菊芋在脱脂乳中对双歧杆菌生长的影响研究

以菊芋粉为材料,以长双歧杆菌(Blm)和两歧双歧杆菌(Bbm)为实验菌株,研究菊芋在脱脂乳中对双歧杆菌生长的影响,以期为进一步开发菊芋资源和研制双歧杆菌酸奶提供理论依据。结果表明在脱脂乳中加入3%的菊芋粉,凝乳时间有所缩短,在接种Blm的脱脂乳中缩短了0．9h,在接种Bbm的脱脂乳中缩短了1．1h。在脱脂乳中添加3%的菊芋粉后,明显促进了菌体产酸。     

一株具降胆固醇功能乳酸菌的机制研究

目的对动物双歧杆菌SQ-0001的体外环境耐受性及其降胆固醇作用进行研究。方法用邻苯二甲醛法对pH 3.0和0.3%牛胆酸钠有一定耐受性的动物双歧杆菌SQ-0001的体外降胆固醇机制进行了研究。结果动物双歧杆菌SQ-0001对pH 3.0及0.3%胆盐环境具有一定的耐受性;该菌在胆盐浓度为0.2%,培养时间为24 h时,胆固醇脱除率最高,达到91.59%;该菌降胆固醇的作用主要以吸收为主,吸收率达到63.87%,其次是降解率,为23.81%。结论动物双歧杆菌SQ-0001的环境耐受能力良好,具有很好体外降胆固醇作用,该菌株可以作为日后降胆固醇的潜在益生菌。     

双歧杆菌中胆盐水解酶的研究进展

胆盐水解酶的特性及生理功能已成为研究热点。我们探讨了国内外关于双歧杆菌中胆盐水解酶的生化特性、降胆固醇机理及其生理作用几个方面的研究进展,以期对研究双歧杆菌胆盐水解酶,以及双歧杆菌及其制品的开发利用有一定的指导意义。     

婴幼儿粪便中双歧杆菌的分离及其菌株特性研究

为筛选具有潜在益生功能的双歧杆菌,本研究采用改良MRS培养基,从婴幼儿粪便中分离到5株菌株:AR499,AR667,AR668,AR669和AR610。通过16S r DNA测序分别鉴定为两歧双歧杆菌,短双歧杆菌,动物双歧杆菌,长双歧杆菌和假小链双歧杆菌。对其耐酸耐胆盐能力和黏附性能进行测试,结果表明,菌株AR499耐酸性较好,菌株AR610有较强的耐胆盐能力,菌株AR499的自动聚集能力和细胞表面疏水性都较高。实验表明,菌株AR499可作为一株耐受性和黏附性能较好的益生菌进一步深入研究,以期应用于优良双歧杆菌产品的开发。     

从人胃肠道源乳杆菌株中初步筛选耐酸耐胆盐优良株

目的筛选对酸和胆盐耐受性均较强的优良乳杆菌株。方法模拟人体胃酸环境（pH=3）和十二指肠高胆盐环境（胆盐含量=3‰）测定104株人胃肠道源乳杆菌在酸性及高胆盐环境下作用4h后的存活菌数,并与对照相比较。对结果进行统计学分析。结果16株菌在酸性环境及高胆盐环境下4h后的活菌下降对数值均小于2。筛选出3株具有较强耐酸耐胆盐能力的乳杆菌株。结论大多数人胃肠道源乳杆菌对酸和胆盐的耐受能力均不强,对酸的耐受性普遍强于对胆盐的耐受性。     

人皮肤正常菌群分离株的生物学特性的研究

我们对由健康人皮肤上分离的菌株(F65、A14-1、ad_3和Bf_1、Bf_2五株菌)进行了较系统的生物学特性的研究,其生物学特征基本上符合表皮葡萄球菌、疮疱丙酸杆菌、干酪乳杆菌、青春双歧杆菌和婴儿双歧杆菌。做了抗生素、胆盐对羟基苯甲酸乙酯和对氯间苯二甲酚,以及(国际香型)氧化玫瑰等香精的敏感试验,并进行温度与时间、酸硷耐受性试验。     

