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51.
The demand of foods with high antioxidant capacity have increased and research on these foods continues to grow. This review is focused on chlorogenic acids (CGAs) from green coffee, which is the most abundant source. The main CGA in coffee is 5-O-caffeoylquinic acid (5-CQA). Coffee extracts are currently the most widely used source to enhance the antioxidant activity of foods. Due to the solubility of CGAs, their extraction is mainly performed with organic solvents. CGAs have been associated with health benefits, such as antioxidant, antiviral, antibacterial, anticancer, and anti-inflammatory activity, and others that reduce the risk of cardiovascular diseases, type 2 diabetes, and Alzheimer’s disease. However, the biological activities depend on the stability of CGAs, which are sensitive to pH, temperature, and light. The anti-inflammatory activity of 5-CQA is attributed to reducing the proinflammatory activity of cytokines. 5-CQA can negatively affect colon microbiota. An increase in anthocyanins and antioxidant activity was observed when CGAs extracts were added to different food matrices such as dairy products, coffee drinks, chocolate, and bakery products. The fortification of foods with coffee CGAs has the potential to improve the functionality of foods.  相似文献   
52.
As important biomolecules in Camellia sinensis L., amino acids (AAs) are considered to contribute to the overall green tea sensory quality and undergo dynamic changes during growth. However, limited by analytical capacity, detailed AAs composition in different growth stages remains unclear. To address this question, we analyzed the dynamic changes of 23 AAs during leaf growth in Xinyang Mao Jian (XYMJ) green tea. Using amino acid analyzer, we demonstrated that most AAs are abundant on Pure Brightness Day and Grain Rain Day. After Grain Rain, 23 AAs decreased significantly. Further analysis shows that theanine has a high level on the day before Spring Equinox and Grain Rain, accounting for 44–61% of the total free AAs content in tea leaves. Glu, Pro, and Asp are the second most abundant AAs. Additionally, spinasterol and 22,23-dihydrospinasterol are first purified and identified in ethanol extract of XYMJ by silica gel column chromatography method. This study reveals the relationship between plucking days and the dynamic changes of AAs during the growth stage and proves the rationality of the traditional plucking days of XYMJ green tea.  相似文献   
53.
Commonly used clinical chemotherapy drugs, such as cyclophosphamide (CTX), may cause injury to the ovaries. Hormone therapies can reduce the ovarian injury risk; however, they do not achieve the desired effect and have obvious side effects. Therefore, it is necessary to find a potential therapeutic candidate for ovarian injury after chemotherapy. N-Benzyl docosahexaenamide (NB-DHA) is a docosahexaenoic acid derivative. It was recently identified as the specific macamide with a high degree of unsaturation in maca (Lepidium meyenii). In this study, the purified NB-DHA was administered intragastrically to the mice with CTX-induced ovarian injury at three dose levels. Blood and tissue samples were collected to assess the regulation of NB-DHA on ovarian function. The results indicated that NB-DHA was effective in improving the disorder of estrous cycle, and the CTX+NB-H group can be recovered to normal levels. NB-DHA also significantly increased the number of primordial follicles, especially in the CTX+NB-M and CTX+NB-H groups. Follicle-stimulating hormone and luteinizing hormone levels in all treatment groups and estradiol levels in the CTX+NB-H group returned to normal. mRNA expression of ovarian development-related genes was positive regulated. The proportion of granulosa cell apoptosis decreased significantly, especially in the CTX+NB-H group. The expression of anti-Müllerian hormone and follicle-stimulating hormone receptor significantly increased in ovarian tissues after NB-DHA treatment. NB-DHA may be a promising agent for treating ovarian injury.  相似文献   
54.
