• Korean Journal of Food Science and Technology
• /
• v.27 no.3
• /
• pp.342-347
• /
• 1995

Experiments were conducted to investigate the effects of storage temperature and blanching treatment on the storage stability in order to extend the shelf life of Citrus junos. Chilling injury of Citrus junos was not observed at the temperature range of $0^{\circ}C{\sim}5^{\circ}C$. Respiration rate of Citrus junos classified into climacteric characteristics as storage time goes by increase of respiration rate. The $Q_{10}$ value of Citrus junos during storage appeared to have a narrow range of $2.3{\sim}2.4$ The decaying rate increased drastically at $20^{\circ}C$ ranging from 71.4% to 86.5%. It was not much influenced by the pretreatments but by the storage temperature. There was no difference in weight loss between the control and blanching treatment. The weight loss of Citrus junos at $20^{\circ}C$ appeared to be high during the 12 weeks period, and consequently the overall quality of Citrus junos was rapidly decreased. The ratio of brix to acid showed a slow increase for Citrus junos stored at $3^{\circ}C.\;At\;20^{\circ}C$, however, it increased rapidly and then decreased. This phenomenon was mainly due to the relatively high increase of brix, compared to the increase in acid content. Development of browning color in Citrus junos was mainly associated with Citrus junos peel, rather than with Citrus junos pulp.

• Korean Chemical Engineering Research
• /
• v.55 no.5
• /
• pp.723-730
• /
• 2017

The batch experiments by response surface methodology (RSM) have been applied to investigate the influences of operating parameters such as temperature, initial concentration, contact time and adsorbent dosage on 2,4-dichlorophenol (2,4-DCP) adsorption with an activated carbon prepared from waste citrus peel (WCAC). Regression equation formulated for the 2,4-DCP adsorption was represented as a function of response variables. Adequacy of the model was tested by the correlation between experimental and predicted values of the response. A fairly high value of $R^2$ (0.9921) indicated that most of the data variation was explained by the regression model. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. These results showed that the model used to fit response variables was significant and adequate to represent the relationship between the response and the independent variables. The kinetics and isotherm experiment data can be well described with the pseudo-second order model and the Langmuir isotherm model, respectively. The maximum adsorption capacity of 2,4-DCP on WCAC calculated from the Langmuir isotherm model was 345.49 mg/g. The rate controlling mechanism study revealed that film diffusion and intraparticle diffusion were simultaneously occurring during the adsorption process. The thermodynamic parameters indicated that the adsorption reaction of 2,4-DCP on WCAC was an endothermic and spontaneous process.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.10
• /
• pp.1317-1323
• /
• 2009

In the present study, we investigated the anti-proliferation activity of Citrus grandis Osbeck peel (CGP) in HL60 (human promyelocytic leukemia) cells. It was found that 80% ethanol extract of CGP could inhibit the cell growth in a dose-dependent manner ($250{\sim}1,000{\mu}g/mL$), which was associated with morphological changes and apoptotic cell death such as depolarized mitochondrial membrane, formation of apoptotic bodies and increased populations of apoptotic sub-G1 phase. The results indicate that CGP extract inhibits the growth of HL60 cancer cells by the induction of apoptosis, which may be mediated by its ability to change the Bcl family proteins and increase the activation of caspase-3 and PARP. Therefore, it is suggested that CGP has the potential to provide a remarkable natural defense against the proliferation of HL60 cells.

• Applied Chemistry for Engineering
• /
• v.29 no.2
• /
• pp.237-243
• /
• 2018

The surface chemistry of WCK-AC, WCN-AC and WCZ-AC which are activated carbons prepared from waste citrus peel using KOH, NaOH, and $ZnCl_2$ as activating chemicals were investigated. Also the relationships between the adsorption capacities of the target gases such as acetone, benzene and methyl mercaptan (MM) by the prepared activated carbons and the pore characteristics of each activated carbon were examined. According to XPS analysis of the prepared activated carbons, graphite and phenolic were the main surface functional groups of C1, and the sum of phenol, carbonyl and carboxyl groups increased in the order of WCK-AC > WCN-AC > WCZ-AC. The breakthrough curves obtained from the adsorption experiments for the three target gases in the fixed bed adsorption reactor were well simulated by the empirical equations proposed by Yoon and Nelson. The adsorption capacity for acetone, benzene and MM was larger for activated carbons with the larger sum of surface functional groups. The larger the specific surface area and the pore volume of activated carbons and the smaller the pore size, the better the adsorption performance. In particular, the specific surface area was the best criterion for the adsorption performance of activated carbons used in this study.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.2
• /
• pp.187-193
• /
• 2014

