• Food Science of Animal Resources
• /
• v.32 no.2
• /
• pp.190-197
• /
• 2012

This study was performed to evaluate the extraction method (Yacon ethanol extracts; YEE, Yacon pressed extracts; YPE) and various levels (0.05-1.0%) of Yacon (Polymnia sonchifolia) on antioxidant and antimicrobial activities. In linoleic acid emulsion of YPE, there were higher iron chelation activity and antioxidant activity than those of YEE (p<0.05). A 1,1- diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity and reducing power of both extracts showed a higher rate at 0.5% level. Ground pork patties, which contain 0.5% YEE and YPE, were manufactured and BHT (0.01%) was used as a reference. Physicochemical properties and microbial counts of ground pork patties, containing a different type of Yacon, were evaluated during the 14 d of storage at $4^{\circ}C$. A pH level, and lightness (Hunter L), as well as the yellowness (Hunter b) values of treatments were not different from those of the control (p>0.05), but increased during storage, at $4^{\circ}C$. Lightness values of ground pork patties, with Yacon extracts, showed the highest. TBARS value of ground pork patties that contains Yacon increased with increased storage at $4^{\circ}C$ (p<0.05), and pork patties with YPE or YEE retarded the lipid oxidation, during refrigerated storage, as compared to that of the CTL. Thus, YPE could be used as a potential possibility to inhibit the lipid oxidation of processed meats, during the refrigerated storage.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.1
• /
• pp.35-41
• /
• 2003

The study was conducted to develope a rapid method for the detection of Yersinia enterocolitica in spring water and vegetables via multiplex polymerase chain reaction (PCR) technique using ail, yst, uirF and subgenus-specific Y16S primers. Specificity and sensitivity of multiplex PCR and application of best primers for the detection of Y. enterocolitica from spring water and vegetables were investigeted. Y. enterocolitica ATCC 27729 strains gave 356 bP and 200 bp (Y16S) and 134 bp (yst) bands. but Y. enterocolitica ATCC 9610 and ATCC 23715 strains gave 200 bp and 134 bp bands.In the meanwhile, non-pathogenic Yersinia species, such as Y. frederikseni, Y. inter-media, Y. kristenseni and Y. pseudotuberculosis gave only single 200 bp band, and other bacteria including Escherichia coli O157:H7 ATCC 25392, Shigella dysenteri. Staphylococcu aureus ATCC 25923 and Listeria mo-nocytogenes ATCC 19111 did not show any bands. Among primers, yst and Y16S primer showed the best sensitivity. Seven CFU/mL Y. enterocolitica cells could be detected with yst and Y16S primers and the sensitivity was significantly improved by the further 2nd PCR after 38 cycles of first PCR amplication. Spring water, cabbage and mushroom were inoculated with Y. enterocolitica to determine the sensitivity of multiplex-PCR for the rapid detection of Y. enterocolitica. Multiplex-PCR assay could detect 7 or 70 cells in spring water and vegetables using whole cell lysate with repeating PCR amplication.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.8
• /
• pp.1310-1317
• /
• 2003

Effects of dietary cholesterol and/or taurine supplementation on plasma and hepatic lipid peroxidation status and antioxidant enzyme activities were evaluated in rats fed one of the following semisynthetic diets for 5 weeks: control diet (CD, cholesterol-free and taurine-free diet); high cholesterol diet (HCD, CD+1.5% cholesterol): high taurine diet (HTD, CD+1.5% taurine): high cholesterol and high taurine diet (HCHTD, HCD + 1.5% taurine). Plasma malondialdehyde (MDA) level was not influenced by dietary cholesterol or taurine supplementation, while hepatic MDA level was 70% higher in rats fed HCD compared to the value for CD rats (p<0.05). Our observation that taurine supplementation significantly decreased the hepatic MDA level of rats fed HCD, but failed to decrease lipid peroxidation of rats fed CD indicates that the protective effect of taurine in the liver against lipid peroxidation is manifested only under the hypercholesterolemic environment. Plasma and hepatic glutathione peroxidase (GSH-Px) activities were not affected by dietary supplementation of cholesterol or taurine. However, hepatic superoxide dismutase (SOD) activity was significantly reduced by dietary taurine supplementation (p <0.05), and thus significantly lower in rats fed HTD compared to the value for CD (p<0.05). Plasma total cholesterol concentration was positively correlated with hepatic cholesterol concentration as expected (r=0.712, p<0.001). Plasma (r=0.399, p<0.05) and hepatic cholesterol levels (r=0.429, p<0.05) showed a significantly positive correlation with hepatic MDA concentration, respectively. Plasma taurine concentration was negatively correlated with hepatic SOD activity (r=-0.481, p<0.01), and tended to be negatively correlated with hepatic GSH-Px activity without showing statistical significance (r=-0.188, p<0.05). These results indicate an antioxidative effect of taurine in rats with elevated level of lipid Peroxidation due to high intake of dietary cholesterol. Future application of taurine as a safe candidate for a hypolipidemic agent without adversely affecting body's antioxidant defense system is speculated.

