Bound lipase:an important form of lipase in rice bran (Oryza sativa)

Rice bran residue possessed a steady lipase activity((26.68 ± 3.69)%)after its endogenous lipase was extracted continuously by phosphate buffer solution(PBS)for 24 h. T herefore, the aim of this research was to explore whether there exist any bound lipases in rice bran(Oryza sativa). Three physical treatments(grinding, homogenizing and ultrasound crush)and 6 enzymatic treatments(cellulase, hemicellulase, pectinase, complex cellulase, glucoamylase and α-amylase)were applied to rice bran in order to investigate this bound lipase. The relative catalytic activities of extraction supernatant and residue for pectinase group were(437.63 ± 22.54)% and(159.26 ± 2.12)%, respectively, which were significantly higher(P < 0.05)than other groups. This phenomenon demonstrated that lipase was the most likely to combine with pectin. Molecular simulation proved that pectin could combine with two rice bran lipases(lipase 315 and lipase 308)and cover the catalytic centers so as to prevent the lipases from encountering the substrate and inhibiting their catalytic activities. During combination, pectin could make the lipases more compact and reduce the solvent accessible surface area of lipases, which would make the lipases inactive to molecular interaction. In summary, part of rice bran lipase was proved to exist in bound form and combined with the pectin.

Bioprocessed Black Rice Bran Potentiates the Growth Inhibitory Activity of an Immune Checkpoint Inhibitor against Murine Colon Carcinoma

This study determined the effect of orally fed polysaccharide-rich bioprocessed (fermented) black rice bran produced by culturing with shiitake (Lentinus edodes) mushroom mycelium on CT-26 colon cancer cells in vivo in an intracutaneously transplanted mouse tumor alone and in combination with intraperitoneally administered anti-PD-1 immune checkpoint inhibitor. Analysis of the isolated tumor weights at the end of the study shows that the average tumor size in control mice is 3.78 grams, and the average tumor size in mice treated with anti-PD-1 antibody is 2.16 grams. The average tumor size in mice treated with BRB-F alone is 2.25 grams, and the average tumor size in mice treated with anti-PD-1 antibody BRB-F combination is 1.38 grams. Thus, BRB-F or anti-PD-1 antibody alone each reduce tumor size by 40.5% or 42.9%, whereas the combination of BRB-F and anti-PD-1 antibody reduces tumor size by 63.5%, with their cooperative effect being statistically significant. The observed anti-tumor effects were accompanied by a series of biomarkers associated with cancer formation and inhibition. These results indicate that the reported potentiation of cancer therapy using drug-based medical chemotherapies with added checkpoint inhibitors in human patients are mechanistically similar with the functional food evaluated in the present study. These beneficial effects in mice challenge clinicians to investigate if the black rice bran food product can also protect against human cancer.

Protection of Allergic Asthma in Mice by Black Rice Bran Bioprocessed with Shiitake Mushroom Mycelia

We evaluated the potential of orally fed new food formulations to inhibit biomarkers reported to be involved in the causes of allergic asthma in mice. Asthma, a serious non-communicable disease, affects both adults and children and can be undertreated. New functional foods could provide therapeutic approaches. Here, the anti-asthma mechanism of a new functional food and three isolated fractions produced by bioprocessing black rice bran with shiitake mushroom mycelia was evaluated in mast cells, B cells, and orally fed mice and compared with non-bioprocessed black rice bran. In vitro, the treatments inhibited RBL-2H3 cell degranulation and immunoglobulin E (IgE) production. The in vitro anti-asthma effects were confirmed in orally fed mice following asthma induction by alumina and chicken egg ovalbumin (OVA). The suppression of asthma resulted from the inhibition of inflammation- and immune-related substances, including OVA-specific IgE, thymic stromal lymphopoietin, eotaxin, leukotriene C4, prostaglandin D2, and vascular cell adhesion molecule-1 in bronchoalveolar lavage fluid and serum. The treatment also reversed the thickening of the lung airway wall. The inflammation and asthma inhibition seems to be regulated by the balance of the T-helper cells’ Th1/Th2 immune response and the inhibition of multiple biomarkers associated with the cause of asthma. Future human clinical studies with adults and children should determine the potential therapeutic value of the anti-asthma effects of the new functional foods.

