Marasmodrimanes A–R (1–18), eighteen previously undescribed drimane and 15-nordrimane sesquiterpenoids with diverse structures were isolated from cultures of basidiomycete Marasmius guyanensis TBRC-BCC 78466. Marasmodrimanes A (1) and B (2a/2b/2c) are highly oxygenated drimanes with a lactone bridge. Their structures were elucidated on the basis of spectroscopic analyses, X-ray crystallography, and a chemical correlation experiment. Marasmodrimanes F–J (6–10) are nitrogen atom-containing derivatives, while marasmodrimanes H–R (8–18) are B-ring aromatic 15-nor-drimanes.

Pleurocordyceps ophiocordycipiticola TBRC-BCC 9612, an entomopathogenic fungus collected from Khao Yai National Park, Thailand, was investigated for its secondary metabolites. Large-scale fermentation, followed by multistep chromatographic separation, resulted in the isolation of seven new compounds, including an ergot-type alkaloid (dihydroergopleurine, 2), three tetramic acid derivatives (pleurocordines A-C, 4-6), two acyclic terpenoids (7 and 8), and a dihydroisobenzofuran derivative (9), along with twelve known compounds. The structures of the new compounds were elucidated based on spectroscopic analyses, including 1D and 2D NMR, HRMS, and ECD data. Selected compounds were evaluated for antimalarial activity against Plasmodium falciparum K1, antibacterial activity against Bacillus cereus, Staphylococcus aureus, and Acinetobacter baumannii, antifungal activity against phytopathogens (Alternaria brassicicola and Colletotrichum acutatum), as well as cytotoxicity toward cancerous (MCF-7, NCI-H187) and non-cancerous (Vero) cells. Among them, ergot alkaloids dihydroergosine (1) and dihydroergopleurine (2) showed antimalarial and cytotoxic activities, while pleurocordine C (6) demonstrated antibacterial and weak cytotoxic effects. 14-Nor-epicoccarine A (3) and pleurocordine A (4) exhibited moderate antifungal activity, and the known akanthomycin showed broad-spectrum bioactivity but lacked selectivity between cancerous and normal cells. These findings expand the chemical diversity known from P. ophiocordycipiticola and highlight several compounds with promising biological profiles for further pharmacological study.

In the quest for novel compounds with potent activities against human infectious diseases from fungi in Thailand, cultures of the basidiomycete Panellus pusillus strain TBRC-BCC 43793 were chemically investigated. A new drimane sesquiterpenoid, 1β-hydroxypereniporin A (1), together with a known drimane, 6β-hydroxy-isodrimenin, was isolated using silica gel column chromatography and preparative High Performance Liquid Chromatography (HPLC). Its structure was elucidated on the basis of the spectroscopic method. The isolated compounds were inactive in the antiplasmodial, antimycobacterial, and antibacterial activity assays.

Six new polyketides (1–6) and two new naturally occurring compounds (7–8), along with seven known compounds, were isolated from the culture extracts of the entomopathogenic fungus Hypocrella luteola strain TBRC-BCC 76666.

Twelve hitherto undescribed cis-decalinoyltetramic acid derivatives (arengasetins A - L), a unique spiro[2.4]heptendione (spiroarengarone) and two benzoquinones (arengaquinones A and B), together with the highly oxygenated polycyclic molecule, epicolactone, were isolated from the palm fungus Leptosporella arengae TBRC-BCC 32590. Chemical structures were determined by extensive analyses of 2D NMR spectroscopic data and chemical means. The absolute configuration of arengasetin A (1) was confirmed by X-ray crystallographic information, while the absolute configurations of other related compounds were corroborated by comparison of NMR spectroscopic data and chemical reactions. The isolated compounds exhibited activity against Plasmodium falciparum (K1, multidrug-resistant strain, IC50 6.42 - > 38.76 μM), Bacillus cereus (MIC 0.78 - > 50.0 μg/mL), Staphylococcus aureus (MIC 1.56 - > 50.0 μg/mL), and Mycobacterium tuberculosis (MIC 6.25 - > 50.0 μg/mL). Cytotoxicity against both cancerous (MCF-7 and NCI-H187) and noncancerous (Vero) was also reported.

