• 한국수산과학회지
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• 제32권6호
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• pp.798-802
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• 1999

찰가자미 (Microstomus achne) 자어를 대상으로 해양세균 (Erythrobacter sp. S$\pi$-1)을 공급한 rotifer와 Artemia의 영양개선효과를 Super Selco, 유지효모, 해수산 Chlorella와 비교 조사하였다 해양세균이 포함된 EPS-SR과 Super Selco를 공급한 rotifer에서 지방산중 DHA의 비율이 해수산 Chlorella를 공급한 rotifer보다 높았고, 그 결과 이들을 섭취한 자어의 성장이 높게 나타났다 또한 해양세균이 포함된 EPS-A를 공급한 Artemia는 DHA와 n-3 HUFA의 비율이 다른 영양강화제와 영양강화제를 공급하지 않은 Artemia보다 높았다. 따라서 ESP-A를 공급한 자어의 성장과 생존률이 다른 영양강화제와 영양강화제를 공급하지 않은 자어보다 높게 나타났다. 해양세균 Erythrobacter sp. S$\pi$-1의 먹이 효율적인 측면에서 찰가자미 자어를 대상으로 할 때 먹이생물의 영양을 개선시킬 수 있을 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.535-541
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• 2017

Two Gram-staining-negative, red-pinkish, coccus-shaped, non-motile, and aerobic bacterial strains, designated $Ant21^T$ and Ant22, were isolated from the Antarctic coastal sea water. Strains $Ant21^T$ and Ant22 showed UVC and gamma radiation resistance. Phylogenetic analyses based on 16S rRNA gene sequences determined that these strains belong to the genus Deinococcus. Through the analyses of the 16S rRNA gene sequences, strains $Ant21^T$ and Ant22 were found to have 97.7% and 97.8% similarity to Deinococcus marmoris DSM $12784^T$ and 97.0% and 97.2% similarity to Deinococcus saxicola AA-$1444^T$, respectively. The sequence similarity with the type strains of other Deinococcus species was less than 96.9% for both strains. Strains $Ant21^T$ and Ant22 shared relatively high 16S rRNA gene sequence similarity (99.3%) and had a closely related DNA reassociation value of $84{\pm}0.5%$. Meanwhile, they showed a low level of DNA-DNA hybridization (<30%) with other closely related species of the genus Deinococcus. The two strains also showed typical chemotaxonomic features for the genus Deinococcus, in terms of the major polar lipid (phosphoglycolipid) and the major fatty acids ($C_{16:0}$, $C_{16:1}$ ${\omega}6c/{\omega}7c$, $iso-C_{17:0}$, and $iso-C_{15:0}$). They grew at temperatures between $4^{\circ}C$ and $30^{\circ}C$ and at pH values of 6.0-8.0. Based on the physiological characteristics, the 16S rRNA gene sequence analysis results, and the low DNA-DNA reassociation level with Deionococcus marmoris, strains $Ant21^T$ ($=KEMB\;9004-167^T$ $=JCM\;31436^T$) and Ant22 (KEMB 9004-168 =JCM 31437) represent novel species belonging to the genus Deinococcus, for which the name Deinococcus rubrus is proposed.

• 생명과학회지
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• 제27권10호
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• pp.1152-1160
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• 2017

