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1.
J Sci Food Agric ; 102(9): 3762-3770, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34921405

RESUMEN

BACKGROUND: Selenium (Se) is a needed trace element for animals and humans. Many fungi have effective mechanisms to acquire, transform and accumulate Se in organic form. In this study, the effects of inorganic Se (sodium selenite) on the medicinal fungus Inonotus hispidus was investigated. RESULTS: Inonotus hispidus was capable of tolerating up to 3.85 mmol L-1 selenite, at which ~85% growth inhibition was seen, with 50% growth inhibition occurring at ~1 mmol L-1 selenite. Growth in 0.29 mmol L-1 Se resulted in I. hispidus mycelium with 115 times higher Se levels compared to growth in standard media, and an organic Se content of 86% to total Se content. The influence of Se accumulation on morphological features of I. hispidus were examined by microscopic and scanning electron microscopic observation. These data revealed significant shrinkage and deformations of I. hispidus hyphae with decreased branching and collapse of clamp connections under higher Se stress. However, conidial production in I. hispidus increased dramatically. The influence of Se on mycelial growth could be recovered by reinoculation in standard media. Se accumulation had only minimal impacts on the yield of the potential selenocompounds such as amino acids, proteins and polysaccharides. By contrast, Se-enriched I. hispidus mycelium was of higher quality due to reduction in crude fat and total ash contents. CONCLUSIONS: These data provide basic and applied information on the feasibility of producing selenized I. hispidus as an enriched and better quality product. © 2021 Society of Chemical Industry.


Asunto(s)
Selenio , Hongos/metabolismo , Inonotus , Micelio , Selenio/análisis , Selenito de Sodio/metabolismo
2.
Can J Microbiol ; 62(7): 579-87, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27192440

RESUMEN

The insect pathogenic fungus Aschersonia placenta is a highly effective pathogen of whiteflies and scale insects. However, few genetic tools are currently available for studying this organism. Here we report on the conditions for the production of transformable A. placenta protoplasts using an optimized protocol based on the response surface method (RSM). Critical parameters for protoplast production were modelled by using a Box-Behnken design (BBD) involving 3 levels of 3 variables that was subsequently tested to verify its ability to predict protoplast production (R(2) = 0.9465). The optimized conditions resulted in the highest yield of protoplasts ((4.41 ± 0.02) × 10(7) cells/mL of culture, mean ± SE) when fungal cells were treated with 26.1 mg/mL of lywallzyme for 4 h of digestion, and subsequently allowed to recover for 64.6 h in 0.7 mol/L NaCl-Tris buffer. The latter was used as an osmotic stabilizer. The yield of protoplasts was approximately 10-fold higher than that of the nonoptimized conditions. Generated protoplasts were transformed with vector PbarGPE containing the bar gene as the selection marker. Transformation efficiency was 300 colonies/(µg DNA·10(7) protoplasts), and integration of the vector DNA was confirmed by PCR. The results show that rational design strategies (RSM and BBD methods) are useful to increase the production of fungal protoplasts for a variety of downstream applications.


Asunto(s)
Algoritmos , Técnicas Genéticas , Hypocreales/genética , Protoplastos , Transformación Genética , Ósmosis
3.
Microorganisms ; 12(6)2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38930443

RESUMEN

Protected areas are widely considered an essential strategy for biodiversity conservation. Dictyostelids are unique protists known to have important ecological functions in promoting soil and plant health through their top-down regulation of ecosystem processes, such as decomposition, that involve bacterial populations. But the relationship between dictyostelid diversity within protected areas remains poorly understood, especially on a large scale. Herein, we report data on the distribution of dictyostelids, identified with ITS + SSU rRNA molecular and morphology-based taxonomy, from soil samples collected in the Fanjing Mountain protected area of Guizhou Province, Southwest China. We compared the biodiversity data of dictyostelids in Fanjing Mountain with similar data from previously sampled sites in four other protected areas, including Changbai Mountain (CB), Gushan Mountain (GS), Baiyun Mountain (BY), and Qinghai-Tibet Plateau (QT) in China. We identified four species of dictyostelids belonging to three genera (Dictyostelium, Heterostelium, and Polysphondylium) and herein provide information on the taxonomy of these species. Two species (Heterostelium pallidum and Dictyostelium purpureum) are common and widely distributed throughout the world, but one species (Polysphondylium fuscans) was new to China. Our data indicate that there is no distinguishable significant correlation between the dictyostelid species studied and environmental factors. Overall, the similarity index between Baiyun Mountain in Henan Province and Fanjing Mountain in Guizhou Province, located at approximately the same longitude, is the highest, and the Jaccard similarity coefficients (Jaccard index) of family, genus, and species are 100%, 100%, and 12.5%, respectively. From a species perspective, species in the same climate zone are not closely related, but obvious geographical distributions are evident in different climate zones. This preliminary study provided evidence of the ecological adaptation of dictyostelids to different biological niches.