Two undescribed frenolicins H and I (1 and 2) along with six previously described frenolicin analogues [frenolicins A (3), B (4), UCF76-B (5), E - G (6 - 8)] and two anthraquinones [3,8-dihydroxy-1-propylanthraquinone-2-carboxylic acid (9) and 3,8-dihydroxy-1-propylanthraquinone (10)] were isolated from a longkong bark eating caterpillar-derived Streptomyces sp. TBRC17107. The chemical structures were determined by NMR spectroscopic information and HRESIMS data. Frenolicins H (1) and I (2) showed weak cytotoxicity against malignant and non-malignant cells. Frenolicins A (3) and B (4) showed antimalarial activity against Plasmodium falciparum (IC50 17.4 and 1.37 μM), antibacterial activity against Bacillus cereus and Staphylococcus aureus (MIC 50.0 and 0.20 μg/mL). Only frenolicin B had anti-plant pathogenic fungal activity against Collectotrichum acutatum and Alternaria brassicicola with MIC values of MIC 1.56 and 6.25 μg/mL, respectively. Frenolicins A and G possessed anti-Mycobacterium tuberculosis with equal MICs of 25.0 μg/mL.

Five undescribed ergostane triterpenoids, favolons D-G (1-4) and favolanone A (5), were isolated together with three known compounds, favolon (6), favolon C (7), and laschiatrion (8), from cultures of basidiomycete Favolaschia minutissima TBRC-BCC 19434. The undescribed compounds were evaluated for antimalarial, antitubercular, and antibacterial activities. Favolanone A (5) exhibited an IC50 value of 13 mu M in the antimalarial activity assay against Plasmodium falciparum K1 (multidrug-resistant strain). However, it also showed moderate cytotoxicity to Vero cells (IC50 22 mu M). In the present study, it was newly found that favolon (6) exhibits activity against the plant pathogenic fungus Alternaria brassicicola (MIC 3.13 mu g/ml).

Rice blast disease, caused by Pyricularia oryzae, is economically significant and reduces rice productivity. Chemical control methods have proven successful and are widely adopted for managing rice blast disease, but this practice is detrimental to the ecosystem and living creatures. Hence, research on environmentally friendly alternatives such as employing microorganisms to manage plant diseases has attracted significant attention. This study investigated the underlying mechanisms of Bacillus subtilis CH6 antagonistic activity against P. oryzae. The antagonistic activity of this strain was demonstrated by the dual culture assay, in which fungal growth was inhibited by 86.23%. The bacteria exhibited capacities to produce cell wall degradation enzymes, antifungal secondary metabolites, and volatile organic compounds (VOCs). Furthermore, strain CH6 displayed characteristics of plant growth-promoting bacteria including the ability to produce siderophores, indole-3-acetic acid (IAA) (3.27 +/- 0.04 mu g/ml), nitrogen fixation activity, as well as phosphate solubilizing activity. The evaluation of bacterial culture extracts indicated the presence of bioactive metabolites which exerted inhibitory activity against both fungal spore germination and mycelial growth, with MIC90 values of 0.375 and 60 mg/ml, respectively. Chemical analysis using ultra-high performance liquid chromatography- high resolution tandem mass spectrometry (UHPLC-MS/MS) confirmed the production of fengycins and surfactins which could be responsible for the antagonistic activity of B. subtilis CH6 against P. oryzae. This investigation provides new insights into the versatility of B. subtilis CH6 and its capability of controlling P. oryzae as a promising candidate for the development of dual-functioned biocontrol products.

