绿茶酒液态发酵工艺参数的优化研究

以信阳毛尖为主要原料,对影响其液态发酵工艺过程的4个因素进行单因素试验,并设计L₉（3⁴）正交优化试验,对其结果进行直观分析,确定毛尖茶酒最佳液态发酵工艺条件为：接种量0.3‰,蔗糖添加量180g/L,pH4.6,温度24℃,发酵时间12d。采用该条件生产的绿茶酒不仅具有茶香和酒香,酸甜适口,且富含功能成分,是一种老少皆宜的保健饮品。     

茶树花冰茶的研制

以茶树干茶花为原料,通过浸提试验和3因素3水平正交试验确定茶树花汁的最佳浸提条件和茶树花冰茶的最佳配方。结果显示,当固液比为1：60时,茶树花汁中茶多酚含量最高。低温萃取时,茶树花汁呈透明的土褐色,冷却后也不易产生冷后浑的现象,而高温萃取时茶树花汁颜色较深且有沉淀产生。茶树花汁的最佳浸提条件为：固液比1：60,浸提温度80℃,浸提时间5min;用茶树花汁配制茶树花冰茶的最佳配方为：     

树仔菜中多酚物质的提取工艺及其清除DPPH的抗氧化作用的研究

为研究树仔菜中多酚物质的提取工艺条件并测定其提取物清除DPPH的抗氧化活性,通过单因素试验,分析不同浸提溶剂、料液比、浸提时间、浸提温度对树仔菜多酚提取量的影响,通过正交试验确定树仔菜多酚的最佳提取条件。结果表明：提取剂为蒸馏水,料液比1∶25,提取温度30℃,提取时间8 h。提取条件下,树仔菜平均多酚提取量达到17.45 mg/g;80%甲醇树仔菜提取物对DPPH自由基清除率达到93.66%,明显高于BHT。采用正交试验法优化了树仔菜多酚提取工艺条件,提升了树仔菜多酚提取量,同时树仔菜提取物具有较好的抗氧化作用。     

浸提温度对绿茶茶汤沉淀形成的影响

比较了不同浸提温度（20~100℃）对绿茶茶汤主要理化成分及可逆与不可逆沉淀量的影响。研究结果表明,随着浸提温度的提高,绿茶茶汤固形物浓度、主要化学成分含量、可逆沉淀量及不可逆沉淀量都显著增加;浸提温度40℃及以下,绿茶茶汤沉淀量很少,且基本没有不可逆沉淀;浸提温度从40℃增加到50℃,可逆与不可逆沉淀量都有大幅度增加;浸提温度从50℃增加到90℃,茶汤固形物浓度增加不明显,但沉淀量却有较大增加。绿茶茶汤浸提温度选择低于50℃,可以大大降低沉淀量的形成。     

浓茶汁的制备工艺及其解毒作用实验研究

采用正交试验设计,以提取时间、料液比和提取温度条件为考察因素,以茶多酚含量为考察指标进行浓茶汁制备工艺优选;制备茶汁制三十六荡炮制品,测定其炮制前后的LD50,比较其毒性的变化.结果表明,浓茶汁制备方法为回流提取优于浸泡提取,三种茶叶茶多酚提取率为绿茶>黑茶>红茶;浓茶汁提取工艺为50 g茶叶加水量400 mL,提取时间为40 min,温度为95℃;三十六荡经浓茶汁炮制前后的急性毒性有差异,其毒性大小依次为红茶炮制品>原药材>绿茶炮制品.三十六荡经绿茶炮制后毒性明显降低,研究结果可为茶汁解毒提供依据.     

绿茶和白茶中茶多酚提取工艺优化及抗氧化活性比较

通过正交试验优化绿茶和白茶中茶多酚提取工艺,采用羟基自由基清除能力、DPPH自由基清除能力和总抗氧化能力评价其抗氧化活性.结果表明:绿茶中的茶多酚最佳提取工艺为超声温度60℃、料液比为1:50 g/mL、乙醇浓度70％、超声时间110 min,提取率为19.68％;白茶中的茶多酚最佳提取工艺为超声温度70℃、料液比为1:60 g/mL、乙醇浓度80％、超声时间90 min,提取率12.07％.对羟基自由基的IC50值为:绿茶76.76μg/mL、白茶101.29μg/mL、Vc 145.17μg/mL;对DPPH自由基的IC50值为:绿茶47.53μg/mL、白茶69.55μg/mL、Vc 156.12μg/mL.两种茶均具有很强的抗氧化活性,且绿茶强于白茶.     

姜汁绿茶复合饮料的研制

本文以生姜和绿茶浸提液为原料,将生姜汁和绿茶浸提液按比例调配后,加入一定比例的蔗糖和柠檬酸调味制成生姜绿茶饮品。通过单因素试验和正交试验探究姜汁添加量、绿茶浸提时的茶水比、绿茶浸提液添加量、蔗糖添加量、柠檬酸添加量对姜汁绿茶品质的影响,确定了该饮料的最佳工艺条件。结果表明,当姜汁添加量为5.0%、茶水比为1:50、茶叶浸提液添加量为60%、糖添加量为7%、酸添加量为0.12%时,茶饮料的口感最佳。     

绿茶鲜汁浸提条件研究

采用正交设计实验研究了绿茶鲜汁浸提条件对茶汁品质的影响。结果表明,随浸提温度的升高和时间的延长,茶汤固形物浸提率增加,茶汤色泽中绿度 (a) 减小,黄度 (b) 增大,茶汤明度 (L) 减小,主要生化成分增加。当茶水比达到1∶60时提取率和茶汤的冷后浑量增加不明显。最适宜的提取条件为:浸提温度50℃,时间10 min,茶水比为1∶60。     

莲子低聚糖提取工艺优化及其组分分析

采用响应面分析法对莲子低聚糖热水浸提工艺参数进行优化,探讨浸提时间（min）、浸提温度（℃）和水料比（V/W）对热水浸提莲子低聚糖得率的影响,建立提取莲子低聚糖的二次项数学模型并验证其可靠性,得到最优提取工艺参数,并采用高效液相色谱法对莲子低聚糖组分进行初步分析。结果表明：热水浸提莲子低聚糖的最佳提取工艺条件是浸提时间为66 min,浸提温度为81 ℃,水料比为80 ∶ 1,在此工艺条件下莲子低聚糖得率为8.09％。影响低聚糖提取工艺的主次因素顺序为：水料比>浸提温度>浸提时间。高效液相色谱法测定莲子低聚糖,发现莲子低聚糖由四聚糖、三聚糖和二聚糖组成。     

胡椒调味油加工工艺条件的研究

以胡椒粉和大豆色拉油为主要原料制备风味独特的食用调味油,采用正交试验分析胡椒原料粒度、浸提温度以及质量比对胡椒调味油产品品质的影响,确定最佳工艺条件:以40目胡椒粉为原料,浸提温度为130℃,质量比(胡椒:大豆色拉油)为1:6(g/g).     

Mineral composition of some traditional Mexican teas

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.     

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.     

Redox Status and Neuro Inflammation Indexes in Cerebellum and Motor Cortex of Wistar Rats Supplemented with Natural Sources of Omega-3 Fatty Acids and Astaxanthin: Fish Oil,Krill Oil,and Algal Biomass

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.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part II: Electrostatic separation of particles

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.     

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.     

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.     

<Emphasis Type="Italic">Pulque</Emphasis>, An Alcoholic Drink from Rural Mexico,Contains Phytase. Its <Emphasis Type="Italic">in vitro</Emphasis> Effects on Corn Tortilla

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.