This research aimed to examine the effects of grapefruit seed extract (GSE) at various concentrations on the microbial safety and physicochemical characteristics of onion puree (0.01~0.1%). The onion puree was kept at 4℃ for 14 days. The results of the study indicated that the addition of GSE did not cause any significant changes in the sample’s brix degree and viscosity in onion puree (p<0.05). However, as the concentration of GSE increased, the pH level decreased. On the other hand, as GSE was added, the lightness of the onion puree increased, while the redness and yellowness decreased. Compared to pure onion puree, the GSE-incorporated onion puree had higher levels of total flavonoid and total polyphenol content, indicating that it helps to maintain antioxidant activities. Based on the microbial safety test, aerobic bacteria, yeast, and mold were absent until day 14 of storage. In conclusion, the study suggests that the addition of GSE to onion puree increases its antioxidant activity and shelf-life.

살모넬라증과 부루셀라증은 가축 및 사람에 심각한 피해를 유발하는 질병으로, 축산업과 식품산업에 많은 경제적 손실을 초래하고 있다. 본 연구에서는, 자몽종자추출물, 구연산, 사과산 그리고 염화벤잘코늄을 주성분으로 하는 스프레이형 소독제의 Salmonella Typhimurium과 Brucella ovis에 대한 효력시험을 수행하였다. 살균효력시험은 배지희석법에 따라 수행하였으며, 스프레이형 소독제와 시험 세균들을 처리조건에 따라 경수와 유기물로 희석하여 반응을 시켰다. 유기물 조건에서, Salmonella Typhimurium과 Brucella ovis에 대한 스프레이형 소독제의 살균력은 경수조건에서의 살균력과 비교하여 낮게 나타났는데, 이는 유기물들에 의한 소독제의 살균 유효성분에 대한 저해작용에 따른 것으로 사료된다. 스프레이형 소독제는 Salmonella Typhimurium과 Brucella ovis와 같은 인수공통전염병 유발 병원균들에 대해 살균효과를 나타내어, 살모넬라증과 브루셀라증과 같은 세균성 질병의 확산을 제어하는데 효과적으로 이용될 수 있을 것으로 사료된다.

본 연구는 수확 후 감귤의 부패과 발생 억제를 위하여 grapefruit seed extract과 oregano oil이 혼입된 carnauba 코팅 과 calcium oxide이 혼입된 chitosan 코팅을 감귤에 적용하여 Penicillium italicium 저해 효과에 대하여 연구하였다. carnauba 수용액(18%(w/w))에 grapefruit seed extract 또는 oregano oil을 단독으로 각각 0.3-1%(w/w) 첨가하였고, grapefruit seed extract과 oregano oil을 0.75:0.25, 0.5:0.5,그리고 0.25:0.75(w/w)의 비율로 혼합하여 첨가하였다. 또한 1% chitosan 수용 액의 경우 0.3-3%(w/w)의 calcium oxide을 첨가하여 코팅제를 개발하였다. 감귤 과피에 접종된 P. italicium에 대한 각 코팅제의 저해 효과는 부패과 발생률(%)로 표현하였다. carnauba wax 코팅의 경우, grapefruit seed extract을 단독으로 1% (w/w) 첨가, grapefruit seed extract과 oregano oil을 혼합하여 0.5:0.5%(w/w) 비율로 첨가하였을 때 부패과 발생률은 각각 23.6%와 25%로 유의적으로 가장 낮았고(P<0.05), calcium oxide을 첨가한 chitosan 코팅의 경우 calcium oxide의 농도와 관계없이 모든 조건에서 부패과 발생률이 유의적 차이를 보이지 않았다(P>0.05). 따라서 grapefruit seed extract 과 oregano oil이 혼입된 carnauba wax 코팅은 감귤의 저장 중 부패에 관여하는 P. italicium를 저해하여 저장성을 향상 시킬 수 있는 것으로 사료되었다.

