• Food Science and Preservation
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• v.31 no.1
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• pp.138-148
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• 2024

The production of poly-γ-glutamic acid (γ-PGA) and γ-aminobutyric acid (GABA) was optimized by serial fermentation of Dendropanax morbiferus extract (DME) using Bacillus subtilis HA and Lactobacillus plantarum KS2020. The 1st alkaline fermentation was performed on 60% DME including 2% glucose and 10% monosodium ʟ-glutamate (MSG) as a precursor. The 1^st fermented DME had 57 mg% tyrosine. Consequently, the 2^nd lactic acid fermentation for 5 days increased the tyrosine content of 106 mg%. The mucilage containing γ-PGA showed a high content of 3.50% on the first day of alkaline fermentation and then increased to 4.10% after 2 days. The precursor (MSG) remaining in the 1^st fermented DME was efficiently converted to GABA by the 2^nd lactic acid fermentation in the presence of 5% skim milk, 1.5% glucose and 0.5% yeast extract, resulting in the production of 18.29 mg/mL GABA. The viable cells of lactic acid bacteria increased and indicated 9.49 log CFU/mL on the fermentation for 5 days, and the acidity of co-fermented DME indicated the highest value of 1.55%. Conclusively, the serial fermented DME has multi-functional ingredients containing γ-PGA, GABA, peptides and probiotics.

• Journal of Life Science
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• v.21 no.2
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• pp.309-315
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• 2011

Rice syrup meal (RSM) was enzymatically hydrolyzed using eight commercial proteases (Protamex, Neutrase, Flavourzyme, Alcalase, Protease M, Protease N, Protease A, Molsin F) for 4 hr at optimum pH and temperature. Proteolytic hydrolysates were examined in supernatant and precipitate using Lowry protein assay, semimicro Kjeldahl method and gravimetric method using weight difference before and after enzymatic hydrolysis. Although RSM contains a high amount of protein (71.2%), only a very small amount of protein was hydrolyzed. Two proteases (Protease M and Protease N) were found to be the most effective in the hydrolysis of RSM protein. In Lowry method, 57.5 and 59.0 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments, respectively. In gravimetric method, 80.0 and 85.4 mg protein/g RSM were hydrolyzed after Protease M and Protease N treatments. In Kjeldahl method, 67.43 and 70.43 mg protein/g RSM were hydrolyzed after Protamex and Protease N treatments, respectively. For synergistic effect, two or three effective commercial proteases (Protease M, Protease N and Protease A) were applied to RSM at one time. The highest hydrolysis of RSM protein was observed in both Lowry protein assay (80.3 mg protein/g RSM) and gravimetric methods (153.2 mg protein/g RSM) when three commercial proteases were applied at one time, suggesting the synergistic effect of those proteases.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.323-330
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• 1998

Cyclodextrin glucanotransferase (CGTase) was purified from the culture broth of the Bacillus firmus var. alkalophilus, using ultrafiltration, starch adsorption/desorption, ion-exchange chromatography on DEAE-cellulose and gel filtration on Sephacryl HR-100. The molecular weight of the purified enzyme was determined as 77,000 by SDS-PAGE. The optimum pH and temperature for the CD synthesis were 6.0 and 5$0^{\circ}C$, respectively. The activity of this enzyme was stably kept at the range of pH 6.0～9.5 and up to 5$0^{\circ}C$. However, in the presence of $Ca^{2+}$, the optimum temperature for CD synthesis was shifted 55~6$0^{\circ}C$ and this enzyme was stable up to 6$0^{\circ}C$ because of the stabilizing effect of $Ca^{2+}$. The purified CGTase produced CDs with high conversion yields of 45~51% from sweet potato starch, com starch and amylopectin as substrate, especially, and the product ratio of $\beta$-CD to ${\gamma}$-CD was obtained at range of from 5.8:1 to 8.4:1 according to the kind of substrate. The purified enzyme produced mainly $\beta$-CD without accumulation of $\alpha$-CD during enzyme reaction using various starches as the substrate, indicating that the purified enzyme is the typical $\beta$-CGTase. The purified CGTase produced 25 g/l of CDs from 5.0% (w/v) liquefied com starch and the conversion yield of CDs was 50%, and the content of $\beta$-CD was 84% of total CDs after 8 hours under the optimum reaction condition.ion.