3株罗伊氏乳杆菌生物学特性的分析比较

【目的】对3株罗伊氏乳杆菌的生物学特性进行分析比较,为后期生产应用提供一定的参考。【方法】对实验室保藏的3株罗伊氏乳杆菌的生长曲线、pH曲线、耐受人工胃液能力、耐受猪胆盐能力、黏附能力、抑菌能力和对抗生素的耐药性等特性进行了分析比较。【结果】3株菌生长趋势大致相同;3株菌对人工胃液均具有良好的耐受性,且可以有效地抑制大肠杆菌和金黄色葡萄球菌的生长;菌株L0和L2对高胆盐的环境耐受性较差,菌株L1则对高胆盐环境具有极强的耐受性;菌株L1和L2具有很强的黏附能力;3株菌对20种抗生素表现出不同的耐受性。【结论】菌株L1的生物学特性明显优于其他两株菌株,有利于后期的生产应用。     

长寿老人源双歧杆菌优良菌株的筛选

以人结肠腺癌细胞系HT-29细胞为试材,对来源于广西巴马百岁以上长寿老人肠道的24株双歧杆菌进行了体外黏附试验。结果发现,双歧杆菌均具有一定的黏附能力,其中TTF、Z2、TZ5和J-1菌株具有较高的黏附能力。进一步对4株初筛双歧杆菌耐胃酸、胆汁酸和合成B族维生素能力的试验发现,双歧杆菌TTF菌株不仅能合成较高的B1、B2、B6、B12等多种B族维生素,而且在pH3．0的条件下处理120min存活率达93．11％,同时在2％胆盐浓度下处理24h有较好的存活,具有显著的综合优势。     

长寿老人源双歧杆菌优良菌株的筛选*

以人结肠腺癌细胞系HT-29细胞为试材,对来源于广西巴马百岁以上长寿老人肠道的24株双歧杆菌进行了体外黏附试验。结果发现,双歧杆菌均具有一定的黏附能力,其中TTF、Z2、TZ5和J-1菌株具有较高的黏附能力。进一步对4株初筛双歧杆菌耐胃酸、胆汁酸和合成B族维生素能力的试验发现,双歧杆菌TTF菌株不仅能合成较高的B1、B2、B6、B12等多种B族维生素,而且在pH 3.0的条件下处理120m in存活率达93.11%,同时在2%胆盐浓度下处理24h有较好的存活,具有显著的综合优势。     

模拟人体胃肠道环境筛选益生乳杆菌

【目的】筛选具有益生特性的乳杆菌作为保健型酸奶的候选菌株。【方法】从健康人肠道和奶豆腐中分离筛选出耐受人工胃液的乳杆菌,对其进行体外益生特性(人工胃肠液耐受性、胆盐耐受性、抑菌活性及胆固醇降解能力)研究。【结果】从在乳杆菌分离培养基上有溶钙圈的41株菌株中筛选出5株耐酸、耐人工胃液较强的菌株,经16S rR NA基因测序鉴定,其中3株为乳杆菌,分别命名为植物乳杆菌Lp MT-3、植物乳杆菌Lp MT-5和唾液乳杆菌LsA F-7。在人工胃液中3株菌的耐受力均强于商品化的对照菌株LGG(鼠李糖乳杆菌GG);转入肠液4 h后直至26 h,Lp MT-5存活率基本稳定在45%左右,仅次于LGG。胆盐浓度为0.10%时,3株乳杆菌的耐胆盐能力均强于LGG;胆盐浓度为0.20%时,Lp MT-3和LsA F-7仍能存活。3株乳杆菌均具有抑菌活性,对粪肠球菌的抑制最明显,其次是金黄色葡萄球菌,对大肠杆菌、沙门氏菌的抑制作用较差。3株乳杆菌对胆固醇的清除效力依次为Lp MT-3LpM T-5Ls AF-7;清除率依次为Ls AF-7Lp MT-3LpM T-5。【结论】筛选出3株适应人体胃肠液环境、耐胆盐、抑菌及降胆固醇活力强的乳杆菌,可作为进一步开发新的益生菌产品和保健型酸奶的菌株。     