4.
J Fungi (Basel) ; 10(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38921368

RESUMEN

Members of the fungal order Diaporthales are sac fungi that include plant pathogens (the notorious chestnut blight fungus), as well as saprobes and endophytes, and are capable of colonizing a wide variety of substrates in different ecosystems, habitats, and hosts worldwide. However, many Diaporthales species remain unidentified, and various inconsistencies within its taxonomic category remain to be resolved. Here, we aimed to identify and classify new species of Diaporthales by using combined morphological and molecular characterization and coupling this information to expand our current phylogenetic understanding of this order. Fungal samples were obtained from dead branches and diseasedleaves of Camellia (Theaceae) and Castanopsis (Fagaceae) in Fujian Province, China. Based on morphological characteristics and molecular phylogenetic analyses derived from the combined nucleotide sequences of loci of the internal transcribed spacer regions with the intervening 5.8S nrRNA gene (ITS), the 28S large subunit of nuclear ribosomal RNA gene (LSU), the translation elongation factor 1-α gene (tef1), the partial beta-tubulin gene (tub2), and partial RNA polymerase II second-largest subunit gene (rpb2), three new species of Diaporthales were identified and characterized. They are as follows: Chrysofolia camelliae sp. nov., Dendrostoma castanopsidis sp. nov., and Pseudoplagiostoma wuyishanense sp. nov. They are described and illustrated. This study extends our understanding of species diversity within the Diaporthales.

5.
J Fungi (Basel) ; 10(1)2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38248979

RESUMEN

The characterization of natural fungal diversity impacts our understanding of ecological and evolutionary processes and can lead to novel bioproduct discovery. Russula and Lactarius, both in the order Russulales, represent two large genera of ectomycorrhizal fungi that include edible as well as toxic varieties. Based on morphological and phylogenetic analyses, including nucleotide sequences of the internal transcribed spacer (ITS), the 28S large subunit of ribosomal RNA (LSU), the second largest subunit of RNA polymerase II (RPB2), the ribosomal mitochondrial small subunit (mtSSU), and the translation elongation factor 1-α (TEF1-α) gene sequences, we here describe and illustrate two new species of Russula and one new species of Lactarius from southern China. These three new species are: R. junzifengensis (R. subsect. Virescentinae), R. zonatus (R. subsect. Crassotunicatae), and L. jianyangensis (L. subsect. Zonarii).

6.
J Fungi (Basel) ; 10(3)2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38535196

RESUMEN

The Asian water plantain, Alisma orientale (Sam.) Juzep, is a traditional Chinese medicinal plant. The dried tubers of the Alisma orientale, commonly referred to as Alismatis rhizome (AR), have long been used in traditional Chinese medicine to treat a variety of diseases. Soil properties and the soil microbial composition are known to affect the quality and bioactivity of plants. Here, we sought to identify variations in soil fungal communities and soil properties to determine which would be optimal for cultivation of A. orietale. Soil properties, heavy metal content, and pesticide residues were determined from soils derived from four different agricultural regions around Shaowu City, Fujian, China, that had previously been cultivated with various crops, namely, Shui Dao Tu (SDT, rice), Guo Shu Tu (GST, pecan), Cha Shu Tu (CST, tea trees), and Sang Shen Tu (SST, mulberry). As fungi can either positively or negatively impact plant growth, the fungal communities in the different soils were characterized using long-read PacBio sequencing. Finally, we examined the quality of A. orientale grown in the different soils. Our results show that fungal community diversity of the GST soil was the highest with saprotrophs the main functional modes in these and SDT soils. Our data show that GST and SDT soils were most suitable for A. orientale growth, with the quality of the AR tubers harvested from GST soil being the highest. These data provide a systematic approach at soil properties of agricultural lands in need of replacement and/or rotating crops. Based on our findings, GST was identified as the optimal soil for planting A. orientale, providing a new resource for local farmers.

