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Biomedical subjects

K G Gupta

Publications and source records attributed to K G Gupta.

At least 19 recordsLinked to original sources
PubMed2000

Rapid degradation of ferulic acid via 4-vinylguaiacol and vanillin by a newly isolated strain of bacillus coagulans.

A new strain Bacillus coagulans BK07 was isolated from decomposed wood-bark, based on its ability to grow on ferulic acid as a sole carbon source. This strain rapidly decarboxylated ferulic acid to 4-vinylguaiacol, which was immediately converted to vanillin and then oxidized to vanillic acid. Vanillic acid was further demethylated to protocatechuic acid. Above 95% substrate degradation was obtained within 7 h of growth on ferulic acid medium, which is the shortest period of time reported to date. The major degradation products, was isolated and identified by thin-layer chromatography, high performance liquid chromatography and 1H-nuclear magnetic resonance spectroscopy were 4-vinylguaiacol, vanillin, vanillic acid and protocatechuic acid.

Bacillus↗
PubMed1992

Lytic effect of Bacillus subtilis elastase on gram-positive and negative bacteria.

Elastase of B. subtilis 6a caused lysis of freshly grown cells of Gram-negative (Proteus vulgaris, Klebsiella pneumoniae, Salmonella typhi and Pseudomonas aeruginosa and Gram-positive (B. subtilis) bacteria. Heat killed and lyophilised Gram-positive and negative bacteria showed higher sensitivity to elastase. Both Gram-negative and Gram-positive bacteria were lysed maximally by elastase at pH 8.0. At this pH, activity of elastase was maximum in Tris-HCl and glycine-NaOH buffers followed by Tris-maleate and cacodylate buffers.

Bacillus subtilis↗
PubMed1990

Lytic effect of Vibrio cholerae elastase on gram-positive and -negative bacteria.

Elastase of Vibrio cholerae caused the lysis of freshly grown cells of Gram-negative (Pseudomonas aeruginosa, Proteus vulgaris, Salmonella paratyphi A and Klebsiella pneumoniae) bacteria. Gram-positive (Staphylococcus aureus and S. epidermidis) organisms were resistant to this enzyme. Heat killed and lyophilized Gram-positive and -negative bacteria (except S. aureus and S. epidermidis) showed higher sensitivity to elastase. Both Gram-negative and -positive bacteria were lyzed maximally by elastase at pH 8.0. At this pH, lytic activity of elastase was maximum in Tris-HCl and glycine-NaOH buffers followed by Tris-maleate and cacodylate buffers.

Bacteriolysis↗
PubMed1990

Use of a modified cupric acetate method for the detection and quantitation of xylanolytic activities: a comparative study with the congo red method.

A modified cupric acetate method for the screening and quantitation of xylanolytic activities was comparable with the more widely used congo red method with respect to sensitivity and ease of use and was shown to have points of merit over the latter. The use of a non-linear correction, in comparison to the conventional linear one, for the effect of dilution on the quantitative plate assay was evaluated.

Bacillus↗
PubMed1990

Purification of 7 alpha-hydroxysteroid dehydrogenase from Escherichia coli strain 080.

Purification studies of 7 alpha-hydroxysteroid dehydrogenase (7 alpha-HSDH) (EC 1.1.1.159) from Escherichia coli 080 showed that 1.59-fold purification could be achieved by heating (60 degrees C for 10 min) the ultracentrifuged enzyme preparation, and 6.46-fold purification was achieved by subsequent precipitation with ammonium sulfate. Further purification on Sephadex G-100 gel gave 10.1-fold purification. After pooling and concentrating the active fractions obtained from the Sephadex G-100 filtration, an 11.1-fold purification was achieved using DEAE-cellulose chromatography. The purified enzyme produced a single band on polyacrylamide gel electrophoresis and its molecular weight was determined to be 54,000. The enzyme was immunogenic and showed immunoprecipitation with homologus antisera.

Chromatography, DEAE-Cellulose↗
PubMed1990

Optimization of 7 alpha-hydroxysteroid dehydrogenase production by Escherichia coli 080.

7 alpha-Hydroxysteroid dehydrogenase (EC 1.1.1.159) production by Escherichia coli strain 080 was highest when the organism was grown in brain heart infusion broth at pH 6.5 for 72-96 h with shaking at 37 degrees C. The oxygen consumption rate had a strong effect on the production of this constitutive enzyme. Glucose and lactose at 0.2-0.4%, detergents, and ethylenediaminetetra-acetic acid were found to increase the enzyme production.

Culture Media↗
PubMed1989

Entrapment of venous catheter following inferior vena caval spasm.

This is a report of a case in which a 5F high-flow right coronary catheter with its guide wire was entrapped within the inferior vena cava following a venous spasm. Local infusion of nitroglycerin (NTG) relieved the spasm, and the guidewire-catheter assembly could be safely retrieved.

Cardiac Catheterization↗
PubMed1989

Lytic effect of Pseudomonas aeruginosa elastase on gram-positive and -negative bacteria.

Elastase of Pseudomonas aeruginosa P3 caused lysis of freshly grown cells of Gram-positive (Staphylococcus aureus and S. epidermidis) and Gram-negative (Proteus vulgaris and Salmonella typhi) bacteria. Heat killed and lyophilized Gram-negative bacteria showed higher sensitivity to elastase. Both Gram-negative and Gram-positive bacteria were lysed maximally by elastase at pH 8.0. At this pH, the activity of elastase was maximal in Tris-HCl and glycine-NaOH buffers followed by Tris-maleate and Cacodylate buffers.

