• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.21
• /
• pp.9517-9522
• /
• 2014

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and flavonoids, while the hexane extracts contained large amount of tocols and ${\gamma}$-oryzanol. None of the extracts were mutagenic in Salmonella typhimurium strains TA98 and TA100. The hexane extract of rice hull and the methanol extract of rice seed were strongly effective against aflatoxin B1- and 2-amino-3, 4 dimethylimidazo (4, 5-f) quinoline-induced mutagenesis, while aqueous extracts showed weakly antimutagenic properties. All extracts with the exception of aqueous extracts enhanced the number of revertant colonies from benzo (a) pyrene induced-mutagenesis. None of the extracts inhibited mutagenesis induced by the direct mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and sodium azide. The hull extracts showed more potent antimutagenicity than the seed extracts. Based on a chemical analysis, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the hull and cyanidin-3-glucoside and peonidin-3-glucoside in the seed are candidate antimutagens in purple rice. The antimutagenic mechanisms of purple rice might be related to either modulation of mutagen metabolizing enzymes or direct attack on electrophiles. These findings supported the use of Thai purple rice as a cancer chemopreventive agent.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.11
• /
• pp.6541-6548
• /
• 2013

Pigmented rice is mainly black, red, and dark purple, and contains a variety of flavones, tannin, polyphenols, sterols, tocopherols, ${\gamma}$-oryzanols, amino acids, and essential oils. The present study evaluated the cytotoxic effects of purple rice extracts (PREs) combined with chemotherapeutic drugs on human cancer cells and mechanisms of cell death. Methanolic (MeOH) and dichloromethane (DCM) extracts of three cultivars of purple rice in Thailand: Doisaket (DSK), Nan and Payao (PYO), were tested and compared with white rice (KK6). Cytotoxicity was determined by 3-(4, 5-dimethyl)-2, 5-diphenyltetrazolium bromide (MTT) assay in human hepatocellular carcinoma HepG2, prostate cancer LNCaP and murine normal fibroblast NIH3T3 cells. MeOH-PYO-PRE was the most cytotoxic and inhibited HepG2 cell growth more than that of LNCaP cells but was not toxic to NIH3T3 cells. When PREs were combined with paclitaxel or vinblastine, they showed additive cytotoxic effects on HepG2 and LNCaP cells, except for MeOH-PYO-PRE which showed synergistic effects on HepG2 cells when combined with vinblastine. MeOH-PYO-PRE plus vinblastine induced HepG2 cell apoptosis with loss of mitochondrial transmembrane potential (MTP) but no ROS production. MeOH-PYO-PRE-treated HepG2 cells underwent apoptosis via caspase-9 and-3 activation. The level of ${\gamma}$-oryzanol was highest in DCM-PYO-PRE (44.17 mg/g) whereas anthocyanin content was high in MeOH-PYO-PRE (5.80 mg/g). In conclusion, methanolic Payao purple rice extract was mostly toxic to human HepG2 cells and synergistically enhanced the cytotoxicity of vinblastine. Human HepG2 cell apoptosis induced by MeOH-PYO-PRE and vinblastine was mediated through a mitochondrial pathway.

• Nutrition Research and Practice
• /
• v.12 no.5
• /
• pp.365-370
• /
• 2018

BACKGROUND/OBJECTIVES Oxidative stress is a major cause of cancer. This study investigated the effects of the ethanol extracts from germinated and non-germinated Keunnunjami rice, a blackish-purple pigmented cultivar with giant embryo, on selected human cancer cell lines and on the antioxidant defense system of mice fed with a high-fat diet. MATERIALS/METHODS: High fat-fed mice were orally administered with either distilled water (HF) or extracts (0.25%, w/w) from brown (B), germinated brown (GB), Keunnunjami (K), and germinated Keunnunjami (GK) rice. RESULTS: In comparison with the brown rice extract, Keunnunjami extract showed higher anticancer effect against cervical and gastric cell lines but lower anticancer activity on liver and colon cancer cells. Mice from the HF group showed significantly higher lipid peroxidation and lower antioxidant enzyme activities than the control group. However, the oxidative stress induced by high-fat diet markedly decreased in B, GB, K, and GK groups as compared with the HF group. CONCLUSIONS: Germination may be an effective method for improving the anticancer and antioxidative properties of Keunnunjami rice and extracts from germinated Keunnunjami rice may serve as a therapeutic agent against cervical and gastric cancers and oxidative damage.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.45 no.4
• /
• pp.257-260
• /
• 2000

