• Journal of Microbiology and Biotechnology
• /
• 제24권1호
• /
• pp.48-51
• /
• 2014

${\alpha}$-Neoagarooligosaccharide (${\alpha}$-NAOS) hydrolase was purified from Cellvibrio sp. OA-2007 by using chromatographic techniques after hydroxyapatite adsorption. The molecular masses of ${\alpha}$-NAOS hydrolase estimated using SDS-PAGE and gel filtration chromatography were 40 and 93 kDa, respectively, and the optimal temperature and pH for the enzyme activity were $32^{\circ}C$ and 7.0-7.2. ${\alpha}$-NAOS hydrolase lost 43% of its original activity when incubated at $35^{\circ}C$ for 30 min. The enzyme hydrolyzed neoagarobiose, neoagarotetraose, and neoagarohexaose to galactose, agarotriose, and agaropentaose, respectively, and produced 3,6-anhydro-L-galactose concomitantly; however, it did not degrade agarose.

• Journal of the Korean Society of Food Science and Nutrition
• /
• 제24권4호
• /
• pp.556-562
• /
• 1995

The $\alpha$-amylase inhibitor from naked barley was purified by DEAE-cellulose, Concanavalin-A sepharose and superose 6 column chromatography, and confirmed by capillary electrophoresis. The purified $\alpha$-amylase inhibitor showed a single band of 29KD in molecular weight when estimated by the SDS-PAGE. Its purity was increased by 12-fold as compared to its crude extract, and its specific activity was found to be 336.7units/mg. The major amino acids of the $\alpha$-amylase inhibitor from naked barley was appeared to be glutamic acid, asparitic acid and arginine. The inhibitor from naked barley was glycoproteins and carbohydrate content of inhibitor was 1.0%.

• Journal of Life Science
• /
• 제27권12호
• /
• pp.1403-1409
• /
• 2017

In this study, the xylitol dehydrogenase (XYL2) gene was expressed in Saccharomyces cerevisiae as a host cell for ease of use in the degradation of lignocellulosic biomass (xylose). To select suitable expression systems for the S.XYL2 gene from S. cerevisiae and the P.XYL2 gene from Pichia stipitis, $pGMF{\alpha}-S.XYL2$, $pGMF{\alpha}-P.XYL2$, $pAMF{\alpha}-S.XYL2$ and $pAMF{\alpha}-P.XYL2$ plasmids with the GAL10 promoter and ADH1 promoter, respectively, were constructed. The mating factor ${\alpha}$ ($MF{\alpha}$) signal sequence was also connected to each promoter to allow secretion. Each plasmid was transformed into S. cerevisiae $SEY2102{\Delta}trp1$ strain and the xylitol dehydrogenase activity was investigated. The GAL10 promoter proved more suitable than the ADH1 promoter for expression of the XYL2 gene, and the xylitol dehydrogenase activity from P. stipitis was twice that from S. cerevisiae. The xylitol dehydrogenase showed $NAD^+$-dependent activity and about 77% of the recombinant xylitol dehydrogenase was secreted into the periplasmic space of the $SEY2102{\Delta}trp1/pGMF{\alpha}-P.XYL2$ strain. The xylitol dehydrogenase activity was increased by up to 41% when a glucose/xylose mixture was supplied as a carbon source, rather than glucose alone. The expression system and culture conditions optimized in this study resulted in large amounts of xylitol dehydrogenase using S. cerevisiae as the host strain, indicating the potential of this expression system for use in bioethanol production and industrial applications.

• Culinary science and hospitality research
• /
• 제19권5호
• /
• pp.136-145
• /
• 2013

Currently many studies aimed at enhancing efficacy of medicinal food on biological activity using bioconversion technology including fermentation process. In this study, the quality characteristics and antioxidative activity of fermented Crataegi fructus was investigated. The antioxidant activity of fermented Crataegi Fructus was assessed by various radical scavenging assays using DPPH (2,2-Diphenyl-1-picrylhydrazyl), FRAP (Ferric ion reducing antioxidant power), Reducing power and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). Moisture content of fermented Crataegi Fructus was $39.3{\pm}0.06%$. Contents of crude ash, crude protein, and crude fat were $0.20{\pm}0.01$, $1.77{\pm}0.04$, and $1.40{\pm}0.59%$, respectively. Moreover, the hunter's color values of fermented Crataegi Fructus were 79.24 (lightnees), 1.58 (redness), and 31.25 (yellowness), respectively. Total phenolic contents of fermented Crataegi Fructus were $3,015{\pm}250$ GAE ${\mu}g/g$. The antioxidative activities of fermented Crataegi Fructus significantly increased in a dose dependent manner. In addition, fermented Crataegi Fructus slightly (10.4%) inhibited ${\alpha}$-glucosidase activity; however, there was no inhibitory activity against ${\alpha}$-amylase. In terms of proteolytic activity, fermented Crataegi Fructus showed a strong activity than pancreatin (used as a positive control). These results indicate that fermented Crataegi Fructus can be used as a natural resource for material aiding digestion.

