• Nutrition Research and Practice
• /
• v.18 no.1
• /
• pp.33-45
• /
• 2024

BACKGROUND/OBJECTIVES: Onion, particularly onion peel, is a quercetin-rich food with, anti-inflammatory and immunomodulatory effects. However, the effect of onion peel extract (OPE) in humans is unclear. Thus, the present study aimed to investigate whether OPE improves natural killer (NK) cell activity and cytokine concentration in a randomized double-blind placebo-controlled trial. SUBJECTS/METHODS: Eighty participants aged 19-64 yrs old with a white blood cell count of 4,000-10,000 cells/µL, symptoms of upper respiratory infection at least once within the previous 12 mon, and perceived stress scale (PSS) over 14 were included. Participants were randomly assigned to take either 1,000 mg/day OPE or a placebo for 8 weeks. RESULTS: Compliance were 87.4 ± 8.6% and 86.9 ± 79.0% in OPE and placebo groups. Compared to the placebo, OPE supplementation improved "Hoarseness" (P = 0.038) of the Wisconsin Upper Respiratory Symptom Survey (WURSS)-21 symptom, and stress scores (P = 0.001; 0.021) of PSS. Supplementation of OPE had no significant effect on NK cell activity and concentrations of cytokines such as interleukin (IL)-2, IL-6, IL-12, IL-1β, interferon-γ, and tumor necrosis factor-α. At baseline, the WURSS-21 symptom and PSS score (P = 0.024; 0.026) were higher in the OPE group than the placebo group. Among participants with higher than median WURSS-21 symptom score, OPE supplementation increased NK cell activity (P = 0.038). Supplementation of OPE had no significant effects on safety measurements and adverse events. CONCLUSIONS: The present study suggested that OPE supplementation improves NK cell activity in participants with moderate upper respiratory symptoms without any significant adverse effects.

• Nutrition Research and Practice
• /
• v.18 no.1
• /
• pp.46-61
• /
• 2024

BACKGROUND/OBJECTIVES: An increasing life expectancy in society has burdened healthcare systems substantially because of the rising prevalence of age-related metabolic diseases. This study compared the effects of animal protein hydrolysate (APH) and casein on metabolic diseases using aged mice. MATERIALS/METHODS: Eight-week-old and 50-week-old C57BL/6J mice were used as the non-aged (YC group) and aged controls (NC group), respectively. The aged mice were divided randomly into 3 groups (NC, low-APH [LP], and high-APH [HP] and fed each experimental diet for 12 weeks. In the LP and HP groups, casein in the AIN-93G diet was substituted with 16 kcal% and 24 kcal% APH, respectively. The mice were sacrificed when they were 63-week-old, and plasma and hepatic lipid, white adipose tissue weight, hepatic glucose, lipid, and antioxidant enzyme activities, immunohistochemistry staining, and mRNA expression related to the glucose metabolism on liver and muscle were analyzed. RESULTS: Supplementation of APH in aging mice resulted in a significant decrease in visceral fat (epididymal, perirenal, retroperitoneal, and mesenteric fat) compared to the negative control (NC) group. The intraperitoneal glucose tolerance test and area under the curve analysis revealed insulin resistance in the NC group, which was alleviated by APH supplementation. APH supplementation reduced hepatic gluconeogenesis and increased glucose utilization in the liver and muscle. Furthermore, APH supplementation improved hepatic steatosis by reducing the hepatic fatty acid and phosphatidate phosphatase activity while increasing the hepatic carnitine palmitoyltransferase activity. Furthermore, in the APH supplementation groups, the red blood cell (RBC) thiobarbituric acid reactive substances and hepatic H₂O₂ levels decreased, and the RBC glutathione, hepatic catalase, and glutathione peroxidase activities increased. CONCLUSIONS: APH supplementation reduced visceral fat accumulation and alleviated obesity-related metabolic diseases, including insulin resistance and hepatic steatosis, in aged mice. Therefore, high-quality animal protein APH that reduces the molecular weight and enhances the protein digestibility-corrected amino acid score has potential as a dietary supplement for healthy aging.

