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1.
Phytochemical analysis of the root bark of Bauhinia variegata Linn yielded a new flavanone, (2S)-5,7-dimethoxy-3',4'-methylenedioxyflavanone (1) and a new dihydrodibenzoxepin, 5,6-dihydro-1,7-dihydroxy-3,4-dimethoxy-2-methyldibenz [b,f]oxepin (2) together with three known flavonoids (3-5). The structures of the new compounds were determined on the basis of spectral studies.  相似文献   

2.
A new galactose-specific lectin was purified from seeds of a Caesalpinoideae plant, Bauhinia variegata, by affinity chromatography on lactose-agarose. Protein extracts haemagglutinated rabbit and human erythrocytes (native and treated with proteolytic enzymes), showing preference for rabbit blood treated with papain and trypsin. Among various carbohydrates tested, the lectin was best inhibited by D-galactose and its derivatives, especially lactose. SDS-PAGE showed that the lectin, named BVL, has a pattern similar to other lectins isolated from the same genus, Bauhinia purpurea agglutinin (BPA). The molecular mass of BVL subunit is 32 871 Da, determined by MALDI-TOF spectrometry. DNA extracted from B. variegata young leaves and primers designed according to the B. purpurea lectin were used to generate specific fragments which were cloned and sequenced, revealing two distinct isoforms. The bvl gene sequence comprised an open reading frame of 876 base pairs which encodes a protein of 291 amino acids. The protein carried a putative signal peptide. The mature protein was predicted to have 263 amino acid residues and 28 963 Da in size.  相似文献   

3.
赵能  原晓龙  陈剑  陈中华  王娟  杨宇明  王毅 《广西植物》2017,37(8):1068-1073
牛樟芝作为一种珍稀食用和药用菌,具有极大的开发潜力。该研究以麦芽浸粉肉汤液体培养基(BD,美国BD公司)对牛樟芝菌丝体进行摇床培养60 d后,收获发酵液并用乙酸乙酯对其进行萃取,浓缩至干获得提取物;同时,采用抑菌圈法评价培养物对13种致病细菌抗菌活性(蜡样芽孢杆菌、缓慢芽孢杆菌、无乳链球菌、短小芽孢杆菌、福氏志贺氏菌、枯草芽孢杆菌、金黄色葡萄球菌、藤黄微球菌、副溶血性弧菌、溶血性葡萄球菌、铜尿假单胞菌、乙型副伤寒沙门氏菌、大肠埃希菌),并检测相应致病细菌的最低抑制浓度(MIC)。结果表明:牛樟芝麦芽浸粉肉汤发酵液提取物对供试的13种致病菌均有抑菌活性;在供试的13种致病菌中,提取物对缓慢芽孢杆菌、短小芽孢杆菌、枯草芽孢杆菌、副溶血性弧菌、藤黄微球菌5种致病菌的最低抑制浓度值均小于80μg·m L~(-1),其中对藤黄微球菌的最低抑制浓度最低为66.5μg·m~(-1);随着培养时间的增加,提取物的抗菌活性也增加。这说明牛樟芝菌丝体在液体培养条件下,能够产生广谱高效抑菌活性的次生代谢产物。该研究结果为牛樟芝进一步的有效利用开发奠定了理论基础。  相似文献   

4.
A new lectin (BvcL) from seeds of a primitive Brazilian Caesalpinoideae, the Bauhinia variegata candida was purified and biochemical characterized. BvcL was isolated by gel filtration chromatography on Sephadex G75 and affinity chromatography on immobilized d-lactose column. SDS-PAGE showed that BvcL under non-reducing condition presents two bands of 68 and 32 kDa and a single band of 32 kDa in reducing condition. However, only one band was seen in native PAGE. The hemagglutination activity of BvcL was not specific for any human blood group trypsin-treated erythrocytes. Carbohydrate inhibition analysis indicated that BvcL is inhibited by lactose, galactose, galactosamine and other galactoside derivates. Amino acid analysis revealed a large content of Ser, Gly, Thr, Asp and Glu and low concentrations of Met, Cys and His. Intrinsic fluorescence of BvcL was not significantly affected by sugar binding galactose; and aromatic-region CD is unusually high for plant lectins. The N-terminal amino acid sequence of 17 residues showed 90% sequential homology to galactose-specific legume lectins of the subfamily Caesalpinoideae.  相似文献   