본 연구는 자몽종자추출물이 도포 포장지의 항균활성에 미치는 영향을 알아보았다. 저장 안전성 중 항균력을 확인 하기 위하여 그람 양성균(B. cereus, L. monocytogenes) 2종 과 그람 음성균(E. coli, S. enteritidis) 2종을 선택하였다. 자몽종자추출물의 농도별(60-5,000 ppm)에 따른 그람 양성 균의 투명환 크기는 최저 5 mm에서 최고 21 mm로 나타내 었다. 또한 그람 음성균의 투명환 크기는 최저 0 mm에서 최고 7 mm로 나타내었다. 자몽종자추출물을 농도별(60- 5,000 ppm)로 도포 포장시킨 경우 그람 양성균의 투명환 크기는 최저 5 mm에서 최고 19 mm로 나타내었다. 또한 그람 음성균의 투명환 크기는 최저 7 mm에서 최고 11 mm 로 나타내었다. 자몽종자추출물을 처리한 도포 포장지를 이용하여 즉석섭취 식품에 대한 저장 안정성을 알아본 결 과, GFSE의 농도(1,000, 5,000, 10,000 ppm) 차이에 따라 각각 11시간, 16시간, 18시간 동안 신선도가 유지 되었고, 일반 세균수 측정 결과, 1,000, 5,000 ppm 및 10,000 ppm 에서 각각 4.5 log CFU/g, 4.8 log CFU/g, 4.2 log CFU/g로 측정되어 저장성을 증가 시킴을 알 수 있었다.

본 연구에서는 천연물질인 자몽종자추출물, 코치닐색소, 녹차추출물의 흥미첨가농도범위를 각각 0.02-0.08, 0.05-0.117 및 0.05-0.117%(w/w)로 놓았으며 혼합비율로서 혼합물 구조모형으로 설계하여 돈육포의 품질특성을 반응표면분석법으로 비교분석하였다. 색상 면에서 a값에서는 자몽종자추출물, 코치닐색소, 녹차추출물을 각각 0.02, 0.15 및 0.05%의 농도로 첨가 시 가장 높은 값인 14.5를 나타내었으며 천연물질을 첨가하지 않은 대조구는 7.9이었다. 60oC의 가속저장에서 대조구의 경우 저장 7일 후 TBA값의 증가정도는 80.20%이었으며 처리구 중 가장 작은 값을 보인 것은 자몽종자추출물, 코치닐색소, 녹차추출물의 농도가 각각 0.05, 0.05 및 0.10%에서 나타났으며 그때의 증가율은 16.44%이었다. 저장초기 천연첨가물질 혼합비율에 따라서 총 균수는 3.39-3.69 log CFU/g로 큰 차이는 없었으며 대조구의 3.41 log CFU/g과도 차이를 나타내지 않았다. 25oC의 저장에서 대조구의 경우는 7일 후 약간 증가하였으나 천연물질을 첨가한 경우에는 대부분 감소하였다.

This study was conducted to investigate the antimicrobial activity of grapefruit extracts and polylysine mixture against food-borne pathogens. The mixture was showed a potent and quick antibacterial activity for 5 major bacteria causing food poisoning i.e. Escherichia coli, Escherichia coli O-157, Salmonella typhi, Staphylococcus aureus, Vibrio cholerae. The antibacterial effect of the mixture on the ordinary bacteria inhibiting on the surface of lettuce was lasted even 6 hrs after the treatment, however the mixture was non-effective on the color, smell and taste of lettuce. The treatment with 10% mixture solution of the foods such as fish, meat, rice and bread suppressed the growth of the bacteria and kept the foods more freshly than the untreated foods.

Chicken skins or carcasses inoculated with Salmonella typhimurium were exposed to 0.1 or 0.5% grapefruit seed extracts (DF-100) for 1 or 3 min to evaluate antibacterial activity of DF-100 and its possible application in proultry processing. The numbers of live salmonellae on chicken skins were reduced by 0.8-1.2 logs/㎠ with 0.1% and by 1.6-1.7 logs/㎠ with 0.5% DF-100. Dipping chicken carcasses into 0.5% DF-100 for 3 min reduced salmonellae by 4.3 logs/ carcass. Scanning electron microaoopy showed that DF-100 killed the cells attached but did not detach cells from the skin. No odor or changes in the color of chicken skin were detected after DF-100 treatment.

