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Chemical investigations of the termite-associated Streptomyces tanashiensis BYF-112 resulted in the discovery of four novel alkaloid derivatives: vegfrecines A and B (1 and 2), exfoliazone A (3), and venezueline H (7), in addition to nine known metabolites (4 − 6 , 8 − 13). The structures of these compounds were elucidated through comprehensive spectroscopic analysis and comparison with existing literature data. Antibacterial assays revealed that viridomycin A (11) exhibited potent antibacterial activity against Staphylococcus aureus , with a zone of inhibition (ZOI) of 12.67 mm, in comparison to a ZOI of 17.67 mm for the positive control gentamicin sulfate. Viridomycin A (11) showed moderate activity against Micrococcus tetragenus and Pseudomonas syringae pv. actinidae , with ZOI values of 15.50 and 14.33 mm, respectively, which were inferior to those of gentamicin sulfate (34.67 and 24.00 mm). Viridomycin F (12) also exhibited moderate antibacterial effects against S. aureus , M. tetragenus , and P. syringae pv. actinidae , with ZOI values of 8.33, 16.50, and 10.83 mm, respectively. Cytotoxicity assays demonstrated that viridobruunine A (5), exfoliazone (6), viridomycin A (11), and X-14881E (13) exhibited significant cytotoxicity against human malignant melanoma (A375), ovarian cancer (SKOV-3), and gastric cancer (MGC-803) cell lines, with IC 50 values ranging from 4.61 to 19.28 μmol·L−1. Furthermore, bioinformatic analysis of the complete genome of S. tanashiensis suggested a putative biosynthetic gene cluster (BGC) responsible for the production of compounds 1−12. These findings indicate that the secondary metabolites of insect-associated S. tanashiensis BYF-112 hold promise as potential sources of novel antibacterial and anticancer agents. [ABSTRACT FROM AUTHOR]

BACKGROUND: Wheat powdery mildew, caused by the biotrophic pathogen Blumeria graminis f. sp. tritici (Bgt) is a serious fungal disease. Natural metabolites produced by microorganisms are beneficial biological control agents to inhibit Bgt. In the present study, we investigated the effects of Aspergillus chevalieri BYST01 on wheat powdery mildew. RESULTS: A strain isolated from the termite was identified as A. chevalieri BYST01 by morphological characteristics and phylogenetic analysis. The fermentation broth of BYST01 showed good biocontrol effect on the Bgt in vivo with the control efficiencies of 81.59% and 71.34% under the protective and therapeutic tests, respectively. Four known metabolites, including the main compound physcion (30 mg/L), were isolated from the fermentation broth of BYST01 extracted with ethyl acetate. Importantly, under a concentration of 0.1 mM, physcion repressed conidial germination of Bgt with an inhibition rate of 77.04% in vitro and showed important control efficiencies of 80.36% and 74.64% in vivo under the protective and therapeutic tests, respectively. Hence, the BYST01 showed important potential as a microbial cell factory for the high yield of the green natural fungicide physcion. Finally, the biosynthetic gene clusters responsible for physicon production in BYST01 was predicted by analyzing a chromosome‐scale genome obtained using a combination of Illumina, PacBio, and Hi‐C sequencing technologies. CONCLUSION: Aspergillus chevalieri BYST01 and its main metabolite physcion had a significant control effect on wheat powdery mildew. The biosynthesis pathway of physcion in BYST01 was predicted. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A Bacillus siamensis YC‐9 strain was isolated from termite nest. The strain was used to produce several important industrial enzymes by utilizing different agricultural by‐products with solid‐state fermentation (SSF). It was observed that most of the substrates that were studied were strongly positively affected by alkaline treatment for the production of enzymes. The highest yields for protease, α‐amylase, and cellulase were 82.87, 42.81, and 1.54 IU g−1, achieved on alkaline‐treated corn pericarp, rice bran, and wheat bran respectively. However, untreated soybean meal was the best choice for the secretion of pectinases (66.65 IU g−1). In general, ultrasonic pretreatment was more effective than microwave treatment and it promoted the production of proteases on soybean meal, sunflower meal, and wheat bran. The findings of the present study will provide some theoretical basis for enzyme production in the future. © 2021 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