• Clinical Nutrition Research
• /
• v.11 no.1
• /
• pp.62-73
• /
• 2022

An insufficient intake of magnesium may be associated with the development of chronic obstructive pulmonary disease (COPD). We aimed to determine the relationship between health related quality of life (QoL), anthropometric indices and nutritional status with dietary magnesium intake in COPD patients. Sixty-one COPD patients participated in this cross-sectional study. QoL and nutritional status were assessed. Furthermore, body composition, calf circumference, and muscle strength were measured; equations were used to calculate fat-free mass index, body mass index, and muscle mass value. Dietary magnesium intake was assessed by three 24-hours recalls and magnesium intake was categorized as ≤ 188.08 mg/day (A group) and > 188.08 mg/day (B group). The χ², independent-sample t-test and Mann-Whitney test were used for statistical analysis. The p values less than 0.05 were considered significant. Of QoL assessments the total and impact mean scores of St. George's respiratory questionnaire in the B group were significantly lower than the means of the A group (p value = 0.007 and 0.005, respectively). The instrumental activity of daily living score was significantly improved in patients with higher consumption of dietary magnesium (p = 0.02). Participants had a significantly lower mean score of patient-generated subjective global assessment in the B group compared to the A group (p = 0.003). Higher intake of dietary magnesium can lead to improve QoL and nutrition status.

• Journal of Community Nutrition
• /
• v.4 no.2
• /
• pp.99-108
• /
• 2002

Recently interests on raw-food diets are rapidly increasing in relation to chronic diseases prevention in Korea, but studies on raw-food diets have been hardly performed by nutritionists. This study was performed to investigate the effects of low-calorie diets using a raw-food formula in the form of freeze-dried powder on obesity and its complications in the obese women (body mass index (BMI) $\geq$ 25kg/㎡) for eight weeks. Forty premenopausal women (mean BMI 28.04kg/㎡, mean age 28.33years old) participated in this diet intervention, and were controlled by eating 1 regular meal, 1-2 snacks and 2 raw-food formula (140kcal/pack) meals a day within the 1500-1300kcal ranges. Anthropo-mentric measurements, body compositions, physical exercise, and obesity-related risk factors were assessed before (the initial), during (the 4th week) and after (the 8th week) the study. All the data was analyzed by paired t-test, repeated measures ANOVA, and nonparametric rank test at p<0.05 level. Obesity was significantly increased during this study, and it was decreased in weight (-4.59%, p<0.000), BMI (-4.56%, p<0.000), body fat percent (-6.18%, p<0.000), fat mass (-10.19%, p<0.000), waist and hip circumferences(-5.69%, p<0.000 and -2.55%, p<0.000) and WHR (-3.24%, p<0.000). Energy expenditure of physical exercise was increased as much as 70kca1/day during the study (p=0.000), but it did not have any correlations with weight loss and changes of body compositions. Biochemical measurements including blood triglyceride(p <0.006) and leptin(p<0.000) levels were significantly decreased, LDL cholesterol level was increased(p<0.05), but all the blood lipid levels were in the normal ranges. Fatty liver echogenicity and menstrual irregularity were improved after the diet intervention(p<0.000 and p<0.034). In conclusion, this B-week low-calorie diet intervention using raw-food formula was effective for obese premenopausal women in reducing obesity and its risk factors so as not to proceed towards comorbidities. However, the variation of blood lipid levels should be observed for a longer Period.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.12
• /
• pp.1708-1714
• /
• 2011

This study investigated the possible anti-obesity effects of Hypsizigus marmoreus on high fat-fed mice. Thirty male C57BL/6 mice were randomly divided into 3 groups: a normal diet group (N), a high-fat diet group (HF), and a high-fat diet with 5% Hypsizigus marmoreus group (HF-H). After 8 weeks, the body weights in the HF group significantly increased, while those of the HF-H group decreased. Also, liver and adipose tissue weights in the HF-H group significantly decreased. Total serum cholesterol, leptin, and insulin levels were significantly higher in the HF group than those of the N group, but lower than those of the HF-H group. Accumulation of hepatic lipids was apparent in the HF group, as indicated by HE staining and hepatic lipid analysis, while these effects were improved by supplements with Hypsizigus marmoreus in the HF-H group. Also, a reduction in adipocyte size of the epididymal adipose tissue was observed in the HF-H group. $PPAR{\gamma}$, SREBP-1c, and SCD-1 protein expressions were down-regulated in the epididymal adipose tissue of the HF-F group compared to the HF group. Taken together, these results suggest that Hypsizigus marmoreus may an effective anti-obesity treatment.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.3
• /
• pp.425-431
• /
• 2015

Estrogen deficiency is associated with increased body weight and fat mass, resulting in obesity-associated complications such as insulin resistance, cardiovascular disease, and type-2 diabetes. The present study was performed to investigate the effect of black rice (Oryza sativa L.) extracts (BRE) on body weight and fat mass in ovariectomized rats. Ovariectomized (or sham-operated) rats were randomly blocked into three groups (n=8~10 per group): sham operated group (S), ovariectomized control group (OVX), and ovariectomized group with BRE 30 mg/kg B.W. (BRE). High fat diet (fat calories 45%) was fed to all experimental rats for 12 weeks. Final body weight, weight gain, and body fat weight showed significant increases in the OVX group, whereas they were reduced by BRE supplementation. Serum TAG, T-chol level, and adipocyte size were not significantly different among the three groups. However, ovariectomy-induced hepatic steatosis was improved in BRE-treated group. Moreover, in the BRE group, serum leptin levels was significantly lower and fecal total lipid concentrations was significantly higher compared to the OVX group. The gathered data suggest that BRE is a potentially useful ingredient to protect against estrogen deficiency-related obesity and its related diseases.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.2
• /
• pp.236-245
• /
• 2017

