roasting   Phospholipids   Oxidized fatty acids   Polycyclic aromatic hydrocarbons  

摘要： Roasting before oil extraction improves qualities of vegetable oils. Herein, the physicochemical properties (color, conjugated dienes and trienes), chemical composition (carotenoids, phospholipids, Maillard reaction products, polycyclic aromatic hydrocarbons, 3-monochloropropane-1,2-diol esters, glycidyl fatty acid esters, and oxidized fatty acids), and antioxidant activities of oils extracted from unroasted peanut kernels and roasted ones in dry air (160 degrees C, 170 degrees C, 180 degrees C, and 190 degrees C for 10, 15, 20, 25, and 30 min at each temperature) were systematically investigated and compared. The results indicated that the a* value, carotenoids and antioxidant activities increased significantly (p < 0.05) while the L* and b* values decreased obviously (p < 0.05) with the increase of roasting temperature and time. Conjugated dienes and trienes, oxidized fatty acid, and phospholipids including phosphatidylcholine and phosphatidylethanolamine increased firstly and then decreased during roasting (p < 0.05). Maillard reaction products, polycyclic aromatic hydrocarbons increased significantly (p < 0.05) with roasting. However, roasting had no evident influence on the formation of 3-monochloropropane-1,2-diol esters and glycidyl fatty acid esters. The oils from roasted peanut kernels at 190 degrees C for 30 min had significantly higher oil quality and antioxidant activities.

关键词： Edible coating   Deep-fried chicken   Sweet potato starch   Thyme essential oil   Oleogel  

摘要： In this study, oleogels were prepared by mixing canola oil and two concentrations of carnauba wax at 5 g/100 g and 10 g/100 g. Chicken breast samples were deep-fried in either canola oil or oleogels (5 or 10 g/100 g (w/v)) for 3-4 min at 177.7 degrees C. Fried and raw samples were dipped in sweet potato starch edible coating formulated with thyme essential oil (TEO) at 0, 2, and 4 g/100 g (v/v) concentrations. Consequent to drying, coated samples were bagged and stored in a refrigerator at 4 +/- 1 degrees C for 8 days. Oleogel-fried samples had significantly lower fat contents than canola oil-fried samples but oleogelation did not improve the oxidative stability of the fried chickens. However, the incorporation of 2 g/100 g TEO into edible coating offered better oxidative stability in the oleogel-fried samples (P < 0.05) up to 4 days. There were no significant differences in texture, coating pickup, and color properties among treatments (P > 0.05). The edible coating did not alter water activity and pH values in raw samples. However, coated samples activated with TEO had lower counts of the microorganisms.

关键词： Orally disintegrating films   Catechin   13-cyclodextrin complex   Physicochemical properties   Functional properties   Limited release  

摘要： The study aimed to develop pre-gelatinized starch-based orally disintegrating films (ODFs) containing catechin/ 13-cyclodextrin (CAT/13-CD) complex and to evaluate the influence of the complex on the physicochemical properties of the ODFs. SEM images showed that a compacter and more homogeneous ODFs were formed due to interactions between starch matrix and CAT/13-CD. FTIR spectra demonstrated that the interactions between starches or starch and CAT/13-CD were enhanced by hydrogen bonds. Thermal stability of ODFs was improved by incorporating CAT/13-CD, its peak decomposition temperature was enhanced from 310.74 to 321.83 degrees C. Tensile strength was increased from 11.597 +/- 0.153 to 22.172 +/- 0.752 MPa, while elongation at break decreased by from 11.233% +/- 1.079% to 3.633% +/- 0.058%. The prepared ODFs have an acceptable in vitro disintegration time, which were between 9.03 +/- 0.79 s and 42.23 +/- 1.76 s. Antimicrobial test showed that ODFs incorporating CAT/13-CD inhibited the growth of S. aureus and S. mutans successfully. The limited release of CAT molecules from the ODFs was also found. In addition, the ODFs have excellent antioxidant capacity. Its antioxidant activity remained at around 70% after 28 days of storage. The study indicated that the combination of ODFs and 13-CD complex have a high potential for the delivery of natural active ingredients.

关键词： oil palm biomass   protein content   degree of hydrolysis   functional groups   thermal stability  

摘要： BACKGROUND The oil palm tree produces 90% of wastes and the limited usage of these wastes causes a major disposal problem in the mills. Nevertheless, these by-products have a large amount of nutritional components. Thus, the present study aimed to determine the physicochemical and functional properties of protein hydrolysates (PH) from oil palm leaves (OPL) extracted using different concentrations of Alcalase (0-10%) at 2 h of hydrolysis time. RESULTS Fourier transform infrared spectral analyses showed that the enzymatic hydrolysis altered functional groups of OPL where a secondary amine was present in the PH. Changes were also observed in the thermal stability where the enthalpy heat obtained for PH (933.93-1142.57 J g(-1)) was much lower than OPL (7854.11 J g(-1)). The results showed that the PH extracted by 8% Alcalase exhibited absolute zeta potential, as well as a high emulsifying activity index (70.64 m(2) g(-1) of protein) and emulsion stability index (60.58 min). Furthermore, this PH showed higher solubility (96.32%) and emulsifying properties compared to other PHs. It is also comparable with commercial plant proteins, indicating that 8% Alcalase is an optimum concentration for hydrolysis. CONCLUSION In summary, the physicochemical and functional properties of PH extracted from OPL showed good functional properties, suggesting that it can be used as an alternative plant protein in food industries. (c) 2021 Society of Chemical Industry.

关键词： Beer  

摘要： Main by-product of white wine production is white grape pomace (WGP). It has attracted attention of food scientists, because it possesses high concentration of nutrients and bioactive substances. In this study, WGP was added to the beer after primary fermentation in two different concentrations (10% w/w and 20% w/w) and two different pretreatments (pasteurised and unpasteurised) to determine, whether the most abundant waste from white wine industry could be used to modify the volatilome and phenolic content of the beer. The addition of white grape pomace increased the concentration of phenolic compounds in all of the tested beers (from 321.584 mg gallic acid equivalent (GAE)/dm(3) to 501.459 mg GAE/dm(3)). Antioxidant activity of the beers with addition of WGP (tested with the ABTS(+.), DPPH center dot and FRAP assays) also increased. The composition of volatiles in beers changed as WGP was added. The most significant difference was in the concentration of acetaldehyde beers with WGP added had 4-7 times lower acetaldehyde content (17.425-31.425 mg/dm(3)) than the control sample (134.050 mg/dm(3)).