超声波辅助提取石崖茶总黄酮工艺优化

应用正交试验方法对石崖茶总黄酮提取工艺进行优化。结果表明:各因素对总黄酮提取量影响大小依次为:料液比超声温度超声时间乙醇浓度。超声波辅助石崖茶总黄酮提取工艺最佳条件为料液比1∶40(g/m L)、乙醇浓度70%、超声时间30 min、超声温度55℃,此条件下总黄酮提取率为30.3%。采用该工艺测定广西昭平、桂平和金秀三个产地的石崖茶总黄酮含量,结果昭平石崖茶总黄酮含量最高,为30.4%。     

探究暴马丁香叶中总黄酮的超声提取工艺

为充分利用暴马丁香,以暴马丁香叶为材料,利用超声辅助提取法对暴马丁香叶的径粒大小、液料比、乙醇浓度、超声时间进行了研究。结果表明:径粒大小为过80目筛时,提取暴马丁香总黄酮含量最高为11.078mg/g,液料比为1∶15时暴马丁香总黄酮提取含量最高为23.653mg/g,乙醇浓度为70%时暴马丁香总黄酮提取含量最高为26.116mg/g,超声时间为20min时暴马丁香总黄酮提取含量高为26.158mg/g,正交实验优化得到的最佳工艺条件为径粒大小为60目,液料比为1∶15,乙醇浓度为80%,超声时间为40min。     

千层塔全草总黄酮提取工艺的优化

为了优化千层塔全草中总黄酮的提取工艺。采用索氏提取方法,以总黄酮提取率为考察指标,通过单因素试验确定各因素对提取工艺的影响,正交试验确定最佳提取工艺。结果表明：影响千层塔总黄酮提取效率的主次因素依次为：乙醇浓度＞温度＞提取时间＞料液比。千层塔中总黄酮最佳提取工艺为：乙醇浓度60％、提取时间130 min、提取温度85 ℃、料液比（g/mL）1 ∶ 35,千层塔中总黄酮提取率为1.262 6％。     

微波辅助提取豆粕中大豆异黄酮

采用微波辅助提取豆粕中大豆异黄酮,通过单因素实验和正交实验研究了微波火力、乙醇浓度、料液比、微波时间对大豆异黄酮提取率的影响.结果表明,在试验条件范围内各因素对大豆异黄酮提取率的影响主次顺序为:微波火力＞乙醇浓度＞料液比＞微波时间.微波辅助提取大豆异黄酮的最佳条件为:料液比1∶20(g∶mL),微波火力中高火,微波时间3 min,乙醇浓度50％.在此条件下,大豆异黄酮的提取率可达到1.2432％.     

响应面法优化枇杷花总黄酮超声波辅助提取工艺的研究

采用超声波辅助提取枇杷花中的总黄酮,研究超声波功率、乙醇浓度、提取温度、提取时间、液料比及提取次数对总黄酮提取得率的影响。根据单因素试验,选择在超声波功率80 W、一次浸提条件下优化提取工艺;采用Box-Behnken中心组合试验设计原理,设计4因素3水平试验,以响应面分析法优化乙醇浓度、提取温度、提取时间及液料比4个因素对总黄酮提取得率的影响。结果表明：当超声波功率为80 W时,枇杷花中总黄酮超声波辅助提取的优化工艺参数为：乙醇浓度47.33％、提取温度58.42 ℃、提取时间12.01 min、液料比（mL ∶ g）45.56 ∶ 1,在此条件下枇杷花总黄酮一次浸提的提取得率可达10.48％。     

响应面法优化暴马丁香枝条中紫丁香苷提取工艺

为了优化暴马丁香中紫丁香苷的提取工艺,以暴马丁香枝条为实验材料,采用超声提取法,以紫丁香苷提取率为指标对料液比、乙醇浓度、超声功率、超声时间进行单因素实验,并利用响应面法进行三因素三水平的分析,对提取条件进行优化。得到最佳提取条件为:料液比1∶20g/mL,乙醇浓度60.93%,超声功率162.05W,超声时间61.57min,该条件下紫丁香苷提取率为2.3259mg/g。为暴马丁香资源的综合利用提供参考依据。     

正交试验优化山地五月茶总黄酮的提取工艺

通过单因素试验,分析乙醇浓度、提取温度、提取时间、料液比、提取次数等对总黄酮提取率的影响,采用正交试验确定山地五月茶总黄酮的最佳提取工艺。结果表明,山地五月茶总黄酮的最佳提取条件为乙醇浓度85%、料液质量体积比1∶10、提取温度90℃,加热回流提取2.0 h,提取3次。在此条件下,测得山地五月茶总黄酮的含量为(4.548 6±0.041 5)mg/g。本研究建立了山地五月茶总黄酮的提取工艺,可为山地五月茶资源的充分利用、研究开发等提供科学依据。     

中华苦卖菜总黄酮超声提取工艺研究

目的优选中华苦卖菜总黄酮的超声波提取工艺。方法以总黄酮含量为指标,采用超声波提取方法分别考察了料液比、乙醇浓度、超声时间和超声温度对总含量的影响。结果超声提取中华苦卖菜总黄酮的最佳条件为料液比为料液比为1:50,乙醇体积分数为70%,超声温度45℃,超声时间50 min。结论采用超声波提取技术提取中华苦卖菜总黄酮,具有提取时间短,提取效率高,可较好地用于中华苦卖菜总黄酮的提取。     

微波提取天胡荽总黄酮的研究

使用不同乙醇浓度、微波时间、微波功率、料液比等对天胡荽植物体全草中总黄酮微波提取率的影响进行探讨,结果表明单因素实验中最佳乙醇浓度为70％、最佳微波时间为20S、最佳微波功率为360W、最佳料液比为1：50。通过正交设计实验,得出总黄酮提取的最佳提取条件为：70％乙醇,微波时间20s,微波功率180w,料液比1：40,可获得天胡荽总黄酮最高提取率为1．883％。     

低温豆粕中大豆皂甙的微波提取工艺优化

为优化提取和纯化低温豆粕中皂甙的加工工艺,采用微波法提取低温豆粕中的大豆皂甙,通过单因素试验和正交试验研究了微波火力、乙醇浓度、料液比、微波时间对大豆皂甙提取率的影响.结果表明:在试验条件范围内各因素对大豆皂甙提取率影响的主次顺序为微波时间＞微波火力＞乙醇浓度＞料液比;在微波火力为中高火、微波时间2.5 min、乙醇浓度60％、料液比1:25(g:mL)的条件下得到最优工艺条件,此时大豆皂甙的提取率为0.640％.     

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.     

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.     

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.     

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.     

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).     

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).     

Pharmacokinetics of Marine-Derived Drugs

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.