Bacterial Biotransformation and Anticancer Activities of Betulin against A549, HepG2 and 5RP7 Cancer Cell Lines.

BACKGROUND: A pentacyclic lupenane-type natural triterpenoid, betulin, has attracted attention in the field of medicinal chemistry since it exhibited a variety of biological activities, including anticancer activity. OBJECTIVE: The aim of this present work was to obtain derivatives of betulin through bacterial biotransformation and investigate its anticancer activity against A549, HepG2 and 5RP7 cancer cell lines. METHODS: Bacterial biotransformation studies were continued in an MBH broth medium for 7 days at 35oC. Anticancer activities of betulin against A549, HepG2 and 5RP7 cell lines were carried out using XTT assay, and their selectivity was determined using a healthy cell line of NIH/3T3. Cell proliferation ELISA, BRDU (colorimetric) assay was used for measuring proliferation in replicative cells in which DNA synthesis occurs. Flow cytometric analysis was used for measuring apoptotic cell percentages, caspase 3 activation and mitochondrial membrane potential. RESULTS: Bacterial biotransformation studies with 7 bacteria of Staphylococcus aureus ATCC 6538, Proteus vulgaris NRRL B-123, Bacillus subtilis NRRL B-4378, Streptomyces griseolus NRRL B-1062, Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 43300 and Bacillus velezensis NRRL B-14580 produced no metabolite. In in vitro anticancer activity studies, betulin was found to exert anticancer activity against A549, HepG2 and 5RP7 cell lines with IC50 values of 207.7, 125.0 and 28.3 µg/mL, whereas SI values were found to be 30, 50 and 223, respectively. Early and late apoptotic percentages of betulin were found as 9.6, 12.1 and 85.4% on A549, HepG2 and 5RP7, respectively, while caspase 3 positive cell percentages were 2.3, 28.7 and 13.3% for IC50 concentrations. In addition, betulin caused G1 cell cycle arrest (49.5%) on 5RP7 cell line. CONCLUSION: The results have been shown that betulin activities against A549 and HepG2 cell lines were nonselective and limited its cytotoxic activity against healthy cells, but it is possible to say that it exerted selective activity against 5RP7 cell (28.33±1.53 µg/mL). Betulin effects on apoptosis were found to be dosedependent, while its effect on caspase 3 activation, mitochondrial membrane potential, and cell cycle arrest on G0/G1 phase was not dependent on doses. Therefore, betulin could be a good candidate for the treatment of H-ras active cancer types.

The protective effects of demethoxyviridine and 1-alpha-hydroxy-demethoxyviridine in the livers of male rats treated with diethylnitrosamine and 2-acetylaminflourene.

OBJECTIVE: To determine the protective effects of a fungal metabolite of demethoxyviridine (DMV) and its derivative, 1-alpha-hydroxy-DMV in the livers of 2-month-old male Spraque-Dawley rats treated with diethylnitrosamine (DEN) and 2-acetylaminflourene (2-AAF). METHODS: This study was performed in the Department of Medical Biology, Faculty of Medicine, Eskisehir Osmangazi University, Eskisehir, Turkey from May 2006. Animals were divided into 10 groups. Those were the control, olive oil, dimethyl sulfoxide (DMSO), DMV, 1-alpha-hydroxy-DMV, DEN, 2-AAF, DEN+2-AAF, DEN+2-AAF+DMV, and DEN+2-AAF+1-alpha-hydroxy-DMV-treated animal groups. The liver microsomes were prepared from rats and the levels of expression of cytochrome P450 1A2 (CYP1A2) enzymes were determined with western blot technique. The liver tissue slides were evaluated histopathologically with hematoxylin and eosin staining and immunohistochemically for Harvey-retrovirus associated DNA sequences (Ha-Ras), glutathione S- transferase (GST-p), and connexion-32 (Cx32) proteins. RESULTS: Notably, there were no appreciable differences in CYP1A2 level among control, olive oil, and DMSO-treated animals. The CYP1A2 level was significantly decreased in 2-AAF, DEN+2-AAF, DEN, DEN+2-AAF+DMV, DEN+2-AAF+1-alpha-hydroxy-DMV, 1-alpha-hydroxy-DMV, and DMV-treated animals as compared to the control. Most prenoplastic focus was found in DEN+2-AAF treated group. CONCLUSION: Demethoxyviridine and 1-alpha-hidroksi-DMV had protective effect in the livers of DEN, 2-AAF and DEN+2-AAF induced rats.

