effects of temperature and percentage of organic modifier were studied on retention and selectivity in rp-hplc using solvation parameter model. the system constants were determined by multiple linear regression analysis from experimental values in the retention factor for a group of different solutes with known descriptors by computer using the program spss/pc. the experimental results showed t...

Six components of new cephem antibiotics, cephabacin M1-6, were isolated from the culture filtrate of Xanthomonas lactamgena YK-431 by various types of column chromatographies and preparative reverse-phase HPLC. Their structures were determined by spectroscopic analyses and degradation studies. They consist of 7-methoxydeacetylcephalosporin C as a nucleus and a tri- to heptapeptide including a ...

In a previous study, we identified a Streptomyces sp., A3265, as exhibiting potent antifungal activity against various plant pathogenic fungi, including Botrytis cinerea, Colletotrichum gloeosporioides, and Rhizoctonia solani. This strain also exhibited a biocontrolling effect against ginseng root rot and damping-off disease, common diseases of ginseng and other crops. In this study, we isolate...

Class separation of methylated free bile acids from bile acids conjugated with taurine and methylglycine was accomplished using a solvent system of 2,2,4-trimethylpentane-absolute ethanol 10:1 (v/v). By developing a silica thin-layer plate two times with solvent in a Brinkmann sandwich tank, the difficult resolution between methyl cholate and methyl glycolithocholate was achieved. Evidence is p...

2156 CLINICALCHEMISTRY, Vol. 34, No. 10, 1988 3. Gundert-Remy N, DeVries JX. Determination of ureidopemcillins azlocillin, mezlocillin, and Bay K 4999 in plasma by high performance liquid chromatography. Br J Clin Pharmacol 1979;8:589-92. 4. Fasching CE, Peterson LR. High-pressure liquid chromatographic assay of azlocillinand meziocillinwith an anion-exchange extractiontechnique.J Liq Chromatog...

The purpose of this research project is to identify and chemically profile active extracts of a marine sponge, Clathria sp., collected from St. Thomas, US Virgin Islands. Previously, pteridine alkaloids, sterol sulfates, and bromine-containing amides collected from various species of Clathria have shown anti-microbial and anti-cancer activities [1]. Sponge extracts were isolated through a combi...

2156 CLINICALCHEMISTRY, Vol. 34, No. 10, 1988 3. Gundert-Remy N, DeVries JX. Determination of ureidopemcillins azlocillin, mezlocillin, and Bay K 4999 in plasma by high performance liquid chromatography. Br J Clin Pharmacol 1979;8:589-92. 4. Fasching CE, Peterson LR. High-pressure liquid chromatographic assay of azlocillinand meziocillinwith an anion-exchange extractiontechnique.J Liq Chromatog...