단세포 녹조류 균주를 경상북도 울릉군 울릉도 거북바위 주변 조수웅덩이로부터 순수분리하여 형태적, 분자적, 및 생화학적 특성을 분석한 결과 옥세노클로렐라 프로토테코이드에 속하는 것으로 밝혀졌다. 본 종은 현재까지 한국에서 공식 기록이 없는 미기록종으로 옥세노클로렐라 프로토테코이드 MM0011 균주라고 명명하였으며, 생장, 지질/광합성 색소 조성 및 바이오매스 특성에 대해 조사를 실시하였다. 분리균주는 광범위한 온도($5-35^{\circ}C$)에서 생장할 수 있었으며 1.5 M 염화나트륨 농도까지 생존할 수 있었다. 가스크로마토그래프/질량분석기를 이용한 분석 결과, 본 균주에는 영양적으로 중요한 불포화지방산이 풍부한 것으로 나타났으며, 특히 리놀네산(27.6%) 및 알파 리놀렌산(37.2%)이 주요 지방산 성분으로 확인되었다. 따라서 본 토착 미세조류 균주는 어유 또는 식물성유를 대체할 수 있는 잠재적인 오메가-3 및 오메가-6 불포화지방산 원료가 될 수 있을 것으로 사료된다. 또한, 고부가가치 항산화 물질인 루테인이 보조색소로서 본 균주에 의해 생합성 되는 것으로 밝혀졌다. 일반성분분석 결과 MM0011 균주의 휘발성물질 함량은 85.6%였으며, 원소분석 결과 총 발열량은 $20.3MJ\;kg^{-1}$으로 나타났다. 또한 배지로부터 40.5%의 전질소와 27.9%의 전인을 각각 제거할 수 있어 향후 바이오연료 원료물질 생산과 오 폐수처리를 연계할 수 있는 가능성 역시 제시하였다. 추가적으로 MM0011 바이오매스는 높은 단백질 함량(51.4%)을 갖고 있어 우수한 동물사료의 원료가 될 수 있는 가능성도 보여주고 있다. 따라서, 본 균주는 미세조류 기반 생화학 물질 생산 및 바이오매스 원료로서 상업적인 이용 가능성이 높음을 시사한다.

• 한국수산과학회지
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• 제48권4호
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• pp.417-425
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• 2015

Semi-dried conger eel Conger myriaster is considered as a health food in Korea due to its richness in vitamins, minerals, proteins and omega-3 fatty acids. This study characterize the sanitary quality of commercial semi-dried conger eel for developing high quality semi-dried products and suggested the guideline for controlling the quality. Moisture content ranged from 41.2% to 73.4% (mean: 61.5%), volatile basic nitrogen ranged from 16.1 to 93.6 mg/100 g (mean: 55.1 mg/100 g), and peroxide value ranged from 15.2 to 69.8 meq/kg. Viable cell counts ranged between 6.51 and 8.53 log CFU/g, while the Escherichia coli count ranged from undetectable to 4.6 log CFU/g. Based on these chemical and microbial findings, we suggest that provisions be established for development of high quality semi-dried conger eel as follows: 50-68% for moisture content, < 50 mg/100 g for volatile basic nitrogen content, < 60 meq/kg for peroxide value, and negative for E. coli. Among the 16 commercial semi-dried conger eel products used in this study, the standard-passed product was only GS-L.

• Journal of Microbiology
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• 제45권6호
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• pp.505-509
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• 2007

An obligately aerobic bacterium, strain KOPRI $20902^T$, was isolated from a marine sediment in Ny-${\AA}$lesund, Spitsbergen Islands, Norway. Cells were irregular rods and motile with polar monotrichous flagellum. The optimum growth temperature was $17-22^{\circ}C$. Cells grew best in pH 7.0-10.0 and 3-4% sea salts (corresponding to 2.3-3.1% NaCl). The novel strain required $Ca^{2+}$ or $Mg^{2+}$ in addition to NaCl for growth. Sequence analysis of 16S rRNA gene revealed that the Arctic isolate is distantly related with established species (<92.4% sequence similarity) and formed a monophyletic group with Cellvibrio, which formed a distinct phylogenetic lineage in the order Pseudomonadales. Predominant cellular fatty acids [$C_{16:1}\;{\omega}7c/15:0$ iso 2OH (45.3%), $C_{16:0}$ (18.4%), ECL 11.799 (11.2%), $C_{10:0}$ 3OH (10.4%)]; DNA G+C content (37.0 mol%); nitrate reduction to nitrogen; absence of aesculin hydrolysis, N-acetyl-${\beta}$-glucosaminidase and esterase; no assimilation of arabinose, galactose, glucose, lactose, maltose, and trehalose differentiated the strain from the genus Cellvibrio. Based on the phylogenetic and phenotypic characteristics, Dasania marina gen. nov., sp. nov. is proposed in the order Pseudomonadales. Strain KOPRI $20902^T$ (=KCTC $12566^T$=JCM $13441^T$) is the type strain of Dasania marina.

• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.971-975
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• 2007

Two experiments were conducted to evaluate the feeding values of red pepper seed oil meal (RPSOM) and to investigate its dietary supplementation on broiler performances. In Exp. 1, nutritional values of RPSOM were evaluated by analyzing chemical composition and determining true metabolizable energy (TME), nitrogen corrected TME (TMEn) and true available amino acid (TAAA). RPSOM contained 22.50% of CP, 4.75% of ether extract, 27.70% of crude fiber, 4.73% of crude ash and 49.97 ppm of xanthophylls. The contents of capsaicin and dihydrocapsaicin were 34 mg and 31 mg/100 g DM, respectively. The values of TME and TMEn determined by force-feeding 16 roosters were 1.73 kcal/g and 1.63 kcal/g DM, respectively. The average TAAA value of 17 amino acids was 85.22%. In Exp. 2, a total of 225 Ross male broiler chicks, 3 weeks old, were randomly divided into 9 groups of 25 birds each and assigned to three experimental diets containing 0 (control), 5 or 10% RPSOM fed ad libitum for 3 weeks. No significant differences were observed in growth performances and carcass characteristics. The level of serum cholesterol in the 10% RPSOM group was significantly lower than that of the control group (113.92 vs. 137.50 mg/dl). The dietary RPSOM at 5 and 10% levels increased the content of C18:2 ${\omega}{\sigma}$ in leg muscle compared with the control group. The results suggested that RPSOM can be included into broiler feed up to 10% without any negative effects on broiler performances and physiological responses and used as a non-conventional plant protein source, if its nutritional values are well evaluated.

• 한국식품영양과학회지
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• 제35권9호
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• pp.1224-1231
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• 2006

고급불포화지방산인 docosahexaenoic acid ethylester (DHAEE)와 sucrose를 transesterification반응을 하여 sucrose ester를 기질 및 촉매의 비율, 반응시간, 용매사용 및 기압 등을 달리하여 합성하고, 합성율을 살펴보았고, 특히, 섭취 시 인체 내에서 이용 가능한 DHA를 함유하고 있으며, hydrophilic한 유화제로써 sucrose fatty acid mono ester의 합성율을 높이는 합성조건을 연구하였다. 무용매 상태에서의 sucrose ester의 합성율이 낮았기 때문에 반응용매로써 dimethyl sulfoxide(DMSO)를 사용하여 몰비율과 반응시간에 따른 합성을 실시하였다. 여러 반응조건 중 DHAEE의 전환율(%)은 sucrose:DHAEE의 몰비율이 1:0.98, 1:0.60, 1:0.40, 1:0.20인 SE#4, SE#5, SE#6, SE#7에서 모두 96% 이상을 나타내었다. 특히, SE#6(1:0.4 mole)에서 반응시간에 따른 전환율과 sucrose ester의 조성변화를 살펴본 결과, 반응시간 1시간일 때 55.3%의 전환율(mono ester 91.6%)을 보였고, 이후 반응 3.5시간일 때에는 97.1%(mono ester 66%)의 전환율을 보였다. 따라서 반응초기에 대부분의 sucrose ester가 합성되며, 특히 반응시간이 길어짐에 따라 mono ester에서 di-, tri- 및 polyester로 그 조성이 점차 변화됨을 확인하였고, 기질 중 DHAEE의 비율이 증가할수록 sucrose mono ester의 생성은 감소한 반면에, sucrose di-, tri- 및 polyester의 생성은 증가함을 확인하였다. 연구된 합성조건 중 sucrose mono ester의 합성은 1:0.2(sucrose:DHAEE)의 몰비율로 2.5시간동안 반응(SE#7)하였을 때 98.5%의 높은 전환율을 보이면서 그 조성은 87.3%로 가장 높게 합성되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권10호
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• pp.1621-1629
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• 2019