The present study investigated the chemical compositions and antimicrobial activities of essential oil from Pterocarya stenoptera. The essential oil obtained by hydrodistillation from the dried leaves of P. stenoptera was analysed by GC–MS and 39 constituents accounting for the total 90.44% of the oil were identified. The main constituents were δ-cadinene (24.83%), caryophyllene oxide (9.10%), α-cadinol (7.48%) and β-elemene (6.24%). The antimicrobial activity of the oil was evaluated by disc diffusion and broth microdilution methods. The essential oil was found to show broad-spectrum antimicrobial activities against all the tested microorganisms. Bacillus subtilis was the most sensitive strain with the minimum inhibitory concentration of 0.23 mg/mL. The results suggested that the essential oil was a potential source of natural antimicrobials in food preservation and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

Background: Previously, eight new alkaloids were obtained from the fermentation extract of termite-associated Streptomyces tanashiensis BYF-112. However, genome analysis indicated the presence of many undiscovered secondary metabolites in S. tanashiensis BYF-112., Results: Herein, 12 new alkaloids, tianwuine A-E (1-5), cephalandole C (6), venezuelines I-L (7-10), N-(4-methylphenyl-2-hydroxy) formamide (11) and N-(5-formyl-2-hydroxyphenyl) formamide (12), as well as three known metabolites (13-15) were discovered from BYF-112 based on a combination of genome mining and the one strain many compounds (OSMAC) strategy. Plausible biosynthetic pathways of 1-13 were proposed using bioinformatic analysis of the full genome of BYF-112. Partial metabolites were evaluated in vitro for their antibacterial, phytotoxic, and anti-inflammatory activities. Pyrroloformamide A (14) showed strong antibacterial activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas syringae pv. actinidae, Xanthomonas oryzae pv. oryzae and Xanthomonas oryzae pv. oryzicola at a concentration of 50 μg per 6 mm disk. Simultaneously, pyrroloformamide A (14) also had a strong inhibitory effect on the radicle growth of Echinochloa crusgalli with an inhibition rate of 98.01% at a concentration of 100 μg/mL, equivalent to the positive 2,4-dichlorophenoxyacetic acid. Subsequently, the possible herbicidal mechanism of 14 was explored using molecular docking simulation. In addition, venezueline G (13) displayed a strong inhibitory effect of NO production, with an half-maximal inhibitory concentration (IC 50 ) value of 2.3 μm, which was comparable with that of BAY 11-7082 with an IC 50 value of 2.1 μm., Conclusion: These findings revealed a perspective for the development of novel bioactive drugs in the food, agricultural, and biomedical fields utilizing the metabolites of BYF-112. © 2025 Society of Chemical Industry., (© 2025 Society of Chemical Industry.)

Background: Wheat powdery mildew, caused by the biotrophic pathogen Blumeria graminis f. sp. tritici (Bgt) is a serious fungal disease. Natural metabolites produced by microorganisms are beneficial biological control agents to inhibit Bgt. In the present study, we investigated the effects of Aspergillus chevalieri BYST01 on wheat powdery mildew., Results: A strain isolated from the termite was identified as A. chevalieri BYST01 by morphological characteristics and phylogenetic analysis. The fermentation broth of BYST01 showed good biocontrol effect on the Bgt in vivo with the control efficiencies of 81.59% and 71.34% under the protective and therapeutic tests, respectively. Four known metabolites, including the main compound physcion (30 mg/L), were isolated from the fermentation broth of BYST01 extracted with ethyl