SOLID PHASE MICROBIAL FERMENTATION OF ANABOLIC STEROID, DIHYDROTESTOSTERONE WITH ASCOMYCETE FUNGUS FUSARIUM OXYSPORUM

Objective: Microbial catalysis is used in the commercial production of many bioactive steroids. Solid phase microbial fermentation of anabolic steroid, dihydrotestosterone (DHT, 1), was carried out with ascomycete fungal strain Fusarium oxysporum (NRRL-1392).Methods: Sabouraud-4% glucose-agar was used to cultivate the fungal cultures as solid phase medium. Substrate 1 was incubated with Fusarium oxysporum (NRRL-1392) for 8 days. Microbial transformed metabolites were purified by using column chromatographic technique. Results: Ascomycete fungal strain Fusarium oxysporum (NRRL-1392), transformed dihydrotestosterone (1) to four oxidative metabolites 2-5  using solid phase microbial transformation metod. During biotransformation process the hydroxy group was incorporated in inactivated methine carbon atoms at C-7 and C-11 positions. Their structures were elucidated by means of a homo and heteronuclear 2D NMR and by HREI-MS techniques as 17b-hydroxyandrosta-1, 4-dien-3-one 2, androsta-1, 4-diene-3, 17-dione 3, 7a, 17b-dihydroxyandrosta-1, 4-dien-3-one (4), and 11a-hydroxyandrosta-1, 4-diene-3, 17-dione 5. The relative stereochemistry of newly incorporated hydroxy groups were deduced by 2D NOESY experiment.Conclusion: In conclusion, microbial biocatalysis is an attractive alternative tool for the preparation of new bioactive steroids, which might be difficult to prepare by conventional chemical routes. Furthermore, microbial-catalyzed biotransformations can produce commercially valuable steroidal pharmaceuticals for the pharmaceutical industry.Â

SOLID PHASE MICROBIAL REACTIONS OF SEX HORMONE, TRANS-ANDROSTERONE WITH FILAMENTOUS FUNGI

Objective: A microbial biotransformation study was performed on trans-androsterone (1) using solid phase medium. In the present context, trans-androsterone (1), a sex hormone was fermented with two filamentous fungi, Rhizopus stolonifer (black bread mold) and Fusarium lini.Methods: Sabouraud-4% glucose-agar were used to cultivate the fungal cultures as solid phase medium. Substrate 1 was incubated with R. stolonifer (ATCC 10404) and F. lini (NRRL 68751) for 8 days. Microbial transformed metabolites were purified by using column chromatographic technique. Results: The metabolism study of 1 revealed that various metabolites were detected when incubated with filamentous fungi. A total of 3 transformed products were obtained. The reactions occurred that exhibited diversity; including selective hydroxylation at C-6 and C-7 along with oxidation occurs at C-3 positions. Their structure and identified on the basis of extensive spectroscopic data (NMR, HREIMS, IR and UV) as 3b,7b-dihydroxy-5a-androstan-17-one 2 in a good yield (58%), 6b-hydroxy-5a-androstan-3,17-dione 3, and 3b,6b-dihydroxy-5a-androstan-17-one 4.Conclusion: Solid phase microbial transformation method can successfully be used for the development of new steroidal drugs. The modified steroidal molecules could favor when compared to their natural counterparts due to several medicinal advantages.Â

MICROBIAL OXIDATION OF FINASTERIDE WITH MACROPHOMINA PHASEOLINA(KUCC 730)

Objectives: New  microbial oxidative derivatives of Finasteride [17β-(N-tert-butylcarbamoyl)-4-aza-5α-androst-1-en-3-one] (1) has been investigated with Macrophomina phaseolina (ATCC730).Methods: Fermented media of  Macrophomina phaseolina (ATCC730) was prepared to cultivate the fungal cultures . Substrate 1 was incubated in liquid media for 16 days. After sixteen days, filtration and extraction of the fermented media was carried out with 9 L DCM in three portions. Resulting organic extract was dried using anhydrous (Na2SO4), and evaporated to afford a brown gum (950 mg). This on chromatographic purification with MeOH in CH2Cl2 afforded the metabolites 2-4 . Results: Three oxidised metabolites of finasteride (1) which were identified as 15-oxo-finasteride (2), 11a-hydroxyfinasteride (3), and 15β-hydroxyfinasteride (4). Metabolite 2 was found to be new. The structure of the oxidised metabolites were elucidated by 1-D (1H, 13C) and 2-D NMR (COSY, HMBC, HMQC, NOESY) techniques and MS analyses.Conclusion: As a result of these study, oxidation at C-7, C-11 and C-15 positions were found. Metabolite 2 was identified as a new metabolite