Biosorption of Reactive Black 5 dye by Penicillium restrictum: the kinetic study.

Biosorption of Reactive Black 5 (RB 5) dye onto dried Penicillium restrictum biomass was studied with respect to pH, contact time, biosorbent and dye concentrations. The effect of temperature on the biosorption efficiency was also carried out and the kinetic parameters were determined. Optimum initial pH, equilibrium time and biomass concentration for RB 5 dye were found to be 1.0, 75 min and 0.4 g dm(-3) at 20 degrees C, respectively. The maximum biosorption capacities (q(max)) of RB 5 dye onto dried P. restrictum biomass were 98.33 and 112.50mg (g biomass)(-1) at 175 mg dm(-3) initial dye concentration at 20 and 50 degrees C, respectively, and it was 142.04 mg (g biomass)(-1) at 200 mg dm(-3) initial dye concentration at 35 degrees C. The results indicate that the biosorption process obeys a pseudo-second-order kinetic model.

Cytotoxic, Antiproliferative and Apoptotic Effects of Perillyl Alcohol and Its Biotransformation Metabolite on A549 and HepG2 Cancer Cell Lines.

BACKGROUND: A monoterpene, perillyl alcohol, has attracted attention in medicinal chemistry since it exhibited chemo-preventive and therapeutic properties against a variety of cancers. OBJECTIVE: In the present work, it was aimed to obtain derivatives of perillyl alcohol through microbial biotransformation and investigate their anticancer activities against A549 and HepG2 cancer cell lines. METHOD: Biotransformation studies were carried out in a α-medium for 7 days at 25oC. XTT assay was performed to investigate the anticancer activities of perillyl alcohol and its biotransformation metabolite, dehydroperillic acid, against A549 and HepG2 cell lines and their selectivity using healthy cell line, NIH/3T3. Cell proliferation ELISA, BRDU (colorimetric) assay was used for measurement of proliferation in replicative cells in which DNA synthesis occurs. Flow cytometric analyses were also carried out for measuring apoptotic cell percentages, caspase 3 activation and mitochondrial membrane potential. RESULTS: Biotransformation of perillyl alcohol with Fusarium culmorum yielded dehydroperillic acid in a yield of 20.4 %. In in vitro anticancer studies, perillyl alcohol was found to exert cytotoxicity against HepG2 cell line with an IC50 value of 409.2 µg/mL. However, this effect was not found to be selective because of its higher IC50 (250 µg/mL) value against NIH/3T3 cell line. On the other hand, dehydroperillic acid was found to be effective and also selective against A549 cell line with an IC50 value of 125 µg/mL and a selectivity index (SI) value of 400. Apoptosis inducing effects of dehydroperillic acid was better in A549 cell line. CONCLUSION: Dehydroperillic acid may be a good candidate for therapy of lung adenocarcinoma and may show this anticancer activity by inducing apoptosis.

Determination of the equilibrium, kinetic and thermodynamic parameters of adsorption of copper(II) ions onto seeds of Capsicum annuum.

Adsorption of copper ions onto Capsicum annuum (red pepper) seeds was investigated with the variation in the parameters of pH, contact time, adsorbent and copper(II) concentrations and temperature. The nature of the possible adsorbent and metal ion interactions was examined by the FTIR technique. The copper(II) adsorption equilibrium was attained within 60 min. Adsorption of copper(II) ions onto C. annuum seeds followed by the Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherm models. Maximum adsorption capacity (q(max)) of copper(II) ions onto red pepper seeds was 4.47x10(-4) molg(-1) at 50 degrees C. Three kinetic models including the pseudo-first-order, pseudo-second-order and intraparticle diffusion equations were selected to follow the adsorption process. Kinetic parameters such as rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated and discussed. It was indicated that the adsorption of copper(II) ions onto C. annuum seeds could be described by the pseudo-second-order kinetic model and also followed the intraparticle diffusion model up to 60 min, but diffusion is not only the rate controlling step. Thermodynamics parameters such as the change of free energy, enthalpy and entropy were also evaluated for the adsorption of copper(II) ions onto C. annuum seeds.

Synthesis and evaluation of demethoxyviridin derivatives as potential antimicrobials.

