• Journal of Microbiology and Biotechnology
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• 제30권6호
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• pp.930-936
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• 2020

The red seaweed Gracilaria verrucosa has been used for the production of bioethanol. Pretreatment for monosaccharide production was carried out with 12% (w/v) G. verrucosa slurry and 500 mM HNO₃ at 121℃ for 90 min. Enzymatic hydrolysis was performed with a mixture of commercial enzymes (Cellic C-Tec 2 and Celluclast 1.5 L; 16 U/ml) at 50℃ and 150 rpm for 48 h. G. verrucosa was composed of 66.9% carbohydrates. In this study, 61.0 g/L monosaccharides were obtained from 120.0 g dw/l G. verrucosa. The fermentation inhibitors such as hydroxymethylfurfural (HMF), levulinic acid, and formic acid were produced during pretreatment. Activated carbon was used to remove HMF. Wild-type and adaptively evolved Saccharomyces cerevisiae, Candida lusitaniae, and Kluyveromyces marxianus were used for fermentation to evaluate ethanol production.

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.186-191
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• 2011

An agar-degrading enzyme-producing strain was isolated from seawater. The isolate was identified as Microbulbifer sp. SD-1 by 16S rRNA sequencing analysis. The optimal pH and temperature for growth were 6.0 and $30^{\circ}C$, respectively, and growth was possible at pH 9.0 and $60^{\circ}C$. The isolate required 5% NaCl for optimal growth and showed 45% growth activity without NaCl. Agar concentrations of 0-0.4% in the medium did not affect growth. Thin-layer chromatography analysis revealed that this strain could degrade agar into a monosaccharide and oligosaccharide, which may have industrial applications.

• 한국미생물·생명공학회지
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• 제17권6호
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• pp.533-538
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• 1989

S. uvarum KFCC 32021의 발효여액은 10% 농도에서 L. acidophilus KFCC 12731의 산생성 및 생육을 촉진하였으나 촉진작용은 10$0^{\circ}C$에서 10분간의 열처리에 의해 실활되었다. 또한 이 여액은 두유의 sucrose, raffinose 및 stachyose 등의 과당류를 분해하여 단당류의 함량을 증가시켰다. L. acidophilus KFCC 12731의 24시간 단독배양에서 두유의 단당류는 전량 소비되었으나 과당류는 거의 선량 잔존하였다. S. uvarum KFCC 32021의 단독배양에서는 단당류, sucrose 및 vaffinose는 완전 소비되었고, stachyose는 일부 잔존되고 manninotriose가 축적되었다. 혼합발효에서의 당소비유형은 S. uvarum의 단독배양에서와 유사하였다. 이상의 결과로 혼합배양에서 S. uvarum KFCC 32021은 두유의 과당류를 L. acidophilus KFCC 12731이 이용할 수 있는 단당류로 분해시켜 줌으로써 발효액의 산생성을 촉진시키는 것으로 보인다.

• Natural Product Sciences
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• 제10권1호
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• pp.35-39
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• 2004

Aldose reductase (AR), the key enzyme of the polyol pathway, is known to play important roles in the diabetic complications. The inhibitors of AR, therefore, would be potential agents for the prevention of diabetic complications. In order to clarify the structural requirements of flavonoids for aldose reductase inhibitory activity, thirty flavonoids were examined. Among the thirty flavonoids, flavonols such as quercetin (5), reyneutrin (7), quercitrin (9), isoquercitrin (11), and avicularin (14) were found to exhibit much stronger AR inhibition. Lonicerin (10), amentoflavone (27) and sophoraflavanone B (30) were also showed strong inhibitory activity. Especially, quercitrin and reyneutrin exhibited the most inhibitory potency on rat lens (RL) AR. The results suggested that flavonol having the 7-hydroxyl and/or catechol moiety at the B ring exhibit strong activity. In addition, flavonols having 3-O-monosaccharide also showed stronger inhibition than free flavonols at the 3-position. These results suggested that quercitrin and reyneutrin are attributed to be the promising compounds for the prevention and/or treatment of diabetic complications.

• 환경위생공학
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• 제24권1호
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• pp.40-46
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• 2009

The enzyme expressed from strain L-49 was 2.01 times higher than that of original strain. Strain L-49 can grow on culture plate with $50{\mu}g/mL$ ampicillin. The synthesis of $\alpha$-amylase was greatly suppressed when strain L-49 was grown on monosaccharide such as glucose and polysaccharide at the same time cell concentration was low. Amylase production was enhanced when the bacterium was grown on starch and dextrin. Among different nitrogen sources tried, yeast extract was found to be the best followed by panpeptone, peptone, meat extract, bean meal, and corn steep liquor. The average rate of enzyme production was enhanced for 3~4 times in fermentation time from 24h to 44h. The sugar uptake rate has also increased. Low oxygen supply rate enhanced the rate of strain propagation but depressed the enzyme production. Hence it is benefit to obtain high enzyme activity that agitation speed maintained not lower than 400r/min and aeration rate maintained greater than 1:1vvm.

