• Food Science and Preservation
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• v.9 no.1
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• pp.28-35
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• 2002

This study was conducted to evaluate the quality characteristics of different soy sauces. The soybean sauces brewed tty the A. oryzae koji(SAO), M. pilosus-1 koji(SMP) and the mixture of 50% M. pilosus-1 koji(SAM) during 90 days fermentation. Total nitrogen contents of the SAM, SAP and SMP were 13.6%, 1.15% and 1.22%, respectively. Content of amino type nitrogen in SAM was 0.78%, and the content was higher than those of SAO and SMP. Total free amino acid contents of SAO, SMP and SAM were 533.8, 732.4 and 807.3 mg/100 mL. The highest contents of free, amino acids were glutamic acid(65.20 mg/100 mL) in SAG, alanine(101.42 mg/100mL) in SMP, glutamic acid(130.52 mg/100 mL) in SAM. The highest activities of pretense and ${\beta}$-amylase showed in SAM, and the lowest activities of ${\alpha}$-amylase and glucoamylase were in SAO and SMP respectively. Hue angle values showed 56.3 in SAO, 29.0 in SMP and 32.2 in SAM. Monacolin K contents, as inhibitor of cholesterol bio-synthesis were 6.21 $\mu\textrm{g}$/mL for SMP and 3.10 $\mu\textrm{g}$/mL for SAM, and the inhibitory activities of SMP ane SAM aginst HMG-CoA reductase were 21.5 md 10.2%, respectively. Sensory scores for color, flavor, savory taste and overall taste of SAM was higher than those of SAO and SMP.

• Food Science of Animal Resources
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• v.29 no.6
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• pp.659-667
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• 2009

Casein is considered to be the main source of protein in milk; therefore, many studies have been conducted to identify casein-derived bioactive peptides and their physiological effects. Casein is inactive within the parent protein but can be liberated by various proteases and enzymatic hydrolysis during microbial fermentation and gastrointestinal digestion. Once absorbed, casein exhibits different bioavailabilities in the body. Specifically, casein-derived peptides function as angiotensin converting enzyme (ACE) inhibitor in the cardiovascular system; thus, they are expected to reduce and prevent hypertension. Additionally, casein-derived peptides behave as opioid-like peptides in the nervous system, which impacts relaxation. These peptides are also expected to modulate various aspects of immune functions. Finally, caseinophosphopeptide (CPP) and glycomacropeptide (GMP) may exhibit a number of nutritional effects such as the absorption of calcium, iron or zinc. Many studies have been conducted to evaluate casein-derived peptides due to their multifunctional properties and the results of these studies have contributed to the development of a wide variety of functional dairy products. The purpose of this paper was to review the generation of bioactive peptides, their absorption and metabolism, and their specific bioactive effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.34 no.6
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• pp.326-333
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• 2020

Nitrate-nitrite-nitric oxide (NO) pathway is a major alternative source of NO and is essential for NO - dependent physiological functions in body. Food supplements having nitrate/nitrite can improve metabolic syndromes including hypertension through antioxidant activity or vasodilation. The purpose of this study was to observe the effects of fermented garlic (F. garlic) having high concentration of NO2- on changes in blood flow and nitric oxide synthesis in the cerebral cortex of rodents. The generation of nitric oxide detected by a chemi-luminescence detector was higher in F. Garlic compared with NaNO2 solution under artificial gastric juice with pH 2.0. Ether F. garlic or NaNO2 diluted with artificial cerebrospinal fluid was directly applied into around the needle probe of laser Doppler flow meter that was located on epidural surface of the cortex. Direct application of F. garlic resulted in increase of cerebral blood flow detected by a laser Doppler flow meter with a dose-dependent manner. Compared with NaNO2 solution, F. garlic produced changes in cerebral blood flow at lower concentration of NO2-. Pretreatment of methylene blue, a guanylyl cyclase inhibitor prevented upregulation of cerebral blood flow by the treatment of F. garlic. In addition, the application of F. garlic with 250, 500ppm of NO2- caused significantly the production of NO in the cortical tissue but NaNO2 solution with 500ppm of NO2- did not. In summary, these results suggested that F. garlic with high content of NO2- induce increase in cerebral blood flow through nitric oxide-dependent signal pathway.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.213-219
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• 1972

