茶叶果中有价值成分的提取和应用

介绍了茶叶果中茶叶果油、棕以素、茶皂素等成分的提取主各组分在医药、农药、日用化工、化妆品、金属切削液、乳化剂等方面的应用。     

茶叶提取物在牙膏中的应用

茶叶中含有茶多酚、生物碱、糖类、氨基酸、茶色素、皂苷、氟以及维生素等多种功能成分,茶叶提取物具有抑菌抗炎、清热解毒、回甘生津、防龋抗蛀、抗过敏质和祛除烟毒等功效,已广泛应用于医药、化妆品、保健品和食品添加剂等领域。含茶叶提取物的牙膏具有抗菌消炎、预防龋齿、生津回甘和分解烟毒等作用。     

茶叶与化学

我国是最早发现和利用茶的国家,据推测早在四千年以前,我国就开始饮燕至秦汉时代已有书籍记载。现在茶已成为世界五大饮料之一,作为人们生活的必需品而进入每一个家庭。茶叶的种类与成份如何?饮茶对人体有哪些益处?哪些人不宜饮茶呢?下面作一些介绍。一、茶叶的种类与制作我国根据采制工艺和茶叶的品质以及外形把茶叶分为以下五类:1.红茶它是一种经过发酵的茶叶。例如祁江、滇江、宁江等茶叶。2.绿茶它是一种不经发酵的茶叶。如龙井、旗枪、珍眉、屯绿等。     

茶叶除室内甲醛的机理初探

目前室内甲醛污染越来越引起人们的重视,市面有各种各样的消除剂,大多数为化学消除剂,普遍存在氧化性强或产生二次污染等问题。近年人们发现茶叶对净化甲醛有一定的效果,且茶叶为纯天然物质对人体无害不产生二次污染。茶叶能消醛是因为茶叶中含有生物碱、茶多酚、氨基酸等活化成分能与甲醛反应,同时茶叶对甲醛有一定的吸附作用。     

茶资源的综合开发利用展望

中国有丰富的茶叶资源，是世界产茶大国。随着现代科学的发展，人们需要享受型、方便型、保健型的茶叶产品。作者根据茶叶生物化学、中草药学等原理，参考国内外有关研究动态和自己的工作体会，简述了茶叶深加工产品的开发和低档茶、制茶副产品的综合利用途径。认为我国丰富茶资源的综合利用潜力很大。相信祖传统的茶文化与现代科学相结合，将更加绚丽多彩、发扬光大。     

萜烯类化合物与茶叶香气

萜烯类化合物是茶叶香气的重要组成部分。分析萜烯类化合物的性质、生物合成及对茶叶香气、茶叶质量的影响,可望对茶树品种的选育及提高茶叶品质产生深远影响。     

茶叶中稀土元素含量的研究现状

本文简要概述了稀土元素的种类、用途以及茶叶中稀土元素的检验现状,阐述了茶叶中稀土元素的检测方法,主要包括分光光度法、电感耦合等离子体发射法(ICP-AES)、电感耦合等离子体发射法(ICP—MS)等,并对造成茶叶中稀土元素含量超标的原因进行初步的分析。     

茶叶中痕量铅分析方法的研究进展

综述了近年来茶叶中痕量铅分析方法的研究进展.从原子光谱法、分子光谱法、电化学分析法等方法进行了归纳和评述;展望了茶叶中痕量铅分析方法未来的研究方向和发展前景.     

废弃茶叶渣净化水体中重金属的研究进展

在对茶叶的结构和基本性质进行简单介绍的基础上,综述了茶叶渣吸附重金属离子的研究进展,包括吸附性能的研究和吸附机理的研究。并进一步介绍了茶叶渣吸附重金属离子的主要影响因素,包括溶液pH、固液接触时间、金属离子的初始浓度、吸附体系的温度等影响因素。最后对茶叶渣净化重金属污染水体的实际应用做了展望。     

茶叶中稀土元素分析方法研究进展

就近年来茶叶中稀土元素含量测定的研究技术以及茶叶的前处理方法做了综述。包括分光光度法、电感耦合等离子体质谱法(ICP-MS)、示波极谱法、电感耦合等离子体发射光谱法(ICP-AES)等分析方法,以及灰化法、和湿法消解法和微波消解法等前处理方法。     

使用茶油制取液体洗涤剂增稠剂

茶油经精炼后,与甲醇反应合成茶油酸甲酯,经高、低温两步酰胺化合成高活性物含量,即酰胺含量(88％)的茶油酸二乙醇酰胺,产率达 99％。对其增稠,去污与稳泡性能进行测定,从而得出茶油酸二乙醇酰胺具有良好的增稠性和去污力,是椰子油酸二乙醇酰胺的良好代用品,且经济价值极高。     

生物法提取纯天然茶籽油联产茶皂素工艺研究

探讨了生物法提取纯天然茶籽油联产茶皂素的工艺,选择碱性蛋白酶对油茶籽仁进行酶解,经三相离心,茶籽油的提取率高达95％。所得产品属于纯天然高级健康食用植物油,各项指标均符合国家标准。通过膜分离技术可得到具有高生物活性的天然茶皂素,且纯度高达90%。     

茶油的精制方法及应用

茶油具有“东方橄榄油”的美称,其物理化学性质与橄榄油相似,其脂肪酸组成和甘油三酯结构与橄榄油相同,还含有橄榄油所没有的特定生理活性物质如山茶苷、山茶皂苷、茶多酚等性质,具有丰富的营养价值和应用价值。本文主要介绍了茶油的精制方法、应用及其发展前景。     