• 한국미생물·생명공학회지
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• 제32권4호
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• pp.362-365
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• 2004

The fucoidan from Laminaria relicollected at Wando in Korea was purified with the yield of 2.3% in mass. The monosaccharide composiof the purified fucoidan was nearly identical to that of the commercial standard: fucose 63.71 %, xylose 22.98%, galactose 6.62%, mannose 0.24%, and uronic acid 3.26%. Microorganisms capable of degrading the purified fucoidan were isolated from the colonies on the minimal medium containing 0.2% of purified fucoidan as a sole carbon source. Of these isolates, a strain showing a relatively higher capability to degrade fucoidan, up to 63%, was partially characterized as a Gram positive, aerobic, moderately halophilic marine bacterium.

• Fisheries and Aquatic Sciences
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• 제22권11호
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• pp.24.1-24.7
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• 2019

Sporophylls from sea mustard, Undaria pinnatifida, which are by-products in seaweed production industries, were taken from Hansan Island, Tongyeong, and Gijang, Busan, and investigated for their fucoidan content and corresponding antioxidant activities. The extracted fucoidan yield from sporophylls of sea mustard samples from Tongyeong (TF) and Gijang (GF) were 12.1% and 13.6%, respectively. The antioxidant activities assessment of TF and GF extracts showed relative significant difference between samples, suggesting effect of location on bioactivities of fucoidan samples. GF was 50-68% more effective than TF against DPPH and superoxide radicals samples which may be attributed to the difference in their degree of sulfation and monosaccharide composition. Meanwhile, TF exhibited greater scavenging activity against hydroxyl radicals compared to GF which could be due to protein impurities.

• 한국식품과학회지
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• 제27권5호
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• pp.729-735
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• 1995

국내에서 생산되고 있는 4종류의 물엿에 대하여 $20^{\circ}C$와 $60^{\circ}C$의 온도에 저장중 품질 변화를 조사하였다. 저장 기간중 물엿의 색택은 흡광도, HMF 및 Hunter L 및 ${\Delta}E$ 값으로 측정하였을 때 모두 증가하였는데 전반적으로 저장 온도가 높고 가수분해 정도가 큰 물엿일수록 변색이 심하게 나타났다. 물엿은 모두 비뉴우턴 유체의 특성을 나타내었으며 저장중 악간의 증가만을 나타내었다. 그리고 저장기간중 물엿의 당조성은 단당류의 비율이 상대적으로 감소하고 이당류나 소당류의 비율이 약간 더 증가함을 알수 있었다.

• Journal of Microbiology and Biotechnology
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• 제30권11호
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• pp.1739-1749
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• 2020

Exopolysaccharide produced by the yeast Papiliotrema flavescens, isolated from wine grape berries of Champagne vineyard, was investigated for both chemical and functional characterization. SECMALLS and colorimetric assay analyses showed that the EPS is a high M_W heteropolymer (2.37 × 10⁶ g/mol) majorily consisting of mannose, glucose, xylose and glucuronic acid as monosaccharide constituents, with two substituents (sulphate and phosphate groups), and a minor protein moiety. Structural enchainment of these carbohydrates based on methylation, GC-MS and NMR analyses revealed a linear main backbone built up of α-(1 → 3)-D-mannopyranosyl residues on which are branched side chains consisting of a single β-D-glucopyranosyluronic acid residue and β-(1 → 2)-xylopyranoses (2-5 residues). Suggestion of some xylopyranose side chains containing a mannose residue at the nonreducing terminal end was also proposed. This is first report on EPSs from the grape P. flavescens yeast with such structural characteristics. Furthermore, investigations for valuating the application performance of these EPS in relation with their structural features were carried out in 8% alcohol experiment solutions. Very exceptional viscosifying and foaming properties were reported by comparison with commercial biopolymers such as Arabic, gellan and xanthan gums. The intrinsic properties of the natural biopolymer from this wild grape-associated P. flavescens yeast make it a potential candidate for use in various biotechnology applications.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.113-120
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• 1996

This study was conducted to understand the characteristics of fruit softening during ripening which causes deep loses in quality of horticultural products during storage and marketing process after harvest. The changes of cell wall components during ripening was investigated. The climacteric rise was between 42 and 49 days after anthesis and then decreased. Ethylene evolution was similar to respiration. The hardness of fruit decreased markedly at this climacteric period and significances of textural parameters among the ripening periods were recognized but the significance between 50 and 55 days after anthesis was not. Sugar components of cell wall polysaccharides were uronic acid, galactose, glucose, arabinose, xylose, rhamnose, mannose and fucose. The contents of arabinose and mannose in alcohol-insoluble solids fraction increased, but other sugars were not changed. In cell wall fraction, the contents of uronic acid, galactose, glucose and arabinose were comparatively high, but galactose, arabinose and ironic acid were decreased markedly during ripening. ironic acid occupied above 75% of total monosaccharide in pectin fraction and decreased markedly during ripening. In acid-soluble hemicellulose fraction, the contents of uronic acid, glucose, galactose and rhamnose were high and they decreased from 50 days after anthesis. The contents of glucose and xylose were high in a alkali-soluble hemicellulose fraction and they decreased markedly at 55days after anthesis.