acetate. Importantly, under a concentration of 0.1 mM, physcion repressed conidial germination of Bgt with an inhibition rate of 77.04% in vitro and showed important control efficiencies of 80.36% and 74.64% in vivo under the protective and therapeutic tests, respectively. Hence, the BYST01 showed important potential as a microbial cell factory for the high yield of the green natural fungicide physcion. Finally, the biosynthetic gene clusters responsible for physicon production in BYST01 was predicted by analyzing a chromosome-scale genome obtained using a combination of Illumina, PacBio, and Hi-C sequencing technologies., Conclusion: Aspergillus chevalieri BYST01 and its main metabolite physcion had a significant control effect on wheat powdery mildew. The biosynthesis pathway of physcion in BYST01 was predicted. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Mahonia fortunei belongs to Berberidaceae, and is often used as a potted plant in Chinese tradition medicine (Li et al. 2015). In March 2019, leaf blight was observed on this species in the campus of Anhui Agricultural University (31°51'51″N; 117°15'31″E) in Hefei City, Anhui Province, China. The average disease incidence was 35% over 20 m2 planting area. Symptoms of the disease are easily apparent, with irregular, dark brown necrosis at the edge of the leaves. To identify the pathogen, symptomatic leaves were collected from three symptomatic leaves from three plants and cut into small pieces. Leaf pieces from the margin of the diseased tissues were surface sterilized for 1 min in 75% ethanol, rinsed three times with sterile distilled water, and subsequently, plated onto potato dextrose agar (PDA) and incubated in dark at 28°C for 4 days. The colonies of three isolates were obtained and appeared morphologically similar in agar media. The cultures were initially white, gradually becoming dark gray, and could grow to the edges of plates (90mm diameter) four days after subculturing. After 7 days on media, the colony was induced for sporulation by UV for 15min, and conidia were observed after 2 weeks. Conidia were nonseptate, hyaline, and oval, measuring 16.9 to 25.3 μm (mean 21.4 μm) × 5.0 to 8.4 μm (mean 6.8 μm) (n = 50). The isolate was identified as Botryosphaeria dothidea preliminarily according to the morphological characteristics (Zhai et al. 2014). For accurate identification, DNA was extracted from the mycelia. The internal transcribed spacer (ITS), β-tubulin (TUB) and Ef1-a were amplified and sequenced using primers ITS1/ITS4, Bt2a/Bt2b and 983f /2228r, respectively (Zhai et al. 2014). The 543-bp ITS (GenBank accession no. MK850215), 673-bp TUB (no. MN370930) and 1069-bp Ef1-a (no. MN598070) showed >99% identity with those of B. dothidea KP183180 (Xu et al. 2015), KU306116 (Lisboa et al. 2016) and DQ767637.1 (Schoch et al. 2006), respectively. Based on cultural characteristics and phylogenetic analysis, the current isolate associated with leaf blight of M. fortunei was identified as B. dothidea. The representative strain was deposited at the China Center for Type Culture Collection (CCTCC) as CCTCC AF 2019004 SX03. Pathogenicity test was performed on three healthy M. fortunei on campus. Three branches of each plant were selected and all leaves on branches were wounded with dissecting needle by puncturing, then inoculated with a spore suspension (105 conidia/mL) by a hand-held spray bottle, using sterile water as control (Huang et al. 2019). In order to maintain high relative humidity, the inoculated leaves were sealed with transparent plastic bags for 3 days. Fourteen days after inoculation, symptoms (leaf blight) were similar to those on infected leaves on campus, while the controls remained healthy. The experiments were conducted three times and the pathogen was reisolated from inoculated leaves and was confirmed as B. dothidea based on morphological and molecular analyses. To our knowledge, this is the first report of B. dothidea causing marginal leaf necrosis on M. fortunei in China. This study provides a preliminary basis for identifying the causal agent of this plant disease.

