20种药用蕨类植物提取液抑菌试验研究

以20种药用蕨类植物提取液对金黄色葡萄球菌、大肠杆菌、八叠球菌、变形杆菌、枯草杆菌、酵母菌进行抑菌活性研究,结果表明,20种蕨类提取液至少对一种供试微生物具有抑菌活性。样品蕨类醇提液比水提液具更强的抑菌活性,供试菌有阳性结果的水提液,平均抑菌圈直径10.12mm,而醇提液则为11.92mm。试验结果还表明,药用蕨类对枯草杆菌抗菌活性效果最明显,对酵母菌效果最差。不同蕨类植物其地上部分和地下部分抑菌效果不尽相同。     

具抑菌活性海洋微生物的筛选

从上海郊区海域采集的海水、海泥样中分离出193株海洋细菌,对其进行抑菌活性菌株的筛选。对分离出的菌株分别利用琼脂块法和管碟法进行初筛和复筛,结果显示有29株海洋细菌具有抑菌活性,占总分离菌株的15%,其中抑菌能力较强的G4抑菌谱较广,同时能抑制革兰氏阳性和阴性指示菌。     

云南省4种蕨类植物提取液的抑菌活性

为了合理开发利用蕨类植物资源,本研究利用圆纸片法分析了云南省4种蕨类植物单芽狗脊蕨(Woodwardia unigemmata)、蜈蚣蕨(Pteris vittata)、鸡足山耳蕨(Polystichum jizhushanense)和灰绿耳蕨(Polystic-hum eximium)的提取液对金黄色葡萄球菌(Staphylococus aureus)、大肠杆菌(Escherichia coli)和枯草芽孢杆菌(Bacillus subtilis)的抑菌活性。抑菌试验结果表明,当4种蕨类植物提取液浓度分别为10%、8%、6%和4%时,对照组无抑菌圈出现,单芽狗脊蕨提取液对大肠杆菌和金黄色葡萄球菌无抑菌活性,灰绿耳蕨提取液对金黄色葡萄球菌无抑菌活性,其它的蕨类植物提取液对供试微生物都表现出不同程度的抑菌活性;并且这4种蕨类植物提取液至少对一种供试细菌具有抑菌活性,抑菌活性范围为8～14mm,平均抑菌圈直径为11.2mm,4种提取液对枯草芽孢杆菌抗菌活性效果最明显。由此,我们推测本研究中的4种蕨类植物均有抗菌物质存在,并将有望成为筛选抗菌新型药物的种质资源。     

苦豆籽中抑菌活性物质的跟踪筛选研究

目的:对苦豆籽中抑菌活性物质进行跟踪筛选。方法:采用溶剂萃取法获得苦豆籽不同极性溶剂萃取的浸膏,对其浸膏及实验室自制单体类化合物通过纸片扩散法(K-B)法进行抑菌试验研究。结果:苦豆籽粗提物对实验所用菌种都有不同程度的抑制作用,尤其是氯仿浸膏中可能含大量生物碱,因此表现出强的抑菌效果;苦豆籽单体类化合物对实验所用菌种都具有较强的抑制作用,苦参碱的抑菌效果最好。结论:苦豆籽中主要抑菌成分为生物碱类化合物,其中苦参碱的抑菌效果优于氧化苦参碱。     

元江仙人掌植物内生真菌的抑菌活性筛选研究

从云南元江野生仙人掌的肉质茎中分离出28株内生真菌,经形态学分类鉴定归于3个目,3个科,10个属。同时选择30种病原微生物作为指示菌进行抑菌试验,研究其抑菌活性。结果表明,3株元江仙人掌内生真菌分别对细菌、植物病原真菌和皮肤致病真菌多种病原微生物有较为明显的抑制生长作用。     