• Biomedical Science Letters
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• v.1 no.1
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• pp.55-72
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• 1995

Forty gentamicin-resistant isolates of Enterococcus faecalis were selected from various clinical materials, determined their antimicrobial susceptibility, and studied there R-plasmid characteristics and polypeptide patterns. All of the isolates were susceptible to vancomycin. The MICs($\mu$/ml) of antimicrobial agents to the isolates were as follows; the MIC of gentamicin was 128 and $\geq$2040, ampicillin 1 and 1, chlorarmphenicol 2 and 8, erythromycin 32 and 256, and vancomycin 1 and 2. E. faecalis HL-1 strain had 8 plasmid DNA elements, HL-2 and HL-3 strains had 6, HL-4 had 7, HL-5 had 4, and HL-6 had 5. The 51.7 Kb of gentamicin resistance plasmid DNA was conjugally transferred from two strains of E. faecalis HL-1 and HL-6 to S. aureus SK 982. The plasmid transfer frequency between S. aureus SK 982 and E. faecalis HL-1 or E. faecalis HL-6 was 6.3$\times10^{-4} and 3.7$\times10^{-5}$, respectively. Plasmid curing ratio after the treatment of ethidium bromide(10$\mu$/ml) to E. faecalis tarnsconjugants R-1 and R-6 were about 51% and 67%, respectively. The tetracycline gene was located in 2.15 Kb plasmid of E. faecalis HL-1, but it was not found in the E. faecalis HL-6 by Southern blot analyses. The antigenic components of E. faecalis HL-1, HL-6, R-1 and R-6 strains were analyzed by SDS-PAGE and immunoblotting. The E. faecalis strains had 7 to 16 polypeptide bands, however their major proteins were 97.8 and 26.8 Kd. At the Immunoblotting, 97.8, 95.8, 74.8, 63.5, 33.7 and 26.8 Kd polypeptides of the strains showed major antigenic activities with patient's sera infected intra-abdominally with an E. faecalis strain.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.156-165
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• 2001

Exogeneous application of pokeweed antiviral protein (PAP), a ribosomal-inacivating protein in the cell wall of Phytolacca americana (pokeweed) protects heterologous plants from viral and fungal infection. A cDNA clone of PAP introduced into Scrophularia buergeriana Miquel by thransformation with Agrobacterium tumefaciences. For plant transformation, explants were precultured on shoot induction medium without kanamycin for 2-5 day, and then they were cocultured with Agrobacterium for 10 minutes. The explants were placed on co culture medium in dark condition, $28^{\circ}C$ for 2days. After explants were washed in MS liquid medium, they were transferred into selection medium including kanamycin 50mg/L (MS salts+1mg/ l BAP+2mg/ l TDZ+0,2mg/ l NAA+MS vitamin+3% sucrose+0.8% agar, pH5.8). From PCR analysis, NPT II band was confirmed in transgenic plant genome and showed resistance against fungi in antifungal activity test. Micro assay to which protein extracted from transgenic line were added, revealed hyphae growth inhibition and no spore germination at high concentration. The characteristics of inhibited hyphae was represented transparent and thin. Expression of PAP in transgenic plants offers the possibility of developing resistance to viral and fungal infection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.428-434
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• 2005

