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1.
茶多糖(Tea Polysaccharide,TPS)是茶叶中一类具有生物活性的水溶性复合多糖总称,具有多种生物活性,对人体具有重要生理功能,其降血糖和防治糖尿病作用尤为突出。本文对近年来茶多糖的提取、分离方法和生理功能等方面的研究进展进行综述,以期为其下一步研究与开发利用提供参考。  相似文献   

2.
茶多酚具有抗氧化、抗肿瘤、抗辐射等多种生物活性,与环糊精、黑木耳多糖或壳聚糖等多种多糖作用后,功能活性增强,但相互作用的过程与机理尚不明确。因此,对茶多酚与多糖的结构及其相互作用的研究显得尤为重要。近几年,关于茶多酚与多糖之间相互作用的研究日益增多,本文介绍了茶多酚和多糖的分类及结构,概括了多糖与茶多酚之间的相互作用类型、影响因素及研究方法,针对二者之间的相互作用对茶多酚功能特性的影响进行了综述,为后续研究二者与其他活性物质相互作用以及功能特性变化等方面提供参考。  相似文献   

3.
绿茶具有显著的保健功能,近年来受到越来越多的学者关注.本文简要综述绿茶及其提取物在增加食品风味、食品护色和保鲜、脱臭、食品去毒、合成食品包装材料、形成凝胶、回收蛋白酶等方面的应用.  相似文献   

4.
茶多糖的提取及分离纯化研究进展   总被引:2,自引:0,他引:2  
茶多糖是从茶叶提取出来的植物多糖,具有多种生物活性,近些年已发展成为茶学领域的一个新的研究热点.本文主要综述了近年来茶多糖提取、分离纯化等方面的研究进展,并对未来的研究方向和发展前景进行了展望,以期为茶多糖的研究与开发提供理论依据.  相似文献   

5.
可食膜保鲜剂在蜜柚上的应用研究   总被引:1,自引:0,他引:1  
通过研究澳大利亚可食膜保鲜技术和方法在蜜柚上的应用,筛选出最佳的膜配方和保鲜方法,用配方2(过滤水+杀菌剂+膜剂)涂膜处理后结合低温冷藏保鲜,贮藏期为120天后好果率达到90%以上,可食率高于75%。利用可食性保鲜膜涂膜,为改变原有的热塑包装保鲜提供新的参考方案。  相似文献   

6.
我国茶叶产量世界第一,茶资源十分丰富。茶多糖作为从茶叶、茶花和茶籽中提取出来的一种复合多糖,因具有抗糖尿病、抗氧化、抗肿瘤、增强免疫和调节肠道菌群等多种生物活性引起极大关注,并被广泛应用于保健品、化妆品和医药等领域。文章对茶多糖的提取纯化、化学结构、功能活性及产业化应用进行综述,以加强对茶多糖的认知,推动茶叶健康产业发展。  相似文献   

7.
卫赛超  谢晶 《热带作物学报》2022,43(9):1907-1917
为探究不同纳他霉素添加量(0.05、0.1、0.2 g/kg)对壳聚糖/玉米醇溶蛋白可食性复合涂膜保鲜芒果(N1、N2、N3)效果的影响,以壳聚糖/玉米醇溶蛋白复合涂膜处理为阳性对照(CZ),以清水处理为空白对照(CK),研究芒果在低温(13℃)贮藏30 d过程中转黄率、病情指数、果肉色泽特征、生理生化、品质变化及抗氧化能力。结果表明:CK组贮藏期仅为24 d,涂膜处理可至少将芒果贮藏期延长6 d;纳他霉素涂膜组推迟了芒果呼吸高峰的出现,N3组的呼吸峰值最低;与CK组相比,N3组在24 d的转黄率和病情指数分别降低了45.83%和44.17%;N3组显著抑制了自由水分、果实质量和硬度的下降,保持了可溶性固形物、可滴定酸和维生素C等营养物质含量;同时,涂膜组的POD和SOD含量均显著低于CK组,果肉总色差和相对电导率上升得到了抑制,说明复合涂膜处理有效延缓了芒果衰老进程,保持了更好的果实新鲜度。综上,添加纳他霉素的壳聚糖/玉米醇溶蛋白可食性复合涂膜可显著提升对芒果的保鲜效果,添加量为0.2 g/kg的纳他霉素复合涂膜效果更佳。纳他霉素复合涂膜在水果保鲜的应用中具有良好的前景。  相似文献   

8.
食品安全事件影响国民健康,让食品产业链的生产及交换过程透明化,是解决食品安全问题重要的第一步。基于食品追溯制度,阐述食品管理与追踪追溯的关联,通过架构分析,探究区块链技术在食品追踪追溯中应用的可行性及其应用范围,进行区块链技术的适用性原则探讨,在此基础之上提出区块链技术可能在食品成分溯源、下架召回、保鲜期限和生产规范等方面提供助益。  相似文献   

9.
茶多酚是绿茶中重要的生物活性物质,具有抗氧化、抗肿瘤、抗菌、降血糖血脂以及抗衰老等多方面的生物活性作用,广泛应用于医疗保健、化工、食品等领域,成为近年来研究的热点。本文就近年来茶多酚生物活性以及目前研究存在的问题进行综述,并对其发展前景进行了展望。  相似文献   

10.
含茶多酚的大豆分离蛋白涂膜对甜樱桃保鲜效果的影响   总被引:2,自引:0,他引:2  
将天然抑菌抗氧化物质茶多酚添加到大豆分离蛋白中制成复合涂膜液,以感官指标、硬度、腐烂指数、可溶性固形物和VC含量为质量指标定期取样分析测定,研究所制成的涂膜液在室温条件下对甜樱桃的保鲜效果。结果表明,含茶多酚的大豆分离蛋白复合涂膜液能较好地保持贮藏樱桃的感官品质,降低甜樱桃在贮藏期间的腐烂率,延缓果实硬度、VC和可溶性固形物含量的下降,从而延长果实的保鲜期。5%的大豆分离蛋白溶液中添加200mg/kg茶多酚制得的涂膜液保鲜效果显著,和对照相比,可将甜樱桃的室温保鲜期从2d延长至8d。  相似文献   

11.
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.  相似文献   

12.
13.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

14.
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions.  相似文献   

15.
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn.  相似文献   

18.
Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC2 and BC3 substitution into ssp.andigena cytoplasm and BC2 and BC2 substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.  相似文献   

19.
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.  相似文献   

20.
Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.
Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O2:1% CO2, 2% O2:6% CO2, 2% O2:12% CO2, 6% O2:6% CO2). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.
  相似文献   

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