• Korean Journal of Food Science and Technology
• /
• v.14 no.1
• /
• pp.57-62
• /
• 1982

The possibility of developing new kinds of lactic acid beverage from a malt syrup was studied. The optimum sugar concentration of malt syrup for the cultivation of lactic acid bacteria was $10^{\circ}Bx$. The acidity of the fermented malt syrup was improved by the supplement of yeast extract(0.5%) or sodium citrate(0.08%). Though the activity of Lactobacillus lactis in malt syrup was superior to other strains, sensory test indicated that the mixed culture of Lactobacillus lactis and Streptococcus diacetilactis was better because of masking malt flavour. The changes in acidity and viable cells of malt syrup during the lactic fermentation were not so good as skim milk medium, but malt syrup medium containing milk(50 : 50) was nearly similar to skim milk medium. In the sensory scores among samples, no significant differences(P<0.05) were noted between fermented milk and fermented malt syrup containing milk, but fermented malt syrup showed a poor quality. However fermented malt syrup was not inferior to marketing lactic fermented fruit juices with regards to the lactic acid fermented beverage type.

• 한국균학회소식:학술대회논문집
• /
• 2018.05a
• /
• pp.29-29
• /
• 2018

Sparassis latifolia is called "Cauliflower Mushroom" and is known as an edible mushroom that has high content of ${\beta}$-glucan. Recently, artificial cultivation of S. latifolia has been done by bottle, plastic bag and wood cultivation in Korea. However it is not widely used because there are low incubation ratio and yield. For the high efficiency of production, we aim to find the superior strains and media for better mycelial and fruit body growth. First, we analyzed the genetic relationship among 31 strains and divided five groups with three kinds of URP primers. And then ten strains were selected from five groups based on the experiment of mycelial growth. The suitability of media for mycelial growth was different according to media type. The suitable solid and liquid media for mycelial growth of S. latifolia isolates were PDA and M2, respectively. In addition, with regard to C/N ratio, the mycelial growth increased even until C/N 160. Second, we investigated the production of fruitbody of the strains by plastic bag cultivation. The substrate was mixed with larch sawdust, corn flour, and wheat flour (8:1:1, v/v). Moisture content of substrate was controlled by about 60% with 10% molasses solution. Out of 31 strains, 19 strains formed primordia. The eight strains produced more than 140g/1kg in fresh weight. Third, molasses culture media was selected for the mycelial growth. And molasses suitable sugar content and input aeration were around 8Brix% and 0.3~0.6vvm, respectively. The longer the incubation period is, the more dried weight of mycelia increased, but medium volume decreased. Therefore, the best incubation period was 9 to 11 days depending on strains. In the future, research project entitled development of culture system and new variety for stable production of S. latifolia will be considered as a new item.

• Microbiology and Biotechnology Letters
• /
• v.43 no.1
• /
• pp.9-15
• /
• 2015

The seaweed, Gracilaria verrucosa, was fermented to produce bioethanol. Optimal pretreatment conditions were determined to be 12% (w/v) seaweed slurry and 270 mM sulfuric acid at 121℃ for 60 min. After thermal acid hydrolysis, enzymatic saccharification was carried out with 16 U/ml of mixed enzymes using Viscozyme L and Celluclast 1.5 L to G. verrucosa hydrolysates. A total monosaccharide concentration of 50.4 g/l, representing 84.2% conversion of 60 g/l total carbohydrate from 120 g dw/l G. verrucosa slurry was obtained by thermal acid hydrolysis and enzymatic saccharification. G. verrucosa hydrolysate was used as the substrate for ethanol production by separate hydrolysis and fermentation (SHF). Ethanol production by Candida lusitaniae ATCC 42720 acclimated to high-galactose concentrations was 22.0 g/l with ethanol yield (Y_EtOH) of 0.43. Acclimated yeast to high concentrations of specific sugar could utilize mixed sugars, resulting in higher ethanol yields in the seaweed hydrolysates medium.

• Applied Biological Chemistry
• /
• v.27
• /
• pp.29-46
• /
• 1984

To utilize several species of hard wood as raw materials of feed products, fermentation characteristics of cellulosic substrates to single cell protein was investigated, and results were summarized as follows. Among the microorganisms investigated, Tricoderma viride was selected as one of the most cellulolytic. Mixed culture of fungi did not show a synergistic effect on cellulose degradation. When the fungi were cultured at $28^{\circ}C$ for 7 days in a medium containing wheat bran 25 g, cellulose 0.25 g, proteose peptone 0.025 g and tween 800.025 g, cellulotic activities on carboxy methyl cellulose and filter paper reached maximum at 12 hr. The alkali treatment resulted in increased degradation of substrate from 13 to 18% when treated with enzymes for 12h, and reducing sugar formation increased with decreased size of substrates. Glucose was a very good feedback inhibitor of the enzyme from T.viride than that of xylose. When the substrate was rehydrolyzed, hydrolysis rate was 31% to reducing sugars within 12 hr. Quantative anlysis with HPLC showed the ratio of glucose to xylose in sugar syrups as 1.77 to 1. For the purpose of producing cellulosic-single cell protein from the sawdust of mulberry tree, 15 strains of xylose-assimilating yeast were isolated from 42 samples of rotten woods and compost soils and examined for their ability to utilize xylose. Then three strains were selected by their strong xylose-assimilating activities. The cultivative condition, the growth characteristics, and protein and nucleic acid productivities of three strains were investigated. The results obtained were, 1. Wood hydrolysate of mulberry tree was assimilated by 5 strains of CHS-2, CHS-3, ST-40, CHS-12 and CHS-13. 2. The optimum initial pH and temperature for the growth of strain CHS-13 were 4.4 and $30^{\circ}C$. 3. The specific growth rate of strain CHS-13 was $0.23h^{-1}$ and generation time was 3.01 hrs at the optimum condition. 4. CHS-13 strain assimilated 81 % of sugar in wood hydrolysate. 5. CHS-13 strain was identified as Candida guilliermondii var. guilliermondii 6. When the CHS-13 strain was cultured in the wood hydrolysate containing yeast extract, L-protein content was increased with yeast extract concentration. 7. The L-protein and nucleic acid yields from wood hydrolysate were 0.73 mg/ml and $4.92{\times}10^{-2}\;mg/ml$ respectively. 8. An optimal nucleic acid content of CHS-13 strain was observed in the medium containing 0.2% of yeast extract.

• The Korean Journal of Mycology
• /
• v.36 no.1
• /
• pp.58-62
• /
• 2008

'Miso', a new variety of oyster mushroom was developed for the bottle culture at the Chungnam Agricultural Research & Extension Services. Its mycelium grew rapidly with $8.4{\sim}8.6\;mm/day $ at $25{\sim}28^{\circ}C$ on PDA medium. The optimum pH of the mycelial growth was pH 5.0. It took 24 days for the primitive primordium formation after inoculation on pine sawdust media mixed with 20% wheat bran. Fruiting body color was white, and the shape of pileus was convex-umbonate. In the bottle culture, the yield was 115.7 g per 850 ml bottle. Stipe length was about 54 mm, the number of stipe per bottle was 18.1, the size of pileus was 28 mm, and gill was crowded. The moisture content of 'Miso' was lower than that of Jangan No.5 and Wonhyeong No.1, and contents of protein, ash and sugar of 'Miso' were higher than those of other varieties, and tannin acid content of 'Miso' was lower than that of others. On the basis of AFLP analysis, the 'Miso' was distinct not only from Wonhyeong No.1, but also from their closest relative, oyster mushrooms.