Bacteriolysis↗
PubMed1989

Production and partial characterization of elastase of Vibrio cholerae Inaba.

Conditions are described for the production of extracellular elastase by Vibrio cholerae Inaba 2/57. The yield of the enzyme was maximum in shake cultures grown in alkaline peptone water at 37 degrees C and was stable in culture supernatants. The enzyme, partially purified by ammonium sulphate precipitation and Sephadex G-100 gel filtration showed a molecular weight of 30,000 and an activity between pH 5.0-8.0 with an optimum of 8.0 in Tris-maleate buffer. The elastinolytic activity was maximal in glycine-NaOH buffer and minimal in phosphate buffer. The enzyme activity was adversely affected by temperature greater than or equal to 40 degrees C.

Chromatography, Gel↗
PubMed1989

Induction of mixed function oxidase activities of protein A in rat mammary tumors.

Following s.c. administration of purified protein A, to 7,12-dimethylbenz(alpha)anthracene-induced mammary-tumor-bearing rats, a regenerated metabolism of the carcinogen was observed. The antitumor effect of protein A was evident from the decrease in tumor volume. The phase I and phase II enzyme activities suggest that protein A has the ability to induce the mixed function oxidases activity, which are active in the metabolism of xenobiotics.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1989

Kinetic properties of 7 alpha-hydroxysteroid dehydrogenase from Escherichia coli 080.

Results on the kinetics of 7 alpha-hydroxysteroid dehydrogenase 7 alpha-HSDH showed that this enzyme could oxidize all bile acids having an -OH group at the C-7 position. Lineweaver-Burk plots showed Michaelis constant (Km) values of 0.83 and 0.12 mM for cholic acid and chenodeoxycholic acid, respectively. The effect of enzyme concentration on the reaction velocity showed a constant increase in the enzyme activity with increase in enzyme-protein concentration. 7 alpha-HSDH was activated by Na+, K+, Ca2+, and Mn2+ ions and by reducing agents having a thiol group (dithiothreitol, 2-mercaptoethanol). Co2+, Hg2+, Fe3+, Mg2+, Zn2+, Ba2+, and Cu2+ ions, chelating agents (potassium oxalate, heparin, EDTA) oxidizing agents (sodium perchlorate, sodium periodate, sodium persulphate), and detergents (Tween 20, Tween 40, Tween 80, Triton X-100, sodium lauryl sulphate) were inhibitory to 7 alpha-HSDH activity.

Bile Acids and Salts↗
PubMed1988

Bacteriology of the cervix in cases of infertility: effect on human and animal spermatozoa and role of elastase.

Microorganisms such as Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans isolated from cervices of infertile human females inhibited motility and agglutinated human, cow bull, buffalo bull, and rat spermatozoa in vitro. Fifty percent of the infertile females studied carried elastase-positive microorganisms. Cell-free culture supernatants of 72-hr-old elastase-positive cultures were spermicidal within 60 min of contact with sperm, while elastase-negative cultures were spermicidal in 4-6 hr. Cultures of all the cervical isolates were spermicidal and agglutinated human, cow bull, buffalo bull, and rat spermatozoa, and these activities increased with age of the culture. Human sperm showed only tail-to-tail agglutination, while cow bull, buffalo bull, and rat spermatozoa showed mainly head-to-head agglutination. Spermicidal activity was also attributable to elastase, which was present more in 72-hr-old cultures than in 24-hr-old cultures.

Agglutination↗
PubMed1988

Production and partial characterization of elastase of Bacillus subtilis isolated from the cervices of human females.

Conditions are described for the production of extracellular elastase by Bacillus subtilis. The yield of enzyme was maximum in shake-cultures grown in Syncase medium at 37 degrees C and was stable in culture supernatants. The enzyme, purified by ammonium sulphate precipitation and Sephadex G-75 gel filtration, showed a molecular weight of 25,000 and activity between pH 6.0 and 9.5, with an optimum of 9.0 in Tris-maleate buffer. Elastinolytic activity was maximum in glycine-NaOH buffer and minimum in phosphate buffer. Enzyme activity was adversely affected by temperature greater than or equal to 40 degrees C.

Bacillus subtilis↗
PubMed1986

Effect of dithiocarbamates on citric acid production by Aspergillus niger.

Dithiocarbamates were found to enhance the production of citric acid under solid-state fermentation conditions by Aspergillus niger. Maximum increase was observed with tetramethylthiuram disulfide (TMTD). Percent increases observed were 74.2% with 2.5 micrograms/mL of TMTD, 19.6% with 2.5 micrograms/mL of sodium dimethyldithiocarbamate and 33.1% with 0.6 micrograms/mL of zinc dimethyldithiocarbamate.

Aspergillus niger↗
PubMed1986

Bacteriology of cervix in cases of infertility: effect on human sperm.

Microorganisms such as Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis isolated from cervices of infertile females possessed spermicidal activity. They also agglutinated the human spermatozoa in vitro and showed tail-to-tail agglutination. Cell-free supernatant of these organisms was found to be spermicidal but did not agglutinate spermatozoa in vitro. Spermicidal activity was increased with increase in age of the culture.

Bacterial Physiological Phenomena↗