Synthesis, single crystal X-ray diffraction, Hirshfeld surface and biological activity of quinolone derivatives

Two new quinolone derivatives, 5-nitroquinolin-8-yl-3-bromobenzoate (1) and 5-nitroquinolin-8-yl-3-chlorobenzoate (2), were synthesized and their structures were elucidated using X-ray diffraction techniques. Both compounds crystallized in P21/n (monoclinic) space group having four independent molecules in asymmetric unit. The dihedral angle between benzene and planner quinoline rings in compounds 1 and 2 were found to be 117.7(2) and 117.4(2)ᵒ, respectively. No intermolecular hydrogen bonding was observed in compound 1. However, C-H···O intermolecular interaction was found to connect the molecules in crystal lattice of compound 2. Hirshfeld surfaces analysis was performed to evaluate the directions, and strength of interactions of molecules of compounds and 1 and 2 with neighbouring molecules, and the major contribution in the crystal packing was due to O-H (1, 24.6% and 2, 25.1%) interactions. The synthesized quinoline derivatives were found as potent anti-bacterial agents against E. coli reference (ATCC25922 and ATCC 35218) and multi-drug resistant strains (M2 and M3) with 91.42 to 94.72% inhibition. Both compounds 1 and 2 showed weak antileishmanial activity against L. Major promastigotes in vitro with IC50 values 73.2±3.1 and 72.2±2.3 mg/mL, respectively, and also found as cytotoxic in nature against 3T3 fibroblast cell line

Synthesis of antibacterial isocoumarins: Synthesis and antibacterial activity of 3-alkylisocoumarins and (dl)-3-alkyl-3,4-dihydroisocoumarins

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Cytotoxic, Antibacterial, and Leishmanicidal Activities of Paullinia pinnata (Linn.) Leaves

Background: Paullinia pinnata leaves are employed traditionally for the treatment of various ailments which are of biological origin. Objectives: The aim of this study was to explore cytotoxic, antibacterial, and antileishmanial properties of the leaves of Paullinia pinnata using in vitro models. Methods: Brine shrimp lethality bioassay was used to determine the cytotoxic activity of the methanol leaf extract of Paullinia pinnata. The activity of the extract against the growth of cultured Leishmania major (DESTO) promastigotes was used to investigate the leishmanicidal activities. The agar well diffusion method was used to investigate the antibacterial activity against Salmonella typhi, Pseudomonas aeruginosa, Shigella flexneri, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. Results: The methanol leaf extract of P. pinnata had no activity against Artemia salina (brine shrimp) and L. major. It showed a non-significant activity against E. coli and B. subtilis and no activity against P. aeruginosa, S. flexneri, S. typhi, and S. aureus. Conclusion: The methanol leaf extract of P. pinnata did not exhibit any cytotoxic and anti-leishmanial properties. Moreover, the activity against various species of bacteria was not significant

MICROBIAL METABOLISM OF AN ANTI-HIV AND ANTI-MALARIAL NATURAL PRODUCT ANDROGRAPHOLIDE

Objective: Andrographolide (1), the main crystalline bitter principle of Andrographis paniculata nees. (also known as rice bitter in the West Indies) was first isolated by Gorter, and characterized as trihydroxy lactone. It was also isolated from Holmskilodia sanguinea in very good yield. It possesses a wide range of biological activities, which is also important in the therapeutic fields including anti-inflammatory, anti-malarial, anti-viral, immuno-stimulant, anti-HIV, and cardiovascular properties. In the present study, we first time studied the microbial metabolism of andrographolide (1) with Cunninghamella elegans (TSY 0865) and Cephalosporium aphidicola (IMI-68689). Methods: Microbial cultures of the C. elegans and C. aphidicola were grown on Potato dextrose agar (PDA) at 25°C and stored at 4°C. Medium for C. aphidicola was prepared by mixing Glucose (50.0 g), KH2PO4 (1.0 g), MgSO4.7H2O (2.0 g), Glycin (2.0 g), KCl (1.0 g) and Gibberella trace element solution (2.0 mL) into distilled water (1 L) and maintained pH at 5.6. While C. elegans medium was prepared by adding Glucose (10.0 g), peptone (5.0 g), KH2PO4 (5.0 g), yeast extract (5.0 g), NaCl (5.0 g) and glycerol (10 mL) into distilled water (1 L) and maintained pH at 5.6. Results: Two compounds were obtained as transformed products. Based on physical and spectroscopic data, these have been identified as andropanolide (2) and 14-deoxy-11,12-didehydro andrographolide (3). Both compounds were previously obtained by the phytochemical investigation of A. paniculata and biotransformed product as well. Conclusion: It could be concluded that C. elegans and C. aphidicola were able to produce oxidative derivatives of 1 in a regio- and stereoselective manner. Present investigation has been conducted for the first time with C. elegans and C. aphidicola. Incubation of 1 for 9 days with fungal strains yielded isomerized and oxidative products 2 and 3. Structures of all metabolites were elucidated by using spectroscopic techniques