• Journal of Life Science
• /
• 제24권6호
• /
• pp.633-641
• /
• 2014

This study investigated the antioxidant and antiobesity activity of extract powders from the following natural color resources: Polygonum indigo, Black locust, Cochineal, Catechu, Grape, Tesu flower, Henna, Chrysanthemum, Sandalwood Red, Himalayan Rhubarb, and Madder. Total phenol content was the highest in Catechu extract, at 348.25 mg/g. DPPH, ABTS radical scavenging activity and ferric reducing antioxidant power (FRAP) were also higher in Catechu extract. Bleaching inhibition activity in the ${\beta}$-carotene linoleic acid system was the highest in Black locust extract, as was ${\alpha}$-Glucosidase inhibition activity. ${\alpha}$-Amylase inhibition activity was the highest in Catechu extract. Trypsin inhibition activity of Black locust extract was greater than 60%, and ${\alpha}$- chymotrypsin inhibition activity of Catechu extract was greater than 40%. Lipase inhibition activity was the highest Black locust extract, at 52.73%. Viability of 3T3-L1 cells was not affected by treatment with extracts at concentrations of $1.25{\sim}25{\mu}g/ml$. Lipid accumulation in the 3T3-L1 cells was the lowest following treatment with Catechu extract, at 55.8%, and this extract also inhibited adipocyte differentiation. These results suggest that the Catechu and Black locust extracts have high antioxidant and antiobesity activities and can be useful ingredients in functional foods.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• 제14권1호
• /
• pp.209-225
• /
• 2001

Recently many efforts were focused to understand the mechanical insights of melanogenesis to develop the agents for hyper-pigmentation and hypo-pigmentation. In the melanin biosynthetic pathway, tyrosinase is the rate limiting enzyme, and ${\alpha}$-melanocyte stimulating hormone(MSH) or cAMP-elevating agents stimulate melanogenesis and enhance the melanin synthesis and the tyrosinase activity. The author has analyzed the effects of Radix Trichosanthis on the basal melanogenic activities of B16/F10 mouse melanoma cells, and on the ${\alpha}$-MSH or forskolin-induced melanogenesis. Radix Trichosanthis alone markedly suppressed melanin content and tyrosinase activity in a dose-dependent manner. Pretreatment of the cells with Radix Trichosanthis also suppressed the increase of ${\alpha}$-MSH (10 nM) or forskolin (20${\mu}M$)-induced melanin content and tyrosinase activity. The decrease in the tyrosinase activity was paralled by a decrease in the abundance of tyrosinase protein and tyrosinase promoter activity. Pretreatment of the cells with Radix Trichosanthis also inhibited the increase of forskolin($20{\mu}M$) induced the amount of tyrosinase protein and tyrosinase promoter activity. The results of DOPA staining revealed that pretreatment of the cells with Radix Trichosanthis showed less intensity than B16 melanoma cells stimulated with ${\alpha}$- MSH or forskolin. These results suggest that Radix Trichosanthis inhibits melanogenesis and abrogates ${\alpha}-MSH and cAMP-induced melanogenesis in B16 melanoma cells.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• 제17권1호
• /
• pp.82-93
• /
• 2004

Recently many efforts were focused to understanding the mechanical insights of melanogenesis to develop the agents for hyper-pigmentation and hypo-pigmentation. In the melanin biosynthetic pathway, tyrosinase is the rate limiting enzyme, and ${\alpha}$-melanocyte stimulating hormone(MSH) or cAMP-elevating agents stimulate melanogenesis and enhance the melanin synthesis and the tyrosinase activity. The author has analyzed the effects of Radix Trichosanthis on the basal Melanogenic activities of Bl6/F10 mouse melanoma cells, and on the ${\alpha}$-MSH or forskolin-induced melanogenesis. Radix Trichosanthis alone markedly suppressed melanin content and tyrosinase activity in a dose-dependent manner. Pretreatment of the cells with Radix Trichosanthis also suppressed the increase of ${\alpha}$-MSH(10 nM) or forskolin(20 ${\mu}$M)-induced melanin content and tyrosinase activity. The decrease in the tyrosinase activity was paralled by a decrease in the abundance of tyrosinase protein and tyrosinase promoter activity. Pretreatment of the cells with Radix Trichosanthis also inhibited the increase of forskolin(20 ${\mu}$M) induced the amount of tyrosinase protein and tyrosinase promoter activity. The results of DOPA staining revealed that pretreatment of the cells with Radix Trichosanthis showed less intensity than B16 melanoma cells stimulated with ${\alpha}$-MSH or forskolin. These results suggest that Radix Trichosanthis inhibits melanogenesis and abrogates ${\alpha}$-MSH and cAMP-induced melanogenesis in B16 melanoma cells.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• 제16권3호
• /
• pp.129-144
• /
• 2003

