• Research in Plant Disease
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• v.17 no.3
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• pp.302-310
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• 2011

Elsinoe fawcettii is one of major pathogenic fungi which cause citrus scab diseases, resulting in fruit blemishes that reduce the economic value of fruit. By increasing interest to safe products of crops, the alternative methods of disease control is highly required. We investigated whether the 215 bacterial strains isolated from Jeju Island possess antifungal effect or suppression effect on the symptom development by Elsinoe fawcettii on citrus. Among them, three bacterial strains THJ 609-3, MRL408-3, and TRH423-3 that exhibited antifungal capacity against Elsinoe fawcettii were selected. To illustrate the disease suppression mechanism, pre-inoculation with the selected bacterial strains was carried out whether could suppress the citrus crab on the leaves. The observation with a fluorescence microscope revealed that the selected bacteria could decrease the number of fungal spores. The ratio of germ tube formation was also decreased by the selected bacterial strains at one day after fungus challenge. The strain THJ 609-3 was identified as Pseudomonas putida as a result of analyzing the internal transcript spaces of the rhizobacterial rDNA. The strains MRL 408-3 and TRH 423-3 were identified as Burkholderia gladioli. Our results may be valuable when the selected rhizobacterial strains used as the environment-friendly microbe for biological control on citrus scab caused by Elsinoe fawcettii.

• Journal of Applied Biological Chemistry
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• v.51 no.1
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• pp.7-12
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• 2008

The suitability of CPWs, by-products of the juice industry, was investigated as a source for the production of cosmeceuticals. Four kinds of CPWs, CW, CWE, CWER, and CWEA, were examined for their antioxidant potentials in terms of DPPH radical-scavenging ability for anti-wrinkle applications, inhibition of tyrosinase or melanin production for whitening products, and anti-inflammatory effects to treat various skin diseases such as atopic dermatitis and acne as well as for anti-bacterial activity against acne-inducing pathogens. Of the four extracts, CWER was the most potent tyrosinase inhibitor ($IC_{50}$ value: $109\;{\mu}g/mL$), and CWEA ($IC_{50}:\;167\;{\mu}g/mL$) showed good antioxidative effects. CWE and CWEA samples had dose-dependent inhibitory effects on the melanin production. The cytotoxic effects of the four CPWs were determined by colorimetric MTT assays using human keratinocyte HaCaT cells. Most extracts exhibited low cytotoxicity at $100\;{\mu}g/mL$. These results suggest CPWs are attractive candidates for topical applications on the human skin.

• Journal of Ginseng Research
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• v.6 no.1
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• pp.30-37
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• 1982

This study was conducted to investigate the water vapor permeability of packaging film, Al- foil laminated paper, and sorption properties of dehydrated and powdered foods. The results are as fellows. 1. Absorption rate of each products was greately affeoted by physicochemical properties of foods rather than initial moisture contents of the products. 2. The absorption rate of each products were in the order of freeze dried coffee, spray dried coffee, freeze drie4 ginseng extract, spray dried ginseng extract, ginger tea, black tea, citrus juice Powder and ssang wha tea. 3. Most of the products such as freeze dried coffee, spray dried coffee, freeze dried ginseng extract, ginger tea and black tea have shorter than a month of shelf life. 4. The stability of the products were greatly affected by its desorption properties than the degree of desorption of moisture. 5. Water vapor permeability of packaging materials which are laminated Al-foil with polythylene and glassin paper were mainly affected of thickness of Al-foil and polyethylene.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.166-169
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• 2002

A fruits soft rot caused by Rhizopus stolonifer found on citrus fruit in Jinjn City Agricultural Products Wholesale Market. The disease infection usually started from wounding. At first, the lesions started water soaked and rapidly softened and diseased lesion gradually expanded to other fruits in the same container. The mycelia grew vigorously on the surface of fruits and formed sporangia, sporangiophores and stolons. Sporangiophores were $900{\sim}4300{\mu}m$ in size. Sporangia were globose or subglobose and $98{\times}346{\mu}m$ in size. The color of sporangia was white at first and then turned black with many spores. Columella were globose or ellipsoid and $60{\sim}216{\times}72{\sim}143{\mu}m$ in size. Sporangiospores were globose or ellipsoid, brownish-black streaked and $8{\sim}18.3{\mu}m$ in diameter. Zygospores were globose, black and $98{\sim}176{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was $25^{\circ}C$. The causal fungus was identified as Rhizopus stolonifer. This is the first report of rhizopus soft rot on citrus fruit caused by R. stolonifer in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.617-623
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• 2021

The study was conducted to investigate the dietary supplementation of citrus by-product (CBP) and CBP fermented with Bacillus subtilis (BS) or B. pumilus (BP) on growth performance, feed utilization, innate immune responses and disease resistance of Korean rockfish Sebastes schlegelii. Triplicate groups of juvenile fish (initial weight of 22.9 g) were fed one of five experimental diets which were formulated to replace a synthetic vitamin C (L-ascorbyl-2-polyphosphate, LAPP) with CBP or fermented CBP. A basal diet without LAPP and CBP was used as the control diet (Con). At the end of the 13 weeks feeding trial, growth performance, feed utilization and survival of fish fed the Con were significantly lower than those of fish fed the LAPP, CBP and fermented CBP diets. Fish fed the Con were significantly lower in lysozyme activity than fish fed LAPP, CBP and fermented CBP diets. In a challenge test against Edwardsiella tarda, cumulative mortality of fish fed LAPP, CBP and fermented CBP diets was significantly lower (20-30%) than that of the Con (60%). The findings in this study indicate that the CBP and/or fermented CBP can be a promising vitamin C source for LAPP replacement in diet for Korean rockfish.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.750-755
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• 1996