5.
AIMS: The objective of this study was to determine the antifungal activity of flurbiprofen against dermatophytes like Trichophyton, Microsporum and Epidermophyton species. METHODS AND RESULTS: Susceptibility tests were performed against dermatophytes like Trichophyton, Microsporum and Epidermophyton species by the microbroth dilution method. Among the dermatophytes tested, Trichophyton, Microsporum and Epidermophyton species are remarkably susceptible to this compound (MIC(50): 8-16 microg ml(-1)). A yeast pathogen, Candida albicans, and a bacterium, Staphylococcus aureus, are also susceptible to flurbiprofen. CONCLUSIONS: Flurbiprofen is a non-steroidal anti-inflammatory compound with strong antifungal activity, which is not found in two well known and medically used antifungal organic acids like benzoic and salicylic acids. SIGNIFICANCE AND IMPACT OF THE STUDY: The present action of flurbiprofen on microbes indicates its future prospects as an antimicrobial agent against dermatophytes and yeast pathogens. However, in view of the anti-inflammatory property of flurbiprofen, its antifungal action may provide an additional advantage for use as a skin ointment.  相似文献   

6.
A novel series of 2-(5-methyl-1,3-diphenyl-1H-pyrazol-4-yl)-5-phenyl-1,3,4-oxadiazoles 7(am) were synthesized either by cyclization of N′-benzoyl-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide 4a using POCl3 at 120 °C or by oxidative cyclization of hydrazones derived from various arylaldehyde and (E)-N′-benzylidene-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide 5(ad) using chloramine-T as oxidant. Newly synthesized compounds were characterized by analytical and spectral (IR, 1H NMR, 13C NMR and LC–MS) methods. The synthesized compounds were evaluated for their antimicrobial activity and were compared with standard drugs. The compounds demonstrated potent to weak antimicrobial activity. Among the synthesized compounds, compound 7m emerged as an effective antimicrobial agent, while compounds 7d, 7f, 7i and 7l showed good to moderate activity. The minimum inhibitory concentration of the compounds was in the range of 20–50 μg mL−1 against bacteria and 25–55 μg mL−1 against fungi. The title compounds represent a novel class of potent antimicrobial agents.  相似文献   

7.
The antimicrobial activities of five commercial disinfectants containing quaternary ammonium compound-isopropanol (D1), sodium methyl dithiocarbamate (D2), sodium thiocarbamate (D3), sodium dimethyl dithiocarbamate (D4) and formaldehyde (D5) were studied against three main saccharolytic indigenous isolates (Bacillus cereus, Lactobacillus plantarum and Leuconostoc mesenteroides) from a beet sugar extraction line. Preliminary studies suggested that although all the disinfectants were effective against those isolates, the high economic cost in combination with large amounts of the disinfectants D2, D3 and D4 weaken their possibility for industrial use. Therefore, the minimum inhibitory concentration (MIC) of the other two examined disinfectants D1 and D5 was determined and survivor curves were obtained, for a period of 7 days. Bacterial counts against time (h) suggested that D1 was more effective than D5 against the microbial population. In particular, D1 was bacteriolytic above 7 mg/l for B. cereus and bactericidal above 80 mg/l for Lc. mesenteroides and above 100 mg/l for L. plantarum. The disinfectant D5 was bacteriolytic above 25 mg/l for B. cereus and bactericidal above 500 mg/l for Lc. mesenteroides and L. plantarum. Taking into consideration both features, i.e. high concentration and very low cost, the use of D5 (formaldehyde) appeared more suitable to the concerned beet sugar processor. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