Fourteen new cytochalasans, brunnesins A–N (1–14), along with eleven known compounds, were isolated from the culture extracts of the insect pathogenic fungus Metarhizium brunneum strain TBRC-BCC 79240.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A chemical investigation on broth and mycelia extracts of the endophytic fungus Curvularia lunata BCC76963 led to the isolation of five new eremophilane sesquiterpenoids, curvuleremophilanes A-D (1 -4) and septeremophilane I (5), one new conjugated unsaturated fatty acid, (6S,2E,4E)-8-hydroxy-4,6dimethylocta-2,4-dienoic acid (6), and one new phenylacetic acid derivative, 4'-chlorocurvulin (8), along with ten known compounds. The chemical structures were elucidated based on the analyses of HRESIMS and NMR spectroscopic data. The absolute configurations of eremophilanes were assigned by the evidence from NOESY correlations, chemical conversion, optical rotation values, and ECD spectroscopic data in conjunction with biogenetic considerations. In addition, the absolute stereochemistry of compound 5 was confirmed by X-ray crystallography. Curvuleremophilane A (1), dendryphiellin I (10), chaetopenoid B (11), and bipolaroxin (12) displayed antimalarial activity against Plasmodium falciparum K1 with IC50 values in a range of 3.64-7.77 mu M and antibacterial activity against Bacillus cereus and Staphylococcus aureus with MIC values in a range of 3.13-12.50 and 1.56-25.00 mu g/mL, respectively. These compounds, except for compound 11, also showed cytotoxicity against NCI-H187 and Vero cells with respective IC50 values in a range of 2.76-3.97 and 2.34-4.67 mu M. (c) 2023 Published by Elsevier Ltd.

Seven previously undescribed compounds including five tanzawaic acid analogues [named 10-hydroxytanzawaic acid U (1), 10-hydroxytanzawaic acid Q (2), 10-hydroxytanzawaic acid T (8), tanzawaic acids Z1 (9) and Z2 (11)], 7-methoxy-2,5-dimethyl-2,3-dihydrobenzofuran-6-ol (15), and (1S,3R)1,8-dimethoxy-3,5-dimethyl-6-hydroxy isochroman (17) along with fifteen known compounds were isolated from the endophytic fungus, Penicillium citrinum BCC71086. The absolute stereochemistry of tanzawaic acid derivatives were verified by modified Mosher's method together with NOESY spectral information. The isolated compounds were evaluated for antimicrobial activity as well as cytotoxicity against both cancerous (MCF-7 and NCI-H187) and non-cancerous (Vero) cells. Tanzawaic acids possessed broad spectrum of antimicrobial activity without significant cytotoxicity. In addition, among these isolated compounds, the unknown dihydrobenzofuran 15 had the strongest antimalarial activity with IC50 value of 3.76 mu M. All tested compounds also possessed antitubercular activity with MIC values in a range of 6.25-25.0 mu g/mL. (C) 2022 Elsevier Ltd. All rights reserved.

Three undescribed abyssomicin derivatives, including microbimisin, abyssomicins Z1, and Z2, were isolated from the soil actinomycete Microbispora rhizosphaerae sp. nov. TBRC6028. Chemical structures were determined by NMR spectroscopic data (1H, 13C, COSY, HSQC, HMBC, and NOESY spectra) and the absolute configurations were verified by single-crystal X-ray diffraction analyses together with the ECD spectral data. Microbimisin and abyssomicin Z1 exhibited weak antibacterial activity against Bacillus cereus with MIC values of 25.0 and 50.0 μg/mL without cytotoxicity against MCF-7 and Vero cells at the concentration of 50 μg/mL.

Eight previously undescribed naturally-occurring compounds, including abyssomycins Y - Z, methyl aeruginoate, desferri-ferrithocin-4-hydroxyphenethylester, streptomethiocins A - B, furaquinocin I, and streptolactone, along with eleven known compounds were isolated from the endophytic Streptomyces sp. TBRC7642. The chemical structures were determined based on spectroscopic means including 1D, 2D NMR spectroscopy and mass spectrometry. The absolute configurations were assigned by relying on CD spectra and their optical rotations. In addition, the isolated compounds were evaluated for biological activity, such as antimalarial, antitubercular, antibacterial (both Gram-positive and Gram-negative bacteria), as well as for cytotoxicity against MCF-7, NCI-H187, and Vero cells.