山鸡椒植物源抑菌成分的筛选研究

以山鸡椒为植物材料,以活性追踪的方法测定了不同组分对几种植物病原菌的抑制活性,并从中分离纯化出一种有效抗菌物质L1。实验结果表明:粗提物不同萃取相中,乙酸乙酯相的抑制作用最好,其对杨树溃疡病菌和苹果霉心病菌抑制率达到75%以上;乙酸乙酯相各个组分对几种植物病原真菌均有一定的抑制活性,其中组分6和组分7抑菌效果强,组分6对苹果霉心病菌抑制率达到100%,组分7对番茄灰霉病菌抑制率达到100%;而对抑菌活性物质L1的抑菌活性研究中,随着L1浓度逐渐升高,对几种病原菌的抑制作用也依次增强,尤其是对苹果霉心病菌的抑制效果更加明显,在供试浓度为0.1 mg/mL时,抑制率达到100%;活性成分L1最终通过波谱学方法和文献对比确定为5,8-二羟基-67,-二甲氧基黄酮。     

福建福州鼓山药用蕨类植物资源调查

经调查,福州鼓山药用蕨类植物共有42种,分属21科,31属。本文对其药用价值及其生境特征进行描述。     

福建福州鼓山药用蕨类植物资源调查

经调查,福州鼓山药用蕨类植物共有４２种,分属２１科,３１属。本文对其药用价值及其生境特征进行描述。     

豆豉中高效抑菌活性乳酸菌的筛选及其抑菌研究

目的从云南传统发酵豆豉中分离乳酸菌,并从中筛选具有高抑菌活性的菌株,进一步研究其抑菌谱,并初步分析其抑菌机制,为新型生物防腐剂的开发提供理论依据。方法应用传统纯培养技术及spot-on-lawn法从云南传统发酵豆豉中筛选得到具有抑菌作用的乳酸菌40株,并从中筛选得到1株具有高效抑菌活性的植物乳杆菌YM-4-3菌株。通过HPLC和紫外分光对其主要抑菌物质进行分析与抑菌试验。结果 YM-4-3菌株是1株具有新型生物防腐剂应用潜力的乳酸菌菌株。结论初步推测YM-4-3菌株抑菌机制为有机酸主导,细菌素和其他化学抑菌物质协同作用。     

胶州湾沉积物可培养细菌的多样性及其抑菌活性

【目的】海洋微生物在活性物质开发方面具有巨大的应用前景。为了研究胶州湾微生物的多样性和抑菌活性,选取胶州湾9个观测站点的沉积物进行了细菌多样性及抑菌活性分析。【方法】采用YPD和Z2216E培养基分离细菌,通过16S r RNA基因测序对分离菌株进行分类鉴定,继而采用牛津杯法考察分离菌株对7株指示菌的抑菌活性,最后用PCR方法筛选16株代表菌的PKSI、NRPS、CYP、Phz E和d TGD基因。【结果】从胶州湾沉积物中共分离出76株细菌,通过对16S r RNA序列分析,将其归为8个科11个属:节杆菌属、考克氏菌属、微球菌属、微杆菌属、假交替单胞菌属、Oceanisphaera、海单胞菌属、葡萄球菌属、芽孢杆菌属、硫胺素芽孢杆菌属和短芽孢杆菌属,其中分离细菌中有34株至少对1种指示菌有抑菌活性。所选取的16株菌均能检测到一种功能基因,且其中5株菌能同时检测到3种以上的功能基因。【结论】以上研究表明胶州湾海域有丰富的微生物资源,在生物活性次级代谢产物合成上有较大潜力。     