8.
胡欢  左国营  张泽萍 《广西植物》2018,38(4):428-440
该文研究36种常用中药材80%乙醇提取物在体外抗临床常见致病菌的抗菌活性。采用药敏纸片法测耐药菌的耐药谱,中药粗粉用80%乙醇浸泡提取,提取液减压浓缩得浸膏,通过琼脂打孔法测定提取物抑菌圈,再通过微量倍比稀释法测定最低抑菌浓度(MIC)和最低杀菌浓度(MBC)。结果表明:36种中药材醇提物中,有15种具有广谱抗菌活性,对实验中各标准菌表现出不同程度的抑制作用,对MRSA抗菌活性也较强。其中,岩陀、卷柏、首乌藤、苏木、乌药、夏枯草6种药材的抗菌活性比较突出,抑菌圈均大于11 mm,细菌对其表现为中高度敏感;它们对7株标准菌的MIC/MBC值除个别为12.5 mg·m L~(-1)以外,均小于1.563 mg·m L~(-1),对16株MRSA的MIC/MBC值均小于1.563 mg·m L~(-1),它们的萃取层活性均小于1 mg·m L~(-1)。所筛选出的15种抗菌活性较强的中药材,可为后续研究其活性单体化合物和作用机制,研发有效的抗多重耐药菌的中药制剂以及解决细菌耐药性问题提供一定的参考。  相似文献   

9.
In vitro propagation protocols were established for two leguminous trees, Bauhinia variegata and Parkinsonia aculeata. In each case axillary shoot proliferation was achieved from nodal explants from mature (6-2-8 years) trees using Murashige & Skoog's medium supplemented with 2.22–31.1 M of 6-benzyladenine. Subsequent rooting of the regenerated shoots was achieved on medium containing 2.46–14.8 M of indole-3-butyric acid. Successful transfer of the regenerants to soil has been accomplished.  相似文献   

10.
A total of nine groups of ruffed lemurs (Varecia variegata variegata), as well as one solitary individual, were observed on Nosy Mangabe, an island located off the eastern coast of Madagascar, for a total 536 min between November 30 and December 8, 1983. The average group size was 2.8 animals (N=5), and the population density was 175 animals/km2, as estimated from direct observation and location of vocalization. During the same period, nine groups of brown lemurs (Lemur fulvus albifrons) and one solitary individual were observed for a total 320 min. One group of brown lemurs was composed of eight animals (two adult males and females, one male juvenile, two infants, and one individual of undetermined age and sex). Feeding competition occurred between the two species, with whichVarecia variegata variegata dominating.  相似文献   

11.
Adrenomedullin, a novel vasoactive peptide, is known to be expressed by many surface epithelial cells and it was postulated that this peptide may have a protective role. The objective of the study was to assess the antimicrobial activity of adrenomedullin against members of the human skin, oral, respiratory tract and gut microflora using disc diffusion and broth microdilution assays. All strains of bacteria screened in an agar diffusion assay were sensitive; gram-positive and gram-negative bacteria were equally susceptible. No activity against the yeast Candida albicans was observed. In a broth microdilution assay, minimum inhibitory and minimum bacteriocidal concentrations ranged from 7.75 x 10(-1) to 12.5 microg ml(-1) and 0.003 to > 25.0 microg ml(-1), respectively. We propose an antimicrobial role for adrenomedullin. participating in the prevention of local infection, thus contributing to host defence systems.  相似文献   

12.
Robust evaluation and comparison of antimicrobial technologies are critical to improving biofilm prevention and treatment. Herein, a multi-pronged experimental framework and statistical models were applied to determine the effects of quaternary pyridinium salt, 4-acetyl-1-hexadecylpyridin-1-ium iodide (QPS-1), on Streptococcus mutans in the planktonic, biofilm-forming and biofilm cell states. Minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively) were determined via common methods with novel application of statistical approaches combining random effects models and interval censored data to estimate uncertainties. The MICs and MBCs for planktonic and biofilm-forming states ranged from 3.12 to 12.5 μg ml?1, with biofilm values only ≈ 8 times higher. Potent anti-biofilm activity and reactive structural features make QPS-1 a promising antibacterial additive for dental and potentially other biomedical devices. Together, the experimental framework and statistical models provide estimates and uncertainties for effective antimicrobial concentrations in multiple cell states, enabling statistical comparisons and improved characterization of antibacterial agents.  相似文献   

