Antimicrobial activity of the essential oil of Centaurea aladagensis

Composition of the water-distilled oil of the aerial parts of Centaurea aladagensis, endemic in Turkey, was analysed by GC-MS. Hexadecanoic acid (39.3%), caryophyllene oxide (6.6%) and hexahydrofarnesyl acetone (4.3%) were found as main constituents in the oil. The oil was tested against 7 human pathogenic microorganisms.     

Antimicrobial activity of alkaloidal fraction from barks of Himatanthus lancifolius

The alkaloidal fraction from Himatanthus lancifolius barks demonstrated a broad-spectrum in vitro antimicrobial activity for most of the Gram (+) and Gram (-) tested microorganisms.     

Antimicrobial activity of Hedychium spicatum

Extracts from rhizomes of Hedychium spicatum were tested for their antibacterial and antifungal activity. Essential oil, petroleum ether and chloroform extracts showed inhibitory activity against Gram (+) and Gram (-) bacterial cultures, including a strain of methicillin and vancomycin resistant Staphylococcus aureus and fungal cultures.     

Compositions and antimicrobial activities of the essential oils of two Hypericum species from Turkey

The chemical compositions of essential oils obtained from Hypericum hyssopifolium var. microcalycinum and Hypericum lysimachioides var. lysimachioides were analysed by using GC and GC-MS. Caryophyllene oxide was found to be the major component. The essential oils of both Hypericum species showed antimicrobial activity against nine microorganism at a concentration of 60 to 80 microg/ml.     

Linalool production from the leaves of Bursera aloexylon and its antimicrobial activity

The oil of the leaves of Bursera aloexylon was found to contain a high linalool level (96.7 %). The antimicrobial activity tests indicated that the oil was effective against Rhodococcus equi (0.60 mg/ml) and Staphylococcus epidermides (0.15 mg/ml).     

Antimicrobial activity of crude methanolic extract of Satureja khuzistanica

The methanolic extract of the aerial parts of Satureja khuzistanica was investigated for its antimicrobial activity. The maximum antibacterial and antifungal activities were observed against Staphylococcus aureus and Candida albicans.     

日粮添加抗菌肽制剂对荷斯坦牛乳中体细胞数的影响

选用体况、胎次、泌乳期以及产奶量相近的荷斯坦泌乳奶牛48头,随机等分成对照组和试验组,在试验组日粮添加抗菌肽制剂50g／（头·d）以研究其对牛奶体细胞数的影响。试验结果表明,与对照组相比,日粮添加抗茵肽制剂能极显著地降低牛乳体细胞数75．86％（P〈0．01）,同时提高乳脂率（P〈0．05）,但对乳蛋白率没有影响（P〉0．05）。     

光滑爪蟾抗菌肽的分离纯化和对癌细胞的生长抑制作用

通过凝胶过滤层析及高效液相色谱法,从皮肤分泌物中分离出具有抑菌活性的物质,即光滑爪蟾抗菌肽。以大肠癌细胞为体外实验模型,通过细胞形态学、MTS试验,研究光滑爪蟾抗菌肽对SW480细胞的杀伤和生长抑制作用。结果表明,经过分离纯化,得到较纯的活性物质,即光滑爪蟾抗菌肽。通过细胞形态学观察,光滑爪蟾抗菌肽作用组中,细胞的数量明显减少,细胞明显皱缩,成圆形,细胞间隙增大,死细胞增多。MTS试验表明,光滑爪蟾抗菌肽对SW480的生长抑制作用随着浓度的增加而加强。     

枯草芽孢杆菌SO113分泌蛋白的抑菌作用及抗菌蛋白的分离纯化

枯草芽孢杆菌（Bacillus subtilis)SO113对水稻白叶枯病菌（Xanthomonas oryzaepv.oryzae）有强烈的抑菌作用（表现出一透明抑菌圈）。培养液上清中加入60％饱和度的硫酸铵沉淀所得的蛋白粗提液对热稳定，对链霉蛋白酶E不敏感，对蛋白酶K部分敏感，对中国各稻区白叶枯病菌的7种致病型都有强烈的抑杀作用，蛋白粗提液100℃加热15min后脱盐，经DEAE0－Sepharose Fast Flow柱层析得3个未分开的抗菌活性峰，示吸附部分经CM－Sepharose Fast Flow柱层析，得到1个主活性峰，由于B.subtilis SO113的分泌蛋白对水稻白叶枯病菌表现出良好的广谱抗性以及丰富的抗菌活性峰，因此对其进一步的研究和设法隆编码抗菌蛋白的基因都具有重要意义。     

不同结构对囊素样肽的免疫活性影响

化学合成单拷贝（BS）、30拷贝串联（KG30）和30拷贝分支结构（MAP）3种不同结构的囊素样肽，通过体外外周血淋巴细胞刺激增殖试验、杂交瘤细胞抗体分泌刺激试验、E-玫瑰花环试验和体内小鼠腹腔巨噬细胞吞噬功能、新城疫疫苗免疫应答的测定，比较了其免疫增强活性。结果表明，BS和MAP的活性显著高于KG30，BS体外试验活性优于MAP，而MAP体内试验活性优于KS。结构对囊素的活性有显著影响，以分支结构的囊素增强免疫效果最好。