苦丁茶酶解浸提方法的研究

通过添加外源酶（纤维素酶、果胶酶和木瓜蛋白酶）浸提苦丁茶,分析了苦丁茶浸提液中化学成分含量的变化,以及单一酶和酶组合间的比较分析,得出苦丁茶的最适酶解浸提方法为时间40βmin、温度50℃、pH值5.5和纤维素酶浓度0.2％。     

仙草多糖提取工艺条件优化研究

采用水提法浸提仙草，以仙草多糖的提取率为指标，研究料液比、浸提温度、浸提时间及浸提次数4个因素对其提取率的影响，并从中挑取合适的因素水平进行正交试验及SPSS分析。结果表明：在这4个因素中，对提取率影响最大的因素是浸提温度，然后是浸提时间，再次是料液比，最后是浸提次数；在料液比1:60、温度100 ℃、浸提时间3 h的最优条件下，仙草多糖的提取率高达17.89 %，此时仙草多糖的含量为44.13 %。     

食用菌浸提工艺及其复合饮料的研究

以多糖浸出量为指标,进行银耳、竹荪、香菇、姬松茸的浸提工艺优化,获得最佳浸提工艺参数为:银耳浸提料水比1∶100,温度90℃,浸提时间3 h;竹荪浸提料水比1∶110,温度100℃,浸提时间3 h;香菇浸提料水比1∶80,温度100℃,浸提时间3 h;姬松茸浸提料水比1∶100,温度100℃,浸提时间3 h.经复合饮料...     

普洱茶中α-淀粉酶抑制剂的提取工艺研究

本文研究了普洱茶中α-淀粉酶抑制剂的提取工艺。以水为溶剂，选取浸提时间、固液比和浸提温度三个因素做单因素实验，然后通过正交实验方法确定最佳提取工艺。结果表明，普洱茶中α-淀粉酶抑制剂的最佳提取工艺条件为浸提时间为1h，固液比1：20，温度为93．5℃。经反复实验，结果稳定，此工艺可为进一步研究普洱茶淀粉酶抑制剂及深入开发利用普洱茶提供一定的理论依据。     

‘红仙蜜’火龙果果皮红色素的提取工艺研究

采用水浴浸提火龙果果皮红色素,通过单因素和正交试验研究浸提液乙醇浓度、pH值、水提温度和水提时间对火龙果果皮红色素提取效果的影响。结果表明,影响火龙果果皮红色素提取的主要因素及次序为:浸提温度、提取液浓度、pH值、浸提时间。试验范围内,火龙果果皮红色素最佳提取工艺条件为:浸提温度30℃、浸提时间45 min、pH值为6.5和乙醇浓度40%。     

普洱茶主要氧化产物提取条件的优化及其抗氧化活性分析

以普洱茶为原料,研究溶剂pH值、浸提温度、时间、料液比对茶褐素（TBS）提取率的影响。结果表明,溶剂pH值、浸提温度、时间、料液比等都显著影响TBS的浸提效果,其中料液比、浸提温度、浸提时问达到了极显著水平,各因素影响效果的重要眭依次为：料液比〉浸提温度〉浸提时间〉溶剂pH值。同时得到茶褐素浸提的优化条件为：温度100℃,溶剂pH=7,料液比1：30,时间20min。茶褐素抗氧化活性分析结果显示,其抗氧化活性优于普洱茶水提物。     

正交设计法研究花生粗脂肪含量测定方法

以石油醚为浸提剂,选择浸提温度、浸提时间和淋洗时间3个因素,根据L9(34)正交设计表,用FOSS2050型脂肪测定仪对索氏提取法测定花生粗脂肪含量进行了研究。结果表明,淋洗时间对花生粗脂肪含量测定结果影响最大,其次是浸提时间;花生粗脂肪含量测定的最佳提取方案为浸提温度120℃、浸提时间80 min、淋洗时间30 min。     

茶饮料浸提工艺参数的研究

通过对绿茶饮料制造过程中浸提工艺参数的研究发现，浸提温度（T）、浸提时间（t）及茶叶浓度（C）不同程度地影响成品的滋味、色泽、香气。利用正交实验法得到当T为90℃，t为3min，C为1.5％时，产品的感观品质最佳，验证实验进一步证明了上述结论。茶饮料浸提工艺参数的研究@于敏     

利用固定化纤维素酶酶解夏季绿茶工艺的研究

以壳聚糖作为载体,戊二醛为交联剂制备固定化纤维素酶,对夏季绿茶进行酶解。通过正交实验得到优化工艺：在1.0g茶叶中,以茶水比1︰20,加入1.0g固定化纤维素酶,55℃下恒温浸提50min。与传统高温水提法所得茶汤相比,以此工艺条件浸提所得茶汤中茶多酚、氨基酸、咖啡碱含量有所提高,酚氨比有所下降,连续提取7批次茶叶,固定化纤维素酶的相对酶活力仍保持80%以上。     

基于熵权法的响应面优化罗望子果肉活性物质酶法浸提工艺

为优化罗望子果肉浸提工艺,提供罗望子果肉加工与罗望子果肉活性物质研究的理论依据。本研究以多糖提取率、原料利用率、总酚提取率和总黄酮提取率为响应值,以熵权法赋权,通过响应面法对罗望子果肉纤维素酶法浸提工艺进行优化,并对其浸提过程中浸提液的抗氧化活性变化进行了研究。结果发现罗望子浸提液对于OH?清除能力极强,均大于190 mg/100 mL,OH?清除能力和ABTS ⁺?清除能力对提取条件的变化敏感。考虑实际情况得到最佳提取工艺的提取时间为51 min,料液比为1:10.9（g/mL）,纤维素酶添加量为质量比1.5‰,在此条件下,罗望子果肉多糖提取率为12.66%,原料利用率为88.24%,总酚提取率为4.79‰,总黄酮提取率为4.38‰,与理论预测值接近。该模型能较好预测罗望子果肉的浸提工艺,可以用于保健饮料加工。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

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.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Novel food and non-food uses for sorghum and millets

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.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.     

Recent Modifications of Chitosan for Adsorption Applications: A Critical and Systematic Review

Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).