山东半岛农药污染点源放线菌多样性及抑菌活性

【目的】探究山东半岛农药污染点源放线菌多样性及非链霉菌抑菌活性,试图发现新放线菌和新抗生素。【方法】通过16S rDNA序列对已分离得到的154株纯培养放线菌进行初步分类鉴定并进行系统发育分析;采用管碟法和菌丝生长速率法检测10株非链霉菌的抑菌活性。【结果】154株放线菌覆盖7个科,8个属,有一株非链霉菌(205)可能为潜在的新种。10株非链霉菌的发酵液均对供试的植物病原真菌和细菌有不同程度的抑制作用,尤其是菌株Microbacterium oxydans JN853773和Kocuria rosea JN192402对所有供试病原菌都有强烈的抑制作用。【结论】农药污染点源可以作为开发新型抗生素产生菌的重要来源。     

中国蕨类植物孢子形态的研究V. 铁角蕨科

利用扫描电镜对国产铁角蕨科Aspleniaceae 8属59种植物的孢子形态进行了观察。铁角蕨科植物孢子为单裂缝,两侧对称,极面观为椭圆形、宽椭圆形或近圆形;赤道面观为肾形、半圆形、宽椭圆形、椭圆形或近圆形。极轴长17-41 μm,赤道轴长23-60 μm。外壁光滑。周壁较厚,由周壁形成孢子的表面纹饰。主要纹饰类型有6种: (1)窗孔状纹饰。铁角蕨属Asplenium的厚叶铁角蕨A. griffithianum、北京铁角蕨A. pekinense、肾羽铁角蕨A. humistratum属于此种类型。(2)脊状纹饰。铁角蕨属的假大羽铁角蕨A. pseudolaserpitiifolium、毛轴铁角蕨A. crinicaule等7种属于此种类型。(3)翅状纹饰。铁角蕨属有14种属于此种类型,如江南铁角蕨A. loxogrammioides、齿果铁角蕨A. cheilesorum等;细辛蕨Boniniella cardiophylla、过山蕨Camptosorus sibiricus、水鳖蕨Sinephropteris delavayi、对开蕨Phyllitis scolopendrium、疏脉苍山蕨Ceterachopsis paucivenosa和药蕨Ceterach officinarum也属于此种类型。(4)翅脊状纹饰。有铁角蕨属的21种和巢蕨属Neottopteris的6种属于此种类型。(5)角状纹饰。阔足巢蕨N. latibasis属此类型。(6)丝毛状纹饰。只有阔基苍山蕨Ceterachopsis latibasis属此类型。从孢粉学的角度对该科的分类和系统演化进行了探讨。     

海南岛吊罗山蕨类植物的多样性及其保育

对海南岛吊罗山的蕨类植物进行了专题研究。吊罗山有蕨类植物 4 3科 10 0属 2 13种及 4变种 ,其中 5种为海南新记录。蕨类物种密度高达 5 5 .8种 / 10 0km2 ,为海南蕨类多样性中心之一。该地蕨类植物区系以水龙骨科和膜蕨科为优势科 ,表现出明显的热带性质 ,热带分布的科、属、种分别达到 10 0 %、93.2 %和 95 .3%。在垂直分布上 ,蕨类植物的生态特点与植被类型相关 ,随着海拔升高 ,阳生性蕨类减少 ,阴生性蕨类、附生与石生蕨类增多 ,蕨类物种多样性在海拔 6 0 0～ 10 0 0m地段最为丰富。按照 2 0 0 1年IUCN红色名录等级及标准评估 ,在海南岛范围内 ,吊罗山有 36种受威胁蕨类植物 ,其中 6种为极危物种 ,13种为濒危物种 ,17种为渐危物种 ,这 36种受威胁蕨类中有 8种属于国家II级保护植物。导致这 36种蕨类植物受威胁的原因主要有 :人为直接破坏、生境旱化和分布区限制     