Citrus juice was treated with supercritical carbon dioxide $(SC-CO_{2})$ and the effect of temperature and pressure on quality of citrus juice was determined. Pectinesterase (PE) was inactivated by $(SC-CO_{2})$ below temperatures necessary for thermal inactivation. There was no significant change in the pH, Brix and total acidity of citrus juice before and after $(SC-CO_{2})$ treatment, but brightness was improved. More ascorbic acid was retained during $(SC-CO_{2})$ treatment of citrus juice than thermal treatment $(93^{\circ}C/0.66\;min)$.During storage of supercritically treated citrus juice at $4^{\circ}C$, activity of PE was reversible. Sensory evaluation showed that color, flavor, taste and overall acceptance of $(SC-CO_{2})$ treated juice were not significantly different from untreated juice. This method offers potentially beneficial processing avenues for citrus juice and other juices, especially in the area of minimally processed products.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1086-1091
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• 2008

The antioxidant activities of the extracts of dangyuja (Citrus grandis Osbeck) leaves were evaluated. The highest phenolic content was obtained from the ethyl acetate fraction (EF) (202.1$\pm$0.8 mg GAE/g dried extract) and it exhibited the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. The cytoprotective effects of EF on oxidative damage induced by tert-butyl hydroperoxide (t-BHP) in a human hepatoma cell line, HepG2 cells, were investigated to understand the intracellular antioxidant mechanisms. Treatment of HepG2 cells with EF prior to oxidative stress was found to inhibit reactive oxygen species (ROS) generation, lipid peroxidation, and DNA damage in a dose-dependent manner. Gas chromatography-mass spectrometry (GC-MS) studies on EF resulted in tentative identification of 19 compounds representing 94.3% of the total content. Taken together, these results demonstrated that EF has excellent antioxidant activities and thus dangyuja leaves have great potential as a source for natural antioxidant which can be applied in food products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.331-337
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• 2015

Citrus and its peels, which are by-products from juice and/or jam processing, have long been used in Asian folk medicine. Citrus peels show an abundant variety of flavanones, and these flavanones have glycone and aglycone forms. Aglycones are more potent than glycones with a variety of physiological functions since aglycone absorption is more efficient than glycones. Bioconversion with cytolase converted narirutin and naringin into naringenin and hesperidin into hesperetin. Therefore, this study aimed to investigate the anti-oxidant and anti-inflammatory effects of bioconversion of Citrus unshiu (CU) peel extracts with cytolase (CU-C) in RAW264.7 cells. HPLC chromatograms showed that CU and CU-C had 23.42% and 29.39% total flavonoids, respectively. There was substantial bioconversion of narirutin to naringenin and of hesperidin to hesperetin. All citrus peel extracts showed DPPH scavenging activities in a dose-dependent manner, and CU-C was more potent than intact CU. RAW264.7 cells were pre-treated with $0{\sim}500{\mu}g/mL$ of citrus peel extracts for 4 h and then stimulated by $1{\mu}g/mL$ of lipopolysaccharide (LPS) for 8 h. All citrus peel extracts showed decreased mRNA levels and protein expression of LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose-dependent manner. Especially, CU-C markedly inhibited mRNA and protein expression of iNOS and COX-2 compared to intact citrus peel extracts. All citrus peel extracts showed decreased NO production by iNOS activity. This result suggests that bioconversion of citrus peel extracts with cytolase may provide potent functional food materials for prevention of chronic diseases attributable to oxidation and inflammation by boosting the anti-inflammatory effects of citrus peels.

• Journal of Life Science
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• v.18 no.10
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• pp.1369-1376
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• 2008

In this study, the effects of feeding citrus byproducts on nutritional components of Korean native chickens were investigated. Two samples of Korean native chickens were used for this study: T0 (chickens fed with only feed for laying hen until they became 39 weeks old, not with citrus byproducts) and T1 (chickens fed with citrus byproducts). The feed for T1 was the same as T0 for the first 16 weeks, and then was made by adding 4% of citrus byproducts to the feed for T0 between $17{\sim}39$ weeks. The chicken used for the experiment was obtained by chilling them for 2 days after slaughter. There was no significant difference between T0 and T1 regardless of feeding citrus byproducts, in terms of their breast/thigh's calorie, contents of moisture, protein, fat and ash, total structural amino acid, total free amino acid and composition of saturated/unsaturated fatty acids. The breast's cholesterol amount of T0 and T1 were 48.4 mg/100 g and 47.6 mg/100 g, respectively, while that of thigh for T0 and T1 were 75.7 mg/100 g and 72.8 mg/100 g, respectively, which implies that T1 showed lower amount of cholesterol than T0. T1 showed significantly higher amount of phosphorus, potassium, magnesium and vitamin B2 for thigh than T0 (p<0.05).

• Journal of Nutrition and Health
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• v.49 no.3
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• pp.144-152
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• 2016

Purpose: This study was conducted in order to develop morning bread using powdered citrus peels and to examine the effect of its several biological activities for 12 weeks in overweight adults ($$BMI{\geq_-}23$$) living in dormitories of Chonbuk National University. Methods: Control bread was prepared using the same formula except for replacing the wheat flour with 3% citrus peel powder. Subjects were classified according to two groups: Intake group of 3% citrus peel powder fortified morning bread (n = 30) and general morning bread (n = 30). Results: The results of our study showed no significant effects of citrus peel powdered morning bread on anthropometric indices and biochemical characteristics among overweight adults. Despite the slight reduction in total-cholesterol, LDL-cholesterol, GOT, and GPT (p < 0.05), no significant differences in changes of these values were observed between the two groups. Conclusion: The short duration of our intervention might have resulted in the lack of any significant effect. Therefore, conduct of further studies with longer duration is warranted in order that the results from this study can be utilized as a basis for the development of food products with citrus peel powder.