Mycelial Research Articles

Tannin-Reducing Effect and Changes of Physicochemical Properties in Aronia Homogenate after Treatment with Liquid Cultured Mushroom Mycelia

Tannin-Reducing Effect and Changes of Physicochemical Properties in Aronia Homogenate after Treatment with Liquid Cultured Mushroom Mycelia

Inoculant production of Pisolithus sp. in submerged culture under agitation

Ectomycorrhizal fungi inoculation can increase the sustainability of planted forests hence the inoculant production should be optimized. The objective of this study was to determine the agitation speed and time of growth for maximum production of mycelium of D216 isolate of Pisolithus sp. The treatments were established by factorial 6x3, being six agitation conditions and three different times (days) of growth. The kinds of agitation used were: Without agitation, gentle manual agitation every two days and orbital agitation speed of 50, 100, 200 and 250 rpm. The times of growth were 14, 21 and 28 days. The mycelium mass was generally single and remained on the surface of the culture medium when grown without agitation or with manual agitation. Spherical mass units formed under agitation and grew submerged. The dry mass production of mycelium of D216 isolate was higher when grown under agitation of 200 rpm, followed by 250 and 100 rpm. For all agitation system, the production of mycelium did not increase after 14 days. The maximum production of mycelium dry mass of D216 isolate of Pisolithus sp. was obtained in the agitation speed of 200 rpm for 14 days. The elevation of the agitation to 250 rpm decreased the mycelium dry mass production of Pisolithus sp. In the absence or in lower agitation speeds, the mycelium dry mass was minimal. Using the ideal speed for maximum mycelium production and adjusting other growing conditions can decrease the risk of contamination, the production time and cost of the inoculant and encourage the use of this biotechnology. Key words: Ectomycorrhizal fungi, inoculation, mycorrhiza, planted forests.

Extratos de pimentão vermelho (Capsicum annuum) sobre Colletotrichum gloeosporioides in vitro

O presente estudo avaliou o potencial fungitóxico in vitro de extratos de pimentão vermelho (Capsicum annuum L.) sobre o crescimento micelial de Colletotrichum gloeosporioides. O experimento foi conduzido em delineamento inteiramente casualizado em esquema fatorial 2x10, sendo dois tipos de extratos (etanólico e hidroetanólico) aplicados em 10 concentrações (0,0; 0,2; 0,4; 0,6; 0,8; 1,0; 2,0; 3,0; 4,0; e 5,0%). Cada extrato foi incorporado ao meio de cultura BDA (Batata Dextrose Ágar) e vertido em placas de Petri. As placas foram inoculadas com discos de 1 cm de diâmetro contendo micélios do fungo e incubadas durante sete dias a 27±2°C. Para verificar a diferença entre os tratamentos, foram estimadas a porcentagem de inibição de crescimento micelial (PIC) e o índice de velocidade de crescimento micelial (IVCM). Todas as concentrações dos dois extratos de pimentão apresentaram inibição do crescimento micelial de C. gloeosporioides quando comparados à testemunha. A inibição total do crescimento foi obtida quando se utilizou o extrato etanólico na maior concentração (5,0%) e ultrapassando 50% de inibição na concentração de 2%, sendo superior à obtida pelo extrato hidroetanólico que na concentração máxima inibiu apenas 27,5% do crescimento do fungo. Assim, em condições in vitro, o extrato etanólico de pimentão vermelho mostrou-se promissor no controle de C. gloeosporioides. A concentração de 5,0% promoveu o maior efeito inibitório.

꾸지뽕나무 배양 상황버섯 자실체 및 균사체의 면역증진 효과

Polysaccharides produced in microorganisms and plants are known to increase the immune response in the body. We proposed analysis of beta-glucan contents of phellinus linteus fruit body (FB) and mycelium (MC) cultured in cudrania tricuspidata . Also, we examined whether fruit body and mycelium can increase the immune response in cyclophosphamide-induced immunosuppression animal models. We injected cyclophosphamide (50 ㎎/㎏) twice to produce immunosuppression mice. Then, FB (200 ㎎/㎏) and MC (200 ㎎/㎏) were oral administered for 14 days. In order to confirm the immune-enhancing effect of FB and MC, we analyzed spleen weight, the number of immune cells, cytokines, and immunoglobulins levels. Cyclophosphamide decreased the weight of spleen, the number of immune cells. However, FB and MC have significantly increased the weight of spleen, the number of white blood cell, lymphocyte and monocyte. In addition, they have significantly increased immune-related cytokines (IL-2 and IFN-γ) and immunoglobulins (IgA, IgG, IgM) levels. As a results, phellinus linteus fruit body (FB) and mycelium (MC) cultured in cudrania tricuspidata can be used as effective natural materials for immune-enhancing.

