• KSBB Journal
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• v.11 no.6
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• pp.654-662
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• 1996

Bacterial strains which degrade crude oil were isolated by liquid culture from oil-spilled soil, and four isolates were selected among them. The strain Hl7-1 was finally selected after testing emulsifying activity and oil conversion rate. The strain Hl7-1 was identified as a Nocardia sp. based on the test for morphological, biochemical and physiological characteristics. It appears to be highly specialized for growth on crude oil in minimal salts medium since it showed preference for oil or degradation products as substrates for growth. It was found that it could grow on at least fifteen different hydrocarbons. The optimum cultural and environmental conditions were seeked. Cell growth and emulsification activity as a function of time were also determined. Crude oil degradation and the reduction of product peak was identified by the analysis of remnant oil by gas chromatography after 3 days of cultivation. Approximately 83% of oil were converted into a form no longer extractable by organic solvents.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.302-308
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• 1997

The purpose of this study was to investigate the extraction yield and quality stability as to the oleoresin process with large amount of onion at one time. The first mixed-product is raw onion juice which was reduced the compression and concentrated by Brix 70% mixed together wit the residue which was extracted and concentrated by ethanol, the second product manufactured by the same method above after the autoclaving with onion, and the other product is made by grinding by 50mesh to freeze-dried onion. Each of yields were 7.3, 9.1 and 0.8% and each of total sugar content was 616.4, 712.3 and 150.3mg/g. Therefore the product extracted by ethanol from freeze-dried onion was very low in yield and total sugar content. By the index of the overall odor intensity, contents of total pyruvate were 1,733.7, 520.6, and 2,716.5$\mu\textrm{g}$/g for each product. As a result, oleoresin onion processing that desired to use raw onion was remarkable for odor recovery. For the homogenous mixture with concentrate of onion juice and ethanol extract were emulsified by the addition of 2% of PGDR(polyglycerol condensed ricinoleate) and agitation(10,000rpm, 30 minutes). At this time, interfacial tension was 1.9 dyne/cm and the formation of emulsion was for 96.2% when left over 24hours in 6$0^{\circ}C$. When it was to be centrifuged(2,000$\times$G, 80 minutes) after emulsification, the volume of emulsion level without seperation was 92.6%, and very high in emulsification stability. The induced heating-oxidize with soy bean oil and sesame oil added to 1% of onion oleoresin, induction-time extension effect appeared with antioxidant activity that was applicable for 80.8~82.2% as to the effect of addition of 0.02% BHA.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.268-274
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• 2006

Bacillus sp. DYL130 producing biosurfactant was isolated from soil samples in the Duck-yu mountain and identified as Bacillus sp. by analysis of 16S rDNA sequence. Purification of the biosurfactant was performed by using affinity chromatography and TLC. The biosurfactant of culture medium from Bacillus sp. DYL130 was eluted with 100% methanol using affinity chromatography. To remove methanol, a rotary evaporator was used and enrichment sample was dissolved in alkaline water(pH 10). The purified biosurfactant was identified by TLC. It was confirmed that the Rf value of the biosurfactant was 0.78. Antifungal activity against Botrytis cineria was showed the strongly activity as active antagonist. Maximum emulsification activity and stability were obtained from soybean oil. The critical micelle concentration (CMC) of purified biosurfactant was 35mg/l and the purified biosurfactant inhibited biofilm forming by Bacillus sp..

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.1
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• pp.1-14
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• 2024

We investigated the functional properties and in vitro bioactivity of protein isolates (RPIs) recovered from olive flounder Paralichthys olivaceus roes by isoelectric solubilization/precipitation process, according to pH-shift treatments. The buffer capacity of RPIs was shown to be stronger in alkaline pH than in acidic pH. Water holding capacity of RPIs was in range of 4.5-5.2 g/g protein with no significant differences (P>0.05). The foaming capacity and emulsifying activity index of RPIs did not show any significant differences between RPI-1 (pH 11/4.5) and 3 (pH 12/4.5), however they were superior to RPI-2 (pH 11/5.5) and 4 (pH 12/5.5). The 2,2'-azino-bis-3-ethylbenzo-thiazoline-6-sulfonic acid radical scavenging activity of RPI-3 (2.5 mg protein/mL) was 102.4 ㎍/mL, and the angiotensin I converting enzyme inhibitory activity was 30.8%. Among the RPIs, RPI-3 was relatively superior in protein functional properties such as buffer capacity, foaming capacity, emulsification, and anti-oxidative activity. Therefore, we suggest that RPI prepared from olive flounder roes could serve as a potential food resource.

• KSBB Journal
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• v.13 no.5
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• pp.606-614
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• 1998

In this study, biodegradation rate of Arabian light crude oil by mixed cultures of selected petroleum-degraders was determined. Their modes of hydrocarbon uptake were then observed to determine whether there are differences in biodegradation rate by the mixed cultures. By the mixed cultures of petroleum-degraders having same modes of hydrocarbon uptake, such as strain US1 and K1 (using pseudo-solubilized hydrocarbons by a biosurfactants), K2-2 and P1(using hydrocarbons by direct contact), CL 180 and IC-10 (mixed type of uptake modes), the biodegradation rates of aliphatics in the crude oil were increased more than those by their pure cultures, about 40%, 25% and 20%, respectively. Biodegradation rate of strain KH3-2 (using only water- dissolved hydrocarbons) was increased by mixed cultures with strain K1, CL180 or IC-10 possessing high emulsifying activity. However, the biodegradation rate of the crude oil was decreased about 20%-40% by the mixed cultures of petroleum-degraders having different mode of hydrocarbon uptake, such as addition of strain US1 or K1 in the cultures of K2-2 or P1. Biosurfactants produced by US1 or K1 seems to enhance the emulsification of crude oil in aqueous phase but inhibit the attachment of K2-2 or P1 to crude oil. As same phenomena, the addition to Triton X-100 into the culture of strain US1, K1, CL180, IC-10 or KH3-2 increased the biodegradation rate, but the addition in the culture of strain K2-2 or P1 decreased the biodegradation rate. The mixed culture made of CL180, IC-10 and KH3-2 degraded 61.5% of aliphatics and 69% of aromatics in 3% (v/v) of Arabian light crude oil added.