Recently many efforts were focused to understand the mechanical insights of melanogenesis to develop the agents for hyper-pigmentation and hypo-pigmentation. In the melanin biosynthetic pathway, tyrosinase is the rate limiting enzyme, and ${\alpha}$-melanocyte stimulating hormone(MSH) or cAMP-elevating agents stimulate melanogenesis and enhance the melanin synthesis and the tyrosinase activity. The author has analyzed the effects of Rhizoma Bletillae on the basal melanogenic activities of B16／F10 mouse melanoma cells, and on the ${\alpha}$-MSH or forskolin-induced melanogenesis. Rhizoma Bletillae alone markedly suppressed melanin content and tyrosinase activity in a dose-dependent manner. Pretreatment of the cells with Rhizoma Bletillae also suppressed the increase of ${\alpha}$-MSH (100 nM) or forskolin (20 ${\mu}M$)-induced melanin content and tyrosinase activity. The decrease in the tyrosinase activity was paralled by a decrease in the abundance of tyrosinase protein and tyrosinase promoter activity. Pretreatment of the cells with Rhizoma Bletillae also inhibited the increase of forskolin(20${\mu}M$) induced the amount of tyrosinase protein and tyrosinase promoter activity. The results of DOPA staining revealed that pretreatment of the cells with Rhizoma Bletillae showed less intensity than B16 melanoma cells stimulated with ${\alpha}$-MSH or forskolin. These results suggest that Rhizoma Bletillae inhibits melanogenesis and abrogates ${\alpha}$-MSH and cAMP-induced melanogenesis in B16 melanoma cells.

• Korean Journal of Food Science and Technology
• /
• 제37권3호
• /
• pp.474-478
• /
• 2005

Antioxidative effects of several solvents extracts of cactus Cheonnyuncho (Opuntia humifusa) grown in Korea were investigated. Because 70% ethanol extract showed relatively high antioxidative activity and extraction yield, it was sequentially fractionated with hexane, chloroform, ethyl acetate, butanol, and water, Ethyl acetate fraction showed highest scavenging activity against free radical DPPH. Antioxidative activity of ethyl acetate fraction determined based on acid and peroxide values under accelerated oxidation condition of lard was similar to that of ${\alpha}$-tocopherol, but slightly lower than that of BHA. Similar results were observed using TBA method during peroxidation of linoleic acid.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• 제24권1호
• /
• pp.25-35
• /
• 2011

Objective : The present study was designed to assess the potential inhibitory activity of an ethanol extract of Belamcandae Rhizoma (EBR) on the alpha-melanocyte stimulating hormone (${\alpha}$-MSH)-induced melanogenesis signal pathway in B16F10 melanoma cells. Methods : Several experiments were performed in B16F10 melanoma cells. We studied tyrosinase activity, melanin content, cell-free tyrosinase activity and DOPA stain, and performed Western blots and RT-PCR for proteins and mRNA involved in melanogenesis. Results : ${\alpha}$-MSH-induced tyrosinase activity and melanin content were inhibited significantly by EBR. EBR markedly suppressed the protein expression level of tyrosinase in B16F10 melanoma cells. On the other hand, the expression of tyrosinase-related protein-1 (TRP-1) and -2 (TRP-2; DCT) were not affected by EBR. To elucidate the mechanism of the depigmenting property of EBR, we examined the involvement EBR in cAMP response element binding (CREB) protein phosphorylation and microphthalmia-associated transcription factor (MITF) signalling induced by ${\alpha}$-MSH. EBR did not regulate CREB phosphorylation and MITF expression by ${\alpha}$-MSH. Nevertheless, the mRNA expression of tyrosinase was significantly attenuated by EBR treatment without changes in the expression of TRP-1 and -2 mRNA. Conclusion : Our study suggested that EBR inhibits ${\alpha}$-MSH-induced melanogenesis by suppressing tyrosinase mRNA.