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Marine Drugs Feb 2019Five new (fusarisolins A⁻E, to ) and three known ( to ) polyketides were isolated from the marine-derived fungus H918, along with six known phenolics ( to ). Their...
Five new (fusarisolins A⁻E, to ) and three known ( to ) polyketides were isolated from the marine-derived fungus H918, along with six known phenolics ( to ). Their structures were established by comprehensive spectroscopic data analyses, methoxyphenylacetic acid (MPA) method, chemical conversion, and by comparison with data reported in the literature. Compounds and are the first two naturally occurring 21 carbons polyketides featuring a rare β- and γ-lactone unit, respectively. All isolates ( to ) were evaluated for their inhibitory effects against tea pathogenic fungus and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase gene expression. Compound showed potent antifungal activity with an ED value of 55 μM, while , , , and significantly inhibited HMG-CoA synthase gene expression.
Topics: Antifungal Agents; Biological Products; Fusarium; Hydroxymethylglutaryl-CoA Synthase; Molecular Conformation; Polyketides
PubMed: 30791608
DOI: 10.3390/md17020125 -
Scientific Reports Apr 2021The global demand for fine-flavour cocoa has increased worldwide during the last years. Fine-flavour cocoa offers exceptional quality and unique fruity and floral...
The global demand for fine-flavour cocoa has increased worldwide during the last years. Fine-flavour cocoa offers exceptional quality and unique fruity and floral flavour attributes of high demand by the world's elite chocolatiers. Several studies have highlighted the relevance of cocoa fermentation to produce such attributes. Nevertheless, little is known regarding the microbial interactions and biochemistry that lead to the production of these attributes on farms of industrial relevance, where traditional fermentation methods have been pre-standardized and scaled up. In this study, we have used metagenomic approaches to dissect on-farm industrial fermentations of fine-flavour cocoa. Our results revealed the presence of a shared core of nine dominant microorganisms (i.e. Limosilactobacillus fermentum, Saccharomyces cerevisiae, Pestalotiopsis rhododendri, Acetobacter aceti group, Bacillus subtilis group, Weissella ghanensis group, Lactobacillus_uc, Malassezia restricta and Malassezia globosa) between two farms located at completely different agro-ecological zones. Moreover, a community metabolic model was reconstructed and proposed as a tool to further elucidate the interactions among microorganisms and flavour biochemistry. Our work is the first to reveal a core of microorganisms shared among industrial farms, which is an essential step to process engineering aimed to design starter cultures, reducing fermentation times, and controlling the expression of undesirable phenotypes.
Topics: Cacao; Chocolate; Fermentation; Flavoring Agents; Food Microbiology; Metagenome
PubMed: 33883642
DOI: 10.1038/s41598-021-88048-3 -
Plants (Basel, Switzerland) Jun 2020Citrus trees with cankers and dieback symptoms were observed in Bushehr (Bushehr province, Iran). Isolations were made from diseased cankers and branches. Recovered...
Citrus trees with cankers and dieback symptoms were observed in Bushehr (Bushehr province, Iran). Isolations were made from diseased cankers and branches. Recovered fungal isolates were identified using cultural and morphological characteristics, as well as comparisons of DNA sequence data of the nuclear ribosomal DNA-internal transcribed spacer region, translation elongation factor , β-tubulin, and actin gene regions. , , , , , , , , , , sp., , (.) , , (.) (.) , and several isolates of , , and species were obtained from diseased trees. The pathogenicity tests were conducted by artificial inoculation of excised shoots of healthy acid lime trees () under controlled conditions. was the most virulent and caused the longest lesions within 40 days of inoculation. According to literature reviews, this is the first report of and on citrus in Iran. Additionally, we report several species, , and on citrus trees for the first time in the world.
PubMed: 32560035
DOI: 10.3390/plants9060754 -
Plant Disease Sep 2022Gardenia jasminoides Ellis, an important Chinese medicine, is cultivated on approximately 1,400 hectares in China. From August to October 2016, a severe disease...
