MORPHOLOGY AND CHEMICAL COMPOSITION OF BARLEY ENDOSPERM CELL WALLS

Cell walls have been isolated from barley endosperm and found to contain a microfibrillar phase which is embedded in an amorphous matrix. The microfibrillar phase probably consists of cellulose, together with tightly bound arabinoxylan and polysaccharides rich in mannose. The matrix material is arabinoxylan (approx. 25%) and β-glucan (approx. 75%). Pectic polysaccharides are absent from the isolated cell walls. After successive removal of the matrix polysaccharides with water and 1-M NaOH, only 6% of the wall remains. The intra-cellular surfaces of the wall fragments are extensively pitted, probably as a result of adpression of starch granules into the cell wall material during endosperm development. Although polysaccharides are the major components of the cell walls, some nitrogen (less than 1%) is present. Phenolic compounds may also be wall constituents, but hydroxyproline could not be detected.     

巴西蘑菇菌丝体中抑瘤活性甾醇的分离和结构鉴定

筛选巴西蘑菇菌丝体醇提物中的抗肿瘤活性成分。巴西蘑菇深层发酵的菌丝体，在用热水提取出水溶性成分（主要是活性多糖）后，对其残渣用85％的乙醇提取，以S180荷瘤鼠为模型，对乙醇提取物进行抑瘤活性为导向的分级。先用丙酮、正己烷分步提取，再经硅胶柱层析进一步分级，并对分离出的高抑瘤活性组分，利用紫外、红外、质谱和NMR进行结构鉴定。根据抑瘤活性大小分步提取，最后经硅胶柱层析后，分离出6个组分，其中组分3抑瘤活性最强，腹腔注射（i．P．）50mg／kg／d，对S180荷瘤鼠的瘤重抑制率达78．30％。组分3在石油醚（60℃-90℃）中反复结晶得淡黄色结晶体，经波谱解析，确定为麦角甾醇。巴西蘑菇菌丝体醇提物中的主要抗肿瘤活性成分是麦角甾醇。     

防中远红外伪装涂料的作用机理及发展趋势

详细论述了防中远红外伪装涂料的研究现状、发展趋势、作用机理和影响因素。     

THE COMPOSITION AND VITAMIN A VALUE OF THE CAROTENOIDS OF PUMPKINS OF DIFFERENT COLORS

The carotenoid pigments of the yellow and orange flesh varieties of the pumpkins Cucurbita moschata and C.maxima were identified and quantified, α-Carotene, β-carotene, ζ-carotene, β-carotene 5,6-epoxide, β-cryptoxanthin, lutein, taraxanthin, zeaxanthin, luteoxanthin and auroxanthin were detected in the pumpkins. The difference was that the yellow variety of C. moschata had no zeaxanthin. The quantitative patterns of the two varieties were similar. Although some quantitative variation was observed, lutein, β-carotene and luteoxanthin predominated. The difference in the color between the two varieties resulted from these quantitative differences in carotenoid composition. The vitamin A activity of the C. moschata variety with yellow flesh was higher than that of the C. maxima, which had many oxygenated carotenoids.     

COMPOSITION OF THE LIPIDS OF CUCUMBER AND PEPPERS

SUMMARY— Cucumber and green peppers contain 103 mg and 400 mg total lipid per 100g raw vegetable tissue. The neutral lipids, phospholipids and glycolipids comprise 39, 49 and 15% of the cucumber lipids and 82, 2 and 16% of the pepper lipids respectively. The neutral lipids of both were composed mainly of glycerides. In the peppers the triglycerides accounted for 60% of the total lipids. Cucumber, had less glycerides but contained several unidentified sterols. Phosphatidylcholine was the major class in both vegetables accounting for 46 and 76% of the phospholipids of cucumber and pepper respectively. Palmitic, linoleic and linolenic acids were the principal fatty acid components. The lipids of peppers were very rich in linoleic acid (70%) whereas those of the cucumbers contained relatively more linolenic acid.     

伽伐尼电池式氧传感器敏感机制及性能提高

对伽伐尼电池式氧传感器的敏感机制进行了探讨，详细论述了影响电池敏感特性的因素并给出了提高传感器灵敏度、缩短响应时间和延长使用寿命的方法，文中有关钝化的理论与相关参考文献不同，采用了一些特殊手段来制作高性能的传感器。     

PHYTOCHEMICAL AND FATTY ACID PROFILE OF SELECTED RED RASPBERRY CULTIVARS: A COMPARATIVE STUDY

ABSTRACT

Seven red raspberry cultivars (Heritage, Canby, Willamette, Hollanda Boduru, Newburgh, Tulameen and Meeker) were evaluated for their total anthocyanin (TACY), total phenolics (TP), trolox equivalent antioxidant capacity (TEAC), fatty acids (FAs) and soluble sugars properties. The TACY, TP and TEAC content ranged from 171.5 to 475.0 µg/g fresh weight (fw), 864.4–1246.9 µg gallic acid equivalent/g fw and 19.4–32.7 µmol TE/g fw, respectively. The highest values of TACY, TP and TEAC content were obtained from the Newburgh cultivar. The FA compositions of raspberry cultivars ranged from 4.97 to 20.31% saturated FAs, 14.65–18.47% monounsaturated FAs (MUFAs) and 62.85–78.68% polyunsaturated FAs (PUFAs). Cultivars Meeker and Newburgh had the highest level of MUFAs, respectively, while the highest level of PUFAs was observed in cultivar Hollanda Boduru. The main soluble sugars of the seven raspberry genotypes were also separated, identified and quantified using high‐performance liquid chromatography with refractive index detection. According to the results, fructose, glucose and sucrose were detected as the main soluble sugars, while xylose and mannose were not detected in the raspberry fruits.

