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The genus Phoma has been explored for a wide range of secondary metabolites signifying a huge range of bioactivities. Phoma sensu lato is a major group that secretes several secondary metabolites. The genus Phoma mainly includes Phoma macrostoma, P. multirostrata, P. exigua, P. herbarum, P. betae, P. bellidis, P. medicaginis, P. tropica, and many more species from the genus that are continuously being identified for their potential secondary metabolites. The metabolite spectrum includes bioactive compounds like phomenon, phomin, phomodione, cytochalasins, cercosporamide, phomazines, and phomapyrone reported from various Phoma spp. These secondary metabolites show a broad range of activities including antimicrobial, antiviral, antinematode, and anticancer. The present review is aimed to emphasize the importance of Phoma sensu lato fungi, as a natural source of biologically active secondary metabolites, and their cytotoxic activities. So far, cytotoxic activities of Phoma spp. have not been reviewed; hence, this review will be novel and useful for the readers to develop Phoma-derived anticancer agents. Key points: • Different Phoma spp. contain a wide variety of bioactive metabolites. • These Phoma spp. also secrete cytotoxic and antitumor compounds. • The secondary metabolites can be used for the development of anticancer agents. [ABSTRACT FROM AUTHOR]

Fungal endophytes are considered one of the most important reservoirs of bioactive compounds which defeat resistant microbes. In our study, endophytic Alternaria alternata was isolated from Ziziphus spina-christi and identified morphologically and genetically with accession number OM 331,682. Preliminary phytochemical screening of ethyl acetate (EA) crude extract of A. alternata revealed that this extract contains alkaloids, tannins, flavonoids, glycosides, phenols, and terpenoids. Moreover, the extract was analyzed using gas chromatography-mass spectrometry (GC–MS) which verified the presence of numerous bioactive compounds. Antimicrobial results illustrated that EA crude extract exhibited promising antimicrobial activity against Gram-negative bacteria (Escherichia coli ATCC 11229, Proteus vulgaris RCMB 004, Pseudomonas aeruginosa ATCC 27853, and Klebsiella pneumonia RCMB 003), Gram-positive bacteria (Bacillus subtilis RCMB 015, Staphylococcus aureus ATCC 25923, and Staphylococcus epidermidis ATCC 14990), and unicellular fungi (Candida albicans ATCC 90028). Ultrastructure study of treated K. pneumonia showed remarkably elucidated destruction of the cell wall and cell membrane and leakage of cytoplasmic materials. Furthermore, the extract has potential antioxidant activity where IC50 was 409 µg/mL. Moreover, this extract did not show any toxicity on Vero normal cell line. These findings confirmed that the endophytic A. alternata from Z. spina-christi is a promising source of bioactive compounds which can be used in different biological applications. [ABSTRACT FROM AUTHOR]

Purpose: An endangered Tsuga chinensis (Franch.) Pritz. is widely used as a natural medicinal herb in many countries, but little has been reported on its culturable endophytic fungi capable of producing secondary metabolites applied in modern medicine and pharmacy. The present study aimed to evaluate the distribution of fungal endophytes and their cytotoxic and antioxidant properties. Methods: This study used the surface sterilization method to isolate endophytic fungi which were then identified using morphological characteristics and ITS sequence analysis. The antimicrobial and cytotoxic potentials of fungal ethyl acetate extracts were evaluated by the minimum inhibitory concentration (MIC) and sulforhodamine B (SRB) assays, respectively. Paclitaxel-producing fungi were primarily screened using PCR-based molecular markers. Additionally, biochemical assays were used to reveal the antioxidant potencies of selected strains. Results: A total of sixteen endophytic fungi that belonged to 7 known and 1 unknown genera were isolated from T. chinensis. The greatest number of endophytes was found in leaves (50%), followed by stems (31.3%) and roots (18.7%). Out of 16 fungal strains, 33.3% of fungal extracts showed significant antimicrobial activities against at least 4 pathogens with inhibition zones ranging from 11.0 ± 0.4 to 25.8 ± 0.6 mm. The most prominent cytotoxicity against A549 and MCF7 cell lines (IC50 value < 92.4 μg/mL) was observed in Penicillium sp. SDF4, Penicillium sp. SDF5, Aspergillus sp. SDF8, and Aspergillus sp. SDF17. Out of three key genes (dbat, bapt, ts) involved in paclitaxel biosynthesis, strains SDF4, SDF8, and SDF17 gave one or two positive hits, holding the potential for producing the billion-dollar anticancer drug paclitaxel. Furthermore, four bioactive strains also displayed remarkable and wide-range antioxidant activity against DPPH, hydroxyl radical, and superoxide anion, which was in relation to the high content of flavonoids and polyphenols detected. Conclusion: The present study exploited for the first time fungal endophytes from T. chinensis as a promising source for the discovery of new bioactive compounds or leads for the new drug candidates. [ABSTRACT FROM AUTHOR]

A new yellow pigment trypethelonamide A (1), and a new dark violet-red pigment 5′-hydroxytrypethelone (2), as well as three known dark violet-red pigments (+)-8-hydroxy-7-methoxytrypethelone (3), (+)-trypethelone (4) and (-)-trypethelone (5) were isolated from the cultured lichenized fungus Trypethelium eluteriae. The structures of 1 and 2 were determined to be 1, 2-naphthoquinone derivatives by extensive spectroscopic analysis. The absolute configurations of 1 and 2 were assigned by quantum electronic circular dichroism (ECD) calculation. All isolated compounds were evaluated for cytotoxicities against A549, HepG2 and RKO cell lines, and antioxidant effects on DPPH. Compounds 1–5 showed moderate and weak cytotoxicities against RKO cell line with IC50 from 22.6 to 113.5 μM. [ABSTRACT FROM AUTHOR]