In a laboratory assay, it was shown that B. bassiana BCC48145, BCC2660, and P. lilacinum TBRC10638 were the three strains that exhibited the highest insecticidal activity against chili thrips, causing 92.5% and 91.86% and 92.3% corrected mortality, respectively. The fungi B. bassiana BCC48145 and P. lilacinum TBRC10638 were selected for greenhouse spraying. Cytotoxicity test of the extracts from both fungi evaluated against 4 animal cell lines: KB; human oral cavity carcinoma, MCF7; human breast adenocarcinoma, NCI-H187; human small cell lung carcinoma and GFP-expressing Vero cells, showed none-cytotoxic to all cell lines. An efficacy validation in the greenhouse showed that P. lilacinum TBRC 10638 was more effective than B. bassiana BCC48145 and could control the thrips up to 80% when using the fungus at 108 spores/mL. The LC50 values of P. lilacinum TBRC 10638 against chili thrips based on total thrips count from two experiments were 1.42 × 108 and 1.12 × 107 spores/mL when the fungal spores were sprayed once a week. The optimal concentration of P. lilacinum TBRC 10638 spores for effective control of chili thrips was determined at 1.41 × 109 spores/mL. The average efficacy of P. lilacinum TBRC 10638 for thrips control from 3 field trials was 30.08%, 14.39%, and 29.92%. This result was not significantly different from that of the chemical insecticide treatment group, which showed efficacy at 19.27%, 14.92%, and 19.97%. Furthermore, there was no difference in productivity among the different treatment groups. Our results demonstrated that P. lilacinum TBRC 10638 is a promising biocontrol agent that could be used as an alternative to chemical insecticide for controlling chili thrips.
Derivatives of the fungal depsidone, nidulin, have been synthesized in order to evaluate the potential of the chemical skeleton as antibacterial agents. Alkylation, acylation, and arylation reactions of nornidulin underwent in a regioselective manner to predominantly produce 8- O -substituted derivatives. Many of the semisynthetic derivatives showed more potent antibacterial activities than nidulin, In particular, 8- O -aryl ether derivatives displayed significant activities against Gram-positive bacteria, including Methicillin-resistant Staphylococcus aureus .
In a continuation of our research into antitubercular lanostane triterpenoids from submerged cultures of Ganoderma species, three strains, Ganoderma orbiforme BCC 22325, Ganoderma sp. BCC 60695, and Ganoderma australe BCC 22314, have been investigated. Fourteen new lanostane triterpenoids, together with 35 known compounds, were isolated. Antitubercular activities of these mycelium-associated Ganoderma lanostanoids against Mycobacterium tuberculosis H37Ra were evaluated. Taken together with the assay data of previously isolated compounds, structure-activity relationships of the antitubercular activity are proposed. Most importantly, 3β- and 15α-acetoxy groups were shown to be critical for antimycobacterial activity. The most potent compound was (24E)-3β,15α-diacetoxylanosta-7,9(11),24-trien-26-oic acid (35).
A polycyclic tetrahydroxanthone, actinomadurone, was isolated from the actinomycete Actinomadura sp. BCC 35430. Its structure was elucidated by extensive spectroscopic analyses. Actinomadurone showed antifungal activities against Curvularia lunata, Alternaria brassicicola, Colletotrichum capsici, and Colletotrichum gloeosporioides; and displayed cytotoxic activity against Vero cell lines. (C) 2017 Elsevier Ltd. All rights reserved.
The genus Hypoxylon, a member of the family Xylariaceae, has been known to produce significant secondary metabolites in terms of chemical diversity. Moreover, the compounds isolated can also be used as chemotaxonomic characters for differentiation among the two sections, which are sect. Annulata and sect. Hypoxylon. In our continuing chemical screening programme for novel compounds, the crude extracts of H. fendleri BCC32408 gave significant chemical profiles in HPLC analyses. Thus, the chemical investigation of these crude extracts was then carried out. The investigation led to the isolation of ten previously undescribed compounds including three terphenylquinones (fendleryls A - C), one terphenyl (fendleryl D), and six novel drimane - phthalide-type lactone/isoindolinones derivatives (fendlerinines A - F) along with seven known compounds (2-O-methylatromentin, rickenyl E, atromentin, rickenyls C - D, (+)-ramulosin, and O-hydroxyphenyl acetic acid). The chemical structures were determined on the basis of spectroscopic analyses, including 1 D, 2D NMR and high-resolution mass spectrometry, as well as chemical transformations. In addition, these isolated compounds were assessed for antimicrobial activity including antimalarial (against Plasmodium falciparum, K-1 strain), antifungal (against Candida albicans), antibacterial (against Bacillus cereus) activities. Cytotoxicity against both cancerous (KB, MCF-7, NCI-H187) and non-cancerous (Vero) cells of these compounds were also evaluated. (C) 2017 Elsevier Ltd. All rights reserved.