Study on Extraction Method of Selenium-enriched Rice

[Objectives] The aims were to optimize the extraction process of selenoproteins from selenium-enriched rice in Guangxi and provide references for the intensive processing and comprehensive utilization of selenium protein resources. [Methods]Selenium-enriched rice was used as materials to extract selenoproteins by phosphate buffer extraction method and to optimize the extraction process of selenoproteins by using the orthogonal experiment. Proteins and selenium content was measured by Coomassie Brilliant Blue G-250 reagent and AFS（ atomic fluorescence spectrometry） respectively. [Results] The most significant factor affecting extraction of rice Selenoproteins was extraction NaO H concentration,followed by the ratio of solid-liquid,temperature and then extraction time. The optimum extraction conditions of selenoproteins from rice were extraction temperature of 50 ℃,NaO H concentration of 0. 14 mol/L,extraction time of 5 h,and solid-liquid ratio of 1∶ 30. [Conclusions]The alkali extraction process optimized by orthogonal test could effectively improve the extraction rate of selenoproteins,and the optimized process parameters could be popularized and applied in practical production.

Chemical,Sensorial and Rheological Properties of a New Organic Rice Bran Beverage

Rice bran is a solid residue from rice polishing that is used in animal nutrition and rice oil production. Cultivation conditions with agro-toxics, lipids instability, and tendency for mycotoxin contamination restrict its application in human nutrition. Therefore, organic agriculture is an alternative to use the properties of rice bran. Rice bran beverage is a new cereal product from organic rice. This work presents the preliminary results of the chemical and rheological studies of a bath pasteurized rice bran beverage. Compared with integral defatted milk, soy extracts, and brown rice low-fat milk, the rice bran beverage studied in this work presents itself as an important source of minerals and unsaturated lipids. All essential amino acids were found in this product. Glutamic and aspartic acids were predominant. Bath pasteurization at boiling water temperature for 15 and 30 min was adequate for microbiological safety. Refrigeration storage for 20 days, evaluated by pH and acidity variations, was ideal for assessment of the beverage conservation time. The beverage viscosity was of the Newtonian standard behavior, and its viscosity during storage was not a good parameter to evaluate shelf life. Sensory preference tests showed positive perspectives for this new beverage.

A comprehensive review on anti-diabetic property of rice bran

Rice bran(RB) is one of the nutrient-rich agricultural byproducts. It is a composite of carbohydrates, lipids, proteins, fibers, minerals, and trace elements such as phosphorus, potassium, magnesium, calcium and manganese. The extraction and purification process influences the quality and quantity of rice bran oil, which is rich in tocopherols, tocotrienols, 毭-oryzanol, and unsaturated fatty acids. The bioactive components of RB have been reported for exhibiting antioxidant, anti-inflammatory, hypocholesterolemic, anti-cancer, anti-colitis, and antidiabetic properties. In vitro and in vivo studies, and clinical trials in human volunteers revealed the anti-hyperglycemic activity of RB derived compounds. An updated comprehensive review on the antidiabetic property of RB and its derivative is required to appraise the current knowledge in the particular field. Thus, the present paper covered the composition and bioactivities of RB, and influence of extraction methods on the biological property of rice bran oil and rice bran extract. And the current review also focused on the reported antihyperglycemia activity of rice bran derivatives, and its probable mechanism.

Quantitative analysis of γ-oryzanol content in cold pressed rice bran oil by TLC-image analysis method

Objective:To develop and validate an image analysis method for quantitative analysis ofγ-oryzanol in cold pressed rice bran oil.Methods:TLC-densitometric and TLC-image analysis methods were developed,validated,and used for quantitative analysis of γ-oryzanol in cold pressed rice bran oil.The results obtained by these two different quantification methods were compared by paired t-test.Results:Both assays provided good linearity,accuracy,reproducibility and selectivity for determination of γ-oryzanol.Conclusions:The TLC-densitomelric and TLC-image analysis methods providett a similar reproducibility,accuracy and selectivity for the quantitative determination of γ-oryzanol in cold pressed rice bran oil.A statistical comparison of the quantitative determinations of γ-oryzanol in samples did not show any statistically significant difference between TLC-densitometric and TLC-image analysis methods.As both methods were found to be equal,they therefore can be used for the determination of γ-oryzanol in cold pressed rice bran oil.