7.
Front Microbiol ; 15: 1379879, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38680916

RESUMEN

Leaves of Camellia sinensis plants are used to produce tea, one of the most consumed beverages worldwide, containing a wide variety of bioactive compounds that help to promote human health. Tea cultivation is economically important, and its sustainable production can have significant consequences in providing agricultural opportunities and lowering extreme poverty. Soil parameters are well known to affect the quality of the resultant leaves and consequently, the understanding of the diversity and functions of soil microorganisms in tea gardens will provide insight to harnessing soil microbial communities to improve tea yield and quality. Current analyses indicate that tea garden soils possess a rich composition of diverse microorganisms (bacteria and fungi) of which the bacterial Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Chloroflexi and fungal Ascomycota, Basidiomycota, Glomeromycota are the prominent groups. When optimized, these microbes' function in keeping garden soil ecosystems balanced by acting on nutrient cycling processes, biofertilizers, biocontrol of pests and pathogens, and bioremediation of persistent organic chemicals. Here, we summarize research on the activities of (tea garden) soil microorganisms as biofertilizers, biological control agents and as bioremediators to improve soil health and consequently, tea yield and quality, focusing mainly on bacterial and fungal members. Recent advances in molecular techniques that characterize the diverse microorganisms in tea gardens are examined. In terms of viruses there is a paucity of information regarding any beneficial functions of soil viruses in tea gardens, although in some instances insect pathogenic viruses have been used to control tea pests. The potential of soil microorganisms is reported here, as well as recent techniques used to study microbial diversity and their genetic manipulation, aimed at improving the yield and quality of tea plants for sustainable production.

8.
Can J Microbiol ; 59(2): 97-101, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23461516

RESUMEN

The fungus Aschersonia placenta FJSM was evaluated for control of the sweet potato whitefly, Bemisia tabaci. Bemisia tabaci nymphs (1st-4th instars) on tomato plants in the greenhouse (25-27 °C, 70%-85% relative humidity) were sprayed with suspensions containing 0, 10(4), 10(5), 10(6), 10(7), or 10(8) A. placenta FJSM conidia/mL. Mortality of fungus-treated 1st to 3rd instar nymphs ranged from 93% to 100% but was <25% for 4th instar nymphs; the fungus sporulated from 70% to 80% of the fungus-treated B. tabaci cadavers. LD50 and LD90 values decreased with time after treatment and increased with instar. LT50 values decreased with conidial concentration. The data were then described with time-dose-mortality models. The results indicate that A. placenta FJSM has potential as a mycoinsecticide for control of B. tabaci.


Asunto(s)
Hemípteros/microbiología , Hypocreales/fisiología , Modelos Biológicos , Control Biológico de Vectores/métodos , Animales , Dosificación Letal Mediana , Ninfa/microbiología , Análisis de Supervivencia , Factores de Tiempo
9.
Can J Microbiol ; 59(7): 443-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23826952

RESUMEN

Metarhizium anisopliae is a well-characterized entomopathogenic fungus that attacks a variety of insects. Its conidia are involved in its propagation and also in its infection of host insects. To investigate the protein expression profiles and to identify the proteins related to development and pathogenesis, we performed a comparative proteomic analysis of the conidia and mycelia of an M. anisopliae strain (Ma1291). The analysis used 2-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We detected 898 ± 37 protein spots in conidia and 1072 ± 24 in mycelia of strain Ma1291. A comparison of the 2 protein-expression profiles indicated that only 28% of protein spots were common to both developmental stages. Finally, we identified 30 proteins (19 from conidia and 11 from mycelia). The identified proteins exclusive to conidia were those involved in protective processes, appressorium formation, and degradation of the host cuticle (protease PR1H). The identified proteins exclusive to mycelia included major proteins participating in biosynthetic and energy metabolism, such as UTP-glucose-1-phosphate uridylyltransferase and heat shock protein 70. This research provides the first proteomic analysis of different developmental stages of M. anisopliae, and the results should facilitate clarification of the molecular basis of these epigenetic variations.