For the purpose to verify the grain and evaluate milling properties of Korean waxy wheat, com­parison analysis between waxy wheat lines and their respective maternal parents were performed. The waxy lines showed various grain yields of 4.76${\~}$5.79 t/ha depending on parentages, which were corresponding to $80{\~}96\%$ levels of their respective maternal parents. One thousand grain weights of waxy lines were also lighter than its respective part in its parentage by exhibiting 32.8${\~}$34.6 g compared to 32.9${\~}$45.2 g of their parents. Test weights of waxy lines and their parents were 720${\~}$798 g/l and 786${\~}$797 g/l, respectively. The proportions of the grains above 2.5 mm in width were higher in order of Keumgang, Olgeuru, Geuru, SW97134, Suwon 292, Woori, SW97105, and SW97110. Waxy lines exhibited low milling properties by showing the straight flour yields ranging from $61.8\%$ to $67.1\%$ compared with the yields of their parents ranging from $66.1\%$ to $72.5\%$; the waxy lines were significantly lower in first break flour (Bl) and first reduction flour (Rl) yields in the Buller test mill, while significantly higher in the yields of second and third reduction flour (R2 and R3) than the respective ones of their parent wheat.

• Journal of Life Science
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• v.18 no.6
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• pp.789-795
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• 2008

To study the possible use of probiotics in fish farming, we evaluated antagonism of antibacterial strain Bacillus amyloliquefaciens H41 against the fish pathogenic bacterium Vibrio anguillarum NCMB1. The purification of growth inhibition factor produced by B. amyloliquefaciens H41 was achieved by obtaining supernatant of this bacterium. The growth inhibition factor was purified to homogeneity by 70% ammonium sulfate precipitation, DEAE-sephadex A-50 ion exchange chromatography, sephadex G-200 gel filtration column chromatography, and sephadex G-50 gel filtration column chromatography with 40.8 fold of purification and 2.9% yield. The molecular weight of the purified growth inhibition factor was 48 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The optimum pH and temperature for the growth inhibition factor were pH 7.5 and $30^{\circ}C$, respectively. The activity of growth inhibition factor was enhanced slightly by some metal ions, such as $Mg^{+2}$, $Mn^{+2}$, but was inhibited by the addition of $Co^{+2}$, $Hg^{+2}$, $Zn^{+2}$ and $Ag^{+2}$. NaCl stability of the growth inhibition factor was observed with 50% residual activity at 3% NaCl concentration. Toxicity test showed that the purified B. amyloliquefaciens H41 growth inhibition factor did not affect the live of Japanese flounder (Paralichthys olivaceus) and the effectiveness was 78% of residual lethality compared to commercial antibacterial agents.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.249-254
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• 2002

To determine the abilities as both lactic starter and probiotics for fermented foods, we investigated the potency of acid production, proteolytic activity and lactose metabolism of Lactobacillus amylovorus IMC-1. And the strain was cultured with lactococci in 10% skim milk medium. It was also examined the bactericidal action of antibacterial substance, produced by the strain IMC-1, against pathogenic bacteria. L. amylovorus IMC-1 showed excellent production of acid in 10% skim milk supplemented with yeast extract, and produced 0.8 and 2.7% of acid at 12 and 72 h incubation, respectively. It was found that the activity of ${\beta}-galactosidase$, about $39\;{\mu}M/minute/dry$ cell weight (mg), was stronger than that of $phospho-{\beta}-galactosidase$ in the strain IMC-1. The strain showed weak proteolytic activity in 10% skim milk, thus it produced 6 and $69\;{\mu}g/mL$ of free tyrosine at 12 and 72 h cultivation, respectively. It was known that the strain utilized mainly ${\alpha}-casein$ than ${\beta}-casein$ from patterns of SDS-PAGE. Mixed culture produced more acid than single cultures of L. amylovorus IMC-1 and Streptococcus thermophilus NIAI 510. Single culture of Str. thermophilus and mixed culture showed increasing cheese flavor with incubation times. Optimal fermentation time of mixed culture for the acid production and flora of lactic starter was 16 and 12 h by adding 0.1 and 0.5% of yeast extract to 10% skim milk, respectively. Antibacterial substance produced by the strain IMC-1 reduced about 2 log of the viable cell counts of both Escherichia coli O157 and Shigella flexneri after 24 and 4 h incubation, and they were not detected after 48 and 6 h incubation, respectively.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.480-485
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• 2019