Objective: The study was to investigate the effects of alanyl-glutamine (Ala-Gln) and glutamine (Gln) supplementation on the intestinal mucosa barrier in piglets. Methods: A total of 180 barrows with initial weight $10.01{\pm}0.03kg$ were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala)], Ala-Gln diet (0.5% Ala-Gln), Gln diet (0.34% Gln and 0.21% Ala), respectively. Results: The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05), Gln supplementation increased the villi height of jejunum (p<0.05), Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05), raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1) and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05), Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05), Gln increased the number of goblet cells in duodenal epithelium (p<0.05) and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05). Conclusion: These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.7
• /
• pp.934-941
• /
• 2008

Effect of electron beam irradiation (1 and 2 kGy) on apricot was determined in order to develop preservation techniques to enhance shelf-life during 2 weeks at room temperature. Aerobic bacteria and molds/yeasts in apricot were reduced significantly with the increase of irradiation dose. Hardness of apricots decreased during storage by irradiation. Hunter's color value results showed that lightness and redness of irradiated samples were low compared with control samples. Also, sensory test resulting overall acceptability was not significantly different by 1 kGy irradiation during the storage days. Reducing sugar contents was increased gradually, and value of irradiated samples was high compared with non-irradiated sample. Organic acid contents of 2 kGy irradiated samples was not significantly changed during storage. In pH, total sugar, hydrogen donating activity and vitamin C contents, there were no significant differences between treatments. The electron beam treatment on apricots at 1 and 2 kGy did not affect pH, total sugar, hydrogen donating activity and vitamin C contents but improved microbial safety.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.7
• /
• pp.817-823
• /
• 2009

This study was conducted to determine the optimal extraction conditions for maca by comparing the yields, total polyphenol contents, superoxide dismutase (SOD)-like activity and the nitrite scavenging ability. The proximate composition analysis showed 6.57% moisture, 12.83% crude protein, 1.05% crude fat, 4.80% ash and 74.75% carbohydrate. Maca was extracted with 7 different solvents (water, methanol, ethanol, acetone, ethyl acetate, chloroform and hexane) and the extracts were tested for biological activities. The extraction yields of water, methanol and ethanol extracts were 46.2%, 21.4% and 16.8%, respectively. Acetone, ethyl acetate, chloroform and hexane exhibited very low extraction yield, ranging from 0.2 to 1.0%. Total polyphenol contents and the nitrite scavenging ability were the highest in water extract. Electron donating ability and the SOD-like activity were the highest in methanol extract. When water extract was drawn out at different extraction temperatures (30, 70, $100^{\circ}C$) and time (1, 3, 5 hr), the improved biological activities (total polyphenol contents, electron donating ability, SOD-like activity and nitrite scavenging ability) were found in extracts treated at $100^{\circ}C$ for 3 or 5 hrs.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.46 no.6
• /
• pp.744-750
• /
• 2017

Acrylamide is a probable human carcinogen and can be formed during frying of starchy foods. The objective of this study was to investigate the effects of acrylamide reduction in storage potato chips by fermentation of Bacillus subtilis and compare its usefulness with four different cultivars of storage potatoes (Goeun, Atlantic, Saebong, and Jinsun). Potato slices were fermented by B. subtilis at $37^{\circ}C$ for 0, 2, and 4 h and fried at $180^{\circ}C$ for 115 s. The total sugar contents of the fermented potato slices did not change compared to the control. However, reducing sugar contents increased in the fermentation solution containing potato slices. Asparagine contents of Saebong and Jinsun potato slices decreased with fermentation time. Color values of the fermented potato chips were improved compared to those of non-fermented potato chips. The highest $L^*$ value was found in Saebong (57.4), followed by Goeun (56.7), Jinsun (52.5), and Atlantic (48.8) after 4 h of fermentation. Potatoes stored for 240 days generated considerable amounts of acrylamide, ranging from 4.99 to 10.38 ppm, after frying. Four hours of fermentation reduced acrylamide formation in all potato chips. The lowest acrylamide content was found in Saebong (0.77 ppm), followed by Jinsun (1.21 ppm), Goeun (1.76 ppm), and Atlantic (4.09 ppm). In conclusion, fermentation of storage potatoes by B. subtilis can effectively lower acrylamide formation during frying of potato chips.