Asunto(s)
Proteínas Fúngicas/análisis , Insectos/microbiología , Metarhizium/química , Metarhizium/crecimiento & desarrollo , Micelio/química , Esporas Fúngicas/química , Animales , Electroforesis en Gel Bidimensional , Proteínas Fúngicas/metabolismo , Metarhizium/metabolismo , Metarhizium/patogenicidad , Proteómica , Virulencia
10.
Exp Parasitol ; 135(1): 96-101, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23831035

RESUMEN

The fungi Hirsutella rhossiliensis and Hirsutella minnesotensis generally parasitize only plant-parasitic nematodes in nature but parasitize the bacterivorous nematode Caenorhabditis elegans on agar plates. To establish a model system for studying the interaction between fungi and nematodes, we compared the parasitism of the first- to fourth-stage larvae (L1-L4) of C. elegans and second-stage juvenile (J2) of Heterodera glycines by twenty isolates of Hirsutella spp. Although parasitism differed substantially among isolates, both H. minnesotensis and H. rhossiliensis parasitized a higher percentage of H. glycines J2s than of C. elegans larvae. Parasitism of C. elegans L1s was correlated with parasitism of H. glycines J2s. Parasitism of C. elegans by H. rhossiliensis and H. minnesotensis was negatively correlated with larva size and motility, i.e., parasitism was higher for the younger stages. The C. elegans L1 is recommended for studying parasitism of nematodes by H. rhossiliensis and H. minnesotensis.


Asunto(s)
Caenorhabditis elegans/microbiología , Hypocreales/fisiología , Tylenchoidea/microbiología , Análisis de Varianza , Animales , Caenorhabditis elegans/crecimiento & desarrollo , Larva/microbiología , Tylenchoidea/crecimiento & desarrollo
11.
J Invertebr Pathol ; 112(2): 108-15, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23174147

RESUMEN

The culture media for mycelial growth and sporulation of the entomopathogenic fungus Aschersonia placenta were optimized using the response surface method (RSM). Interactions of medium components and the optimization of a biphasic production system were studied using Box-Behnken design (BBD) with three levels of three variables. Experimentation confirmed that the model developed based on RSM and BBD successfully predicted mycelia production (R(2) = 0.9336) and conidia production (R(2) = 0.9532). In the first phase, mycelial dry weight was highest (2.14 ± 0.17 g per 100ml of culture, mean±SE) when the concentrations (g/l) of glucose, vitamin B(6), and MgSO(4)·7H(2)O were 31.4, 11.5, and 0.64, respectively. In the second phase, conidia production was highest (9.31 ± 0.48 × 10(7)sporespercm(2)) after 18d of cultivation in the medium containing 33.8 g/l of millet, 1.11 g/l of KH(2)PO(4), and 0.37 g/l of MgSO(4). Mycelial and conidial yields were 3.6- and 10-fold greater, respectively, with the optimized media than with the non-optimized basal media. The results indicate that RSM and BBD methods are effective for increasing the production of A. placenta mycelia and conidia.


Asunto(s)
Biotecnología/métodos , Medios de Cultivo/metabolismo , Fermentación/fisiología , Hypocreales/crecimiento & desarrollo , Micelio/crecimiento & desarrollo , Esporas/fisiología , Reactores Biológicos , Medios de Cultivo/química , Modelos Biológicos , Control Biológico de Vectores/métodos
12.
Microbiol Spectr ; 11(6): e0173223, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37962389

RESUMEN

IMPORTANCE: Soil protists are an essential yet seriously understudied component of the soil microbiome. In this study, 11 new records of dictyostelids belonging to 2 orders, 3 families, and 4 genera were identified from 99 soil samples collected from different elevations and habitats in central Gansu and the southeastern and southcentral portions of Guizhou Province, China. We found that dictyostelid communities were significantly different between Gansu and Guizhou Provinces, apparently in response to different environmental factors. Moreover, dictyostelids were found to have the highest species diversity in mixed forests. Soil pH, temperature, and elevation were determined to be the primary factors that affect the distribution and occurrence of dictyostelids in Guizhou and Gansu Provinces. This work supplements the survey data available for dictyostelids elsewhere in China. These new findings have significant implications for our understanding of the diversity of soil microorganisms.