In order to utilize sweet potatoes for the material of Takju, brewing experiments with raw sweet potatoes, sweet potato chips powder and its koji were conducted; and various tests were carried out on effect of the treatments of acid, alkali, polyphenol oxidase inhibitor, oxidizing and reducing agents upon the prevention against coloring of sweet potato chips by steaming, and on peeling effect of sweet potatoes by the alkali and heat treatments. The results obtained were as follows. 1) In the case of brewing with raw sweet potatose, each plot showed low acid and ethanol content, and its finished Takju had an undersirable color and odor. The plots which were mashed after peeling showed higher ethanol contents than the plots mashed without peeling. 2) In the case of brewing with sweet potato chips powder, each plot contained considerably more amount of ethanol than the plots brewed with raw sweet potatoes, white it contained less amount of acid. The ethanol contents of the plots using wheat bran koji were $10.5{\sim}11.4$ per cent 4 days after mashing, and were higher than those of the plots using malts powder. Their finished Takju was inferior in quality because of the lack of acid and being darkened gradually in process of time. 3) The kojies which were made of sweet potato chips powder with Neurospora sitophila or Aspergillus oryzae had good appearance, but the Takju mashes brewed with these contained remarkably less amount of ethanol. 4) Effect of the treatments of acid, alkali, polyphenol oxidase inhibitor and organic solvents such as ether and ethanol upon the prevention against coloring of sweet potato chips was not recognized. Alum and burnt alum were effective a little on the decolorization, and among the oxidizing and reducing agents tested, potassium permanganate was most effective. 5) Darkening of sweet potato chips powder in course of heating after mixing with water was not affected by pectin and amino acids, but by tannin. 6) Sweet potatoes were not peeled easily by friction after soaking in the boiling solution of 3 per cent alkali for 6 minutes and peeled in boiling water for 12 minutes. From the viewpoint of the results above mentioned, it seems to be necessary to study further on the isolation of microorganisms which are able to decompose the coloring substances and yeasts which are adequate for the fermentation of sweet potatoes in order to utilize sweet potatoes for Takju brewing, because brewing with raw sweet potatoes, sweet potato chips powder and its koji was unsuccessful, and effect of the various treatments on the decolorization of sweet potatoes was not recognized.

• Korean Journal of Microbiology
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• v.41 no.3
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• pp.225-231
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• 2005

The characteristics of cell growth and medium-chain-length polyhydroxyalkanoate (MCL-PHA) biosynthesis of Pseudomonas chlororaphis HS21 were investigated using plant oils as the carbon substrate. The organism was efficiently capable of utilizing plant oils, such as palm oil, corn oil, and sunflower oil, as the sole carbon source for growth and MCL-PHA production. When palm oil (5 g/L) was used as the carbon source, the cell growth and MCL-PHA accumulation of this organism occurred simultaneously, and a high dry cell weight (2.4 g/L) and MCL-PHA ($40.2\;mol{\%}$ of dry cell weight) was achieved after 30 hr of batch-fermentation. The repeating unit in the MCL-PHA produced from palm oil composed of 3-hydroxyhexanoate ($7.0\;mol{\%}$), 3-hydroxyoctanoate ($45.3\;mol{\%}$), 3-hydroxydecanoate ($39.0\;mol{\%}$), 3-hydroxydodecanoate ($6.8\;mol{\%}$), and 3-hydroxytetradecanoate ($1.9\;mol{\%}$), as determined by GC/MS. Even though glucose was a carbon substrate that support cell growth but not PHA production, the conversion rate of palm oil to PHA was significantly increased when glucose was fed as a cosubstrate, suggesting that bioconversion of some functionalized carbon substrates to related polymers in P chlororaphis HS21 could be enhanced by the co-feed of good carbon substrates for cell growth. In addition, the change of compositions of repeating units in MCL-PHAs synthesized from the plant oils was markedly affected by the supplementation of acrylic acid, an inhibitor of fatty acid ${\beta}-oxidation$. The addition of acrylic acid resulted in the increase of longer chain-length repeating units, such as 3-hydroxydodecanoate and 3-hydroxytetradecanoate, in the MCL-PHAs produced. Particularly, MCI-PHAs containing high amounts of unsaturated repeating units could be produced when sunflower oil and corn oil were used as the carbon substrate. These results suggested that the alteration of PHA synthesis pathway by acrylic acid addition can offer the opportunity to design new functional MCL-PHAs and other unusual polyesters that have unique physico-chemical properties.

• KSBB Journal
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• v.24 no.5
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• pp.439-445
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• 2009

The process for ethanol production requires lignocellulosic biomass to be hydrolyzed to generate monomeric sugars for the fermentation. During hydrolysis step, a monomeric sugars and a broad range of inhibitory compounds (furan derivatives, weak acids, phenolics) are formed and released. In this study, we investigated the effects of inhibitory compounds on the fermentative performance of Saccharomyces cerevisiae K35 and Pichia stipitis KCCM 12009 in ethanol production, two yeast strains were fermented in the synthetic medium including six inhibitory compounds such as 5-hydroxymethylfurfura (5-HMF), furfural, acetic acid, syringaldehyde, vanillic acid and syringic acid. Ethanol of over 40 g/L was produced by two yeast strains in the absence of inhibitory compounds, respectively. Most inhibitory compounds except acetic acid had a little effect on the ethanol production, but acetic acid showed high inhibition effect on the cell growth and ethanol production.

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