The crystal structure and unambiguous absolute configuration of meleagrin (1) isolated from fungus Emericella dentata Nq45 is reported herein to first time on the bases of single crystal X-ray diffraction. Together with 1, haenamindole (2), isorugulosuvine (3), secalonic acid D (4), ergosterol (5) and cerebroside A (6) were obtained and their structures were determined by ESI MS and NMR data analysis. Diverse biological activity of meleagrin (1) was investigated. Compound 1 pronounced potent cytotoxicity against the human cervix carcinoma cell line KB-3-1 and

Terretonin O (1), a new meroterpenoid, was isolated individually from both methanolic extracts of thermophilic Aspergillus terreus TM8 and marine Aspergillus terreus LGO13. The recently reported terretonins M (2) and N (3) were further isolated from the fungus LGO13 along with nine known compounds, terrelumamide A (4), terrein (5), methyl-3,4,5-trimethoxyl-2-[2-(nicotinamide)benzamido]benzoate (6), butyrolactones I-III (7-9), aspulvinone O (10), ergosterol, ergost-4-ene-3-one and methyl linoleate. Structure of terretonin O (1) was established on the bases of HRESIMS, 1D and 2D NMR spectra and comparison with its analogues in literatures. The relative stereochemistry of 1 was assigned on the basis of NOESY spectra and comparison with reported configuration of its congener compounds 2 and 3. The antimicrobial and cytotoxic activities of the fungal extracts and obtained compounds were assayed using a set of microorganisms, and cervix carcinoma cell line (KB-3-1), respectively. Isolation and taxonomical characterization of the producing strains are reported.

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Background Calothamnus quadrifidus R.Br has many traditional uses and there are few reports about its chemical and biological activities. So our aim is to isolate the triterpenoidal compounds from dichloromethane fraction (DCMF) of Calothamnus quadrifidus R.Br leaves and in addition to evaluate the antibacterial activity of the isolated compounds. Methods DCMF of C. quadrifidus leaves was subjected to different chromatographic techniques to isolate pure triterpenoidal compounds which were identified using different chemical and spectroscopic techniques. Antibacterial activities of the isolated compounds were evaluated using agar well diffusion method while minimum inhibitory concentration was assessed by microtiter plate assay method. Results Five compounds were isolated and they were betulinic acid (1), ursolic acid (2), 3-acetyl-23-hydroxy betulinic acid (3), 2,23-dihydroxy betulinic acid (4) and 2,21,23-trihydroxy betulinic acid (5) were isolated from DCMF of C. quadrifidus leaves for the first time. Compounds 4 and 5 showed strong antibacterial activity against S. typhimurium while compound 4, 5 and 3, 4 exhibits moderate effect against E.coli and S. aureus respectively. Conclusion Pure triterpenoidal compounds isolated from C. quadrifidus leaves showed antibacterial activities in different strengths.

Two new compounds calothphenone (1) and 6-methoxy kaempferol 3-O-(6``-E-p-coumaroyl)-β-Dglucopyranoside (6-methoxy tiliroside) (2) along with six known compounds viz gallic acid (3), methyl gallate (4), kaempferol 3-O-(6``-E-p-coumaroyl)-β-D-glucopyranoside (tiliroside) (5), castalagin (6), kaempferol (7) and quercetin (8) were isolated from the ethyl acetate fraction (EAF) of 80 % aqueous methanol extract of C. quadrifidus aerial parts. Their structure was established based on different chemical and spectroscopic techniques ( 1 H/ 13 C NMR and 2D NMR). Antioxidant activity for EAF and compounds 1, 2 and 5 was evaluated using DPPH, superoxide radical and nitric oxide (NO) inhibition methods. EAF exhibited strong activity to inhibit DPPH, superoxide and NO radicals. Moreover, all tested compounds demonstrated a close high ability to inhibit superoxide and NO radicals in comparison to ascorbic acid, but they exerted lower activity towards DPPH radical.