Nine alliacane sesquiterpenoids, inonoalliacanes A–I, were isolated from culture broth of the basidiomycete Inonotus sp. BCC 22670. The structures were elucidated on the basis of NMR spectroscopic and mass spectrometry data. The absolute configuration of inonoalliacane F was determined by application of the modified Mosher's method. Inonoalliacane A, the most abundant sesquiterpene constituent, exhibited moderate antibacterial activity against Bacillus cereus, whereas inonoalliacane B showed antiviral activity against herpes simplex virus type 1.
Hypocrellutins A-C (1-3), 2- and 4-pyridone alkaloids, were isolated from cultures of the scale-insect pathogenic fungus Hypocrella discoidea BCC 71382. The structures were elucidated on the basis of NMR spectroscopic and mass spectrometry data. The absolute configuration of hypocrellutin B (2) was determined by ECD calculation. Their plausibly biosynthetic pathways are proposed. All isolated compounds were inactive in the antifungal, antimalarial, antitubercular, and cytotoxic activity assays. (C) 2017 Elsevier Ltd. All rights reserved.
Twelve new compounds, including nine tropolones, nemanolones A−I (1–9), three 7-isochromenones, nemanecins A−C (10–12), and a new naturally isolated 4-isochromanone (13), along with two known compounds, 7,8-dihydroxy-3-methyl isochroman-4-one (XJP), and chaetoquadrin F, were isolated from culture broth of the fungus Nemania sp. BCC 30850. Structures of these compounds were elucidated by NMR and MS spectroscopic analyses. Nemanolones exhibited cytotoxic activities and two of them, compounds 1 and 2, also showed antibacterial activity against Bacillus cereus and antifungal activity against Candida albicans.
A new seco-tremulane, 11,12-epoxy-5,6-secotremula-1,6(13)-dien-5,12-olide (1), was isolated together with the known compounds, conocenolides A (2) and B (3), tremulenediol A (4), tremulenolide A (5), and two lanostane triterpenoids, trametenolic acid B (6), and pinicolic acid A (7), from cultures of the basidiomycete Flavodon flavus BCC 17421. Interconversion of conocenolides A/B was demonstrated. Compound 1 exhibited weak cytotoxic activities, whereas tremulenediol A showed antiplasmodial activity (IC50 8.6g/ml). Pinicolic acid A exhibited activity against herpes simplex virus type-1 (IC50 15g/ml) as well as cytotoxic activities.
Twelve 4-hydroxyquinoline derivatives (112) and three phenazine alkaloids (1315) 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 (16) and 4-hydroxyquinoline-N-oxides (811) exhibited antimalarial activity against Plasmodium falciparum, K1 strain (IC50 0.252.07μg/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.
Three new oxygen-bridged cyclooctadiene containing compounds, 5–7, phomoxydienes A–C, and two new dothiorelones I (8) and J (9), together with 10 known compounds were isolated from endophytic fungus, Phomopsis sp. BCC 45011. Structures were determined by NMR spectroscopic and MS spectrometric analyses. Mycoepoxydiene (1), deacetylmycoepoxydiene (2), phomoxydienes A (5) and C (7), and cytosporone E (12) displayed antimalarial and cytotoxic activities while 1893 A (3) and cytosporone P (13) showed only cytotoxic and antimalarial activity, respectively.
A new seco-tremulane (I) is isolated from cultures of the basidiomycete Flavodon flavus BCC 17421 together with six known compounds.
Two new hirsutane sesquiterpenes, marasmiellins A (1) and B (2), were isolated from cultures of the basidiomycete Marasmiellus sp. BCC 22389. The structures were elucidated on the basis of NMR spectroscopic and mass spectrometry data. The absolute configuration of marasmiellin B was determined by application of the modified Mosher's method.
Thirteen bioxanthracenes, including eight new 1–8, together with twelve oxanthracenes and analogues, including nine new 9–17, and two naturally occurring 18 and 19, were isolated from insect pathogenic fungus, Conoideocrella luteorostrata Zimm. BCC 31648. Structures were determined by NMR spectroscopic and MS spectrometric analyses. Compounds 14, 17, and 18 displayed antimalarial and cytotoxic activities while compounds 2, 9, 11, 12, 15 and 19 exhibited only cytotoxic activity.
Twelve aromadendrane sesquiterpenoids, inonotins A–L, and a previously unknown cyclofarnesane, i.e., inonofarnesane, together with two known compounds, were isolated from cultures of the wood-rotting basidiomycete Inonotus sp. BCC 23706. Inonotin I is identical to a previously reported compound with an incorrect structure. Structures of the compounds were elucidated by spectroscopic analysis and X-ray crystallography. The absolute configurations of inonotin D and inonofarnesane were determined by application of the modified Mosher’s method.
Four new compounds (1-4), which were (-)-(7R)-7-O-methylsydonic acid, gibellulic acid, gibellulins A and B, together with 14 known compounds (5-17 and orcinol) were isolated from the insect pathogenic fungus, Gibellula sp. BCC36964. The chemical structures were elucidated by employing NMR spectroscopic techniques, physico-chemical data, and chemical method. These compounds were evaluated for the biological activities including anti-bacterial, anti-phytopathogenic, anti-Herpes simplex virus-type 1 activities, and cytotoxicity against both cancerous (MCF-7, KB, NCI-H187) and non-cancerous (Vero) cells. (C) 2015 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.