This study investigated whether or not Citrus unshiu peel extract (CPE) affects fat accumulation in livers of rats fed an ethanol-containing liquid diet. Initially, male Sprague-Dawley rats were housed individually in stainless steel, wire-bottomed cages with free access to a Lieber-Decarli control liquid diet. Rats were divided by body weight into three groups of eight each: one group of rats was fed the Lieber-Decarli control liquid diet devoid of ethanol (control), another was fed the Lieber-Decarli ethanol diet (ethanol), and third was fed the same ethanol diet except containing CPE. All three groups were fed their respective diets for 6 weeks. Serum and liver lipids were analyzed and liver histology performed. Body weight did not differ among the groups over the 6-wk duration. Histology images showed that CPE administration significantly improved fat accumulation in livers, which was induced by ethanol diet. Serum levels of transaminases and lipids also were reduced by CPE consumption. Taken together, the results indicate that CPE may protect ethanol-induced fatty liver by lowering fat accumulation in both the liver and blood. The protective effects of CPE appear to be due to its phenolic contents.

• Nutrition Research and Practice
• /
• v.12 no.2
• /
• pp.129-134
• /
• 2018

BACKGROUND/OBJECTIVES: Although several recent studies have reported the anti-cancer effects of extracts or components of Citrus unshiu peel, which has been used for various purposes in traditional medicine, the molecular mechanisms for their effects remain unclear. In the present study, the anti-cancer activity of a water-soluble extract of C. unshiu peel (WECU) in MDA-MB-231 human breast carcinoma cells at the level of apoptosis induction was investigated. MATERIALS/METHODS: Cytotoxicity was evaluated using the MTT assay. Apoptosis was detected using DAPI staining and flow cytometry analyses. Mitochondrial membrane potential, reactive oxygen species (ROS) assay, caspase activity and Western blotting were used to confirm the basis of apoptosis. RESULTS: The results indicated that WECU-induced apoptosis was related to the activation of caspase-8, and -9, representative initiator caspases of extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3 accompanied by proteolytic degradation of poly(ADP-ribose) polymerase and down-regulation of the inhibitors of apoptosis protein family members. WECU also increased the pro-apoptotic BAX to anti-apoptotic BCL-2 ratio, loss of mitochondrial membrane potential and cytochrome c release from mitochondria to cytoplasm. Furthermore, WECU provoked the generation of ROS, but the reduction of cell viability and induction of apoptosis by WECU were prevented when ROS production was blocked by antioxidant N-acetyl cysteine. CONCLUSIONS: These results suggest that WECU suppressed proliferation of MDA-MB-231 cells by activating extrinsic and intrinsic apoptosis pathways in a ROS-dependent manner.