PRACTICAL APPLICATIONS

There have been no previous studies comparing the fruit quality characteristics of raspberry cultivars. Raspberries may be a good alternative crop with a high market value, especially highly profitable due to the long harvesting period, because of the ideal climatic conditions. The objective of this work was to evaluate seven red raspberry cultivars in terms of their total anthocyanin, total phenolic, antioxidant capacity, fatty acids profile and soluble sugar properties.     

几种PVC稳定剂在热氧老化方面的作用及协同效应

本文根据大量实验数据和曲线阐述了PVC稳定剂DOTG、DBTM、BHBM、EBHPT及HOBP(分子结构式见附录)在PVC热加工中的作用、机理以及它们相互间复合使用的比率与防PVC热氧、光氧老化的关系及其协同效应情况.     

PROPERTIES OF BIXIN AND NORBIXIN AND THE COMPOSITION OF ANNATTO EXTRACTS

SUMMARY— The melting point and ₁ ^1% _cm-values of a-bixin, β-bixin, and a-norbixin were determined and the stability of a-bixin examined under different conditions. The total pigment content of butter colors was determined. a-Bixin was the principal pigment; in addition, at least eight different pigments were present. The content of a- and β-bixin in butter colors was also determined. Because of complex formation of bixin and norbixin with a yellow pigment, the simple chromatographic method became rather laborious. This complex formation did not occur in the annatto suspensions in oil and fat. These preparations were more concentrated, while the amount of decomposition products of a-bixin was relatively slight. The stability of the pigments in butter colors appeared to be great. Investigation of annatto cheese colors showed that these extracts contain at least seven color components. The total amount of red pigment and the principal pigment a-norbixin were determined.     

壳聚糖的调血脂活性及安全性研究现状

研究表明壳聚糖具有多种生理活性，特别对其调血脂活性做了大量的动物实验和临床研究。综述了其调血脂活性以及安全性的研究现状。     

A LARGE MANNAN MOLECULE RELEASED FROM ISOLATED YEAST CELL WALLS BY THE ACTION OF SNAIL GUT JUICE

The molecular weight of the mannans dissolved from isolated yeast cell walls by the action of snail gut juice is shown to be about two to three times as large as that of the more familiar type of mannan preparation which has been extracted in the presence of sodium hydroxide. Other types of large mannan molecules are associated with certain intracellular membranes. The availability of the former materials may facilitate the study of the chemistry of the alkali-labile bonds on which the integrity of the yeast cell wall depends.     

DIETARY MANIPULATION OF THE COMPOSITION AND QUALITY OF MILK AND MILK PRODUCTS

The role of milk and milk products in the human diet is examined briefly and the possibility discussed of expanding the market for dairy products through the production by natural methods of materials with distinctive characteristics. The scope for modifying milk composition by genetic or physiological means is considered and several well documented examples are given of the manipulation of milk composition by dietary means.     

COMBINATION WITH PLANT EXTRACTS IMPROVES THE INHIBITORY ACTION OF DIVERGICIN M35 AGAINST LISTERIA MONOCYTOGENES

ABSTRACT

The susceptibility of 11 strains of Listeria monocytogenes to divergicin M35, a bacteriocin produced by Carnobacterium divergens strain M35, and to aqueous extracts of garlic, onion, oregano, red chili and black pepper at 30 and 10C, was evaluated using a microdilution assay. The susceptibility of divergicin‐resistant strains to combinations of these agents was also evaluated. Three strains were resistant to divergicin M35 (>500 µg/mL) at 30C but were more susceptible at 10C. Garlic gave the most inhibitory plant extract, followed by onion, while oregano, red chili and black pepper extracts were less active at both temperatures. Garlic extract and divergicin M35 combined or with other extracts increased inhibitory activity against the divergicin‐resistant strains. The garlic/divergicin combination was the most effective at inhibiting these strains and was bactericidal at both temperatures. Log‐phase cells were the most susceptible to the garlic/divergicin combination. Stationary‐phase cells were much more resistant at both incubation temperatures. Furthermore, the effect of the garlic/divergicin combination at inhibiting divergicin‐resistant L. monocytogenes in a food system was also studied using cold‐smoked salmon as a food model. Results indicated that this combination could efficiently reduce the viability of L. monocytogenes in smoked salmon stored at 10C.

PRACTICAL APPLICATIONS

There is increasing popularity worldwide for chemical preservative‐free, ready‐to‐eat and minimally processed seafood with low salt, fat and sugar content. Bacteriocins produced from lactic acid bacteria can have a potential application to prolong the shelf life of cold‐smoked salmon. Also, plant and spice extracts have been shown to contain antibacterial substances with potential for application in foods. Thus, this research explores the combination of divergicin M35, a bacteriocin produced by Carnobacterium divergens strain M35, and aqueous extracts of garlic, onion, oregano, red chili and black pepper to inhibit Listeria monocytogenes and to prolong the shelf life of cold‐smoked salmon.     

血栓形成机理及溶血栓药物的研究进展

血栓栓塞性疾病是目前严重危害中老年人健康的疾病，近年来随着生活节奏的加快患者数量明显增加，年龄也逐渐趋向中年，给患者及其家人乃至社会都带来了沉重的负担，因而人们越来越关注血栓的预防及其治疗。本文简介了血栓形成及影响血栓形成的主要因素，概述了溶栓药物的研究进展及其发展方向。     

食品包装安全应急准备响应机制的建立和实施

简述了当前食品包装的安全现状,初步分析食品包装的安全性问题产生的原因和对人类健康的危害,依据IS022000:2005(食品安全管理体系)对食品包装安全的应急准备响应机制进行阐述.提出针对食品链上相关组织的针对食品包装安全的应急准备与响应的系统模式,并在此基础上提出实施流程和要则.