肌苷对缺氧心肌跨膜电位和收缩强度的影响

本工作在正常和缺氧情况下,观察肌苷对豚鼠心室乳头肌跨膜电位和收缩强度的影响。结果表明肌苷使正常心肌细胞动作电位时间(APD_(10)、APD_(50)延长。在缺氧心肌,肌苷使细胞静息电位增大,动作电位去极化幅度增高,零期最大去极化速度加快和动作电位时间延长。肌苷增加正常心肌收缩力,使缺氧心肌收缩的衰减显著缓和,亦即使收缩功能改善,且表现剂量-依从性。肌苷对心肌细胞跨膜电位的影响提示它很可能有抗心律失常作用,特别是在缺氧心脏。肌苷对离休乳头肌收缩的影响,证明其对心肌有直接的强心作用。     

EFFECT OF PHOSPHATIDYLSERINE ON ACETYLCHOLINE OUTPUT FROM THE CEREBRAL CORTEX OF THE RAT

The effect of sonicated suspensions of phosphatidylserine, phosphatidylethanolamine and phosphatidylcholine injected intravenously on acetylcholine release from the cerebral cortex was investigated in urethane anaesthetized rats. The electroeorticogram was also recorded. Phosphatidylserine caused a dose dependent, calcium dependent increase in acetylcholine output with no electrocorticografic changes. The increase, 75% peak effect after 150 mg/kg, was abolished by septal lesions and pretreatment with pimozide. Phosphatidylserine had no effect on acetylcholine release from brain slices in vitro. Phosphatidylethanolamine was approximately half as active as phosphatidylserine and phosphatidylcholine had no effect on acetylcholine output in vivo. It is concluded that phosphatidylserine exerts an indirect stimulating action on a septio-cortical cholinergic pathway.     

OBSERVATIONS ON THE EFFECT OF ADDED HYPOCHLORITE ON THE NUMBERS AND KINDS OF BACTERIA IN MILK

SUMMARY: In an investigation of the effect of added hypochlorite on the bacterial flora and bacterial numbers of milk no bactericidal action was apparent within 15 min of adding the disinfectant unless at least 500 p/m available chlorine had been added. After 24 hr storage at atmospheric temperature a reduction in numbers was found with 10 p/m available chlorine and this became more pronounced with increased concentrations. Micrococci seemed more susceptible to the bactericidal effect than streptococci, which formed, after 24 hr storage, the predominant residual flora where 250 and 500 p/m available chlorine had been added. Acid production by lactic streptococci was retarded at concentrations greater than 50 p/m available chlorine in a 5 hr incubation period at 30°, but after a 24 hr incubation the decrease in acid production was only apparent when 500 or 1,000 p/m available chlorine was present. Little effect on acid production by lactic streptococci was found when less than 50 p/m available chlorine had been added. The residual chlorine content of rinses of equipment sterilized in hypochlorite solutions was negligible.     

THE ANTIPROTEOLYTIC ACTIVITY OF SERUM : II. PHYSIOLOGICAL SIGNIFICANCE. THE INFLUENCE OF PURIFIED TRYPSIN INHIBITOR ON THE COAGULATION OF THE BLOOD

1. Serum antitrypsin and pancreatic trypsin inhibitor inhibited the coagulation of plasma in vitro. 2. This could be largely prevented by trypsin. 3. The anticoagulant action of the trypsin inhibitor was apparently due to its antiprothrombic action. It had no appreciable antithrombic action. 4. Examination of the blood of two hemophiliacs indicated that the prolonged coagulation time of their blood is not due to an excess of trypsin inhibitor. 5. Examination of the blood of heparinized dogs indicated that heparin does not appreciably contribute to the antiproteolytic activity of the serum.     

