• Nutrition Research and Practice
• /
• v.10 no.2
• /
• pp.131-138
• /
• 2016

BACKGROUND/OBJECTIVES: Citrus and its peels have been used in Asian folk medicine due to abundant flavonoids and usage of citrus peels, which are byproducts from juice and/or jam processing, may be a good strategy. Therefore, the aim of this study was to examine antioxidant and anti-inflammatory effects of bioconversion of Jeju Hallabong tangor (Citrus kiyomi ${\times}$ ponkan; CKP) peels with cytolase (CKP-C) in RAW 264.7 cells. MATERIALS/METHODS: Glycosides of CKP were converted into aglycosides with cytolase treatment. RAW 264.7 cells were pre-treated with 0, 100, or $200{\mu}g/ml$ of citrus peel extracts for 4 h, followed by stimulation with $1{\mu}g/ml$ lipopolysaccharide (LPS) for 8 h. Cell viability, DPPH radical scavenging activity, nitric oxide (NO), and prostagladin $E_2$ ($PGE_2$) production were examined. Real time-PCR and western immunoblotting assay were performed for detection of mRNA and/or protein expression of pro-inflammatory mediators and cytokines, respectively. RESULTS: HPLC analysis showed that treatment of CKP with cytolase resulted in decreased flavanone rutinoside forms (narirutin and hesperidin) and increased flavanone aglycoside forms (naringenin and hesperetin). DPPH scavenging activities were observed in a dose-dependent manner for all of the citrus peel extracts and CKP-C was more potent than intact CKP. All of the citrus peel extracts decreased NO production by inducible nitric oxide synthase (iNOS) activity and $PGE_2$ production by COX-2. Higher dose of CKP and all CKP-C groups significantly decreased mRNA and protein expression of LPS-stimulated iNOS. Only $200{\mu}g/ml$ of CKP-C markedly decreased mRNA and protein expression of cyclooxygenase-2 in LPS-stimulated RAW 264.7 cells. Both 100 and $200{\mu}g/ml$ of CKP-C notably inhibited mRNA levels of $interleukin-1{\beta}$ ($IL-1{\beta}$) and IL-6, whereas $200{\mu}g/ml$ CKP-C significantly inhibited mRNA levels of $TNF-{\alpha}$. CONCLUSIONS: This result suggests that bioconversion of citrus peels with cytolase may enrich aglycoside flavanones of citrus peels and provide more potent functional food materials for prevention of chronic diseases attributable to oxidation and inflammation by increasing radical scavenging activity and suppressing pro-inflammatory mediators and cytokines.

• 한국생물공학회:학술대회논문집
• /
• 2003.10a
• /
• pp.246-246
• /
• 2003

• Korean Journal of Poultry Science
• /
• v.10 no.2
• /
• pp.97-101
• /
• 1983

A study was conducted to investigate possibility of utilizing dried citrus peel (DCP) as an ingridient of broiler diets. Fresh citrus peels were collected from a citrus processing plant, and were sun-dried and ground. Both chemical analyses and a feeding trial were carried out. DCP was analyzed for proximate nutrients, amino acids and some minerals. In the feeding trial, a total of 192 day-old female broiler chicks of Manor strain was divided into 16 groups of 12 birds each. Each group was fed one of the 4 different levels(0, 2, 4 and 6%) of DCP replacing an equivalent amount of wheat bran in the diet with 4 replications for 6 weeks. Body weight gain, feed intake and feed efficiency of broilers fed different levels of DCP showed no significant differences among treatments. Immediately after termination of the feeding trial, cach bird was examined for shank color using Roche's Egg Yolk Color Fan. Shank color index of birds increased consistently (P＜0.05) as the level of DCP fed increased, indicating that DCP can be used as a source of pigments. It was concluded from the results that DCP could be used up to 6% in place of wheat bran in broiler diets without adverse effects.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.7
• /
• pp.3559-3567
• /
• 2016

Background: In recent years, there has been considerable research on recycling of agro-industrial waste for production of bioactive compounds. The food processing industry produces large amounts of citrus peels that may be an inexpensive source of useful agents. Objective: The present work aimed to explore the phytochemical content, antioxidant, anticancer, antiproliferation, and antigenotxic activities of lemon, grapefruit, and mandarin peels. Materials and Methods: Peels were extracted using 98% ethanol and the three crude extracts were assessed for their total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant activity using DPPH (1, 1-diphenyl-2-picrylhydrazyl). Their cytotoxic and mitogenic proliferation activities were also studied in human leukemia HL-60 cells and mouse splenocytes by CCK-8 assay. In addition, genotoxic/antigenotoxic activity was explored in mouse splenocytes using chromosomal aberrations (CAs) assay. Results: Lemon peels had the highest of TPC followed by grapefruit and mandarin. In contrast, mandarin peels contained the highest of TFC followed by lemon and grapefruit peels. Among the extracts, lemon peel possessed the strongest antioxidant activity as indicated by the highest DPPH radical scavenging, the lowest effective concentration 50% ($EC_{50}=42.97{\mu}g\;extract/mL$), and the highest Trolox equivalent antioxidant capacity (TEAC=0.157). Mandarin peel exhibited moderate cytotoxic activity ($IC_{50}=77.8{\mu}g/mL$) against HL-60 cells, whereas grapefruit and lemon peels were ineffective anti-leukemia. Further, citrus peels possessed immunostimulation activity via augmentation of proliferation of mouse splenocytes (T-lymphocytes). Citrus extracts exerted non-cytotoxic, and antigenotoxic activities through remarkable reduction of CAs induced by cisplatin in mouse splenocytes for 24 h. Conclusions: The phytochemical constituents of the citrus peels may exert biological activities including anticancer, immunostimulation and antigenotoxic potential.