Gardenia jasminoides Ellis, an important Chinese medicine, is cultivated on approximately 1,400 hectares in China. From August to October 2016, a severe disease affecting leaves, stems, and fruits of G. jasminoides, occurred in Cangnan (120°39'E, 27°48'N), Zhejiang province. Infected leaves or stems became shriveled, and in severe cases, young fruits presented red-brown or yellow necrotic lesions with numerous black spots. More than thirty diseased fruit and stem samples were collected, ten diseased fruits were surfacedisinfected (70% ethanol for 30 s, 1.5% sodium hypochlorite for 1 min) and kept at about 25℃ for 24 h with 80% humidity. The conidial suspension (105 conidia/ml) made of creamy drops secreted from the lesion black spots was spread onto PDA (Potato-Dextrose-Agar) and incubated at 25℃ in the dark for 7 d. Only one isolate (step01) was suspected to be the target pathogen, and other three isolates were Alternaria sp. The colony of step01 was white to grayish with an irregular edge on the front and a white to brown spiral grain on the back. Black pycnidia, produced after 20 d, were globose to subglobose, individual or overlapped, with an ostiole secreting a creamy conidial suspension. Alpha-conidia were aseptate, hyaline, oval to oblong with two oil balls, 7.4-15.9×2.4-4.5 µm (average 10.2×3.3 µm); beta-conidia were hyaline, aseptate, linetype, straight or slightly curled, 15.3-26.5×1.3-2.5 µm (average 20.8×1.6 µm). This isolate resembled Diaporthe sp. (Hansen and Barrett 1938). For species identification, DNA was extracted (Sangon Biotech Rapid Fungi Genomic DNA Isolation Kit - B518229),and the internal transcribed spacer region (ITS), elongation factor (EF1-α), β-Tubulin (TUB), and histone H3 (HIS) of step01 were amplified using the primer pairs ITS1/ITS4, EF1-728F/ EF1-986R, BT-2a /BT-2b and CYLH3F/CYLH3R, respectively (Udayanga et al 2014, Huang et al. 2015).These sequences were submitted to GenBank as KY797655 (ITS), MF158048 (EF1- α), MF158049 (TUB), and MF158050 (HIS). In comparison with the other sequence of Diaporthe sp. using MEGA7.0 (maximum likelihood, bootstrap replications=1,000), step01 showed 100% identity with D. gardeniae. Based on their morphology and molecular identification, step01 was identified as D. gardeniae (syn. Phomopsis gardeniae). Pathogenicity was tested on three one-year-old G. jasminoides plants by stem inoculation. Two or three stems per plant were inoculated by binding a mycelial plug (5 ×12 mm), covered by humid cotton and plastic film, to the tender stem. A total of two plants were treated. Plants were kept at about 25℃ for 4 weeks. Control plants were inoculated with PDA plugs. Leaf blight started from the apex, extended to the stalk, and the leaves finally fell off. Three months after inoculation, symptoms developed on the underlying leaves, the stem was withered with black spots, a pattern like that observed in the field. No symptoms appeared in the control leaves. Five identical colonies were re-isolated from symptomatic tissues and identified again as D. gardeniae, fulfilling the Koch's postulates. Several fungi are associated with canker, leaf spot, and fruit rot in Gardenia throughout China, including Pestalotiopsis sp. (Huang et al. 2006), Botryosphaeria dothidea (Dong et al. 2016), and Phoma sp. (Luo et al. 2016). To the best of our knowledge, this is the first report of D. gardenia infecting G. jasminoides Ellis in Zhejiang Province, China.
PubMed: 36109874
DOI: 10.1094/PDIS-03-22-0460-PDN -
Plant Disease Jun 2023(Burkill) F. H. Chen ex C. Y. Wu & K.M. Feng is a Chinese herbal medicinal plant for treating diseases of the central nervous system and cardiovascular system, widely...