Biocontrol of anthracnose on yellow passion fruits by antagonic bacteria to plant pathogens

– In this study was evaluated the efficacy of the bacterial strains: BB-4 ( Bacillus cereus GC, subgroup B), BS-2 ( Photorhabdus luminescens ), BB- 1 ( Bacillus alcalophilus ), BS-5 ( B. cereus GC, subgroup B), BB-5 ( Stenotrophomonas maltophilia ), BB-6 ( Yersinia bercovieri ) and BS-6 ( P. luminescens ) on the control of anthracnose in yellow passion fruit, on antagonism tests and fruits tests under laboratory conditions. The plant pathogen was grown in Petri dishes containing BDA medium for 15 days and the bacterial strains were multiplied in AN medium for two days at 28°C. In passion fruits test, a wound was performed at a depth of 2 mm, followed by spraying with a suspension containing a bacterial antagonist strain (10 8 cfu. mL -1 ). On the wound, a BDA disc with 4 mm in diameter completely colonized by the pathogen and maintenance for 7 days (25oC, high RU% and 12 hours of photoperiod) until the evaluation of diameter of lesions. The experimental design adopted was the completely randomized (9 treatments and 4 replications). The data were submitted to variance analysis and Tukey test (5%). In antagonism test, only BS-5 ( B. cereus GC, Subgroup B) and BS-2 ( P. luminescens ) strains did not inhibit the mycelial growth of the pathogen. The other strains were efficient in inhibition, with levels ranging from 35% to 53%, highlighting the strains BB-4 ( B. cereus GC. Sub group B), BS-3 ( P. luminescens ) and BB-4 ( S. maltophilia ), with 52.5%, 52.5% and 53.3% of control, respectively. In the fruit test, BS-2 ( P. luminescens ), BS-5 ( B. cereus GC, Subgroup B), BB-1 ( B. alcalophilus ), BS-3 ( P. luminescens ) and BB-6 ( Y. bercovieri ) inhibited the development of the pathogen, with control levels varying between 23.4% and 43.6%, with emphasis on BB-1 ( B. alcalophilus ) and BS-3 ( P. luminescens ), with 43.6% of control, indicating potential of use on the biocontrol of anthracnose on passion fruits.

English

English

A new record of Scleroconidioma sphagnicola isolated from soil in Korea

A fungal isolate, designated KNU-JJ-1824, was isolated from a soil sample collected from a field on Jeju, Korea. Colonies of the isolates cultured on PDA, MEA and CMAD for 14 days grew to diameters of 49~51 mm, 60~63 mm, and 47~50 mm, respectively. The colonies of this fungal isolate were dark green in color on both sides, and had irregular margins on the PDA media. Mycelia submerged and exhibited clear lines from the center to the edge on MEA media. On CMAD media, they were dark brown to greenish-brown, with narrow white margins. The shape of the conidia was guttulate, fusiform or clavate, and 1.9~3.4 × 6.5~10.2 μm in size. A molecular phylogenetic tree was constructed using dataset from small subunit (SSU) rDNA and the internal transcribed spacer (ITS) regions, and the isolate was found to cluster with Scleroconidioma sphagnicola UAMH 9731. Based on the results of the phylogenetic tree analysis and the cultural and morphological characteristics, the isolate was identified as Scleroconidioma sphagnicola. We report S. sphagnicola for the first time in Korea.

Regulatory mechanism underlying mycelium aggregation during filamentous fungi submerged fermentation

Filamentous fungi are one of the platforms for producing fermented products. The specific characteristic of their submerged fermentation is the aggregation of mycelia that is affected by environmental conditions, leading to significantly different rheology for fermentation broth. Such a rheological change not only affects the transfer of mass, heat and momentum, but also the biosynthesis of target products and the efficiency of their production. In this article, strategies for morphological regulation of filamentous fungi are reviewed, and the impact of calcium signal transduction and chitin biosynthesis on apical growth of hyphae and branching of mycelia for their aggregation are further commented.

