广东78种食物的不溶性膳食纤维含量分析

本文采用中性洗涤剂法测定了广东78种食物的不溶性膳食纤维含量,结果提示,不溶性膳食纤维的平均含量:干豆坚果类为7.12％,鲜果类为1.93％,根茎类为1.55％,叶菜类为1.31％,粮谷类为1.27％,茄瓜类为1.15％。其中干豆坚果类与茄瓜类、粮谷类、叶菜类、根茎类和鲜果类的含量差别极显著(P<0.01),而后五类食物的含量相互间差别不显著(P>0.05)。粮谷类的变异系数较大(CV:142％)。其中以加工较深的米面及其制品较低(0.31％—0.72％),而未深加工的玉米、薏米的含量则高(2.48％—6.08％)。     

Low surface tension calcium hydroxide solution is an effective antiseptic

The antimicrobial effects of a saturated calcium hydroxide solution, and in combination with 10% and 20% detergent, were evaluated on Streptococcus faecalis. Strepto-coccus sanguis, Streptococcus mutans, Streptococcus salivarius, Neisseria sp., diphlheroid, Staphylococcus aureus, Lactobacillus sp., Staphylococcus epidermidis, Bacillus suhtilis and Candida albicans. The saturated calcium hydroxide solution was effective against only four of the 11 microorganisms studied over a 60-min exposure time. The calcium hydroxide solutions con-taining detergent killed all 11 test organisms over a 30-min exposure time. This difference was statistically significant (P<0.01). No statistically significant difference in antimicrobial action was found between the 10% and 20% detergent calcium hydroxide solutions (F>0.01). However, the low surface tension (46.5 × 10^?3 Nm^?1) and high pH (10.8) of the calcium hydroxide solution with 20% detergent establish it as the more effective solution.     

方格星虫酶解物成分分析及其抗氧化作用

用木瓜蛋白酶对方格星虫（Sipunculus nudus）进行酶促水解,并对酶解物冻干粉的成分进行了分析,其中粗蛋白质量分数为69.02%,多肽质量分数为60.60%,肽的平均链长为3.73个氨基酸残基,肽分子的平均相对分子质量为447.6;游离氨基酸占5.27%。氨基酸分析结果显示,方格星虫酶解物含有17种氨基酸（色氨酸未测）,其中人体必需氨基酸含量较高,占总氨基酸数的30.62%。方格星虫酶解物中还含有P、Fe、Mg、Mn、Zn、Cu、Se等至少12种矿质元素,以及含有抗氧化作用的营养成分,并通过动物试验证明了方格星虫酶解物具有显著的抗氧化作用。方格星虫酶解物可用于食品添加或用作功能性食品。     

Oral mucosal desquamation caused by two toothpaste detergents in an experimental model

Sodium lauryl sulfate (SLS), the most widely used detergent in toothpastes, has been reported to cause adverse effects on oral soft tissues. This double-blind cross-over study describes the oral mucosal effects of SLS-containing toothpastes and pastes containing a zwitterionic detergent, cocoamidopropyl-betaine (CAPB) in an experimental model in 28 healthy females. Seven toothpastes, differing only in detergent concentration and/or type, were used: SLS (0.5, 1.0, 1.5%), CAPB (0.64, 1.27, 1.90%) and a placebo. Each participant applied 1 cm of assigned test toothpaste via a cap splint to the teeth and the mucosa of the upper jaw. The splints were used twice daily for 2 min during a period of 4 d, after which the participants were examined for oral desquamation. No other oral hygiene was allowed during the test periods. Ten days brushing with a detergent-free toothpaste was performed between each test period. Forty-five desquamative reactions were observed in 21 of 27 subjects (one was excluded) during the trial. Forty-two reactions were recorded during the SLS periods and the remaining three during the CAPB periods. The detergent-free toothpaste did not result in oral desquamation. SLS in toothpastes significantly increased the incidence of desquamation of the oral mucosa compared with toothpastes containing the detergent CAPB. The model used is not directly relevant to normal toothbrushing with toothpaste, but indicates that sensitive patients may contract mucosal irritation through SLS in toothpastes. Less toxic detergents, e.g. CAPB, are desirable in oral hygiene products.     

