ABSTRACT
As marine environmental conditions are extremely different from terrestrial ones, it is surmised that marine actino-mycetes might produce novel bioactive compounds. Hence marine sediments, collected from the coastal areas of Gokharna and Muradeshwara of Karnataka state, were screened Seventeen isolates were obtained on starch-casein agar media by soil dilution technique. However, only six isolates namely ACT-A2, ACT-A3, ACT-A4, ACT-A5, ACT-A7 and ACT-A15 showed significant antibacterial activity against both gram-positive and gram-negative bacteria. Morphological, cultural and biochemical characterization indicated that the isolates belong to Streptomyces genus of Actinomycetes. Further studies were carried out with the most active ACT-A2. Optimization of media, temperature and pH by shake flask fermentation indicated starch-casein, 28°C and 7 to be suitable for ACT-A2. The production of antibiotics began after 24 h, reached maximum at 72 h and maintained at the same level up to 120 h. Ethyl acetate was used to extract antibacterial compounds from the culture filtrate. TLC was done on silica gel using ethyl acetate: methanol (6:4) and direct bioautography has shown the presence of two active substance, one with Rf 0.8 has more activity than the other with Rf 0.4. Further purification is done by column chromatography using a mixture of dicholoromethane and ethyl acetate. The findings from this investigation reveal that the strain ACT-A2 in order exhibited superior antimicrobial activities to other sediment isolates of actinomycetes.
ABSTRACT
As marine environmental conditions are extremely different from terrestrial ones, it is surmised that marine actino-mycetes might produce novel bioactive compounds. Hence marine sediments, collected from the coastal areas of Gokharna and Muradeshwara of Karnataka state, were screened Seventeen isolates were obtained on starch-casein agar media by soil dilution technique. However, only six isolates namely ACT-A2, ACT-A3, ACT-A4, ACT-A5, ACT-A7 and ACT-A15 showed significant antibacterial activity against both gram-positive and gram-negative bacteria. Morphological, cultural and biochemical characterization indicated that the isolates belong to Streptomyces genus of Actinomycetes. Further studies were carried out with the most active ACT-A2. Optimization of media, temperature and pH by shake flask fermentation indicated starch-casein, 28°C and 7 to be suitable for ACT-A2. The production of antibiotics began after 24 h, reached maximum at 72 h and maintained at the same level up to 120 h. Ethyl acetate was used to extract antibacterial compounds from the culture filtrate. TLC was done on silica gel using ethyl acetate: methanol (6:4) and direct bioautography has shown the presence of two active substance, one with Rf 0.8 has more activity than the other with Rf 0.4. Further purification is done by column chromatography using a mixture of dicholoromethane and ethyl acetate. The findings from this investigation reveal that the strain ACT-A2 in order exhibited superior antimicrobial activities to other sediment isolates of actinomycetes.
ABSTRACT
The pharmacokinetics of 16-dehydropregnenolone （16-DHP）, a sterols compound isolated from Solanum lyratum Thunb., was investigated in rats following a single intramuscular administration （40 mg/kg）. The concentration of 16-DHP in rat plasma was determined by a high performance liquid chromatography （HPLC） method with UV detection. Levonorgestrel was used as the internal standard （IS）. The pharmacokinetic parameters of 16-DHP were derived by non-compartmental method. After a single intramuscular administration, the maximum plasma concentration （Cmax） was （289±25）ng/mL, time to reach Cmax（tmax） was （0.38±0.14） h, the elimination half-life （t1/z） was （2.5±1.1）h, the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration （AUC（0-t）） was （544± 73）ng· h/mL. The results indicated that 16-DHP was absorbed quickly and eliminated rapidly in rats after the intramuscular injection.
ABSTRACT
The TLC UV scanning assay for tanshinone IIA and cryptotanshinone in Yangxuezhitong pills was built up.Their wave lengths were 260 nm and 255 nm respectively.The regressive equation and coefficient of corelation were Y=40.48+5526.90X,r=0.9995 and Y=-12.91+5640.48X,r=0.9999 respectively.The recovery ratio of cryptotanshinone was(?)=102.62%.This me- thod is simple and convenient,and elicits accurate and reproduceable results.