Screening for antifungal activity of garlic (Allium sativum) powder against mycelia growth of three post-harvest pathogens

Screening for antifungal activity of garlic powder against mycelia growth of three post-harvest pathogens (Aspergillus, Rhizopus and Mucor species) was investigated in this study. Five grams of malt extract agar (MEA) were poured into a conical flask, 100 ml of water and different weight of garlic powder (1, 3, 5 and 7 g) were separately added, stirred and later sterilized while MEA medium with no garlic added (0 g) served as control. The mycelia of each post-harvest pathogen was cut with 6mm cork borer and placed on the solidified medium in the Petri dish and incubated at 28±2oC for 72 hours. Phytochemical screening of the garlic powder was also investigated. Results from this study showed that the different weights of the garlic powder apart from the control (0 g garlic) significantly inhibited the mycelia growth of the three post-harvest pathogens tested in the study and the order of antifungal activity of the garlic powder against mycelia growth of Aspergillus, Rhizopus and Mucor species was 7 g > 5 g > 3 g > 1 g > 0 g, 5 g > 7 g >1 g > 3 g > 0 g and 7 g > 5 g > 3 g > 1 g > 0 g respectively. The antifungal activity of the garlic powder may be related to the presence of active antimicrobial agents including alkaloids, saponins, tannins, flavonoids and cardiac glycosides that were detected in the powder. DOI: http://dx.doi.org/10.5281/zenodo.2635824

Changes in transcriptome expression profiles and functional analysis of differentially expressed genes during mycelium-to-yeast transformation of Sporothrix schenckii

Objective To compare and analyze the differences in the transcriptomics between mycelium and early yeast phases of Sporothrix schenckii (S. schenckii) , and to realize the changes in transcriptome expression profiles during mycelium-to-yeast transformation. Methods A standard strain of S. schenckii (ATCC 10268) was subjected to 96-hour culture with Sabouraud medium at 25 ℃ or 36-hour culture with brain-heart infusion medium at 37 ℃ to obtain the mycelium and yeast form of S. schenckii, and then, their transcriptomes were sequenced. Functional annotation was performed for screened unigenes by comparison using several databases (such as NR, Swiss-Prot, KEGG, COG, KOG, GO and Pfam) , coding sequence prediction, and gene expression analysis in each sample. Finally, the differentially expressed genes were subjected to pattern clustering, functional annotation and enrichment analysis. Results A total of 14.76 Gb valid data (clean data) were obtained, and functional annotation results were acquired in 28 094 of 43 863 assembled unigene clusters. Compared with S. schenckii in mycelium phase, there were 10 969 up-regulated genes and 199 down-regulated genes in S. schenckii in yeast phase. These differentially expressed genes were involved in protein phosphorylation, intracellular protein transport, cellular protein modification, small guanosine triphosphate-mediated signal transduction, vesicle-mediated transport, translation, intracellular signal transduction, microtubule formation, adenosine triphosphate synthesis, coupled proton transport and so on. Sixteen genes in the mitogen-activated protein kinase (MAPK) pathway and two-component signaling pathway, which were two important signal transduction pathways involved in fungal morphogenesis, and 16 genes involved in chitin synthesis and metabolism were all confirmed to be up-regulated in S. schenckii in yeast phase. Conclusions Compared with S. schenckii in mycelium phase, great changes in gene expression profiles were observed in S. schenckii in yeast phase. These differentially expressed genes are involved in many functions, suggesting that the dimorphic transition of S. schenckii is regulated by a multi-gene network system. Key words: Sporothrix; Hyphae; Transcriptome; Gene expression profiling; Differential gene expression analysis; Yeast phase

Manipulation of Plasma Dehydroepiandrosteron (DHEA) by Truffle and the Cultured Mycelium: BRM like Function of Truffles

Manipulation of Plasma Dehydroepiandrosteron (DHEA) by Truffle and the Cultured Mycelium: BRM like Function of Truffles

Obtaining vacuolar protein sorting 34 gene in Sporothrix globosa by RACE method and analysis of its expression during the mycelium-to-yeast transition