(Burkill) F. H. Chen ex C. Y. Wu & K.M. Feng is a Chinese herbal medicinal plant for treating diseases of the central nervous system and cardiovascular system, widely used as a medicine and health-care product. In May 2022, leaf blight disease was found on leaves of 1-year-old in the plantings (27.904°N, 112.918°E) of Xiangtan City (Hunan) with an area of 10 m. Over 400 plants were investigated, up to 25% of the plants were symptomatic. From the margin of the leaf, the initial symptoms of water-soaked chlorosis and following dry yellow with slight shrinkage appeared. Later, leaf shrinkage became serious and chlorosis enlarged gradually, leading to leaf death and abscission. To identify the causal agent, 20 leaf lesions (4 mm) collected from 20 individual 1-year-old plants were sterilized with 75% ethanol for 10 s, 5% NaOCl for 10 s, rinsed in sterilized water three times, placed on potato dextrose agar (PDA) with lactic acid (0.125%) for inhibition the growth of bacteria, and incubated at 28°C for 7 days (Fang, 1998). Five isolates were obtained from 20 leaf lesions of different plants with the isolation rate of 25% and purified by single sporing, which have similar colony and conidia morphology characteristics. One isolate PB2-a was selected randomly for further identification. Colonies of PB2-a on PDA were white with cottony mycelium, developing concentric circles (top view) or light yellow (back view). Conidia (23.1 ± 2.1 × 5.7 ± 0.8 µm, n=30)were fusiform, straight or slightly curved and contained conic basal cell, three light brown median cells and hyaline conic apical cell with appendages. The rDNA internal transcribed spacer (ITS), the translation elongation factor 1-alpha (), and the β-tubulin (TUB2) genes were amplified from genomic DNA of PB2-a using primers ITS4/ITS5 (White et al. 1990), EF1-526F/EF1-1567R (Maharachchikumbura et al. 2012), and Bt2a/Bt2b (Glass and Donaldson, 1995; O'Donnell and Cigelnik, 1997), respectively. BLAST search of sequenced ITS (OP615100), (OP681464) and TUB2 (OP681465) exhibited > 99% identity with the type strain of OP068 (JQ845947, JQ845946 and JQ845945). Phylogenetic tree of the concatenated sequences was constructed based on the maximum-likelihood method using MEGA-X. Isolate PB2-a was identified as based on morphological and molecular data (Maharachchikumbura et al. 2011; Qi et al. 2022). PB2-a was tested for pathogenicity three times to confirm Koch's postulates. Twenty healthy leaves on 20 1-year-old plants were punctured with sterile needles and inoculated with 50 µl of conidial suspension (1×10 conidia/ml). The controls were inoculated with sterile water. All plants were placed in a greenhouse at 25°C under 80% relative humidity. After 7 days, all inoculated leaves developed leaf blight symptoms identical to those described above, whereas the control plants kept healthy. were reisolated from infected leaves, and identical to those of the originals based on the colony characteristics and the sequenced data of ITS, and TUB2. was reported as a pathogen of leaf blight on (Xu et al. 2022). To our knowledge, this is the first report of causing leaf blight on in Hunan, China. Leaf blight is one of the destructive diseases in production, identification of the pathogen will be useful to develop effective disease management and protect , a medical plant with economic value.
PubMed: 37294156
DOI: 10.1094/PDIS-04-23-0681-PDN -
Plant Disease Aug 2023Morel (Morchella sextelata) is a valuable medicinal and edible mushroom, but the wild yield is seriously insufficient, so several artificial varieties have been...
