• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.397-404
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• 2005

Effects of ${\gamma}$-oryzanol (0.0, 0.1, 0.5, 1.0, 2.0%) addition on physical and chemical properties of yackwa were determined during storage for 6 weeks at $30^{\circ}C$. Acid, peroxide, and thiobarbituric acid (TBA) valves, color, texture, fatty acid compositions, hexanal content, and rancid flavor of yackwa were measured. Acid, peroxide, and TBA values. and hexanal contents of ${\gamma}$-oryzanol-treated groups were significantly lower than those of groups without ${\gamma}$-oryzanol treatment after 6 week (p < 0,05) and showed concentration-dependency, while no significant differences were observed in colors (p > 0.05). Effects of ${\gamma}$-oryzanol on textural characteristics were not consistent. As storage time increased, ratio of unsaturated fatty acids to saturated fatty acids or ${\gamma}$-oryzanol-added groups was higher than that of groups without ${\gamma}$-oryzanol addition. Addition of ${\gamma}$-oryzanol was effective in decreasing hexanal formation. Sensory evaluation showed rancid odor decreased with increasing concentration of ${\gamma}$-oryzanol. These results suggested ${\gamma}$y-oryzanol, as a natural antioxidant, delayed quality decrease of yackwa during storage.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.173-176
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• 2007

${\gamma}-Oryzanol$ is one of the chain breaking antioxidants. Both sterol (triterpene) and phenolic hydroxyl groups in the structure of ${\gamma}-oryzanol$ may be responsible for its antioxidative function. We hypothesize that ${\gamma}-oryzanol$ is more effective in preventing the autoxidation of polyunsaturated fatty acid (PUFA) than the synthetic phenolic compounds in an oil/water (O/W) emulsion system. The antioxidative effectiveness of different concentrations of ${\gamma}-oryzanol$ and synthetic antioxidants was evaluated at different incubation times (0, 4, 8, 16, and 32 h) by measuring both the formation of hydroperoxides and the decomposition product of hydroperoxides (hexanal) in each emulsion system. Overall, the order of effectiveness of various antioxidants for inhibiting the formation of hydroperoxide in the O/W emulsion was: ${\gamma}-oryzanol$> tert-butylhydroquinone (TBHQ)> butylated hydroxytoluene (BHT)> butylated hydroxyanisole (BHA). O/W emulsion with selective lower concentrations of ${\gamma}-oryzanol$ showed better effectiveness than that with higher concentration of synthetic antioxidants. However, the ability of both ${\gamma}-oryzanol$ and synthetic antioxidants to decompose hydroperoxide was similar. ${\gamma}-Oryzanol$ was more effective antioxidant than the synthetic phenolic compounds in preventing the formation of hydroperoxide in the O/W emulsion system.

• KSBB Journal
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• v.32 no.2
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• pp.83-89
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• 2017

Gamma (${\gamma}$)-oryzanol is a substance abundant in rice, which is widely cultivated in Asian countries. In this study, we evaluated the effect of ${\gamma}$-oryzanol treatment on proliferation and apoptosis of AGS human gastric carcinoma cells. AGS cells were treated with ${\gamma}$-oryzanol for 72 h in a dose dependent manner. Treatment of ${\gamma}$-oryzanol (50, 100, and $200{\mu}g/mL$) resulted in decreased AGS cell proliferation and increased number of cells in the sub-G1 population. Additionally, apoptotic cells were investigated by annexin V staining and mitochondrial membrane potential assays. Our results indicated that ${\gamma}$-oryzanol treatment increased the number of annexin V-positive cells and depolarized cells. This demonstrated that ${\gamma}$-oryzanol is effective for the induction of apoptosis in AGS cells. We next examined the expression of promising anticancer drug target molecules, including PTEN and HSP90. We found that treatment of ${\gamma}$-oryzanol induced the expression of PTEN in AGS cells. Under the same treatment conditions, ${\gamma}$-oryzanol reduced the expression of HSP90 in AGS cells. These results suggest that ${\gamma}$-oryzanol-induced apoptosis was accompanied by changes in regulation of PTEN and HSP90 in AGS cells. Taken together, ${\gamma}$-oryzanol could be used as a functional substance for the prevention of gastric cancer.