Asunto(s)
Dictyosteliida , Humanos , Suelo , Granjas , China , Bosques , Microbiología del Suelo
13.
Front Microbiol ; 14: 1229705, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664128

RESUMEN

Introduction: Species of Melanconiella include a diverse array of plant pathogens as well as endophytic fungi. Members of this genus have been frequently collected from the family Betulaceae (birches) in Europe and North America. Little, however, if known concerning the distribution of Melanconiella and/or their potential as pathogens of other plant hosts. Methods: Fungi were noted and isolated from diseased leaves of Loropetalum chinense (Chinese fringe flower) and Camellia sinensis (tea) in Fujian Province, China. Genomic DNA was extracted from fungal isolates and the nucleotide sequences of four loci were determined and sued to construct phylogenetic trees. Morphological characteristics of fungal structures were determined via microscopic analyses. Results: Four strains and two new species of Melanconiella were isolated from infected leaves of L. chinense and C. sinensis in Fujian Province, China. Based on morphology and a multi-gene phylogeny of the internal transcribed spacer regions with the intervening 5.8S nrRNA gene (ITS), the 28S large subunit of nuclear ribosomal RNA (LSU), the second largest subunit of RNA polymerase II (RPB2), and the translation elongation factor 1-α gene (TEF1-α), Melanconiellaloropetali sp. nov. and Melanconiellacamelliae sp. nov. were identified and described herein. Detailed descriptions, illustrations, and a key to the known species of Melanconiella are provided. Discussion: These data identify new species of Melanconiella, expanding the potential range and distribution of these dark septate fungi. The developed keys provide a reference source for further characterization of these fungi.

14.
Front Microbiol ; 14: 1164511, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256050

RESUMEN

Introduction: Tea is one of the most widely consumed beverages around the world. Larvae of the moth, Ectropis obliqua Prout (Geometridae, Lepidoptera), are one of the most destructive insect pests of tea in China. E. obliqua is a polyphagus insect that is of increasing concern due to the development of populations resistant to certain chemical insecticides. Microbial biological control agents offer an environmentally friendly and effective means for insect control that can be compatible with "green" and organic farming practices. Methods: To identify novel E. obliqua biological control agents, soil and inset cadaver samples were collected from tea growing regions in the Fujian province, China. Isolates were analyzed morphologically and via molecular characterization to identity them at the species level. Laboratory and greenhouse insect bioassays were used to determine the effectiveness of the isolates for E. obliqua control. Results: Eleven isolates corresponding to ten different species of Metarhizium were identified according to morphological and molecular analyses from soil and/or insect cadavers found on tea plants and/or in the surrounding soil sampled from eight different regions within the Fujian province, China. Four species of Metarhizium including M. clavatum, M. indigoticum, M. pemphigi, and M. phasmatodeae were documented for the first time in China, and the other species were identified as M. anisopliae, M. brunneum, M. lepidiotae, M. majus, M. pinghaense, and M. robertsii. Insect bioassays of the eleven isolates of Metarhizium revealed significant variation in the efficacy of each isolate to infect and kill E. obliqua. Metarhizium pingshaense (MaFZ-13) showed the highest virulence reaching a host target mortality rate of 93% in laboratory bioassays. The median lethal concentration (LC50) and median lethal time (LT50) values of M. pingshaense MaFZ-13 were 9.6 × 104 conidia/mL and 4.8 days, respectively. Greenhouse experiments and a time-dose-mortality (TDM) models were used to further evaluate and confirm the fungal pathogenic potential of M. pingshaense MaFZ-13 against E. obliqua larvae. Discussion: Isolation of indigenous microbial biological control agents targeting specific pests is an effective approach for collecting resources that can be exploited for pest control with lowered obstacles to approval and commercialization. Our data show the presence of four different previously unreported Metarhizium species in China. Bioassays of the eleven different Metarhizium strains isolated revealed that each could infect and kill E. obliqua to different degrees with the newly isolated M. pingshaense MaFZ-13 strain representing a particularly highly virulent isolate potentially applicable for the control of E. obliqua larvae.