The content of anthocyanin, cyanidin 3-glucoside (C3G) and the peonidin 3-glucoside (P3G) from 591 rice cultivars and the antioxidative activities of MeOH extract from 8 rice cultivars were evaluated. Among them, C3G content of pigmented rice were ranged from 0 to 451.9mg in 100 g brown rice, while the P3G contents were in the range from 0 to 42.7mg in 100g brown rice. There was no correlation between C3G and P3G content. Total anthocyanin content ranged from 0 to 475.1mg in 100g brown rice. The antioxidative activity, the scavenging activity on DPPH (2,2-diphenyl-picryl-hydrazyl) radical of MeOH extracts from rice grain, were different according to cultivars. The activity of blockish purple pericarp rice cultivars was twice stronger than that of white pericarp cultivar. Especially, the antioxidative activity of Heugjinjubyeo was four times stronger than that of white pericarp cultivar. The scavenging effect on DPPH radical in rice extracts was related to the total anthocyanin contents of the extracts.

• Biomedical Science Letters
• /
• v.17 no.1
• /
• pp.55-60
• /
• 2011

Skin is a physical barrier against diverse injury and damages. Exposure to ultraviolet (UV) radiation causes detrimental skin injuries such as inflammation and cell death. The value of natural pigments could be applied to many usages including cosmetics. This study was conducted to examine the protective effect of natural pigments extracted from mulberry, balsam pear, purple-colored sweet potato, pehmannia root, gardenia fruit, and black rice against UV-induced cell death in HaCaT cells, human keratinocyte cell lines. In the present study, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr induced cell death in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In addition, the exposure of 50 mJ/$cm^2$ UV-B for 24 hr also increased lipid peroxide (LPO) formation, compared to control in HaCaT cells, which was prevented by the pretreatment of extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice. In conclusion, the extracts of mulberry, balsam pear, purple-colored sweet potato, rehmannia root, gardenia fruit, and black rice prevented the UV-B-induced cell apoptosis via the inhibition of oxidative stress in HaCaT cells.

• Korean Journal of Breeding Science
• /
• v.43 no.4
• /
• pp.297-303
• /
• 2011

In order to confirm the biological activities of rice bran and hull, total phenolic content, antioxidant and anticancer activities were examined in three rice varieties that have different seed coat colors such as brown, black, and purple. The antioxidant activity was measured by free radical scavenging assay including DPPH, $ABTS^+$ and reducing power activity. The anticancer activity was evaluated by WST assay with human HepG2 cell lines. As the result, Huegjinju, black seed coat rice, showed higher of the total phenolics contents in both bran and hull, than purple Jeojinju and brown Ilpum. In the antioxidant activity, Heugjinju showed the highest among the bran extracts, but the activities of hull extracts were similar in three varieties. In the anticancer activity to HepG2 cell line, the hull extract was 20% higher than that of bran extract in the average of three varieties. The hull extracts of Ilpum and Jeokjinju showed similar anticancer activites about 92%, and that of Heugjinju showed the lowest activity of 30.4%. The anticancer activities of hull extracts in three varieties showed positive correlation with total phenolics contents, DPPH radical scavenging activities and reducing power activities. In conclusion, the rice bran and hull showed potent antioxidant and anticancer activities varied in three varieties that have different seed coat colors.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.59 no.4
• /
• pp.391-397
• /
• 2014