The antibacterial and antifungal effect of grapefruit seed extract(GFSE) was investigated for its purpose of application to a diverse spectrum of field as sanitizers, disinfectants and preservatives. GFSE showed comparatively high content of such flavoniods as naringin and hesperidin and ascorbic acid. GFSE containing a low level of organic acids is a heavy viscous and water-soluble liquid. As a result of the antimicrobial test of GFSE, Bacillus subtilis and Aspergillus oryzae did not survive at detectable levels when treated with more than 100 ppm of GFSE. The minimum inhibitory concentrations of GFSE for a wide variety of pathogenic and putrefactive bacteria, fungi and yeasts were 100 ppm and 250 ppm, respectively. In the comparable electron micrograph of microbial cells treated with GFSE or not, we could conclude that GFSE destroy microorganisms by disrupting the functions of the cell wall membrane and microbial spores.

Grapefruit extract rich in functional substances adjusting pH 5.0 and adding sucrose (final concentration, 2%) was fermented by Leuconostoc mesenteroides CJNU 0147 strain, consequently prepared a fermented grapefruit extract containing dextran. As a result of analyzing the growth inhibitory effect on gut harmful bacterium Clostridium difficile strain using the prepared fermented grapefruit extract, the viable cell count was significantly reduced (p<0.05 vs. control for 0.5 brix as a final concentration; p<0.001 vs. control for 1.0 brix). On the other hand, the proliferative ability of the extract for Bifidobacterium breve strain, which is one of the species of the genus Bifidobacterium well known as human gut beneficial bacteria, was confirmed (p<0.001 vs. control for both 0.5 and 1.0 brix). These results indicate fermented grapefruit extract with Leu. mesenteroides CJNU 0147 strain inhibits the growth of gut harmful bacterium C. difficile and promotes the proliferation of beneficial bacterium B. breve and is expected to be used as a functional food material for gut health.

Long-term ultraviolet (UV) exposure accelerates the phenomenon of skin photo-aging by activating collagenase and elastase. In this study, we aimed to investigate the effects of a combination of grapefruit and rosemary extracts (cG&Re) on UVB-irradiated damage in HaCaT cells and dorsal mouse skin. In HaCaT cells, cG&Re recovered UVB-reduced cell viability and inhibited protein expression of mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinases (p-Erk), c-Jun N-terminal kinases (p-JNK), and a class of MAPKs (p-P38). Also, cG&Re suppressed UVB-induced collagen and elastin degradation by decreasing matrix metalloproteinases (MMPs) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB) expression, which is a transcription factor. Similar results were observed in dorsal mouse skin. Taken together, our data indicate that cG&Re prevent UVB-induced skin photo-aging due to collagen/elastin degradation via activation of MAPKs, MMPs, and the NF-κB signaling pathway in vitro and in vivo.

Ultraviolet (UV) radiation is associated with the development of extrinsic skin aging. We performed in vivo assays in order to investigate the protective effect of a combination of grapefruit and rosemary extracts (cG&Re) on UVB-induced skin aging. The results indicated that cG&Re displayed elastase inhibitory activity in a dose-dependent manner. Topical application of cG&Re mitigated photo-aging related lesions such as skin erythema and thickening in photo-aged BALB/c mice dorsal skin, by preventing UVB-induced collagen degradation. Immunohistochemical analyses revealed that cG&Re stimulated SIRT-1 expression, and suppressed MMP-1 and IL-1β expression. It was observed that expression of MMP-1 and -13 mRNA was downregulated in the cG&Re-treated group. Furthermore, cG&Re treatment drastically suppressed protein expression of MMP-1 and regulated the phosphorylation of p-38 kinase. As expected, oral administration of cG&Re resulted in the same SIRT-1, MMP-1, and IL-1β expression patterns observed upon topical application of cG&Re in the UV-induced mice model. Overall, the current results demonstrated that cG&Re attenuated both the downregulation of MMP-1 expression and up-regulation of SIRT-1 expression, as well as decreased phosphorylation of MAPK in UVB-induced skin ageing mice model, suggesting that cG&Re might be used as an internal food ingredient for beauty-purposes as well as a functional food material.