This study aimed to elucidate the responses of a novel characterized Issatchenkia terricola WJL-G4 against citric acid stress by performing physiological analysis, morphology observation, and structural and membrane fatty acid composition analysis. The results showed that under citric acid stress, the cell vitality of I. terricola WJL-G4 was reduced. The cell morphology changed with the unclear, uncompleted and thinner cell wall, and degraded the cell structure. When the citric acid concentration was 20 g/L, I. terricola WJL-G4 could tolerate citric acid and maintain the cell structure by increasing the intracellular pH, superoxide dismutase activity, and contents of unsaturated fatty acids. As the citric acid concentration was ≥80 g/L, the stress has exceeded the cellular anti-stress ability, causing substantial cell damage. The cell membrane permeability, the content of membrane lipids, malondialdehyde and superoxide anion increased, but the intracellular pH and superoxide dismutase activities decreased, accompanying the increase of citric acid concentrations. The findings of this work provided a theoretical basis for the responsive mechanism of I. terricola WJL-G4 under high concentrations of citric acid, and can serve as a reference for biological acid reduction in fruit processing.  相似文献   
55.
The objective of this study was to evaluate the effect of microwave treatment of crushed grapes on the yeast population of the must and on the development of alcoholic fermentation, as well as on the extraction of different compounds from the grapes such as polysaccharides and amino acids that can affect the organoleptic quality and stability of the wine. This study demonstrated for the first time the effect of the microwave treatment of grapes on native yeast species and their diversity, producing an increase in fermentation kinetics and a decrease in the lag phase. The microwave treatment produced a positive effect on the extraction of amino acids and polysaccharides from the grapes, resulting in significantly higher amounts of the main amino acids of the must and some major volatile compounds in the treated samples. The polysaccharides most affected by the microwave treatment were the PRAGs, the main polysaccharides liberated from grapes during the maceration.  相似文献   
56.
It is well known that organic acids (OAs) could affect the flavour of fruit juices and beverages. However, the molecular mechanism of aroma release is still unclear. In this study, the effects of citric acid (CA), L-(-)-malic acid (MA) and L-lactic acid (LA) on the release of six selected esters and their sensory perception were investigated by means of HS-GC-MS analyses and odour detection threshold determination, respectively. Meanwhile, the density functional theory (DFT) calculation was employed to explore the interaction modes between esters and OAs. HS-GC-MS analyses showed that the concentration and the type of OAs regulated the release of esters. The results were basically consistent with the detection threshold change of those esters. The DFT calculation suggested that the main intermolecular interaction was hydrogen bonds, and several esters could form a ternary ring structure with OAs through hydrogen bonds. The interactions can induce the different release behaviours of esters in OAs water solution. The number of carboxyl functional groups in OAs and the spatial conformation of esters appeared to influence the magnitude of the interaction. The above results demonstrated the mechanism of OAs affecting the release of esters and indicated a possible flavour control way by using different OAs and OA concentrations.  相似文献   
57.
58.
An VK-Z-Rohren zur Herstellung von Polyamid wurden Verweilzeitspektren mit der Methode der radioaktiven Markierung und der Methode der Indikatoraktivierungsanalyse gemessen. Die nach den beiden Methoden ermittelten Verweilzeitspektren werden miteinander verglichen. Die Übereinstimmung der Verweilzeitspektren wird durch Gegenüberstellung der statistischen Momente und durch einen Test nach Kolmogoroff-Smirnov geprüft. Es wird der experimentelle Aufwand beider Verfahren diskutiert und eine Fehlerabschätzung durchgeführt.  相似文献   
59.
Two synthetic routes to phosphonic analogues of indoprofen, a nonsteroidal anti-inflammatory drug, were developed by the cyclization of aniline 2 (method A) and by the Arbuzov reaction of corresponding alkylchloride 3 with triethylphosphite (method B).  相似文献   
60.
Aiming at the synthesis of structurally altered glycopeptides to probe multivalency effects in carbohydrate recognition, a glyco-amino acid building block was prepared, carrying a bivalent carbohydrate branching unit. This new mannosylated lysine derivative was shown to be fully suitable for solid-phase peptide synthesis.  相似文献   
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