Morel (Morchella sextelata) is a valuable medicinal and edible mushroom, but the wild yield is seriously insufficient, so several artificial varieties have been developed to alleviate the shortage of wild yield. However, in 2020-2022, apothecium wither symptoms were observed in Nanchong, Sichuan. A total of 30.80% of the morels in the planting base (1.3 km2) showed these symptoms. The initial symptoms were slight white lesions on the surface of apothecium, then the mycelia gradually invaded the interior of the fruiting body, and eventually leading to black and wilt apothecium (Fig. 1a). Fifteen symptomatic morels were collected and ten isolates were obtained using the single spore isolation technique developed by Chomnunti et al. (2014). The morphological characteristics of the ten isolates were similar, which showed dense aerial white mycelia colony texture on PDA, and later forming concentric black mucus (Fig. 1c). The reverse side was yellow (Fig. 1d). The acervulus was floral-shaped and discrete, with smooth walls and measured 120.0 to 400.5 × 15.5 to 40.0 μm (n=10) (Fig. 1e); the conidia were fusiform and hyaline, 21.0 to 28.6 × 6.0 to 7.6 μm in size (n=50), each contained five cells. The apical cell was hyaline, conic and with 2 to 4 tubular apical appendages on the top. The three intermediate cells were brown to olivaceous, doliform to cylindrical, constricted at septa. The basal cell was conic to acute (Fig. 1f). The morphological characteristics were consistent with the published description of Pestalotiopsis trachicarpicola (Maharachchikumbura et al., 2012). PCR was performed with primers ITS1/ITS4 for internal transcribed spacer (ITS) (White et al., 1990), BT2A/BT2B for β-tubulin gene (TUB) (Glass and Donaldson, 1995), and EF1-526F/EF1-1567R for translation elongation factor 1-alpha (TEF-1α) (Roger et al., 1999). The pairwise alignments of ITS, TUB, and TEF-1α sequences was nearly 100% identical to P. trachicarpicola with GenBank accession numbers MT889666.1 (579/585 bp, 99%), MT884145.1 (445/450 bp, 99%), and MW149930.1 (946/958 bp, 99%), respectively. The resulting sequences were deposited in GenBank (Accession no. ITS: OL362082; TUB: OL828342; and TEF-1α: OL905009). Phylogenetic analysis performed with maximum likelihood method used MEGA 7.0 (1000 bootstrap replications) classified WLM5 into the P. trachicarpicola clade (Fig. 2), so we finally confirmed the identity of WLM5 as P. trachicarpicola. To fulfill Koch's postulates, twenty morels were surface disinfected with 2% sodium hypochlorite and then artificially wounded (diameter of 0.5 mm) prior to inoculation with 200 μL conidial suspension (105 conidia/mL), while an equal amount of sterile distilled water was applied to controls. After 4 days, the inoculated fruiting bodies showed symptoms consistent with field infection (Fig. 1b) and P. trachicarpicola was re-isolated using the same protocol, while the control remained asymptomatic. This first report of P. trachicarpicola causing apothecium wither on morel will help develop robust disease management strategies against this emerging fungal pathogen.
PubMed: 37578365
DOI: 10.1094/PDIS-01-23-0027-PDN -
Microbiological Research Nov 2020Diseases in plants are mostly caused by fungi. Fungal interactions with the host can be either biotrophic, necrotrophic or hemibiotrophic. Synergistic polymicrobial...
Diseases in plants are mostly caused by fungi. Fungal interactions with the host can be either biotrophic, necrotrophic or hemibiotrophic. Synergistic polymicrobial interactions have been recently recognized that can also attribute to the occurrence of complex plant diseases. Tea is one of the most widely consumed beverages worldwide, although tea plants are affected by many different diseases causing a significant reduction in global tea production. Blister blight is one such serious and damaging leaf disease of tea. An assessment of blister blight disease was carried out at the tea development center in Umsning, Meghalaya. A considerable number of tea varieties showed characteristic blister blight symptoms that ranged from preliminary yellow spots in the upper leaf surface, matured white sporulating blisters in the lower leaf surface, and delayed brown necrotic lesions throughout the surfaces of the leaves. A total of 42 isolates, 15 from initial, 15 from mature, and 12 from necrotic stages were isolated from the symptomatic leaf samples. Pestalotiopsis and Nigrospora were the two fungi incessantly isolated from the diseased leaves. Colony characteristics that included colony, hyphal, and spore morphologies were examined and mycelial accumulation, sporulation, and sporal germination were determined for all the isolates of Pestalotiopsis and Nigrospora. Molecular analysis based on ITS-RFLP was performed for identification and genetic variability. In vitro pathogenicity assay revealed that Pestalotiopsis spp. and Nigrospora sp. developed distinct characteristics symptoms on greenhouse acclimated TV17 tea clones. To our knowledge, this is the first report of the prevalence of tea blister blight disease in Meghalaya and it is an initial attempt to identify fungal pathogens during different stages of blister blight disease.