• Food Science of Animal Resources
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• v.26 no.3
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• pp.331-336
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• 2006

High purity ${\gamma}$-oryzanol was obtained from rice bran and added at 0.05%, 0.10% or 0.20% (w/w) to pork sausages. Sausages containing ${\gamma}$-oryzanol showed higher CIE $L^*\;and\;a^*$ color values than the control (p<0.05). Sausages containing ${\gamma}$-oryzanol had significantly lower hardness and chewiness in textural properties than the control (p<0.05) when determined by Instron testing machine. However, there were no differences in cohesiveness and springiness between the control and the sausages containing ${\gamma}$-oryzanol. Sausages containing >0.05% of ${\gamma}$-oryzanol had significantly lower thiobarbituric acid reactive substances (TBARS) values than the control since 12 days of storage when sausages were aerobically stored at $4^{\circ}C$ for 18 days (p<0.05). Thus, ${\gamma}$-oryzanol may have a potential application for the sausage products to inhibit lipid oxidation when used at >0.05%.

• Journal of Nutrition and Health
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• v.37 no.5
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• pp.347-351
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• 2004

This study was carried out to investigate the supplementary effects of ${\gamma}$-oryzanol extracted from rice bran on lipid metabolism in diabetic mice. We supplied 2 kinds of experimental diets (CO without and GO with 0.2％ ${\gamma}$-oryzanol) to diabetic mice for 8 weeks. Diet intake, body weight, organ weight, contents of serum and hepatic lipid profiles, and fecal lipid levels were measured. Though there was no significant difference in diet intake, body weight change and organ weight between experimental groups, the concentration of serum total cholesterol and hepatic total lipid, total cholesterol and HMG-CoA reductase activity was significantly lower in GO group treated with 0.2％ ${\gamma}$-oryzanol of diet than CO group after supplementary period of experimental diets. And total lipid, triglyceride, total cholesterol, and bile acid levels excreted to feces were significantly higher in GO group than CO group. These results suggest that ${\gamma}$-oryzanol decrease the serum and hepatic lipid levels by lowing HMG-CoA reductase activity or increasing the contents of fecal lipid in diabetic KK mice.

• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.499-504
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• 2012

We analyzed the contents of ${\gamma}$-oryzanol, which is contained in brown rice of the nation rice varieties Chucheong, Heukjinju and Sindongjin, by HPLC. Furthermore we also performed experiments on its biological activity, to prove the effectiveness of rice bran. The contents of ${\gamma}$-oryzanol contained in hulled rice showed 1,587 ppm for Heukjinju, followed by Chucheong(1,038 ppm), and by Sindongjin(472 ppm). In anti-oxidative activity, we performed an experiment, by measuring the radical scavenging activity of DPPH. Heukjinju showed the best effect, and Chucheong showed the worst effect. In cholesterol lowering activity, Heukjinju showed the best activity and Sindongjin showed the worst effect. In anti-bacterial activity as well, Heukjinju showed the best activity, and Sindongjin showed the worst effect. Through these experiments, we compared the contents of ${\gamma}$-oryzanol, which is contained in hulled rice(Chucheong, Heukjinju, Sindongjin). Also, we found the anti-oxidation effect, cholesterol lowering effect, and anti-bacterial activity of the ${\gamma}$-oryzanol extracts. Based on our research, we expect that ${\gamma}$-oryzanol can work as a new drug, or nutritional supplement.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.827-831
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• 2004

This study was carried out to investigate the supplementary effects of ${\gamma}$-oryzanol on the blood glucose level in diabetic mice. We supplied 2 experimental diets (CO without and GO with 0.2% ${\gamma}$-oryzanol) to diabetic mice for 8 weeks. Diet intake, body weight and levels of blood glucose, hemoglobin $A_{lc}$ and insulin were measured. Though there was no significant difference in diet intake between experimental groups, the concentration of fasting blood glucose and blood glucose area from glucose tolerance test in diabetic mice was lower in GO group than CO group during the supplementary period of experimental diets. Hemoglobin Ai, was lower and serum insulin level was higher in GO group than CO group without significance. These results suggest that r-oryzanol decrease the blood glucose level, and ${\gamma}$ -oryzanol produced from residual product of rice may be developed with high value.