• Food Science and Preservation
• /
• v.10 no.3
• /
• pp.388-393
• /
• 2003

Citrus peel extract was prepared using 70％ ethanol solution by two extraction conditions (20$^{\circ}C$ for 72 hours and 85$^{\circ}C$ for 3 hours). The effect of gamma-irradiation on the changes of physiological activity also investigated at 0, 5, 10 and 20 kGy of absorbed doses. Color characteristics, DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities of the extracts were measured at 41$^{\circ}C$ for 30 days. Color values were different by extraction methods at the initial stage, which heat-extracted sample had lower L$\^$＊/ - but higher a$\^$＊/ - and b$\^$＊/ -values than those extracted at room temperature. Irradiation changed color of the extract lighter by increasing Hunter color L$\^$＊/ - and a$\^$＊/ -values. DPPH radical scavenging, tyrosinase inhibition and nitrite scavenging activities were not affected by either extraction methods or irradiation but significantly reduced by storage time. Therefore, when the cost-effective extraction methods is selected, the citrus peel extracts, which is a major byproduct in citrus processing, could be used as a functional material in various applications.

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

• Korean journal of food and cookery science
• /
• v.27 no.6
• /
• pp.773-781
• /
• 2011

Coffee beans are processed from coffee cherries by either natural, pulped natural, or washing. The aim of the present study was to evaluate the physiochemical and sensory characteristics of espresso coffees processed by different methods. The color of the washed coffee sample presented the highest value of lightness while the natural coffee sample presented the highest value of redness and yellowness. The biggest difference in brewed coffee, whether natural, pulped natural, or washed, was in the TDS content, which was higher in natural coffee and lower in washed coffee. Sensory descriptive analysis and acceptance test for espresso coffee using a 15 cm line scale were carried out by 12 trained panelists. Natural coffee had the highest cherry-like flavor and sweetness taste while washed coffee had the highest citrus flavor and acidity taste. An important attribute of espresso coffee is body, and natural coffee presented strong body while washed coffee presented a low body attribute. In conclusion, significant differences were observed among the three processing methods of green coffee. Pulped natural coffees presented intermediate physiochemical and sensory characteristics compared to washed and natural coffee. Natural coffees are appreciated for their increased body, and washed coffees are appreciated for added citrus flavors and acidity espresso coffee blends.

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

• Applied Biological Chemistry
• /
• v.22 no.1
• /
• pp.28-32
• /
• 1979

Experiments were carried out for finding out a reasonable background of inferior processing quality of Korean citrus fruits of unshiu varieties. The results obtained were as follows. 1. It is considered that the essence of fruit tastes were sweetness and acidity. Their contents were $9.0-10.0^{\circ}Bx$ and 5.3-6.6% (as citric acid) respectively. These indicates that Korean native citrus fruits were inferior in quality. 2. The hesperidin contents were 58mg% in early ripe unshiu varieties, but were low comparatively as 45mg% in late varieties. 3. The portions of fruit peel were high as 25% in Im and Sukcheon unshiu. Therefore these varieties are favorable for long-time storage. The juice extraction rate were 50% on the average with not much difference between varieties. 4. Specific gravity of the extracted juice were 1.040. Vit. C and hesperidin contents of the juice were $25{\sim}30mg%$ on the average in all varieties.

• Food Science and Preservation
• /
• v.19 no.5
• /
• pp.652-658
• /
• 2012

This study, the changes in physicochemical properties and hesperidin content of Jeju-processed citrus fruits according to the harvest date were evaluate. The soluble-solid content, pH, and soluble solid-acid ratios gradually increased, but titratable acidity slightly decreased with a delay in the harvest date. The color index, lightness, yellowness, and turbidity slightly decreased whereas the redness slightly increased with a delay in the harvest date. The hesperidin content slightly decreased with a delay in the harvest date. Hesperidin, which is the major cause of juice cloudiness, decreased with a delay in the harvest date. These results suggest that later-harvested fruit juice is bound to be less cloudy.