Objective: The objective of this study was to evaluate the physicochemical, sensory and taste characteristics of commercial, frozen, dry, and wet aged Hanwoo sirloin. Methods: Grade 2 sirloin from 6 Hanwoo steers (about 30 months old) were obtained after 5 days postmortem. Samples were assigned to four groups which were commercial beef (CON, control group), frozen beef (Hanwoo frozen, HF; 40 days in $-18^{\circ}C$ freezer), wet-aged beef (Hanwoo wet-aging, HW; 21 days), and dry-aged beef (Hanwoo dry-aging, HD; 40 days). HW and HD were stored in a $80%{\pm}5%$ relative humidity cooler at $1^{\circ}C$. Results: The HF group showed a significantly higher cooking loss and expressible drip with significantly higher pH compared to other groups. In addition, protein and fat contents in the HD group were higher than those in other groups (p<0.05). The shear forces in the HW and HD groups were significantly lower than those in the CON group. The HD group had significantly higher omega-3 and polyunsaturated fatty acids compared with other groups. Glutamic acid levels in the HD group were significantly higher compared with those in other groups. Electronic tongue analysis revealed that sourness of the HD group was lower than that of other groups, whereas the HD group showed significantly higher umami, richness, and saltiness compared to other groups (p<0.05). Sensory test results revealed that the HW group had significantly higher tenderness, while the HD group had significantly higher chewiness, juiciness, and overall acceptability scores. Conclusion: These results suggest that both wet- and dry-aging treatments can effectively improve sensory characteristics, and dry-aging was much more useful to enhance umami tastes and meat quality of 2 grade Hanwoo sirloins.

• 한국축산식품학회지
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• 제39권2호
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• pp.309-323
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• 2019

Fish oil consists of omega-3 fatty acids which play an important role in human health. Its susceptibility to oxidation causes considerable degradation during the processing and storage of food products. Accordingly, encapsulation of this ingredient through freeze drying was studied with the aim of protecting it against environmental conditions. Gum arabic (GA) was used as the wall material for fish oil nanoencapsulation where tween 80 was applied as the emulsifier. A water-in-oil (W/O) emulsion was prepared by sonication, containing 6% fish oil dispersed in aqueous solutions including 20% and 25% total wall material. The emulsion was sonicated at 24 kHz for 120 s. The emulsion was then freeze-dried and the nanocapsules were incorporated into probiotic fermented milk, with the effects of nanocapsules examined on the milk. The results showed that the nanoparticles encapsulated with 25% gum arabic and 4% emulsifier had the highest encapsulation efficiency (EE) (87.17%) and the lowest surface oil (31.66 mg/100 kg). Using nanoencapsulated fish oil in fermented milk significantly (p<0.05) increased the viability of Lactobacillus plantarum as well as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) contents. The fermented milk sample containing fish oil nanoencapsulated with 25% wall material and 4% emulsifier yielded the greatest probiotic bacterial count (8.41 Log CFU/mL) and the lowest peroxide value (0.57 mEq/kg). Moreover, this sample had the highest EPA and DHA contents. Utilizing this nanoencapsulated fish oil did not adversely affect fermented milk overall acceptance. Therefore, it can be used for fortification of low fat probiotic fermented milk.

• 환경생물
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• 제37권4호
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• pp.526-534
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• 2019

Chlorella gloriosa (Chlorellaceae, Trebouxiophyceae) was isolated from seawater off the coast of the Dokdo Islands in Korea. An axenic culture was established using the streak-plate method on f/2 agar media supplemented with antibiotics, allowing identification of the isolate by morphological, molecular, and physiological analyses. The morphological characteristics observed by light and electron microscopy revealed typical morphologies of C. gloriosa species. The molecular phylogenetic inference drawn from the small-subunit 18S rRNA sequence verified that the microalgal strain belongs to C. gloriosa. Additionally, gas chromatography-mass spectrometry analysis showed that the isolate was rich in nutritionally important omega-3 and -6 polyunsaturated fatty acids and high-performance liquid chromatography analysis revealed that the high-value antioxidants lutein and violaxanthin were biosynthesized as accessory pigments by this microalga, with arabinose, galactose, and glucose as the major monosaccharides. Therefore, in this study, a Korean marine C. gloriosa species was discovered, characterized, and described, and subsequently added to the national culture collection.