The in vitro antibacterial and antifungal activities of demethoxyviridin and some synthetic analogues were evaluated by the agar diffusion method. The minimum inhibitory concentrations (MIC) of the active compounds were also determined by the agar dilution method. Demethoxyviridin (1) showed moderate antibacterial activity against most of the strains tested. 1alpha-Hydroxydemethoxyviridin (3) showed antibacterial activity and the most potent in vitro antifungal activity with MIC of 20 microg/ml (0.062 mM) against Aspergillus niger, A. fumigatus, A. flavus, A. parasiticus, Fusarium solani, F. graminarum, Geotrichum candidum whereas 5'-methylfuro-(4',3',2'-4,5,6)androst-5-ene-3,17-dione (7) exhibited very weak antifungal activity against Candida albicans only.

Microbial transformations of isophorone by Alternaria alternata and Neurospora crassa.

Isophorone (3,5,5-trimethyl-2-cyclohexen-1-one), a monoterpene, and the structurally related 1,8-cineole and camphor, have demonstrated a protective effect against cancer, biological activity against a variety of microorganisms, and anti-oxidant properties. The derivatization of isophorone is, therefore, an important field of xenobiochemistry, pharmacology and toxicology. The aim of this study was to obtain derivatives of isophorone through microbial biotransformation and evaluate the biotransformation metabolites as potential antimicrobial agents. Incubation of isophorone with the fungi Alternaria alternata and Neurospora crassa afforded 4a-hydroxy- and 7-hydroxy-isophorone as transformation metabolites. The antimicrobial activities of isophorone and the metabolites were evaluated in vitro both by using agar dilution and microdilution methods. However, no significant antibacterial activity was observed when compared with those of standard substances.

Microbial hydroxylation of S-(-)-perillyl alcohol by Fusarium heterosporium.

S-(-)-Perillyl alcohol (p-mentha-1, 8-diene-7-ol) (1) (500 mg) was converted by Fusarium heterosporium ATCC 15625 over 10 days at 25 degrees C to a new metabolite, 1,2-dihydroxyperillyl alcohol (p-mentha-8-en-1,2,7-triol) (3) in a yield of 13% (70 mg). The structure of 3 was established by IR and NMR spectroscopic, specific rotation, and mass spectral studies.

Biotransformation of alpha-cedrol and caryophyllene oxide by the fungus Neurospora crassa.

Incubation of alpha-cedrol and caryophyllene oxide with Neurospora crassa afforded 12beta-hydroxy cedrol, 10alpha-hydroxy cedrol, and 3beta-hydroxy cedrol, and 12beta-hydroxy caryophyllene oxide as major metabolites, respectively. The antibacterial and radical scavenging activities of the metabolites were evaluated in vitro using broth microdilution and bioauthographic techniques. However, no significant antibacterial and antioxidant activities were observed when compared with those of standard substances.

Isotherm and kinetic studies of Burazol Blue ED dye biosorption by dried anaerobic sludge.

Biosorption potential of dried anaerobic sludge (DAS) for Burazol Blue ED (BB) was studied with respect to pH, equilibrium time, initial dye concentrations and temperature to determine equilibrium and kinetic models. The most suitable pH, equilibrium time and initial dye concentration were determined as 0.5+/-0.03, 75 min and 150 mg/L, respectively, at a biomass dosage of 0.4 g/L and 25 degrees C+/-1.0. The equilibrium data was best described by the Langmuir isotherm model. Maximum uptake capacity (q(m)) of DAS for the dyestuff (BB) were 118.3, 125.8 and 127.5mg/g biomass at temperatures of 25, 40 and 50 degrees C, respectively, indicating that the biosorption process is spontaneous and favored at higher temperatures. The overall biosorption process was best described by pseudo-second-order kinetic model. Gibbs free energy changes were calculated as -356.8, -519.7 and -520.6J/mol at 25, 40 and 50 degrees C, respectively.

Biotransformation of racemic diisophorone by Cephalosporium aphidicola and Neurospora crassa.

Racemic diisophorone (500 mg) was converted by Cephalosporium aphidicola and Neurospora crassa over 10 days at 25 degrees C to 8beta-hydroxydiisophorone in yields of 10% (52 mg) and 20% (103 mg), respectively. The structure was established by IR, specific rotation, mass spectral, 1D and 2D-NMR studies.