13.
李亮  尚晓冬  谭琦 《菌物学报》2015,34(6):1176-1186
本研究以甲硝唑为阳性对照,利用HPD-100大孔树脂和95%乙醇将猴头菌子实体中小分子活性物质进行富集,得到乙醇制备液(MREEs);然后对乙醇制备液分别使用石油醚(60-90℃)和氯仿进行多次萃取,得到石油醚萃取物(A1、A2)和氯仿萃取物(B),并进行GC-MS测定;对MREEs和A1、A2、B分别进行药敏试验,同时对5种幽门螺旋杆菌进行最低抑菌浓度测定。结果表明,使用大孔树脂得到的MREEs有较好的抑菌活性,得到的A1、A2和B对幽门螺旋杆菌的抑菌率均高于40.0%,其中石油醚萃取物A1在Helicobacter pylori SSI中的抑菌率甚至高达62.9%;A1、A2和B使用GC-MS测定出的主要成分分别是邻苯二甲酸二丁酯(A1,4.53%和A2,6.93%)和棕榈酸2.87%,但仍有大量成分没有被测出。另外,在最低抑菌浓度试验中,A1相应组分对Helicobacter pylori W2504、Helicobacter pylori 9和Helicobacter pylori ATCC 43504的最低抑菌浓度都为0.25mg/mL,A2对Helicobacter pylori 78的最低抑菌浓度仅为0.25mg/mL,而B对Helicobacter pylori W2504、Helicobacter pylori 9的最低抑菌浓度均仅为0.125mg/mL,说明通过石油醚和氯仿萃取得到的猴头菌子实体提取物对幽门螺旋杆菌具有潜在的抑菌作用。  相似文献   

14.
In a screening program for new antibiotic producers, a strain of Aspergillus fumigatus was isolated from Brazilian soil samples. A pool of autoclaved bacteria was added to part of the fungus culture on the second day of fermentation to increase antibiotic production. The chloroform extract from the culture broth to which the pool of autoclaved bacteria was added showed an increase of 55%, 63% and more than 100% in activity against Staphylococcus aureus, Candida albicans and Micrococcus luteus, respectively. Also, the HPLC chromatographic profiles of the chloroform extracts from both culture conditions were different. Two active compounds were isolated from the broth of the culture grown in the presence of pooled bacteria and were identified as 3,4-dimethoxyphenol and 1,3,5-trimethoxybenzene.  相似文献   

15.
张铁焕  吴玉霞  奠佐红  左国营 《广西植物》2020,40(12):1712-1720
为考察19种中药材乙醇提取物的体外抗临床常见致病菌的活性,该文将中药粗粉用80%乙醇浸泡提取,提取液减压浓缩制备成浸膏,采用琼脂打孔法测定提取物抑菌圈,通过微量倍比稀释法测定最低抑菌浓度(MIC)和最低杀菌浓度(MBC/MFC)。结果表明:所筛选的19种中药材乙醇提取物对不同的菌株具有不同程度的抑制作用,14种中药材乙醇提取物抗SA、EC、PA和CA的抑菌圈范围在8~27 mm之间,其中地锦草、四块瓦、三颗针、马尾黄连和土大黄的提取物抗SA、EC的抑菌圈范围在10.3~26.6 mm之间。马尾黄连、孜然、地锦草、广西莪术、穿心莲、益母草、吴茱萸、土大黄、叶上花、土连翘、凤尾草和三颗针的醇提物对MRSA和铜绿假单胞菌耐药菌均具有显著的抗微生物活性,其MIC/MBC值在391~6 250μg·m L-1之间;地锦草、三颗针抗MRSA的最低MIC值分别为391、781μg·m L-1,抗PA耐药菌的最低MIC值均为1 562.5μg·m L-1;马尾黄连、孜然和三颗针的醇提物对白色念珠菌耐药菌有中等抑制作用,杀菌效果不明显。该...  相似文献   

16.
The hexane, ethyl acetate, dichloromethane, methanol extracts and spent media (extracellular substances) were tested in vitro for their antibacterial activity for which one Gram-positive bacterium (Staphylococcus aureus) and four Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumoniae) were used as test organisms. The methanol extract showed more potent activity than other organic extracts, spent medium of the culture exhibited little activity against E. coli only. No inhibitory effect was found against Klebsiella pneumoniae.The broth microdilution assay gave minimum inhibitory concentrations (MIC) values ranging from 1 to 512 μg/ml. The MIC of methanol extract against S. aureus and E. coli were 128 μg/ml and 256 μg/ml, respectively.  相似文献   