15.
Front Microbiol ; 14: 1288066, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38094633

RESUMEN

Introduction: Understanding microbial communities in diverse ecosystems is crucial for unraveling the intricate relationships among microorganisms, their environment, and ecosystem processes. In this study, we investigated differences in the fungal community structure and diversity in soils from two contrasting climatic and vegetation conditions: the Xinjiang western China plateau and the Fujian southeastern coastal province. Methods: A total of 36 soil samples collected from two climatic regions were subjected to high-throughput ITS gene sequencing for fungal community analysis. In conjunction soil physicochemical properties were assessed and compared. Analyses included an examination of the relationship of fungal community structure to environmental factors and functional profiling of the community structure was using the FUNGuild pipeline. Results: Our data revealed rich fungal diversity, with a total of 11 fungal phyla, 31 classes, 86 orders, 200 families, 388 genera, and 515 species identified in the soil samples. Distinct variations in the physicochemical properties of the soil and fungal community structure were seen in relation to climate and surface vegetation. Notably, despite a colder climate, the rhizosphere soil of Xinjiang exhibited higher fungal (α-)diversity compared to the rhizosphere soil of Fujian. ß-diversity analyses indicated that soil heterogeneity and differences in fungal community structure were primarily influenced by spatial distance limitations and vegetation type. Furthermore, we identified dominant fungal phyla with significant roles in energy cycling and organic matter degradation, including members of the Sordariomycetes, Leotiomycetes, Archaeosporomycetes, and Agaricomycetes. Functional analyses of soil fungal communities highlighted distinct microbial ecological functions in Xinjiang and Fujian soils. Xinjiang soil was characterized by a focus on wood and plant saprotrophy, and endophytes, whereas in Fujian soil the fungal community was mainly associated with ectomycorrhizal interactions, fungal parasitism, and wood saprotrophy. Discussion: Our findings suggest fungal communities in different climatic conditions adapt along distinct patterns with, plants to cope with environmental stress and contribute significantly to energy metabolism and material cycling within soil-plant systems. This study provides valuable insights into the ecological diversity of fungal communities driven by geological and environmental factors.

16.
J Fungi (Basel) ; 9(11)2023 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-37998887

RESUMEN

The insect pathogenic fungus, Ascosphaera apis, is the causative agent of honeybee chalk brood disease. Amylases are secreted by many plant pathogenic fungi to access host nutrients through the metabolism of starch, and the identification of new amylases can have important biotechnological applications. Production of amylase by A. apis in submerged culture was optimized using the response surface method (RSM). Media composition was modeled using Box-Behnken design (BBD) at three levels of three variables, and the model was experimentally validated to predict amylase activity (R2 = 0.9528). Amylase activity was highest (45.28 ± 1.16 U/mL, mean ± SE) in media composed of 46 g/L maltose and1.51 g/L CaCl2 at a pH of 6.6, where total activity was ~11-fold greater as compared to standard basal media. The enzyme was purified to homogeneity with a 2.5% yield and 14-fold purification. The purified enzyme had a molecular weight of 75 kDa and was thermostable and active in a broad pH range (> 80% activity at a pH range of 7-10), with optimal activity at 55 °C and pH = 7.5. Kinetic analyses revealed a Km of 6.22 mmol/L and a Vmax of 4.21 µmol/mL·min using soluble starch as the substrate. Activity was significantly stimulated by Fe2+ and completely inhibited by Cu2+, Mn2+, and Ba2+ (10 mM). Ethanol and chloroform (10% v/v) also caused significant levels of inhibition. The purified amylase essentially exhibited activity only on hydrolyzed soluble starch, producing mainly glucose and maltose, indicating that it is an endo-amylase (α-amylase). Amylase activity peaked at 99.38 U/mL fermented in a 3.7 L-bioreactor (2.15-fold greater than what was observed in flask cultures). These data provide a strategy for optimizing the production of enzymes from fungi and provide insight into the α-amylase of A. apis.

17.
Foods ; 12(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37569205

RESUMEN

Daqu is a traditional starter for Baijiu fermentation and is produced by spontaneous fermentation of ground and moistened barley or wheat. The quality of Daqu is traditionally evaluated based on physicochemical and subjective sensory parameters without microbiological analysis. Here, we compared the physicochemical characteristics of qualified (QD) and inferior (ID) Daqu, their microbial communities based on plate counting and PacBio SMRT sequencing of rRNA gene libraries, and their impacts on Baijiu fermentation. The results showed that the glucoamylase and α-amylase activities of QD were significantly higher than those of ID. The counts of yeasts and relative abundances of functional microbes, especially the amylolytic bacterium Bacillus licheniformis and fungi Saccharomycopsis fibuligera and Lichtheimia ramosa, were significantly higher in QD than in ID. The laboratory-scale Baijiu fermentation tests showed that the relative abundances of the amylolytic microbes were higher in the QD than the ID fermentation set, resulting in more efficient fermentation, as indicated by more weight loss and higher moisture content in the former. Consequently, more glycerol, acetic acid, ethanol, and other volatile compounds were produced in the QD than in the ID fermentation set. The results suggest that Daqu quality is determined by, and can be evaluated based on, its microbial community.