The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

• Journal of Sasang Constitutional Medicine
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• v.9 no.1
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• pp.315-337
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• 1997

In order to compare the dffects of $Galg{\breve{u}}nhaegit'ang$(葛根解肌湯) of "Dongeuisusebowon(東醫壽世保元)and Won's(元)-$Galg{\breve{u}}nhaegit'ang$(葛根解肌湯) of "Dongeuisasansinpyun(東醫四象新編)" on the immune respone, Sprague-Dawley male rats were used and randomly divided into four groups. Normal group was under normal condition, Control group was injected i.v. with 2mg/kg Methotrexate(MTX) on the 9th day and 11th day after sensitization with SRBC on the 5th day, $Galg{\breve{u}}nhaegit'ang$ group was fed with 1ml of $Galg{\breve{u}}nhaegit'ang$ and Won's-$Galg{\breve{u}}nhaegit'ang$ group was fed with 1ml of Won's-$Galg{\breve{u}}nhaegit'ang$ by oral during eighteen days. In the 9th day and the 11th day after oral feeding with medication, MTX was injected in tail of rats in order to reduce immune function. Leukocyte count, lymphocyte ratio, lymphocyte count of spleen, lymphocyte count of bone marrow, contact hypersensitivity to DNFB, morphologic change of thymus cell, and electropherogram of serum protein were estimated and compared according to the group. The results are as follows : 1. Before and after MTX injection, leukocyte(WBC) count was increased signigicantly in Won's-$Galg{\breve{u}}nhaegit'ang$ group compared to control group. $Galg{\breve{u}}nhaegit'ang$ group had no significant difference compared to control group. 2. Before and after MTX injection, lymphocyte ratio was not significantly different in Won's-$Galg{\breve{u}}nhaegit'ang$ group and in $Galg{\breve{u}}nhaegit'ang$ group compared to control group. 3. The lymphocyte count of spleen was increased significantly in $Galg{\breve{u}}nhaegit'ang$ group compared to control group and Won's-$Galg{\breve{u}}nhaegit'ang$ group. Won's-$Galg{\breve{u}}nhaegit'ang$ group had no significant difference compared to control group. 4. The lymphocyte count of bone marrow was increased significantly in Won's-$Galg{\breve{u}}nhaegit'ang$ group compared to control group and $Galg{\breve{u}}nhaegit'ang$ group. $Galg{\breve{u}}nhaegit'ang$ group had no significant difference compared to control group. 5. Contact hypersensitivity was increased significantly in Won's-$Galg{\breve{u}}nhaegit'ang$ group compared to other group. $Galg{\breve{u}}nhaegit'ang$ group had no significant difference compared to control groups. 6. In the morphologic change of thymus cell, control group compared to normal group had a indistinct boundary between cortex and medulla and lymphocyte cell density of thymus was low. $Galg{\breve{u}}nhaegit'ang$ group and Won's-$Galg{\breve{u}}nhaegit'ang$ group compared to control group had a definite boundary between cortex and medulla and lymphocyte cell density of thymus was high. 7. In the SDS-PAGE electropherogram of serum protein, Won's-$Galg{\breve{u}}nhaegit'ang$ group had a wide band of nearby 25,000 Dalton, and which meant IgG generated more actively. Considering this results, $Galg{\breve{u}}nhaegit'ang$ group and Won's-$Galg{\breve{u}}nhaegit'ang$ group have an effect on the depression of immune function induced by MTX, and especially Won's-$Galg{\breve{u}}nhaegit'ang$ group has an significant effect than $Galg{\breve{u}}nhaegit'ang$ group.