Topics: Ascomycota; Camellia sinensis; Genes, rRNA; Hyphae; India; Phylogeny; Plant Diseases; Plant Leaves; Transcription Factors
PubMed: 32799070
DOI: 10.1016/j.micres.2020.126561 -
Microorganisms Dec 2022Lipases (EC 3.1.1.3) are hydrolases that catalyze triglycerides hydrolysis in free fatty acids and glycerol. Among the microorganisms that produce lipolytic enzymes, the...
Lipases (EC 3.1.1.3) are hydrolases that catalyze triglycerides hydrolysis in free fatty acids and glycerol. Among the microorganisms that produce lipolytic enzymes, the entophytic fungi stand out. We evaluated 32 fungi of different genera, Pestalotiopsis, Aspergillus, Trichoderma, Penicillium, Fusarium, Colletotrichum, Chaetomium, Mucor, Botryodiplodia, Xylaria, Curvularia, Neocosmospora and Verticillium, isolated from Euterpe oleracea Mart. (Açaizeiro) from the Brazilian Amazon for lipase activity. The presence of lipase was evidenced by the deposition of calcium crystals. The endophytic Pestalotiopsis sp. (31) and Aspergillus sp. (24) with Pz 0.237 (++++) and 0.5 (++++), respectively, were the ones that showed the highest lipolytic activity in a solid medium. Lipase activity was rated in liquid medium, in a different range of temperatures (°C), pH and time (days). The values obtained in the production of lipase by the endophytic fungi were 94% for Pestalotiopsis sp. (31) and 93.87% for Aspergillus sp. (24). Therefore, it is emphasized that the endophytic fungus isolated the E. oleracea palm may be a potential candidate to produce enzymes of global commercial interest.
PubMed: 36557647
DOI: 10.3390/microorganisms10122394 -
Studies in Mycology Mar 2019Species of are endophytic, plant pathogenic or saprobic, and associated with a wide range of host plants. Recent molecular studies that have attempted to address...
Species of are endophytic, plant pathogenic or saprobic, and associated with a wide range of host plants. Recent molecular studies that have attempted to address familial and generic boundaries of fungi belonging to were based on a limited number of samples and DNA loci. The taxonomy of this group of fungi is therefore still not fully resolved. The aim of the present study is to provide a natural classification for the based on multi-locus phylogenetic analyses, using LSU, ITS, , and loci, in combination with morphological data. A total of 30 well-supported monophyletic clades in are recognised, representing 23 known and seven new genera. Typifications are proposed for the type species of five genera (, , , and ) to stabilise the application of these names. Furthermore, and are synonymised under , and the generic circumscriptions of , , , , , , , and are emended. A total of 51 new species, one and 15 combinations are introduced.
PubMed: 30584265
DOI: 10.1016/j.simyco.2018.11.001 -
Frontiers in Microbiology 2021Three new secondary metabolites pestalothenins A-C (-), including two new humulane-derived sesquiterpeniods ( and ) and one new caryophyllene-derived sesquiterpeniod (),...
Three new secondary metabolites pestalothenins A-C (-), including two new humulane-derived sesquiterpeniods ( and ) and one new caryophyllene-derived sesquiterpeniod (), together with five known compounds (-) were isolated from the crude extract of the plant endophytic fungus (N635). Their structures were elucidated by the extensive analyses of HRESIMS and NMR spectroscopic data. The absolute configurations of - were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. The cytotoxic effects of these compounds were evaluated . Compound showed moderate cytotoxicity against T24 and MCF7 cell lines. In addition, compounds - were also evaluated for antibacterial activity.
PubMed: 33868199
DOI: 10.3389/fmicb.2021.641504