Objective To obtain the full-length sequence of the vacuolar protein sorting 34 coding gene (vps34) of Sporothrix globosa (S.globosa) and to investigate the role of vps34 gene during the phase transition from mycelium to yeast in S. globosa. Methods The 3′ end and 5′ end of the vps34 gene of S. globosa were amplified by rapid amplification of cDNA ends (RACE). The obtained sequences were spliced and analyzed by bioinformatics software. Quantitative reverse transcription PCR (qRT-PCR) was used to analyze the expression of vps34 gene in mycelial and yeast phases. Results The vps34 gene of S. globosa was 3 228 bp in length. The coding sequence was 3 000 bp and encoded 999 amino acids with a molecular mass of 111.49×103 and an isoelectric point of 6.38. It contained three domains including C2_PI3K_class_Ⅲ, PI3Ka_Ⅲ and PI3Kc_Ⅲ. The results of qRT-PCR showed that the expression of vps34 gene in yeast-phase S. globosa was higher than that in mycelial phase at 24 h (P<0.05), and the greatest difference between them was observed at 48 h (P<0.01). Conclusions Vps34p participates in the process of dimorphic transformation of S. globosa. The obtainment of the full-length vps34 gene of S. globosa lays the foundations for further study on the function of Vps34p. Key words: Sporothrix globosa; Sporotrichosis; Vacuolar protein sorting 34; Rapid amplification of cDNA ends; Quantitative reverse transcription PCR; Dimorphic transformation

Effect of variability and edaphological characteristics on growth of Sclerotium rolfsii (Sacc) causing collar rot disease of sunflower in coastal region of West Bengal, India

Sunflower is an important oilseed crop in India. One of the major diseases is collar rot caused by Sclerotium rolfsii (Sacc). This study was conducted during 2014–15 and 2015–16 under in-vitro condition. To see the effect of soil temperature and soil moisture, the S. rolfsii (Sacc). was grow at different temperature and at different moisture level. Results showed that among the different soil pH tested, pH5.7 was the best for colonization on wheat seeds 61.67% followed by 6.1(58.33%). In case of soil temperature most preferable temperature for mycelial grow of the pathogen was 30°C. The pathogen grown best in 30% soil moisture content followed by 25%. Variations were observed in colony morphology, mycelial growth, sclerotial size, colour and number of sclerotia. The number of sclerotia in different isolates varied from 352 (WBSR4) to 411 (WBSR9). Twenty five combinations showed compatible reaction out of 36 pairings in mycelial compatibility studies.

Changes in Nutritional Composition of Gryllus bimaculatus Fermented by Bacillus sp. and Mycelium of Basidiomycetes

Changes in Nutritional Composition of Gryllus bimaculatus Fermented by Bacillus sp. and Mycelium of Basidiomycetes

Suitable Conditions for Mycelial Culture of Tremella fuciformis

Suitable Conditions for Mycelial Culture of Tremella fuciformis

Sensitivity assessment of Phytophthora nicotianae to fungicides of fluazinam and its mixture with carboxylic acid amide

Tobacco black shank caused by Phytophthora parasitica var. nicotianae (Breda de Hean) is one of the most serious diseases in tobacco growing, and few effective fungicides are available currently. The purpose of this study was to assess the feasibility of using fluazinam to treat tobacco black shank disease. In vitro toxicities of fluazinam to 62 isolates of P. nicotianae were determined by mycelial growth rate method. The EC50 values ranged from 0.294 6 to 2.389 9 μg/mL with a mean of 1.084 0 μg/mL. The sensitivity distribution was unimodal, and there was no resistant isolate in P. nicotianae population. The carboxylic acid amide (CAA) fungicides were single-site in action and activity to oomycetes. The synergistic interactions were tested by Wadley method between fluazinam and dimethomorph, flumorph, mandipropamid, respectively. The mixture containing dimethomoph:fluazinam at 1:2 ratio showed additive actions, with the synergy ratio of 1.2. The mixture containing flumorph and fluazinam at 1:5 ratio had the highest synergy ratio (SR 2.07). Mandipropamid and fluazinam had an additive interaction and the proportion of 2:1 had the lowest EC50 value (0.020 7 μg/mL). This study demonstrated the sensitivity of P. nicotianae to fluazinam, and provided the experimental foundation to use fluazinam for tobacco black shank management.

Penicillifer diparietisporus: a New Record from Field Soil in Korea

A fungus was isolated from field soil collected from Daegu, Korea. The colony of the isolated fungus showed short, branched, and light to dark yellow pigments with hyaline, yellowish red to orange brown aerial mycelia. In addition, the fungus produced solitary to aggregated perithecia, ovoid to pyriform, short neck, and asci as well as biseriately arranged ascospores. Phylogenetic analysis using the internal transcribed spacer region and translation elongation factor 1-α sequences and morphological characteristics identified the isolated fungus as Penicillifer diparietisporus , which belongs to the family Nectriaceae. To our knowledge, this is the first report of Penicillifer diparietisporus in Korea.