IMMUNOMODULATORY ACTIVITIES OF SOME COMMON LICHEN METABOLITES

Objective: To evaluate the immunomodulatory activities of some of the common lichen compounds by using chemiluminescence based cellular assays.Methods: Number of secondary lichen metabolites, representing a breadth of lichen substances, were investigated for their effects on the respiratory burst of human whole blood phagocytes, isolated human polymorphonuclear leukocytes (PMNs) and murine macrophages using luminol or lucigenin-based chemiluminescence probes. Results: This study identify a clear suppressive effect of some lichen metabolites on phagocytosis response upon activation with serum opsonized zymosan by several lichen substances. Amongst the compounds tested, orsellinic acid, methyl orsellinate, methyl haematomate, lecanoric acid and lobaric acid, showed a potent immunomodulatory activity as compared to the standards. The lobaric acid suppressed both the myloperoxidase dependent and myloperoxidase independent, Reactive Oxygen Species (ROS) production in the oxidative burst of polymorphonuclear neutrophils (PMN) at the lowest concentration tested (3.1 µg/ml). Whereas, lecanoric acid, suppressed only the myloperoxidase dependent ROS production with IC50< 3.1µg/ml when compared to the standard sodium diethyldithiocarbamate trihydrate (SDT) (IC50 = 1.3 ± 0.2 µg/ml). Orsellinic acid, methyl orsellinate and methyl haematomate showed a selective myloperoxidase independent pathway with IC50 values; < 3.1µg/ml; 6.1 ± 1.0 µg/ml;  3.3 ± 0.1 µg/ml, respectively, being lower as compared to standard SDT (IC50 = 8.2 ± 1.9 µg/ml). Conclusion: Based on the results obtained it is appropriate to conclude that lichen are not only a good source of antioxidants, but also potent immunomodulators, and thus deserve to be investigated further.Â

A facile three-step synthesis of (dl)-6,8 dedihydroxyagrimonolide

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In vitro antifungal, anti-inflammatory and cytotoxic activities of Rumex abyssinicus rhizome extract and bioassay-guided isolation of cytotoxic compounds from Rumex abyssinicus

  ABSTRACT. Rumex abyssinicus showed strong cytotoxicity against HeLa cells (IC50 = 22.25 μg/mL) and weak cytotoxicity against PC3 and BJ cells with percent inhibition of 58.6, 25.8 and 29.7% at 30.0 μg/mL. It showed moderate antifungal activity against Aspergillus niger with a percent growth inhibition of 55.5% at 3000 µg/mL. It also strongly inhibited oxidative burst with IC50 value of 24.8 μg/mL. DCM (100%) and DCM: EtOAc (1:1) fractions showed strong cytotoxicity against HeLa cells, whilst pet ether: DCM (1:1) fraction showed strong cytotoxicity against PC3 cells with IC50 values of 29.3, 26.3 and 24.3 μg/mL, respectively. Moreover, the DCM: EtOAc (1:1) fraction inhibited ROS production with IC50 value of 18.8 μg/mL. Cytotoxic fractions afforded chrysophanol (1), physicon (2), emodin (3), citreorosein (4) and β-sitosterol (5). Among the isolated compounds, emodin (3) showed strong cytotoxicity against HeLa cells, whilst chrysphanol (1) and physicon (2) showed strong cytotoxicity against PC3 cells with IC50 values of 8.94, 22.5, and 28.5 µM, respectively. In addition, emodin (3) and citreorosein (4) showed strong inhibition against ROS production with an IC50 value of 16.2 and 38.2 μg/mL. The findings of this study suggest R. abyssinicus as a good candidate for cancer and inflammation management.     KEY WORDS: Polygonaceae, Rumex abyssinicu Jacq., Cytotoxic, Antifungal, Anti-Inflammatory, Reactive oxygen species   Bull. Chem. Soc. Ethiop. 2022, 36(4), 879-892.                                                               DOI: https://dx.doi.org/10.4314/bcse.v36i4.13                                                     &nbsp