• Journal of Food and Nutrition Research
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• v.9 no.1
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• pp.26-31
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• 2021

Functional food ingredients from natural sources are gaining popularity for treating chronic inflammation associated with metabolic diseases (e.g., diabetes, hypertension, and obesity) due to their lower toxicity and no severe side effects. Pigmented rice is a natural food source in Korea commonly consumed in the whole grain form to improve the immune system. In particular, pigmented rice bran contains various nutritional components involved in the immune benefits. Of many nutrients in pigmented rice bran, anthocyanins, gamma-oryzanol, and arabinoxylan have notably shown to enhance natural killer cell activity and reduce pro-inflammatory cytokines. Especially, pigmented rice has higher amounts of anthocyanins and gamma-oryzanol than white rice. In this review, to provide further insight into the immune effects of the pigmented rice, we have focused on the immune benefits of bioactive substances (e.g., anthocyanins, gamma-oryzanol, and arabinoxylan) from pigmented rice compared to white rice. The pigmented rice has potential effects on immunity, and it can be used as a functional food.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5421-5425
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• 2013

Background: To assess the antioxidant effects of gamma-oryzanol on human prostate cancer cells. Materials and Methods: Cytotoxic activity of gamma-oryzanol on human DU145 and PC3 prostate cancer cells was determined by proliferation assay using 3-(4, 5-dimethylthiazol, 2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) reagent. mRNA levels of genes involved in the intracellular antioxidant system, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GSR) were determined by reverse transcription-polymerase chain reaction (RT-PCR). Cancer cell lysates were used to measure lipid peroxidation using thiobarbituric acid reactive substance (TBARS). Glutathione contents of the cell lysates were estimated by the reaction between sulfhydryl group of 5, 5'-dithio (bis) nitrobenzoic acid (DTNB) to produce a yellow-color of 5-thio-2-nitrobenzoic acid using colorimetric assay. Catalase activity was also analysed by examining peroxidative function. Protein concentration was estimated by Bradford's assay. Results: All concentrations of gamma-oryzanol, 0.1-2.0mg/ml, significantly inhibited cell growth in a dose- and time-dependent fashion in both prostate cancer cell lines, DU145 and PC3. Gene expression of catalase in DU145 and PC3 exposed to gamma-orizanol at 0.5mg/ml for 14 days was down regulated, while mRNA of GPX was also down regulated in PC3. The MDA and glutathione levels including catalase activity in the cell lysates of DU145 and PC3 treated with gamma-oryzanol 0.1 and 0.5mg/ml were generally decreased. Conclusions: This study highlighted effects of gamma-oryzanol via the down-regulation of antioxidant genes, catalase and GPX, not cytotoxic roles. This might be interesting for adjuvant chemotherapy to make prostate cancer cells more sensitive to free radicals. It might be useful for the reduction of cytotoxic agents and cancer chemoprevention.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.113-118
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• 1997

Phytochemical analysis on rice bran and its pitch was performed by the tool of TLC, UV- and IR-spetroscopy, so that it was found that they contained ${\gamma}-oryzanol$ and free sterol. GC-MS analysis of free sterol revealed that it was composed of ${\beta}-sitosterol$, campesterol and stigmasterol. Successive phytochemical analysis of ${\gamma}-oryzanol$ revealed that it was composed of ferulic acid ester of triterpene and sterol, respectively. Triterpene moieties of ${\gamma}-oryzanol$ were identified as follows: cycloartanol, cycloartenol, 24-methylenecycloartanol and unknown triterpene; And sterol moieties were found to be identical with free sterols. In addition, characteristic absorption band in UV spectrum (220-340 nm) was exclusively due to ${\gamma}-oryzanol$. Thus, it was suggested that rice brans of nearly all species of Oryza sativa can be quantitatively analyzed by UV absorption spectrometry, even when water soluble pigments was contained in the rice bran.