The volatile flavor components of the fruit pulp and peel of orange (Citrus sinensis) and grapefruit (Citrus paradisi) were extracted by simultaneous distillation-extraction (SDE) using a solvent mixture of n-pentane and diethyl ether (1:1, v/v) and analyzed by gas chromatography-mass spectrometry (GC-MS). The total volatile flavor contents in the pulp and peel of orange were 120.55 and 4,510.81 mg/kg, respectively, while those in the pulp and peel of grapefruit were 195.60 and 4,223.68 mg/kg, respectively. The monoterpene limonene was identified as the major voltile flavor compound in both orange and grapefruit, exhibiting contents of 65.32 and 3,008.10 mg/kg in the pulp and peel of orange, respectively, and 105.00 and 1,870.24 mg/kg in the pulp and peel of grapefruit, respectively. Limonene, sabinene, α-pinene, β-myrcene, linalool, (Z)-limonene oxide, and (E)-limonene oxide were the main volatile flavor components of both orange and grapefruit. The distinctive component of orange was valencene, while grapefruit contained (E)-caryophyllene and nootkatone. δ-3-Carene, α-terpinolene, borneol, citronellyl acetate, piperitone, and β-copaene were detected in orange but not in grapefruit. Conversely, grapefruit contained β-pinene, α-terpinyl acetate, bicyclogermacrene, nootkatol, β-cubebene, and sesquisabinene, while orange did not. Phenylacetaldehyde, camphor, limona ketone and (Z)-caryophyllene were identified in the pulp of both fruits, while α-thujene, citronellal, citronellol, α-sinensal, γ-muurolene and germacrene D were detected in the peel of both fresh fruit samples.

자몽종자추출물(GSE)이 다른 농도(0, 0.6, 1.0%)로 첨가된 젤라틴 필름을 제조하여 필름의 물성과 딸기의 포장 효과를 각각 조사하였다. GSE의 농도가 증가함에 따라 젤라틴 필름의 신장률은 증가하였으나 인장강도는 대조구의 46.39 MPa에서 1.0% GSE 함유 젤라틴 필름 경우에 31.96 MPa로 감소하였고, 필름의 투습도는 GSE의 농도에 의해 영향을 받지 않았다. GSE 1.0%가 함유된 젤라틴 필름은 E. coli O157:H

Response surface methodology (RSM) is frequently used for optimization studies. In the present work, RSM was used to determine the antimicrobial activitiesof grapefruit seed extract (GFSE) and a lactic acid mixture (LA) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Pseudomonas fluorescens, and Vibrio parahaemolyticus. A central composite design was used to investigate the effects of independent variables on dependent parameters. One set of antimicrobial preparations included mixtures of 1% (w/w) GFSE and 10% (w/w) LA, in which the relative proportions of component antimicrobials varied between 0 and 100%. In further experiments, the relative proportions were between 20% and 100%. Antimicrobial effects against various microorganisms were mathematically encoded for analysis. The codes are given in parentheses after the bacterial names, and were S. aureus (), B. cereus (), E. coli (), S. typhimurium (), P. fluorescens (), and V. parahaemolyticus (). The optimum antimicrobial activity of the 1% (w/w) GFSE:10% (w/w) LA mixture against each microorganism was obtained by superimposing contour plots ofantimicrobial activities on measures of response obtained under various conditions. The optimum rangesfor maximum antimicrobial activity of a mixture with a ratio of 1:10 (by weight) GFSE and LA were 35.73:64.27 and 56.58:43.42 (v/v), and the optimum mixture ratio was 51.70-100%. Under the tested conditions (a ratio of 1% [w/w] GFSE to 10% [w/w] LA of 40:60, and a concentration of 1% [w/w] GFSE and 10% [w/w] LA, 70% of the highest value tested), and within optimum antimicrobial activity ranges, the antimicrobial activities of the 1% (w/w) GFSE:10% (w/w) LA mixture against S. aureus (), B. cereus (), E. coli (), S. typhimurium (), P. fluorescens (), and V. parahaemolyticus () were 24.55, 25.22, 20.20, 22.49, 23.89, and 28.04 mm, respectively. The predicted values at optimum conditions were similar to experimental values.

자몽종자 추출물(GSE)을 0.02, 0.05, 0.08, 0.1%의 농도로 첨가하여 제조한 gelatin 필름의 물성과 항균효과에 대해 조사하였다. 필름의 인장강도는 0.1% GSE를 첨가하였을 경우 10.28 MPa로 대조구의 8.68 MPa에 비하여 1.60 MPa 증가하였으나, GSE 첨가량의 증가에 따라 유의적으로 증가하지는 않았다. 투습계수는 GSE의 첨가량이 증가할수록 감소되는 것을 확인할 수 있었는데, 대조구의 2.48 ngm/m2