Bioactivity study and metabolic profiling of Colletotrichum alatae LCS1, an endophyte of club moss Lycopodium clavatum L.

Abstract

Endophytes are silent microbial partners of green plants that ensure hosts’ survival in odd conditions. They are known as the factories of multipotent metabolites with diverse bioactivities beneficial to modern pharmaceuticals industry. Endophytic fungi have been screened from a variety of plants and it is the first-time endophytes of club moss is being studied for production of antibacterial and antioxidative compounds. The present study reveals that Lycopodium clavatum L. harbors a potent niche of bioactive endophytic fungi and Colletotrichum alatae LCS1 was the prime producer of antibacterial and antioxidative compounds among them. The minimum inhibitory and bactericidal concentrations of ethyl- acetate culture extract ranged from 15.62 to 250 μg/mL against four Gram negative and three Gram positive microorganisms including methicillin resistant Staphylococcus aureus (ATCC-33591). Bio-autogram based screening followed by Gas chromatographic analysis confirmed the occurrence of 17 bioactive compounds and α-bisabolol is known to be the prime one. Alfa bisabolol is a unique and versatile bioactive essential oil and facilitates variety of functions. Killing kinetics data along with leakage of macromolecules into extracellular environment supports the cidal activity of the antibacterial principles at MBC values. Isolate C. alatae LCS1 was optimized by one variable at a time system coupled with response surface methodology for broad spectrum antibacterial production. The organism yielded maximum response (22.66±0.894 mm of zone of inhibition against MRSA) in 250 mL Erlenmeyer flask containing 50 mL potato dextrose broth supplemented with (g/L) glucose, 7.53; yeast extract concentration, 0.47; NaCl, 0.10 with medium pH 6.46; after 134 hours of incubation at 26°C. Optimized fermentation parameters enhanced antibacterial activity up-to more than 50% than the pre-optimized one (10.33±0.57 mm). Endophytic LCS1 was also efficient in free radical scavenging tested by DPPH, ABTS, H2O2 and FRAP assay with an IC50 values of 23.38±5.32 to 82.873±6.479 μg/mL.

Secondary metabolites of endophytic fungii isolated from the stem bark of Sungkai (Peronema canescens Jack.)

“…The extracts produced by them had strong antioxidant and antibacterial activity because they inhibited the four test bacteria. After the isolation of the compounds, they produced each compound, namely 3-hydroxy-4(hydroxy(4-hydroxyphenyl)methyl)-ɣ-butyrolactone (1) and 5-hydroxy-4-(hydroxymethyl)-2H-pyran-2-on (2), which have been found in previous studies [70,71]. These compounds belong to the phenolic and pyran group.…”

“…This compound have ever been found from Trichoderma sp isolated from root of brotowali (Tinaspora crispa). The proposed structure of compound 2 is compared with the same compound from the literature, namely compound 2* [70] shown in Table 5. The molecular structure of compound 2 which was equipped with the numbering of carbon atoms, the placement of the chemical shifts of protons and carbons, and the HMBC correlation is shown in Figure 8D, 8E, and 8F.…”

Antifungal activity of volatile and non-volatile metabolites of endophytes of Chloranthus elatior Sw.

“…Species of Penicillium, Aspergillus, Phoma, Phomopsis, Pestalotiopsis, Alternaria, Trichoderma, Colletotrichum, Chrysosporium, Nigrospora, Helicosporium, Exerohilum, and Fusarium are among the other isolates that produce spores or conidia. Different species of these fungal taxa are known to infect a variety of agricultural crops, and they have been randomly reported as endophytes as well (Chagas et al, 2013;Thanabalasingam et al, 2015;Suryanarayanan et al, 2018;Chatterjee et al, 2022;Santra and Banerjee, 2022a;Santra and Banerjee, 2022b;Santra et al, 2022). Metabolites of endophytic fungi Diaporthe sp., an isolate of Pinus densiflora, showed Santra and Banerjee 10.3389/fpls.2023.1156323 Frontiers in Plant Science frontiersin.org antibacterial, antidiabetic, and anticancer action, according to Saravanakumar et al (2021).…”

Endophytic fungi of Tradescantia pallida mediated targeting of Multi-Drug resistant human pathogens

“…The spore surface morphology and hyphae configuration were observed under a Scanning electron microscope. To study the morphology of test bacteria upon treatment with fungal crude extract, the samples were analyzed under SEM (EVO/18 Research, Carl Zeiss) ( Santra et al, 2022 ).…”