• Korean Journal of Poultry Science
• /
• v.42 no.3
• /
• pp.215-221
• /
• 2015

Chicken breast meat samples were injected with marinade solution (salt, sugar, phosphate, monosodium glutamate, and nucleic acid) with or without 2% citrus peel extract (CPE), and then a subset were irradiated with a 1 or 2 kGy electron beam (EB) and/or subjected to high-pressure (HP) at 300 or 400 MPa. The initial total aerobic bacterial (TAB) count of the control sample was 4.57 log CFU/g and reached 7.17 log CFU/g after 3 days of storage at $4^{\circ}C$. The 2 kGy EB reduced the TAB count to 4.61 log CFU/g after 7 days. The 400 MPa HP treatment was also effective in reducing the TAB count, but the effect was slightly less than that noted with the 2 kGy EB. The CPE, in combination with the EB and HP, decreased the TAB count by 1.71 and 1.32 log CFU/g at the initial stage and further decreased the count during storage. The 2 kGy EB and the HP (300 and 400 MPa) increased the thiobarbituric acid-reactive substances value, whereas the CPE did not show an antioxidative effect. The EB and HP caused no difference in the sensory qualities. In contrast, the CPE decreased all sensory qualities tested. Sensory panelists commented that the samples with CPE were not in the "rejection" category but were "unfamiliar" for chicken breast meat. In conclusion, the EB was more effective than HP in improving the microbial quality of marinated chicken breast meat. The use of CPE in the marinade solution may synergistically increase the shelf life; however, it is necessary to develop an appropriate formulation to ensure that the sensory qualities are maintained.

• Journal of agriculture & life science
• /
• v.44 no.5
• /
• pp.81-90
• /
• 2010

This study was conducted to evaluate quality characteristics of citron from Namhae. The physicochemical properties, organic acid, free sugar and aroma components were analyzed and compared with citron harvested in different areas of Namhae (Seolcheon, Changseon and Idong-meyon). Total weight of citron was range of 120.51~176.56 g, total and peel weight of citron cultivated from Changseon were significantly higher than the other citron. The color of peel was not significant in cultivated area. Soluble solids was higher in citron from Changseon and Idong than Seolcheon. Total phenol and flavonoids contents in citron from Idong were higher than the others. Organic acids such as citric acid and malic acid were higher in citron from Changseon. The contents of fructose and glucose in peel and sucrose in pulp were detected higher amount. Major component of aroma profiles in citron from different region of was dl-limonene. It was amount to 57.60% in citron from Idong, 71.02% and 73.04% in citron from Seolcheon and Changseon of all aromatic components. These results were suggested that physicochemical properties and aroma components of citron have some difference by cultivation habit, period, different cultivar and producing areas.

• Korean Journal of Food Science and Technology
• /
• v.54 no.3
• /
• pp.288-296
• /
• 2022

This study aimed to verify the effect of Citrus unshiu peel water extract (CUP) on a mouse model of acute gastritis (AG) induced by HCl/ethanol. Several studies have found that CUP has anti-inflammatory effects. The AG model was induced by oral administration of 150 mM HCl/60% ethanol (550 µL) to all groups except the control group. Also, for drug treatment, sucralfate (10 mg/kg) and CUP (100 or 200 mg/kg) were orally administered for 90 minutes before induction. The effect of CUP treatment was confirmed by gross gastric mucosal damage measurement, and the levels of Glutamic Oxaloacetic Transaminase (GOT), Glutamic Pyruvic Transaminase (GPT), and myeloperoxidase were reduced as well as the levels of oxidative stress biomarkers and their related proteins. In addition, the levels of inflammatory proteins, mediators, and cytokines were significantly downregulated byPI3K/Akt signaling. Taken together, these results show that CUP treatment alleviates AG by regulating PI3K/Akt signaling.

• Korean Journal of Food Science and Technology
• /
• v.54 no.1
• /
• pp.28-34
• /
• 2022

Glioblastoma is the most common primary malignant brain tumor and has an extremely poor prognosis. Glioblastoma stem cells (GSCs) contribute to tumor initiation, recurrence, and resistance to therapy, and are thus a key therapeutic target. The peel of Citrus unshiu Markovich has been used in traditional medicine in East Asia to treat various diseases. In this study, we investigated the anticancer activity and molecular mechanism of the chloroform extract of this natural product (CECU) in U87MG GSCs. The results show that CECU inhibited the proliferation, tumorsphere formation, and migration of U87MG GSCs by causing cell cycle arrest at the G0/G1 phase and apoptosis. In addition, CECU downregulated key cancer stemness regulators, including CD133, Oct4, Nanog, integrin α6, ALDH1A1, and STAT3 signaling in U87MG GSCs. Furthermore, CECU significantly suppressed in vivo tumor growth of U87MG GSCs in a chorioallantoic membrane model. Therefore, CECU can be utilized as a natural medicine for the prevention and treatment of glioblastoma.