Hydrophobicity and antimicrobial activities of quaternary pyridinium salts

Aims: To explore the relationship between chemical structures and antimicrobial activities of quaternary ammonium salts (QASs), particularly the impact of hydrophobicity of the salts on the antimicrobial functions. Methods and Results: Four QASs, i.e. 4‐aminododecylpyridinium chloride, 4‐acetylaminododecylpyridinium chloride, 4‐benzoylaminododecylpyridinium bromide and 4‐(1‐naphthoyl) aminododecylpyridinium bromide were employed in antimicrobial tests against both Gram‐negative and Gram‐positive bacteria, Escherichia coli and Staphylococcus aureus. These four QASs possess the same long alkyl chain but different hydrophobic substituents at the 4‐amino group. Antimicrobial activity of QASs was measured in liquid phases by growing bacterial cultures in the presence and absence of the QAS. The most hydrophobic compound exhibited the strongest antimicrobial activity than other salts. Conclusions: All of the quaternary pyridinium salts exhibited significant antimicrobial activities but in different extents according to their hydrophobicity at the 4‐amino position. QASs having larger hydrophobic groups were significantly more effective than that with smaller groups. Significance and Impact of the Study: This research revealed that hydrophobic and aromatic ring structures at 4‐amino position on quaternary aminopyridinium ring could improve antimicrobial activity of the salts. The results could assist understanding and development of antimicrobial QASs.     

Characterization,antimicrobial, antioxidant,and anticoagulant activities of silver nanoparticles synthesized from Petiveria alliacea L. leaf extract

Abstract

Phytosynthesis of silver nanoparticles (AgNPs) using leaf extract of Petiveria alliacea (PA) was the focus of this research work. The PA-AgNPs were characterized by UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) study. Studies were made on the AgNPs for antibacterial, antifungal, anticoagulant, free-radical scavenging, and hydrogen peroxide scavenging activities. The crystalline PA-AgNPs were monodispersed, with a size range of 16.70–33.74?nm and maximum absorption at 410?nm. FTIR analysis displayed prominent peaks at 3430.6, 1711.8, and 1165.9/cm, which showed the existence of phenolic compounds and proteins in the synthesis of AgNPs. PA-AgNPs was active against Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus, with 100% inhibition. The PA-AgNPs also displayed good antifungal properties, as the concentrations of 100 and 150?µg/mL had 100% inhibition toward Aspergillus fumigatus and Aspergillus flavus. However, there was 66.67% inhibition of Aspergillus niger. It scavenged both DPPH and H₂O₂ by 70.69 and 89.02%, respectively. PA-AgNPs also prevented the coagulation of human blood. This study, being the first of its kind to use the leaf extract of PA for the synthesis of AgNPs has shown that PA-AgNPs can find biomedical applications.     

Cytotoxic,antioxidant, and antimicrobial activities of Celery (Apium graveolens L.)

Celery (Apium graveolens Linn, Family: Apiaceae) is a common edible herb used as a spice in the traditional medicine of several nations since time immemorial. The whole plant is extensively used in cooking as soups and salads. A. graveolens has various pharmacological properties such as anticancer, anti-obesity, anti-hepatotoxic, and antihypertensive agents. Hence, it is of interest to document the in vitro cytotoxic, antioxidant, and antimicrobial activity of A. graveolens. The plants were collected in the local market, shade dried, and different parts of the plants were extracted with 70% ethanol using a cold maceration process. Antioxidant tests were performed based on the various radical scavenging methods. Antimicrobial activity and MIC were completed using the respective cup-plate and two-fold serial dilution method. In vitro cytotoxic studies were achieved by the MTT; Sulphorhodamine B assayed total cell protein content. DLA and ESC cells determined the short-term toxicity. The leaf extract exhibited significant antioxidant properties against NO, DPPH, ABTS, LPO, and HPO methods. Thus, potential inhibition against Gram-positive, Gram-negative, and fungal strains within the MIC ranges of 250-500 µg/ml was observed. All the extracts of the plant presented in the study revealed greater cytotoxicity effects against five respective cancer cell lines, L6, Vero, BRL 3A, A-549, L929, and L-929 with the ranging of 443-168.5 µg/ml. Thus, we show that A. graveolens possess a potential cytotoxic, antioxidant, and antimicrobial activity.