• Korean Journal of Plant Resources
• /
• v.28 no.4
• /
• pp.382-390
• /
• 2015

Momordica charantia L. is a valuable food and medicinal plant of the gourd family (Cucurbitaceae) that is cultivated in tropical and subtropical regions of the world. Physicochemical properties of M. charantia based on cultivars, parts and growing stage were investigated. Crude protein contents of leaf were 27.5%, 26.9%, and 23.6% in native leaf (NL), cv. Erabu leaf (EL), and cv. Dragon leaf (DL), respectively. In particular, the crude protein content was the highest in leaves. The crude fat content was in the order of developmental stage 1 of cv. Erabu fruit (EF1) and developmental stage 1 of native fruit (NF1) with values of 4.0%, and 3.9%, respectively. There was also high amount of crude fiber in stem of all three cultivars. The crude ash content was in the order of cv. Erabu leaf, cv. Dragon leaf, and developmental stage 3 of native fruit (NF3) with values of 23.2%, 17.4%, and 13.6%, respectively. The major minerals found in M. charantia were K, Ca, and Mg. The potassium contents of developmental stage 3 of native fruit (NF3), developmental stage 3 of cv. Dragon fruit (DF3), cv. Dragon stem (DS), and developmental stage 2 of native fruit (NF2) were 498.37, 339.21, 314.30, and 307.34 ㎎ /100g, respectively, while the calcium contents were decreased of EL, DL, and NL with values of 513.45, 371.69, and 209.43 ㎎/100g, respectively. The calcium content was higher in leaves and stems than fruits. On the otherhand, the highest magnesium content was measured in EL (69.92 ㎎/100g). The highest contents of chlorophyll a, chlorophyll b, and total chlorophyll were found in NL (442.9 ㎎/100g dw), EL (759.6 ㎎/100g dw), and EL (1164.9 ㎎/100g dw), respectively. The vitamin C contents from developmental stage 2 of cv. Erabu fruit (EF2), NF3, developmental stage 3 of cv. Erabu on fruit (EF3), and NF2 were found with values of 2849.9, 2330.5, 1985.1, and 1844.5 ㎎/㎏, respectively, and found to be higher in Korean cultivar and Erabu fruit than in Dragon. The charantin contents of leaf were higher than the fruit found to be 547.71, 506.04 and 395.62 ㎍/g dw in DL, EL and EF2, respectively. According to the results, mineral contents, total chlorophyll and charantin contents of M. charantia were higher in the leaves (EL and DL) than the fruits. And, vitamin C content was the highest in the fruit (EF2 and EF3). Therefore, much more research needs to be undertaken to use of the leaves as well as fruits. The data showed that M. charantia can be considered a good source of nutrient for application in food system.

• Korean Journal of Food Science and Technology
• /
• v.40 no.2
• /
• pp.123-128
• /
• 2008

The MRLs (maximum residue limits) of DDT (DDD and DDE) in fresh ginseng, dried ginseng, and steamed red ginseng are set as low as 0.01 mg/kg, 0.05 mg/kg, and 0.05 mg/kg, respectively. Therefore, this study was undertaken to develop a simple and highly sensitive analysis method, as well as to reduce interfering ginseng matrix peaks, for the determination of DDT isomers (o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT, and p,p'-DDT) in fresh ginseng, dried ginseng, and steamed red ginseng at the 0.01 mg/kg level. The method used acetonitrile extraction according to simultaneous analysis, followed by normal-phase Florisil solid-phase extraction column clean-up. The purification method entailed the following steps: (1) dissolve the concentrated sample extract in 7 mL hexane; (2) add 3 mL of $H_2SO_4$; (3) vigorously shake on avortex mixer; (4) cetrifuge at 2000 rpm for 5 min; (5) transfer 3.5 mL of the supernatant to the Florisil-SPE (500 mg/6 mL);and (6) elute the SPE column with 1.5 mL of hexane and 10 mL of ether/hexane (6:94). The determination of DDT isomers was carried out by a gas chromatography-electron capture detector (GC-${\mu}$ECD). The hexane and ether/hexane (6:94) eluate significantly removed chromatographic interferences, and the addition of 30% $H_2SO_4$ to the acetonitrile extract effectively reduced many interfering ginseng matrix peaks, to allow for the determination of the DDT isomers at the 0.01 mg/kg level. The recoveries of the 6 fortified (most at 0.01 mg/kg) DDT isomers from fresh ginseng, dried ginseng, and steamed red ginseng ranged from 87.9 to 99.6%. The MDLs (method detection limits) ranged from 0.003 to 0.009 mg/kg. Finally, the application of this method for the determination of DDT isomers is sensitive, rapid, simple, and inexpensive.

• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.862-870
• /
• 1998

This study shows the application of Ci-ELISA method for monitoring the denaturation of myosin by the frozen treatment in order to differentiate thawed beef from chilled. Hanwoo M.Semitendinosus (n=25) was treated under the two different frozen process as follows; simple frozen treatment (Exp-1) at 4 different temperatures, -10, -20, -50 and $-80^{\circ}C$, respectively, and repeated thawing-refreezing treatment (Exp-2) stored at 4 different temperatures, -10, -20, -50 and $-80^{\circ}C$, respectively. Antibodies (Abs) were produced from rabbits immunized with myosin whole molecule (MWM) isolated from beef round, heavy meromyosin S-1 (S-1) and light meromyosin (LMM) prepared by digestion of MWM. Each immunoglobulin G (IgG) was separated from antiserum. At 6 month storage, IA of anti-MWM IgG for myosin was decreased to 32.67, 32. 23, 51.52 and 34.27% in Exp-1 and to 14.82, 15.61, 25.3 and 23.7% in Exp-2 at -10, -20, -50 and $-80^{\circ}C$, respectively (P<0.05). In Exp-1, the reactivities of anti-LMM IgG were decreased to 25.12, 21.42, 49.05 and 28.96%, and those of Exp-2 were to 11.88, 9.56, 20.63 and 12.64% at -10, -20, -50 and $-80^{\circ}C$, respectively, at 6 times thawing (P<0.05). Conclusively, myosin was denaturated by freezing treatment and LMM or myosin rod part might have suffered from more extreme demage than HMM S-1, and samples at $-50^{\circ}C$ were slightly injured less than others by freezing treatment.

• Journal of Food Hygiene and Safety
• /
• v.34 no.4
• /
• pp.340-347
• /
• 2019

We performed a safety survey on residual pesticides in dried agricultural products. A total of 110 samples of dried agricultural products distributed in Gyeonggi-do were analyzed for 263 pesticides according to multi class pesiticide multiresidue method. Ten types of pesticides were detected in 10 samples. Chlorpyrifos was detected in Ricinus communis leaves, chlorpyrifos, hexaconazole, pyridalyl in Chwinamul (wild aster), diniconazole, isoprothiolane, lufenuron in radish leaves, hexaconazole in Cirsium setidens (Korean thistle), bifenthrin, and chlorothalonil, boscalid, and pyraclostrobin in pepper leaves. The detection rate of pesticides was 9.1%, and among these samples, one was detected over Maximum Residue Limits (MRLs). In the validation study, the values of limit of detection (LOD), limit of quantitation (LOQ), coefficient of determination ($R^2$) and recovery were in the range of 0.002~0.027 mg/kg, 0.006~0.083 mg/kg, 0.9964~1.0000 and 74.8~118.9%, respectively. The Positive List System (PLS) was newly introduced as part of the safety management of residual pesticide in agricultural products in Korea in 2019. With the application of the PLS, if the MRL is not established, 0.01 mg/kg limit is applied uniformly. In spite, these of strengthened residue limits, the MRLs of dried agricultural products are still insufficient. Therefore, this study could be utilized as basic data for the setting of proper MRLs.