18.
J Fungi (Basel) ; 9(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38132776

RESUMEN

Little is known concerning terpenoids produced by members of the fungal order Ophiostomales, with the member Harringtonia lauricola having the unique lifestyle of being a beetle symbiont but potentially devastating tree pathogen. Nine known terpenoids, including six labdane diterpenoids (1-6) and three hopane triterpenes (7-9), were isolated from H. lauricola ethyl acetate (EtOAc) extracts for the first time. All compounds were tested for various in vitro bioactivities. Six compounds, 2, 4, 5, 6, 7, and 9, are described functionally. Compounds 2, 4, 5, and 9 expressed potent antiproliferative activity against the MCF-7, HepG2 and A549 cancer cell lines, with half-maximal inhibitory concentrations (IC50s) ~12.54-26.06 µM. Antimicrobial activity bioassays revealed that compounds 4, 5, and 9 exhibited substantial effects against Gram-negative bacteria (Escherichia coli and Ralstonia solanacearum) with minimum inhibitory concentration (MIC) values between 3.13 and 12.50 µg/mL. Little activity was seen towards Gram-positive bacteria for any of the compounds, whereas compounds 2, 4, 7, and 9 expressed antifungal activities (Fusarium oxysporum) with MIC values ranging from 6.25 to 25.00 µg/mL. Compounds 4, 5, and 9 also displayed free radical scavenging abilities towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide (O2-), with IC50 values of compounds 2, 4, and 6 ~3.45-14.04 µg/mL and 22.87-53.31 µg/mL towards DPPH and O2-, respectively. These data provide an insight into the biopharmaceutical potential of terpenoids from this group of fungal insect symbionts and plant pathogens.

19.
Int J Syst Evol Microbiol ; 62(Pt 12): 3095-3098, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22863990

RESUMEN

Two strains isolated from rotten wood were included in the Saccharomyces group based on morphological characteristics. However, rRNA gene sequence analyses (including the 18S rRNA gene, 26S rRNA gene D1/D2 domain and internal transcribed spacer region) indicated that these two strains represent a novel species of Naumovozyma, for which the name Naumovozyma baii sp. nov. is proposed (type strain: BW 22(T) = CGMCC 2.04520(T) = CBS 12642(T)). The MycoBank number of the new species is MB800484.


Asunto(s)
Filogenia , Saccharomycetales/clasificación , Saccharomycetales/aislamiento & purificación , Árboles , Madera/genética , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Técnicas de Tipificación Micológica , ARN Ribosómico/genética , ARN Ribosómico 18S/genética , Saccharomycetales/genética , Análisis de Secuencia de ADN
20.
Antonie Van Leeuwenhoek ; 102(1): 45-51, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22354388

RESUMEN

In a survey of ballistoconidium-forming yeast diversity in the phyllosphere, five strains from wilting plant leaves collected from Kanas Nature Reserve in Xinjiang province, China were selected based on morphological comparison. These strains formed pinkish-white colonies and large bilaterally symmetrical ballistoconidia. Molecular phylogenetic analyses based on the 26S rRNA D1/D2 domain and ITS region sequences showed that these strains belonged to the Udeniomyces clade in the Cystofilobasidiales. They differ from the described Udeniomyces species significantly in the rRNA sequences as well as physiological criteria. Therefore, a new species Udeniomyces kanasensis sp. nov. (type strain XJ 6E2(T)=CGMCC 2.02627 (T)=CBS 12488 (T)) is proposed to accommodate these strains. The MycoBank number of the new species is MB 563659.


Asunto(s)
Basidiomycota/clasificación , Basidiomycota/aislamiento & purificación , Hojas de la Planta/microbiología , Basidiomycota/genética , Basidiomycota/fisiología , China , Análisis por Conglomerados , ADN de Hongos/química , ADN de Hongos/genética , ADN Ribosómico/química , ADN Ribosómico/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Filogenia , Pigmentos Biológicos/metabolismo , ARN de Hongos/genética , ARN Ribosómico/genética , Análisis de Secuencia de ADN , Esporas Fúngicas/citología
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