Anthocyanins are water-soluble plant pigments that give rise to the red, purple, or blue colors observed in many crops. Especially purple pigment of colored rice represent biological activities has been an increased interest, due to the functional meal as a staple food. These health benefits have been attributed to antioxidant property of anthocyanin. However, there have been little genetic source for development of new and various colored rice variety. A recently developed new variety, 'Jungmo1020', showed an unique characteristic of blue color of rice grain hull. We identified the pigment petunidin-3-O-glucoside (Pt-3-G) as a major compound with a value of $176.3{\pm}2.3mg/100g$ (68.3%) from 80% MeOH with 1% HCl extracts by UPLC/MS/MS. The content of Pt-3-G in the extracts using a solvent of 100% MeOH with 1% HCl was the highest with the values of $183.8{\pm}2.5mg/100g$. In addition, these extracts showed excellent antioxidatative activities by DPPH and ABTs assay.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.2
• /
• pp.129-135
• /
• 2008

The objectives of this study were to determine antioxidant activity of the methanolic extracts from some specialty rices and to investigate relationships between antioxidant activities and antioxidant contents in the extracts. ABTS (2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)) radical cation scavenging activity, inhibitory effect on lipid peroxidation, chelating activity, reducing power and inhibitory effect on xanthine oxidase have been used to investigate the relative antioxidant activity of the extracts from specialty rices. The concentrations of total polyphenolics, phytic acid, and anthocyanin in the extracts were measured by spectrophotometric methods and vitamin E analysis was carried out by HPLC. The methanolic extracts prepared from black and red rices showed higher antioxidant activities and contained higher antioxidant compounds compared with other rices, apparently due to their intense red-purple color. The correlation coefficient between total polyphenolic content of methanolic extracts and ABTS radical cation scavenging activity, reducing power, and inhibitory effect of xanthine oxidase were 0.9921, 0.9856, and 0.8032, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.51 no.spc1
• /
• pp.107-112
• /
• 2006

Free Radical Scavening and inflammatory of the methanol extracts, which were prepared from 6 difffrent bran of rice, were evaluated to investigate bioactive substances. Among them, the extract of C3GHibyeo and Heugjinjubyeo showed strong DPPH scavening activities (73.25% and 50.38% at 0.4 mg/ml, respectively). The extract of C3GHibyeo and Heugjinjubyeo showed strong thrombin inhibition activities (258.76% and 243.52% inhibition at 5 mg/ml, respectively). The result of antibacterial activity by Zone assay showed that C3GHi rice extract $(250{\mu}g\;and\;500{\mu}g)$ inhibited attachment of Helicobactor pylori on the ATCC48504 and COO1 cell line. But no effect on the SEO cell line. Cytotoxicity of blackish purple rice extract on the H. pylori doesn't showed. These result support a functional superiority of rice-base livelihood, and suggest that the development of healthy food using functional ingredients of rice is possible.

• Food Science and Preservation
• /
• v.17 no.5
• /
• pp.644-651
• /
• 2010

We prepared sikhe (CSE/BR-SH) using corn silk extract and black rice. The pH decreased during saccharification, from pH $5.88{\pm}0.03$ to pH $5.67{\pm}0.02$ after 6 h. However, the brix and reducing sugar contents increased during saccharification of CSE/BR-SH, with the highest levels ($7.6{\pm}0.05$ brix and $4.012{\pm}0.05$ g/l, respectively) being attained at 6 h. Amylase activity increased to 116.12% of control values 1 h after saccharification of CSE/BR-SH, and decreased thereafter. CSE/BR-SH was light purple in color. Soluble phenolic concentration increased markedly from an initial 8.43 g/l to 23.09 g/l at the end of saccharification (6 h), as did DPPH radical-scavenging activity (from an initial 17.3% to 70.98%), Increases were noted in all of ABTS radical-scavenging activity (from 40.25% to 75.32%), reducing power (from 0.241 to 0.682), and ferric reducing antioxidant power (FRAP) (from 0.288 to 1.071).