Ligustrum japonicum is a small evergreen tree belonging to the Oleaceae and widely grown in China as a landscape ornamental and medicinal plant (Oh et al. 2021). In April 2021, a leaf spot disease was observed on Ligustrum japonicum in the campus of Anhui Agricultural University (31°51'4″N; 117°14'54″E), in Hefei City, Anhui Province, China. Approximately 50% of L. japonicum infections showed symptoms of round to oval, brown to dark brown lesions surrounded by a yellow halo. Diseased leaves were collected to determine the caused pathogen. Nine tissue pieces from three symptomatic leaves were surface sterilized with 2% NaClO for 1-2 minutes, followed by 75% ethanol for 1 minute, and then rinsed with sterile water for three times. The tissues samples were plated on potato dextrose agar（PDA）medium and incubated at 28 °C for 3 days. Seven fungal isolates were obtained from the plated tissues; the fungal hyphae were initially white and finally gray brown with flocculent aerial mycelia. Conidia were solitary or in chains, with various shapes, mostly subglobose. The size was (12.0-30.0) μm long and (6.0～12.0) μm wide (n=20). The cultural and morphological characteristics of these isolates were similar to those of Alternaria alternata (Simmons et al. 2007; Garibaldi et al. 2020). For accurate identification, genomic DNA was extracted from the mycelia of representative isolate (JSNZ). The internal transcribed spacer (ITS), 18S nrDNA (SSU), translation elongation factor 1-alpha (Tef1-α) and endopolygalacturonase (endoPG) sequences were amplified with the primer pairs of ITS1/ITS4, NS1/NS4, EFI-728F/EFI-986R and EPG-specific/EPG-3b, respectively (Woudenberg et al, 2013). The sequences were deposited in GeneBank under accessions MZ360963 (ITS), MZ677478 (SSU), OK274117(Tef1-α) and OK513186 (endoPG). BLAST analysis of the sequences of ITS, SSU, Tef1-α and endoPG showed >99% identity with those of A. alternata MK108918(561/601bp), KX609765 (1030/1035bp), LC132712 (281/281bp) and MT185591(459/483bp), respectively. A neighbor-joining phylogenetic tree was generated based on the concatenated data from sequences of ITS, SSU and Tef1-α using MEGA5.1, which clustered the present isolate with A. alternata strain CBS916.96 with high bootstrap support (100%). Based on cultural characteristics and phylogenetic analysis, the current isolate associated with leaf spot of L. japonicum was identified as A. alternata. Pathogenicity test was performed on three healthy L. japonicum on campus. Three healthy leaves of each plant were wounded with one sterile needle and inoculated with a 5-mm-diameter mycelial plug using sterile PDA plugs as control. The inoculated plants were covered with plastic bags and sprayed with water every 24 hours to maintain a high temperature and humidity environment. The experiment was repeated three times. After 12-days of incubation, symptoms were apparent on pathogen-inoculated plants, while the control plants remained asymptomatic. A. alternata was reisolated from inoculated leaves and matched the morphological and molecular characteristics of the original isolates, thus fulfilling Koch's postulates. To the best of our knowledge, this is the first report of a leaf spot disease caused by A. alternata in L. japonicum in China. Its identification will establish a foundation for managing the disease in China.

Berberis fortune (Lindl.) is commonly used in Chinese traditional medicine (Liu et al. 2020). In April 2020, white powdery colonies covering up to 100% of both upper leaf surfaces and calyces were observed on this species growing on Anhui Agricultural University campus (31°51'51″N; 117°15'31″E) in Hefei City, Anhui Province, China. Sporulating mycelia were white and effuse. Conidiophores were erect, with straight, cylindrical foot cells, 20 to 26 × 9 to 12 μm (average: 24 × 11 µm) (n = 30), followed by one to three shorter cells, and producing conidia in chains. Conidia were ellipsoid-ovoid, subcylindrical, and measured 27 to 36 × 12 to 16.5 µm (average: 32.4 × 14.1 µm) (n = 50). For accurate identification, DNA was extracted from the mycelia, which were collected by scraping symptomatic leaves. The internal transcribed spacer (ITS) was amplified and sequenced using primers ITS1/ITS4. The 623-bp ITS (GenBank accession no. MT449013) showed 99% identity with those of Erysiphe berberidis LC010057 (Takamatsu et al. 2015), KY661153 and KY660920. Based on morphological characteristics and phylogenetic analysis, the powdery mildew fungus on B. fortunei was identified as E. berberidis (Glawe, D. A. 2003). Ten leaves on an asymptomatic B. fortunei were inoculated by gently pressing diseased leaves against the surface of healthy leaves. Ten non-inoculated plants served as controls. All plants were maintained in a greenhouse at 22 to 25°C and >80% relative humidity. Inoculated plants developed powdery mildew colonies after 14 days, whereas uninoculated plants remained healthy. Morphological and molecular characters of the powdery mildew fungus on artificially inoculated plants were identical to those on naturally infected B. fortune. Previously in Siberia, Russia, powdery mildew on woody plants has been reported to be caused by E. berberidis (Tomoshevich M. A. 2019). However, this is the first report of powdery mildew caused by E. berberidis on B. fortunei in China. Its identification will establish a foundation for controlling the disease in China.