TD清洗消毒剂对口腔科器械消毒效果探讨

通过实验室和口腔科临床观察表明:TD清洗消毒剂(氯化磷酸三钠)对金黄色葡萄球菌、绿脓杆菌和枯草杆菌黑色变种的平均杀菌率为100.0％,对口腔科器械消毒无菌率为100％,对被HBsAg阳性血清污染的器械浸泡30分钟转阴率为98.1％。其消毒效果优于新洁尔灭,与戊二醛相同。在口腔科使用两年,未见金属器械有锈斑生成。     

Differential activation of hepatitis B DNA polymerase by detergent and salt

Three patterns of activity were evident when the differential activation of the DNA polymerase associated with serum Dane particles by nonionic detergent and salt was investigated. The patterns were obtained by plotting the increase in enzyme activity mediated by the detergent Nonidet P-40 (NP-40) in increasing concentrations of KCl compared to the activity observed in the absence of detergent. The pattern of differential activity of hepatitis B (HB) DNA polymerase in detergent and salt was altered by subjecting the HBAg preparations to shearing forces. Hepatitis B DNA polymerase activity was stable even in NP-40 concentrations as high as 10%. In addition to hepatitis B DNA polymerase, DNA polymerase activated by calf thymus DNA was found in pellets containing Dane particles. The latter DNA polymerase activity was also activated by NP-40 and was not decreased by DNAse; this DNA polymerase coprecipitated with hepatitis B antigen (HBAg) upon addition of anti-HBs. However, the DNA polymerase activated by calf thymus DNA was inhibited by 0.4 M KCl. Electron microscopic observations of serum Dane particles in 0.4 M KCl showed no alterations of morphology of these particles when compared to particles in low-salt buffer. The data indicated that KCl activated HB DNA polymerase by a different mechanism from that of shear or NP-40, which removed the surface antigen coat from the Dane particles.     

聚—（羟丙基、丙基）—天冬酰胺材料体外酶解及植入小鼠体内的观察

目的：观察4种不同摩尔比的聚－（羟丙基、丙基）－天冬酰胺材料在体外酶解和植入小鼠体内后的变化。方法;用木瓜蛋白酶和胰酶对材料作了体外酶解试验,用凝胶色谱法对降解物碎片作了测定;用光镜、扫描电镜、透射电镜等对材料在埋植部位、肝、肾组织内的降解碎片进行观察;对材料植入小鼠体内后的生化指标（血红蛋白、白细胞、谷丙转氨酶、肌酐作了测定。结果：聚－（羟丙基、丙基）－天冬酰胺材料在体外能被逐步酶解。在植入小鼠体内的5周内,在埋植部位、肝、肾组织内能观察到材料的碎片。结论：聚－（羟丙基、丙基）－天冬酰胺材料能在体内、外逐步降解,植入小鼠体内后对动物的血象、肝、肾功能无明显的影响,具有生物相容性。     

酶法合成L—丝氨酸及反应液中氨基酸的分离

含ｇｌｙＡ的基因工程菌所表达的ＳＨＭＴ可催化甲醛和甘氨酸特异地合成Ｌ－丝氨酸。对酶法合成的部分条件进行了优化,并根据甲醛滴定的原理,确定了通过检测ｐＨ变化控制甲醛流加速度的方案,最终的反应液中Ｌ－丝氨酸浓度达０．２ｍｏｌ／Ｌ。反应结束后的酶反应液中同时含有甘氨酸和丝氨酸,利用国产７１７树脂获得较为理想的分离效果,丝氨酸的收率达７７％,高效液相分析表明其中不含甘氨酸等杂质。     

Hemorrhagic activity of Bothrops venoms determined by two different methods and relationship with proteolytic activity on gelatin and lethality

The changes in hemorrhagic activity, proteolytic activity on gelatin and the lethal potency of four Bothrops venoms treated at different pH values or with EDTA were studied. Venoms from B. alternatus, B. jararaca, B. moojeni and B. neuwiedii of Argentina were preincubated at pH 5.8, 5.1 or 3.8 or with EDTA and the hemorrhagic activity expressed as size of the hemorrhagic lesion or as the amount of hemoglobin extracted, the proteolytic activity on gelatin and the lethal potency were determined. Although the MHDs recorded in rats were 19–56 fold higher than those recorded in mice, the A₅₅₀ extracted per gram of hemorrhagic haloes was very similar in rats or mice independent of the venom dose. Inhibition of proteolytic activity after preincubation at pH 5.1 or 3.8, agrees with the decreased amount of hemoglobin extracted from the hemorrhagic haloes, and with the increase in mean survival time after the i.p. injection to mice. Preincubation with EDTA resulted in 80% inhibition of hemorrhagic activity of B. jararaca venom and complete inhibition with the other Bothrops venoms tested. Measurement of the amount of hemoglobin extracted gives significant information in comparative studies, not available by measurement of the size of hemorrhagic haloes.     

三七叶皂苷酶水解产物的提取分离及结构鉴定

目的：对三七叶皂苷酶水解产物进行提取分离和结构鉴定。方法：在正交设计优选的酶解条件下，利用β-葡聚糖苷酶水解三七叶皂苷制备酶水解产物；大孔树脂法提取、柱层析法分离酶水解产物、光谱法确定酶水解产物的化学结构。结果：得到2种酶水解产物，经鉴定分别为人参皂苷C-K和人参皂苷-Mc。结论：利用大孔树脂提取及柱层析分离技术，可以实现三七叶皂苷酶水解产物的分离与制备。