17.
《Microbiological research》2014,169(4):287-293
Quinoxaline is a chemical compound that presents a structure that is similar to quinolone antibiotics. The present work reports the study of the antimicrobial activity of quinoxaline N,N-dioxide and some derivatives against bacterial and yeast strains. The compounds studied were quinoxaline-1,4-dioxide (QNX), 2-methylquinoxaline-1,4-dioxide (2MQNX), 2-methyl-3-benzoylquinoxaline-1,4-dioxide (2M3BenzoylQNX), 2-methyl-3-benzylquinoxaline-1,4-dioxide (2M3BQNX), 2-amino-3-cyanoquinoxaline-1,4-dioxide (2A3CQNX), 3-methyl-2-quinoxalinecarboxamide-1,4-dioxide (3M2QNXC), 2-hydroxyphenazine-N,N-dioxide (2HF) and 3-methyl-N-(2-methylphenyl)quinoxalinecarboxamide-1,4-dioxide (3MN(2MF)QNXC). The prokaryotic strains used were Staphylococcus aureus ATCC 6538, S. aureus ATCC 6538P, S. aureus ATCC 29213, Escherichia coli ATCC 25922, E. coli S3R9, E. coli S3R22, E. coli TEM-1 CTX-M9, E. coli TEM-1, E. coli AmpC Mox-2, E. coli CTX-M2 e E. coli CTX-M9. The Candida albicans ATCC 10231 and Saccharomyces cerevisiae PYCC 4072 were used as eukaryotic strains. For the compounds that presented activity using the disk diffusion method, the minimum inhibitory concentration (MIC) was determined. The alterations of cellular viability were evaluated in a time-course assay. Death curves for bacteria and growth curves for S. cerevisiae PYCC 4072 were also accessed. The results obtained suggest potential new drugs for antimicrobial activity chemotherapy since the MIC's determined present low values and cellular viability tests show the complete elimination of the bacterial strain. Also, the cellular viability tests for the eukaryotic model, S. cerevisiae, indicate low toxicity for the compounds tested.  相似文献   

18.
Phenological and some biological characteristics of Hippodamia (Adonia) variegata (Goeze) (Coleoptera: Coccinellidae), such as voltinism, hibernation, number of progeny produced by each generation, mating activity and sex ratio were studied, in order to evaluate the significance of this predator. The study of phenology was conducted in outdoor cages in Kifissia (Athens), during 1999--2001 and as prey was given Dysaphis crataegi (Kaltenbach). Hippodamia variegata completed seven generations between April and November. The hibernating population of H. variegata consisted of adults of 6th and 7th generations. The fecundity of the predator was studied under constant conditions [25 °C, 65% R.H. and 16:8(L:D)h photoperiod] in the laboratory and some population parameters were calculated: The total fecundity ranged between 789 and 1256 eggs, while the mean total fecundity was 959.6 eggs. The greatest proportion of eggs (45%) was oviposited in clutches of 11--20 eggs. The net reproductive value (R0) was found to be 425.9 females/female, the intrinsic rate of increase (rm) 0.178 females/female/day and the mean generation time (T) 34.0 days.  相似文献   

19.
Pan W  Liu X  Ge F  Zheng T 《Journal of biosciences》2003,28(6):723-731
A novel tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) was used in the assessment of antimicrobial activity in earthworm in the presence of phenazine methosulphate (PMS) as an electron coupling reagent. This activity was purified from the coelomic fluid of the earthworm (ECF),Eisenia fetida andrei (Oligochaeta, Lumbricidae, annelids) using a series of column chromatography techniques and was tested against three Gram-negative strains ofEscherichia coli, Pseudomonas aeruginosa, Aeromonas hydrophila and three Gram-positive strains ofStaphylococcus aureus, Bacillus megaterium, Arthrobacter sp., respectively. Only the pigment-free eluate of coelomic fluid of the earthworm (ECFPE) showed activity againstB. megaterium amongst three isolated active fractions. The anion (DEAE-52) exchange effluent of the ECFPE was reported to have the strongest activity againstP. aeruginosa amongst the three active fractions. The 20% acetonitrile eluate (AE) by Sep-Pak C18 cartridge was also tested and showed fair resistance againstE. coli, P. aeruginosa andArthrobacter sp., respectively.  相似文献   

20.
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