Interacciones microbianas: Efecto de hongos biocontroladores y solubilizadores de fósforo en los estadios pre-simbióticos de hongos micorrícico arbusculares

El fósforo (P) es un macronutriente poco biodisponible para las plantas y por lo tanto, limitante para su crecimiento. El uso de hongos solubilizadores de P (HS) es una alternativa prometedora en el aprovechamiento de la fertilización fosforada. Sin embargo, aún no se ha establecido si los HS tienen efectossobre la micobiota benéfica del suelo, como los hongos micorrícico-arbusculares (HMA). Este trabajo estudia el efecto de HS con capacidad biocontroladora de fitopatógenos fúngicos sobre el desarrollo micorrícico preinfectivo de HMA, el primer paso en la colonización de la raíz, de los HMA. Se expusieron esporas del HMA Gigaspora rosea a distintas concentraciones de exudados (0; 0,01; 0,1; 1; 3%) de distintos HS: Talaromyces helicus cepa L7B, T. helicus cepa N24, T. diversus y Penicillium purpurogenum, en un sistema in vitro con medio semilíquido. Se evaluó la germinación de las esporas y la elongación, ramificación y morfología del micelio pre-infectivo. Se observó que solo T. diversus incrementó la germinación y que T. helicus L7B promovió la elongación, ramificación y modificó la morfología del micelio pre-infectivo del HMA sin afectarla germinación. Estos resultados demuestran que el desarrollo pre-infectivo de G. rosea (germinación, elongación, ramificación y morfología) puede ser modulado en función de la cepa de HS estudiada, sugiriendo que las interacciones microbianas podrían impactar positivamente sobre la nutrición fosforada vegetal mediante la modificación del estadio previo a la simbiosis micorrícica.

In vitro activity of some essential oils against Penicillium digitatum

Natural plant essential oils (EOs) can be used instead of synthetic fungicides because of human health concerns and environmental protection. In this study, the in vitro activity of some plants EOs against Penicillium digitatum, the cause of citrus green mold was evaluated during 8 days of incubation at 25°C. The EOs extracted from sweet orange ( Citrus sinensis) , lemon ( Citrus limon ), lime ( Citrus aurantifolia ), and sour orange ( Citrus aurantium ) fruit peel (500, 1000 and 2000 µl l-1 concentrations), cinnamon ( Cinnamomum cassia ) bark and summer savory ( Satureja hortensis ) aerial parts (400, 500 and 600 µl l-1 concentrations) were used on Penicillium digitatum mycelium. None of the EOs extracted from tested citrus in this study could inhibit mycelial growth completely even at concentration of 2000 µl l-1. The best results were obtained with cinnamon and summer savory EOs at concentration of 500 and 600 µl l-1. So, based on the results, cinnamon and summer savory EOs can be ideal candidates to replace the synthetic fungicides to control postharvest green mold of citrus fruit. GC-MS analysis showed that the most abundant of all constituents in EO extracts were carvacrol and γ-terpinene in summer savory and (E)-cinnamaldehyde in cinnamon.

Genetic diversity and infection sources of Rosellinia necatrix in northern Israel

Symptoms of white root rot (caused by Rosellinia necatrix ) of fruit trees (including apple, cherry and peach) are rotting of the roots and yellowing of the leaves, followed by wilting and death. Undecomposed organic material in forest soils is favourable for growth of R. necatrix . Genetic tools and mycelial compatibility assays can be used to group the fungus into genetically similar groups. This study identified and located the sources of root infection, using broad surveys of infested plots in various locations, and assessed infection probability as a function of distance from potential inoculum source. Fifty-five infested plots in 14 settlements at different altitudes were surveyed. About 60% of the infested plots, at altitudes up to 540 m above sea level, were located near Mediterranean oak maquis forests, and the infections spread inward from the edges of the fruit orchards. These results indicated four possible sources of infection: (i) Mediterranean maquis forest near agricultural lands; (ii) soil transferred to low-lying sections within orchards; (iii) infection source carried by farmers from plots on the same farm; and (iv) infections via roots of adjacent trees within orchards. No correlation was found between genetic variation and virulence, but isolates that grew quickly on potato dextrose agar plates at 28 o C were more virulent than slow growing isolates.