• Korean Journal of Microbiology
• /
• v.54 no.4
• /
• pp.384-397
• /
• 2018

The aim of this study is to screen the strains of Bacillus spp. possessing safety, probiotic activity, and so on, which can be utilized as probiotic resource for using the feed and supplement food of companion animal. About 300 isolates were isolated from traditional Korean sauces, four isolates that did not have or produce the six kinds of B. cereus type vomiting and diarrhea toxin genes, ${\beta}$-hemolytic, and three kinds of carcinogenic enzymes were selected. Antibiotic gene retention, cell surface hydrophobicity, antibiotic sensitivity, and glucose utilization were analyzed for four isolates, and finally SRCM 100731 was selected. SRCM 100731 was named as Bacillus amyloliquefaciens SRCM 100731 16S rRNA sequencing analysis, and carried out optimization of cell growth for industrial applications such as pet food and feed. The effects of 14 different components on cell growth were investigated and three significant positive factors, molasses, sodium chloride, and potassium chloride were selected as the main factors based on a Plackett-Burman design. In order to find out optimal concentration on each constituent, we carried out central composite design. The predicted optimized concentrations were 7% molasses, 1.1% sodium chloride, 0.5% potassium chloride. Finally, an overall about 7-fold increase in dry cell weight yield ($12.6625{\pm}0.0658g/L$) was achieved using the optimized medium compared with the non-optimized medium ($1.8273{\pm}0.0214g/L$). This research is expected to be highly utilized in the growing pet industry by establishing optimal cultivation conditions for industrial application as well as screening Bacillus amyloliquefaciens SRCM 100731 as probiotic resource for companion animal.

• Journal of Korean Home Economics Education Association
• /
• v.33 no.3
• /
• pp.143-157
• /
• 2021

This study analyzed and verified the effects of a dietary education program for Korean young adults in single-person households. The dietary education program was conducted for five weeks (from November 10 to December 8, 2020) for Korean young adults in single-person households living in Seongbuk-gu, via four face-to-face education sessions and one online education session, including both theoretical lectures and practice. The effect of the dietary education program was analyzed through the Nutrition Quotient (NQ) questionnaire for adults provided by the Korean Nutrition Society, a dietary evaluation checklist questionnaire developed by the researchers, and photovoices. The average of 'Nutrition' score increased from 51.81 to 53.20, but there was no statistically significant difference. However, there was a significant change in the 'Moderation' category (p<0.05). As for the researcher-developed dietary evaluation, the average of the 'Importance' area rose from 3.77 to 3.99, but there was no statistically significant difference. The average of the 'Practice' area rose from 3.03 to 3.57, significant results were found (p<0.05). When the pre-/post-tests were compared by the sub-categories, four elements of 'Importance', i.e., balanced meals and avoided foods, and all five elements of 'Practice' were significantly improved (p<0.05). A total of 200 photovoices were analyzed according to Social Cognitive Theory. As a result of the analysis, the deterrents that help people eat healthy homemade food were 48% environmental factors, 30% behavioral factors, and 22% individual cognitive factors. The deterrents found to hinder participants from eating healthy homemade food were 72% environmental factors and 14% individual cognitive and behavioral factors. The results suggest that the dietary education program for Korean young adults in single-person households can be an effective tool that promotes self-motivation, behavioral changes, and improvements of the surrounding environment.

• Journal of Food Hygiene and Safety
• /
• v.39 no.1
• /
• pp.54-60
• /
• 2024

This study investigated the effectiveness of using pathogens and aqueous acids to reduce the Aspergillus ochraceus and Rhodotorula mucilaginosa contamination in livestock production environments. For this study, 1 mL of each bacterial suspension (10⁷-10⁸ spores/mL) was inoculated on a knife surface, dried at 37℃, and used under each treatment condition. First, to investigate the effect of organic acids, acetic, lactic, and citric acids were used. Subsequently, to select the appropriate concentration, they were prepared at concentrations of 0.5, 1, 2, 3, 4, and 5%, respectively. Accordingly, to further maximize the effect of organic acid treatment, we combined the treatment with ultraviolet light. The two strains showed a significant difference (P<0.05) compared to the initial strain, with a greater than 90% decrease in the concentrations of all organic acids. Consequently, acetic and lactic acids decreased by approximately 5 and 2 log colony forming unit (CFU)/cm², respectively, when treated with ultraviolet light (360 mJ/cm²); however, citric acid decreased by less than 1 log CFU/cm². However, when manufactured with 4% acetic acid, a severe malodor was emitted, making it difficult for workers to use it in a production environment. Accordingly, the optimal treatment conditions for organic acid and ultraviolet light for application were selected as follows: immersion in a 4% lactic acid solution for 1 minute and then, sterilization with ultraviolet light at 360 mJ/cm². Finally, when a pork meat sample was cut with a knife that was finally washed with lactic acid and treated with ultraviolet light, the low level of inoculum transferred from the cleaned knife to the surface of the sample was not detected. In conclusion, using this established method can prevent cross-contamination of the surface of the meat during processing.