Five new compounds, iranginins A-E (1-5), together with sixteen known compounds were isolated from the insect pathogenic fungus Ophiocordyceps irangiensis BCC 2728. The structures and the absolute configurations of the new compounds were established by spectroscopic analyses, the application of modified Mosher's method (for 2), ECD calculation (for 5), and X-ray crystallographic analysis (for 4). LL-Z1640-5 and mucorisocoumarin C were active against Mycobacterium tuberculosis (MIC 41.7 and 85.0 mu M, respectively), while peyroisocoumarin D exhibited cytotoxic activity (IC50 65.6 mu M).

Eight new anthrone derivatives, which are (+)-oxanthromicins E (1), F (4), and G (5), (+/-)-hemi-oxanthromicin D (2), azanthromicin A (7), adxanthromicin A(2) (10), 3-methoxy oxanthromicin (11), and (+/-)-oxanthromicin G (13), along with eight previously described compounds (6, 8, 9, 12, 14-17) have been isolated from the terrestrial actinomycete, Actinomodura sp. BCC47066. The chemical structures have been determined on the basis of NMR spectroscopic information and chemical degradation. The configurations were assigned based upon CD spectral analyses, compared with the related compounds. Furthermore, the isolated compounds were assessed for biological activity. Compounds 10, 12, and 16 showed anti-Bacillus cereus with IC50 in a range of 1.56-12.50 mu g/mL, while compounds 10 and 12 exhibited anti-phytopathogenic activity against Colletotrichum capsici and C. gloeosporioides with equal IC50 value of 6.25 mu g/mL. All tested compounds possessed low cytotoxicity against both malignant and non-malignant cells.

Twelve 4-hydroxyquinoline derivatives (1⿿12) and three phenazine alkaloids (13⿿15) have been isolated from Pseudomonas aeruginosa BCC76810. All these compounds, except compounds 6, 7, 9, and 11, are known. The new quinolines are 2-((Z)-undec-4⿲-enyl)-4-hydroxyquinoline (6), 2-(3⿲-(2⿲-hexylcyclopropyl)propyl)-4-hydroxyquinoline (7), 2-n-octyl-4-hydroxyquinoline N-oxide (9), and 2-((Z)-undec-4⿲-enyl)-4-hydroxyquinoline N-oxide (11). Their structures were elucidated based on the spectroscopic information, such as 1D, 2D NMR, UV, and HRESIMS data. 4-Hydroxyquinolines (1⿿6) and 4-hydroxyquinoline-N-oxides (8⿿11) exhibited antimalarial activity against Plasmodium falciparum, K1 strain (IC50 0.25⿿2.07μg/mL) with moderate to weak cytotoxicity against cancerous (KB, MCF-7, NCI-H187) and non-cancerous (Vero) cells. In addition, 4-hydroxyquinoline N-oxides also displayed anti-Bacillus cereus and antioxidant activities.

Three polycyclic tetrahydroxanthones, chrestoxanthones A−C, together with known albofungin and chloroalbofungin were isolated from the actinomycete Streptomyces chrestomyceticus BCC 24770. Their structures were elucidated by extensive spectroscopic analyses. Chrestoxanthone A was active against Curvularia lunata and Alternaria brassicicola, while all other isolated metabolites displayed broad antifungal activities against C. lunata, A. brassicicola, Colletotrichum capsici, and Colletotrichum gloeosporioides.

Severe chili anthracnose disease in Thailand is caused by Colletotrichum gloeosporioides and C. capsici. To discover anti-anthracnose substances we developed an efficient dual-fluorescent labeling bioassay based on a microdilution approach. Indicator strains used in the assay were constructed by integrating synthetic green fluorescent protein (sGFP) and Discosoma sp. red fluorescent protein (DsRedExp) genes into the genomes of C. gloeosporioides or C. capsici respectively. Survival of co-spore cultures in the presence of inhibitors was determined by the expression levels of these fluorescent proteins. This developed assay has high potential for utilization in the investigation of selective inhibition activity to either one of the pathogens as well as the broad-range inhibitory effect against both pathogens. The value of using the dual-fluorescent assay is rapid, reliable, and consistent identification of anti-anthracnose agents. Most of all, the assay enables the identification of specific inhibitors under the co-cultivation condition.