Ján Fuska

Effect of colicin e3 on leukemia cells p388 in vitro.

Proliferation of murine leukemia cells P388 is stimulated by less than 1.0 mg/ml colicin E3, while being inhibited by higher concentrations. By 1.6 mg/ml colicin E3, uptake of thymidine into cold TCA-precipitable fraction is decreased by 59% during 24 h, uptake of uridine by 29%.

2-Methylsorbic acid, an antifungal metabolite of Penicillium vermiculatum

Summary2-Methylsorbic acid (MA), (2Z,4E)-2-methyl-2,4-hexadienoic acid, is a new metabolite of Penicillium vermiculatum. Antifungal activity of this acid was higher than that of sorbic acid or the bromoderivatives bromomethylsorbic acid and bromosorbic acid. MA suppressed the growth of Talaromyces flavus and germination of its conidia. In P. vermiculatum this acid lowered production of vermiculin and inhibited proteosynthesis in Saccharomyces cerevisiae.

The effects of some tetracycline derivates on Ehrlich ascites carcinoma and HeLa cells in vitro

In-vitro-Nachweis der Hemmung der Proteo- und Nukleosynthese in den EAC-Zellen, sowie des Wachstums der HeLa-Zellen mit folgenden Derivaten des Tetrazyklins: Anhydrotetrazyklin, 4α, 12α-Anhydrodedimethylaminotetrazyklin und 12α-Deoxydedimethylaminotetrazyklin.

Vermilutin, a xanthone from Penicillium vermiculatum

Abstract Vermilutin, 8-formyl-1-hydroxy-6-methyl-4-(3-methylbut-1-enyl)xanthone, was isolated from the mycelium of Penicillium vermiculatum and its structure deduced from spectral data. Vermilutin and its acetate inhibited the biochemical function of in vitro grown P388 lympholeukemic cells.

Microbial transformations of cardioglycosides

SummaryPenicillium vermiculatum deglycosylated lanatosid C to acetyldigoxin and Arthrobacter citreus deacetylated the latter to digoxin. Both reactions were carried out in a short time with high yields. Lanatosid A was transformed by P. vermiculatum simultaneously to acetyldigitoxin and digitoxin. A. citreus transformed lanatosid A directly to digitoxin and lanatosid C to digoxin, but the reactions took a long time and the yields were low.

Hydrogenation of vermistatin

SummaryHydrogenation of vermistatin, a metabolite ofPenicillium vermiculatum, affordedcis- andtrans-3-(2′-carboxy-4′,6′-dimethoxybenzyl)-6-propyltetrahydro-4H-pyran-4-one and 4,6-dimethoxy-3-(4′-propylcyclopentanon-2′-yl)phthalide. The latter compound was found to be the strongest inhibitor of RNA synthesis in P 388 leukemia cells of all compounds tested.ZusammenfassungBei der Hydrierung von Vermistatin, einem neuen sekundären Metabolit ausPenicillium vermiculatum, wurdencis- undtrans 3-(2′-Carboxy-4′,6′-dimethoxybenzyl)-6-propyltetrahydro-4-pyran-4-on und 4,6-dimethoxy-3-(4′-propylcyclopentanon-2′-yl)phthalid erhalten und spektroskopisch charakterisiert. Die letztgenannte Verbindung zeigte von allen getesteten Verbindungen die stärkste Hemmwirkung auf die RNA Synthese in P 388 Leukämiezellen.

Microbial transformation of 2,3-dihydro-3-methoxywithaferin-A by Cunninghamella elegans

Abstract Cunninghamella elegans (NRRL 1393) transformed 2,3-dihydro-3-methoxywithaferin-A to 2,3-dihydro-12β-hydroxy-3-methoxywithaferin-A. Both compounds inhibited the growth and biochemical functions of in vitro grown P388 lympholeukemic cells.

Biotransformation of benzyl thiocyanate by Streptomyces aureofaciens

Benzyl thiocyanate, a specific stimulator of chlortetracycline biosynthesis, was transformed into dibenzyl disulphide by Streptomyces aureofaciens. The disulphide stimulated chlortetracycline production to a lesser extent than did benzyl thiocyanate.

New Method for Screening the Inhibitors of Wood-Damaging Fungi

This new elaborated method is based on the evaluation of the Inhibition of the incorporation of C adenine and C L-valine into the trichloracetic acid insoluble fractions of the tested microorganisms.This method was verified using the microorganisms: Aureobasidium pullulans, Cladosporium sphaerospermum and Ceratocystis pilifera. Pentachlorophenol (PCP) and tributyltinoxide (TBTO), were used s inhibitors. PCP was more effective thanTBTO, both substances inhibited more the utilization of L-valine than of adenine.The inhibitory effect of forty microbial filtrates was also evaluated by this method. Some of them evidently inhibited microbial models used.

Identification and determination of organic acids in cultivation medium ofPenicillium vermiculatum dang

Summary[2E,7E]-4,9-dioxo-2,7-decadienoic, [2E,7E]-9-oxo-2,7-decadienoic and [2Z,4E]-2-methyl-2,4-hexadienoic acids were isolated from the filtrate ofPenicillium vermiculatum Dang. The presence of [2E,2′E,7S,7′E]-4,9-dioxo-7-(4′,9′-dioxo-2′,7′-decadienoyloxy)-2-decenoic acid was confirmed by chromatography. HPLC was used for the determination of these acids in the cultivation medium.Zusammenfassung[2E,7E]-4,9-dioxo-2,7-decadiensäure, [2E,7E]-9-oxo-2,7-decadiensäure und [2Z,4E]-2-methyl-2,4-hexa-diensäure wurden aus dem Kultivierungsmedium vonPenicillium vermiculatum Dang isoliert. Die Anwesenheit von [2E,2′E,7S,7′E]-4,9-dioxo-7-(4′,9′-dioxo-2′,7′-decadienoyloxy)-2-decensäure wurde chromatographisch bestätigt, Im Filtrat vonP. vermiculatum wurden diese Säuren mittels HPLC analysiert.