• Korean Journal of Food Science and Technology
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• v.20 no.5
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• pp.625-630
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• 1988

Phosphorylation of soy protein by sodium trimetaphosphate and acetylation of soy protein by acetic anhydride were performed. Then, the functional properties of modified soy proteins were compared with that of unmodified soy protein. Isolated soy protein prepared from defatted soybean flake had protein content of 92.7% as moisture-free basis. The phosphorylated soy protein showed higher solubility, foaming properties, and water holding capacity than unmodified soy protein. Acetylation of soy protein increased emulsification activity and foaming properties greatly, whereas decreased the solubility at pH 8.0. Isoelectric pHs of phosphorylated and acetylated soy protein were shifted to acidic regions(pH 3.0 and pH 4.0) from pH 5.0, which was the isoelectric pH of unmodified soy protein. Soy protein seems to be aggregated during phosphorylation and acetylation procedure, judging form Sepharose CL-4B gel filtration profiles. The modified soy proteins showed increased mobilities to anode direction in disc-gel electrophoresis.

• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.663-670
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• 2018

The present study focused on the production, characterization, and in vitro prebiotic evaluation of an exopolysaccharides (EPS) from Bacillus sonorensis MJM60135 isolated from ganjang (fermented soy sauce). Strain MJM60135 showed the highest production ($8.4{\pm}0.8g/l$) of EPSs compared with other isolates that were screened for EPS production based on ropy culture morphology. Furthermore, MJM60135 was cultured in 5 L of medium and the EPS was extracted by ethanol precipitation. The emulsification activity of the EPS was higher in toluene than in o-xylene. Fourier transform infrared spectroscopy analysis showed the presence of hydroxyl and carboxyl groups and glycosidic linkages. The isolated EPS contained mannose and glucose, as observed by thin-layer chromatography analysis of the EPS hydrolysate. Lactic acid bacteria (LAB) and pathogenic E. coli K99 and Salmonella enterica serovar Typhimurium were tested for their growth utilizing the EPS from B. sonorensis MJM60135 as the sole carbon source for its possible use as a prebiotic. All the tested LAB exhibited growth in the EPS-supplied medium compared with glucose as carbon source, whereas the pathogenic strains did not grow in the EPS-supplied medium. These findings indicate that the EPS from B. sonorensis MJM60135 has potential application in the bioremediation of hydrocarbons and could also be used as a prebiotic.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.716-723
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• 2006

A biosurfactant-producing bacterial strain was selected from oil-contaminated soil because of its ability to degrade crude oil and tributyrin $(C_{4:0})$. The strain was identified as Bacillus subtilis A8-8 based on its morphological, biochemical, and physiological characteristics. When B. subtilis A8-8 was grown with crude oil as the sole carbon source, the biosurfactant from the strain emulsified crude oil, vegetable oil, and hydrocarbons. Soybean oil was the optimum substrate for the emulsifying activity and emulsion stability of the biosurfactant, both of which were superior to those of several commercially available surfactants. The biosurfactant was purified by a procedure including HCl precipitation, methanol treatment, and silica-gel chromatography. The partially purified biosurfactant was analyzed by TLC (thin-layer chromatography), SDS-PAGE, and HPLC and it reduced the surface tension of water from 72 mN/m to 26 mN/m at a concentration of 30 mg/l. Therefore, the purified lipopeptide biosurfactant has strong properties as an emulsifying agent and acts as an emulsion-stabilizing agent.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.524-532
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• 2018

In this study, two types of amino acids-based anionic biosurfactants such as potassium cocoyl glutamate (CTK) and sodium cocoyl glutamate (CTN) were synthesized from coconut oils and the structure elucidation of CTK and CTN was carried out by using FT-IR, $^1H-NMR$ and $^{13}C-NMR$ spectrophotometries. Measurements of interfacial properties such as static and dynamic surface tensions and emulsification activity showed that both CTK and CTN were surface-active and effective in lowering the interfacial free energy. In particular, the CTK surfactant was found to be more efficient in reducing the interfacial free energy since the larger number of CTK molecules was preferentially adsorbed at the air-water interface due to the higher hydrophobicity and larger mobility of CTK than those of using CTN, indicating possible uses in cosmetics and household products formulation.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.1-8
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• 1987

Eighty eight percent of succinylation at $\varepsilon$-amino group of lysine was obtained from silkworm larvae protein concentrate and it resulted in increased bulk density and fat absorption, improved flavor and color, increased solubility over fivefold. Both emulsifying activity and emulsion stability of the succinylated protein were improved by 30% and emulsifying capacity was enhanced by 4%. Foaming capacity of the succinylated Protein concentrate was improved by 30% and foaming stability improved fivefold. The viscosity of succinylated silkworm larvae protein concentrate was increased at all concentrations and reached the highest at 4~5% of concentations. Acetylation of silkworm larvae protein concentrate caused negligible change in the functional properties studied. Therefore, high emulsification properties of silkworm larvae protein concentrate would be a good protein source for the emulsified foods.