灭幼脲Ⅲ号对马尾松林昆虫群落多样性的影响研究

１９９５年７月至１９９６年６月在湘中丘陵区马尾松林内用灭幼脲Ⅲ号作的喷药试验结果表明,灭幼脲Ⅲ号不仅直接影响鳞翅目昆虫的物种组成主多样性水平,而且对膜翅目昆虫（主要是蚂蚁）和蜘蛛的物种组成及多样性水平有间接影响。在时间过程中,施药区鳞翅目和直翅目昆虫的多样性水平有一定程度的下降,但下降程度不如对照区大,膜翅目和蜘蛛的多样性水平则有较大程度的上升,因此林内昆虫群落趋于相对稳定。由于药剂对蚜虫种群无影     

海南岛尖峰岭热带山地雨林采伐迹地更新群落的初步分析

 海南岛西南部热带山地雨林采伐迹地上的更新群落大多数是以闽粤栲占优势的森林植被。本文以尖峰岭为例,对热带山地雨林不同采伐方式迹地上更新的群落进行了群落数量特征、种群年龄结构的分析。同时从林业生产的角度,评定了群落的更新质量,并提出了热带山地雨林适宜的采伐方式和群落更新的抚育管理方法。     

活体牦牛人工培植牛黄药理作用的研究

本文采用比较药理学的研究方法,将培植耗牛黄与天然牛黄在同等条件下进行了生物活性的考察,研究结果表明,培植牦牛黄与天然牛黄具有镇静、抗惊厥。解热及抗炎症作用,二者的作用强度与毒性也相似,认为培植牦牛黄的药效与天然牛黄基本相似,同样可供药用。     

THE EFFECT OF NEW DRUGS ON THE RHYTHMIC FUNCTION OF THE HEART

Epinephrine and related drugs (sympathomimetic amines) are the only compounds which effectively increase the rhythmic function of the heart.Effects of two new non-pressor sympathomimetic compounds were observed. One of these compounds, the isopropyl homologue of epinephrine, was found to be about five times more active than epinephrine.From clinical observations on the action of a new cardiac depressant drug, alpha-fagarine, it was concluded that the drug is very effective but that toxic reactions are unpredictable.The potency of alpha-fagarine and related compounds suggests the possible development of chemically related non-toxic drugs having an effective cardiac depressant action.     

THE EFFECT OF THE CONCENTRATION OF ENZYME ON THE RATE OF DIGESTION OF PROTEINS BY PEPSIN

1. In certain cases the rate of digestion of proteins by pepsin is not proportional to the total concentration of pepsin. 2. It is suggested that this is due to the fact that the enzyme in solution is in equilibrium with another substance (called peptone for convenience) and that the equilibrium is quantitatively expressed by the law of mass action, according to the following equation. See PDF for Equation It is assumed that only the uncombined pepsin affects the hydrolysis of the protein. 3. The hypothesis has been put in the form of a differential equation and found to agree quantitatively with the experimental results when the concentration of pepsin, peptone, or both is varied. 4. Pepsin inactivated with alkali enters the equilibrium to the same extent as active pepsin. 5. Under certain conditions (concentration of peptone large with respect to pepsin, and concentration of substrate relatively constant) the relative change in the amount of active pepsin is inversely proportional to the concentration of peptone and the equation simplifies to Schütz''s rule. 6. An integral equation is obtained which holds for the entire course of the digestion (except for the first few minutes) with varying enzyme concentration. This equation is identical in form with the one derived by Arrhenius for the action of ammonia on ethyl acetate. 7. It is pointed out that there are many analogies between the action of pepsin on albumin solutions and the action of toxins on an organism.