茶油的精制及其在化妆品中的应用

研究了溶剂萃取法脱酸、吸附脱色等方法精炼茶油的工艺和条件。结果表明:①脱酸的最佳工艺条件为,以无水乙醇为溶剂,茶油与无水乙醇比1∶2.5,温度32℃,萃取3次,每次萃取时间10 min;②脱色的最佳工艺条件为:反应温度90℃,吸附剂用量3.0%,反应时间30 min。将精制的茶油加入化妆品配方中,可显著提高产品的防晒功效。     

Interesterification of tea seed oil and its application in margarine production

Blends of hydrogenated and nonhydrogenated tea seed oil (Lahijan variety) (30:70, w/w) were chemically interesterified at 60, 90, and 120°C for 30, 60, and 90 min in the presence of 1% (w/w) NaOH. Physicochemical properties of the products were compared with those of the noninteresterified mixture. Statistical comparison of m.p., iodine values (IV), and solid fat contents (SFC) showed that the sample having the highest ranking was interesterified at 120°C for 30 min. The sample was used as a hardstock (40%), with liquid tea seed oil and sunflower oil (ratios of 100:0, 80:20, 60:40, 40:60, 20:80, and 0:100) as, a softstock (60%) for production of table magarine, and the properties of these margarines were compared with those of commercial ones. Samples E and D (ratio of 80:20 and 60:40 liquid tea seed oil/sunflower oil, respectively) had the lowest significant differences with commercial table margarine for physicochemical (m.p., IV, and SFC) and organoleptic characteristics, respectively. Generally, based on m.p. and SFC, margarines E and D were classified as soft margarine. The trans FA content of E, D, and commercial margarines were 1.8, 1.8, and 2.2%, respectively.     

Characteristics of tea seed oil in comparison with sunflower and olive oils and its effect as a natural antioxidant

A comparison of iodine values showed that the degree of saturation of tea seed oil (Lahjan variety) was intermediate between the oils of sunflowerseed (Fars variety) and olive (Gilezeytoon variety), and the saponification values of these three oils were similar. Tea seed oil consisted of 56% oleic acid (C18∶1), 22% linoleic acid (C18∶2), 0.3% linolenic acid (C18∶3), and therefore, on the basis of oleic acid, occupied a place between sunflower and olive oil. In studies at 63°C, the shelf life of tea seed oil was higher than that of sunflower oil and similar to olive oil. Tea seed oil was found to have a natural antioxidant effect, and it enhanced the shelf life of sunflower oil at a 5% level. In this study, tea seed oil was found to be a stable oil, to have suitable nutritional properties (high-oleic, medium-linoleic, and lowlinolenic acid contents), and to be useful in human foods.     

Thai Tea Seed Oil and Virgin Olive Oil Similarly Reduce Plasma Lipids: A Pilot Study within a Healthy Adult Male Population

The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day⁻¹ of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes.     

从油茶果渣、籽仁和脚料中提取茶皂素及回收脂肪酸的研究

对油茶果的深度开发作了较为详尽的研究：在尽可能提高茶油产率的同时，对榨取茶油以后的粕饼或渣，籽仁以及精制茶油后的脚料等物进行再提取或回收，从中又可得到能增值的精细化学的绿色产品——茶皂素和脂肪酸。     

Effect of plant population densities and application of growth retardants on cottonseed yield and quality

In field trials at Giza in 1986–1987, cotton cv. Giza 75 was sown at 166,000, 222,000 and 333,000 plants/ha and given foliar applications of 0, 250, 500 and 750 ppm Cycocel (chlormequat) or Alar (daminozide). As plant density increased, there was a decrease in cottonseed yield/ha, seed index, seed protein content, oil and protein yields/ha, oil refractive index, iodine value, unsaponifiable matter and unsaturated fatty acids (myristoleic, oleic and linoleic). In contrast, as plant density increased, there was an increase in oil acid value, saponification value and saturated fatty acids (caprylic, capric, lauric, tridecylic, myristic, palmitic and stearic). Application of Cycocel or Alar increased cottonseed yield/ha, seed index, seed protein content and oil and protein yield/ha, oil refractive index, iodine value, unsaponifiable matter and unsaturated fatty acids. However, there was a decrease in oil acid value and saponification value. There were no differences among application rates of either chemical on cottonseed yield/ha. The highest oil and protein yield/ha was observed with Cycocel applied at 750 ppm, followed by Alar at 250 ppm. Applying Cycocel at 250 ppm gave the highest oil refractive index and unsaponifiable matter, and the lowest acid value. Application of Alar at 250 ppm gave the highest oil iodine value and the lowest saponification value, and also at 250 or 500 ppm gave the highest oil unsaturated fatty acid composition. Interaction was positive between plant density, Cycocel and Alar and affected cottonseed yield/ha. The 166,000 plants/ha and application of Cycocel at 750 and Alar at 250 ppm are recommended for the improvement of cottonseed yield and quality.     

Fatty Acid Composition and Antioxidant Activity of Tea (Camellia sinensis L.) Seed Oil Extracted by Optimized Supercritical Carbon Dioxide

Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO(2)) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20-90 min), temperature (35-45 °C) and pressure (50-90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO(2) extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO(2) contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO(2) is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO(2) is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets.