• The Korean Journal of Mycology
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• v.51 no.3
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• pp.219-227
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• 2023

This study was conducted to analyze the distribution and characteristics of fungal species in meju using the traditional method. Fungal distribution in meju was investigated using metagenomic and morphological analyses, based on which Aspergillus flavus/oryzae strains were identified as the dominant fungi in all meju samples, followed by Pichia, Rhizopus and Lichtheimia spp. As A. flavus/oryzae was dominant, we further evaluated the aflatoxin production ability and enzymatic activity of the isolates. Thin-layer chromatography and polymerase chain reaction revealed that the A. flavus/oryzae strains isolated from meju are non-aflatoxigenic fungi. Based on the analyses of amylase and protease activities, strains with high activities of amylase or protease were identified, which are proposed to be used as starters for meju fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.208-213
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• 2007

The objective of the experiment was to determine the optimum cultural [moisture levels (55, 60 and 70%), days of fermentation (7, 14 and 21), temperature (25 and $35^{\circ}C$) of incubation)] and nutritional parameters (urea addition (0 and 2%) and variable levels of single super phosphate (0.25 and 0.50% SSP)) for bio-processing of the mustard (Brassica campestris) straw (MS) under solid-state fermentation (SSF) system. The performance of SSF was assessed in terms of favorable changes in cell wall constituents, protein content and in vitro DM digestibility of the MS. Sorghum based inoculum (seed culture) of Ganoderma lucidum to treat the MS was prepared. The 50 g DM of MS taken in autoclavable polypropylene bags was mixed with a pre-calculated amount of water and the particular nutrient in the straw to attained the desired levels of water and nutrient concentration in the substrate. A significant progressive increase in biodegradation of DM (p<0.001), NDF (p<0.01) and ADF (p<0.05) was observed with increasing levels of moisture. Among the cell wall constituents the loss of ADF fraction was greatest compared to that of NDF. The loss of DM increased progressively as the fermentation proceeded and maximum DM losses occurred at 28 days after incubation. The protein content of the treated MS samples increased linearly up to the day $21^{th}$ of the incubation and thereafter declined at day $28^{th}$, whereas the improvement in in vitro DM digestibility were apparent only up to the day $14^{th}$ of the incubation under SSF and there after it declined. The acid detergent lignin (ADL) degradation was slower during the first 7 days of SSF and thereafter increased progressively and maximum ADL losses were observed at the day $28^{th}$ of the SSF. The biodegradation of DM and ADL was not affected by the variation in incubation temperature. Addition of urea was found to have inhibitory effect on fungal growth. The effect of both the levels (0.25 and 0.50) of SSP addition in the substrate, on DM, NDF, ADF, cellulose and ADL biodegradation was similar. Similarly, the protein content and the in vitro DM digestibility remain unaffected affected due to variable levels of the SSP inclusion in the substrate. From the results it may be concluded that the incubation of MS with 60 percent moisture for 21 days at $35^{\circ}C$ with 0.25 percent SSP was most suitable for MS treatment with Ganoderma lucidum. Maximum delignification, enrichment in the protein content and improvement in in vitro DM digestibility were achieved by adopting this protocol of bioprocessing of MS.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.357-365
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• 1994

The effects of garlic concentrations on the properties of squid sik-hae such as the chemical and microbial changes were investigated. pH, the amounts of lactic acid showed significant differences at early stages of fermentation and no significant differences at later stages with increasing garlic concentrations. The amount of TMAO decreased with increasing storage periods and garlic concentrations, whereas that of TMA increased significantly at early stages of fermentation and showed no significant differences with increasing garlic concentrations. At later stages of fermentation, the amount of TMA at $2\%$ garlic concentration was higher than those at 3 and $4\%$. The number of lactic acid bacteria increased significantly garlic concentrations at early stages of storage and had no significant differences at later stages. The numbers of proteolytic bacteria, psychrotroph, and fungi increased in proportion to length of storage and garlic concentrations at early stages of storage whereas, the number of bacteria decreased significantly at later stages of storage with increasing garlic concentrations.

• Mycobiology
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• v.42 no.2
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• pp.189-192
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• 2014

During a search for neuraminidase inhibitors derived from medicinal fungi, we found that the fermentation broth of Phellinus linteus exhibited potent neuraminidase inhibitory activity. Through bioassay-guided fractionation, two active compounds were purified from the ethyl acetate-soluble portion of the fermentation broth of P. linteus. These structures were identified as inotilone (1) and 4-(3,4-dihydroxyphenyl)-3-buten-2-one (2) by spectroscopic methods. Compounds 1 and 2 inhibited H1N1 neuraminidase activity with $IC_{50}$ values of 29.1 and 125.6 $125.6{\mu}M$, respectively, in a dose-dependent manner. They also exhibited an antiviral effect in a viral cytopathic effect reduction assay using MDCK cells. These results suggest that compounds 1 and 2 from the culture broth of P. linteus would be good candidates for the prevention and therapeutic strategies towards viral infections.

• Mycobiology
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• v.44 no.3
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• pp.171-179
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• 2016

In the screening of marine mangrove derived fungi for lovastatin productivity, endophytic Aspergillus luchuensis MERV10 exhibited the highest lovastatin productivity (9.5 mg/gds) in solid state fermentation (SSF) using rice bran. Aspergillus luchuensis MERV10 was used as the parental strain in which to induce genetic variabilities after application of different mixtures as well as doses of mutagens followed by three successive rounds of genome shuffling. Four potent mutants, UN6, UN28, NE11, and NE23, with lovastatin productivity equal to 2.0-, 2.11-, 1.95-, and 2.11-fold higher than the parental strain, respectively, were applied for three rounds of genome shuffling as the initial mutants. Four hereditarily stable recombinants (F3/3, F3/7, F3/9, and F3/13) were obtained with lovastatin productivity equal to 50.8, 57.0, 49.7, and 51.0 mg/gds, respectively. Recombinant strain F3/7 yielded 57.0 mg/gds of lovastatin, which is 6-fold and 2.85-fold higher, respectively, than the initial parental strain and the highest mutants UN28 and NE23. It was therefore selected for the optimization of lovastatin production through improvement of SSF parameters. Lovastatin productivity was increased 32-fold through strain improvement methods, including mutations and three successive rounds of genome shuffling followed by optimizing SSF factors.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.184-192
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• 2006

Six-hundred bacterial strains from human milk and milk from Sahiwal cows, Holstein Friesian cows, and buffaloes were screened for their ability to suppress phytopathogenic fungi under in vitro conditions. A consortium of 3 strains, viz., Bacillus lentimorbus B-30486 (B-30486), B. subtilis B-30487 (B-30487), and B. lentimorbus B-30488 (B-30488), isolated from Sahiwal cow milk resulted in better biological control and plant-growth promotion than single-strain treatments. For commercial-scale production of a bioinoculant, the solid-state fermentation of sugarcane agro-industrial residues, i.e., molasses, press mud, and spent wash, using the consortium of B-30486, B-30487, and B-30488, resulted in a value-added product, useful for enhancing plant growth. The application of the consortium to sugarcane fields infested with Fusarium moniliforme and Colletotrichum falcatum resulted in a reduction of mortality and significantly higher (P=0.05) plant height, number of tillers, and cane girth when compared with the control. Furthermore, under field conditions, the treatment of sugarcane with the consortium resulted in significantly (P=0.05) greater plant growth compared with nonbacterized plants. Accordingly, this is the first report on the effective use of bacteria isolated from milk for biological control and enhancing plant growth under field conditions. Furthormore, a solid-state fermentation technology was developed that facilitates the economic utilization of agro-industrial residues for environmental conservation and improving plant and soil health.

• Journal of Microbiology and Biotechnology
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• v.23 no.7
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• pp.959-965
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• 2013

Monascus species have been used to produce fermented rice called Monascus-fermented rice (MFR). To improve a Monascus strain via activation of secondary metabolite (SM) gene clusters for use in the production of MFR, we overexpressed an ortholog of the laeA gene, which encodes a global positive regulator of secondary metabolism under the control of the strong heterologous Aspergillus nidulans alcA promoter in Monascus pilosus. The OE::laeA transformant produced more SMs, including those not detected under uninduced conditions. MFR produced using the M. pilosus OE::laeA strain contained 4 times more monacolin K, a cholesterol-lowering agent, than MFR produced using the wild-type strain. In addition, pigment production was remarkably increased, and the antioxidant activity was increased as well. The results from this study suggest that Monascus species, which are important industrial fermentative fungi in Asia, can be improved for the production of functional foods by overexpressing the laeA gene.

• Microbiology and Biotechnology Letters
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• v.15 no.6
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• pp.408-413
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• 1987

Microorganisms capable of degrading the raw naked barley were isolated from soil, and the amylase productivity of each strain was examined on plate contained 2％ raw naked barley. Of the fungi and actinomycetes tested, 71 strains were subjected to subsequent testing for amylase production, and 4 strains were selected as potent amylase producers. Among them, Strain No. 281 produced the most potent raw naked barley saccharifying enzyme, and was identified as genus Rhizopus from morphological and physiological studies. The ratio of raw starch saccharifying activity (RDA) of the crude enzyme derived from the Rhizopus sp. No. 281 was showed 2-3 fold higher than that of commercial enzyme when the raw naked barley was used as the substrate. In the case of uncooked alcohol fermentation using Rhizopus sp. No. 281 glucoamylase preparation, the alcohol yield of the broth was 2％ higher than that of the commercial enzyme.

• Korean journal of food and cookery science
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• v.31 no.1
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• pp.9-17
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• 2015

Shindari is a traditional fermented drink of Jeju in Korea, which is made with boiled barley and nuruk for short fermentation periods. This study determined chemical, microbiological, and sensory characteristics of the modified Shindari with 15% carrots as an additive (carrot Shindari), and this study compared it with a traditional Shindari as a control. After fermentation at $30^{\circ}C$ for a day, the pHs of the carrot Shindari and traditional Shindari largely decreased, and the total acidities increased in both of the Shindari. The significantly higher scores of Hunter's color values were observed more in carrot Shindari than in traditional Shindari. Also, carrot Shindari (0.4954 g/100 g) had a significantly higher content of vitamin C than traditional Shindari (0.0030 g/100 g). The most abundant free sugar and organic acid were glucose and lactic acid, respectively, in both of the Shindari. The total numbers of bacteria, fungi and lactic-acid bacteria in both samples increased by log 3 CFU/mL after fermentation. Based on 16S ribosomal RNA gene analysis, the dominant lactic-acid bacteria was Pediococcus acidilactici in both samples. The DPPH (1.1-diphenyl-2-picrylhydrazyl) radical scavenging activity of carrot Shindari (60.13%) was higher than that of traditional Shindari (23.70%). In sensory evaluations (taste, flavor, color, and overall acceptance), the carrot Shindari had higher scores in all these values. In this study, the modified Shindari with carrot presenting high sensory characteristic as well as chemical and microbiologic characteristics provide an opportunity to improve the application of a traditional fermented drink of Jeju, Shindari.

• Animal Bioscience
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• v.37 no.4
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• pp.655-667
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• 2024

Objective: This study aimed to assess the impact of a hydroethanolic extract of walnut green husks (WGH) on rumen fermentation and the diversity of bacteria, methanogenic archaea, and fungi in sheep fed a high-concentrate diet. Methods: Five healthy small-tailed Han ewes with permanent rumen fistula were selected and housed in individual pens. This study adopted a self-controlled and crossover design with a control period and an experimental period. During the control period, the animals were fed a basal diet (with a ratio of concentrate to roughage of 65:35), while during the treatment period, the animals were fed the basal diet supplemented with 0.5% hydroethanolic extract of WGH. Fermentation parameters, digestive enzyme activities, and microbial diversity in rumen fluid were analyzed. Results: Supplementation of hydroethanolic extract of WGH had no significant effect on feed intake, concentrations of total volatile fatty acids, isovalerate, ammonia nitrogen, and microbial protein (p>0.05). However, the ruminal pH, concentrations of acetate, butyrate and isobutyrate, the ratio of acetate to propionate, protozoa count, and the activities of filter paper cellulase and cellobiase were significantly increased (p<0.05), while concentrations of propionate and valerate were significantly decreased (p<0.05). Moreover, 16S rRNA gene sequencing revealed that the relative abundance of rumen bacteria Christensenellaceae R7 group, Saccharofermentans, and Ruminococcaceae NK4A214 group were significantly increased, while Ruminococcus gauvreauii group, Prevotella 7 were significantly decreased (p<0.05). The relative abundance of the fungus Pseudomonas significantly increased, while Basidiomycota, Fusarium, and Alternaria significantly decreased (p<0.05). However, there was no significant change in the community structure of methanogenic archaea. Conclusion: Supplementation of hydroethanolic extract of WGH to a high-concentrate diet improved the ruminal fermentation, altered the structure of ruminal bacterial and fungal communities, and exhibited beneficial effects in alleviating subacute rumen acidosis of sheep.