<i>In-Vitro</i>Fermentation by Human Fecal Bacteria and Bile Salts Binding Capacity of Physical Modified Defatted Rice Bran Dietary Fiber

Defatted rice bran dietary fiber (DRBDF) was modified by micronization, ultrasound, microwave and extrusion cooking. We investigated the impacts of these physical treatments on the fermentation ability and bile salts binding capacity of DRBDF. In-vitro fermentation by human fecal bacteria of modified fibers showed that the major fermentation products were propionic, acetate and butyrate acid. Fermentation of extruded fiber gave the highest amounts of propionic and acetic acid 135.76 and 25.45 mmol/L respectively, while, the fermented product with microwaved fiber had the highest butyric acid content (10.75 mmol/L). The amount of short-chain fatty acid increased from 12 h to 24 h and propionic acid was the predominant. On the other hand,in-vitrobile salts binding showed that extruded fiber had higher affinity with sodium deoxycholate and sodium chenodeoxycholate (66.14% and 30.25% respectively) while microwaved fiber exhibited the highest affinity with sodium taurocholate (14.38%). In the light of obtained results we can affirmed that these physical treatments significantly improved the fermentation products and bile salts binding capacity of DRBDF. Extrusion compared to the other physical treatment methods used in this study has greatly and positively influenced the fermentation and bile binding capacity of DRBDF.

Rice Bran Oil Extraction by Screw Press Method:Optimum Operating Settings,Oil Extraction Level and Press Cake Appearance

The appearance of rice bran ＇cake＇ or discharge from a screw press corresponds to the level of oil produced in the extraction process. The relationships between operating settings, oil extraction level and cake appearance were studied. Cake characteristics reliably indicate the expected oil recovery extraction level. These conclusions applyed to both Chainat 1 rice bran and parboiled rice bran. Variables were the speed of the screw press （set at five levels from 8.5 to 19.8 r/min） and corresponding clearance distances between the screw and barrel （set between 1.0 and 1.9 cm）. Results showed that the maximum levels of extraction were 4.17% for the rice bran and 8.20% for the parboiled rice bran. At the maximum extraction level, the apparatus continuously discharged cake that were hard, crispy, flaky, shiny and polished on one side but dull and coarse on the other.

Rice Bran Oil: Emerging Trends in Extraction, Health Benefit, and Its Industrial Application

Rice bran oil(RBO)is unique among edible vegetable oils because of its unique fatty acid composition,phenolic compound(γ-oryzanol,ferulic acid)and vitamin E(tocopherol and tocotrienol).It has become a great choice of cooking oil because of its very high burning point,neutral taste and delicate flavour.Non-conventional methods of RBO extraction are more efficient and environmentally friendly than conventional extraction methods.Advances in RBO extraction using innovative extraction strategies like super/sub-critical CO_(2),microwave-assisted,subcritical H_(2)O,enzyme-assisted aqueous and ultrasoundassisted aqueous extraction methods have proven to significantly improve the yields along with improved nutritional profile of RBO.The compositions and strategies for stabilization of RBO are well discussed.The constituents are present in the RBO contribute to antioxidative,anti-inflammatory,antimicrobial,antidiabetic and anti-cancerous properties to RBO.This has helped RBO to become an important substrate for the application in food(cooking oil,milk product and meat product)and non-food industries(polymer,lubricant,biofuel,structural lipid and cosmetic).This review provided comprehensive information on RBO extraction methods,oil stabilization,existing applications and health benefits.

Physico-Chemical and Sensory Evaluation of Wheat Bread Supplemented with Stabilized Undefatted Rice Bran

The effect of rice bran supplementation on some physicochemical and sensory properties of wheat bread was deter mined. Blends of wheat flour and rice bran (95:5, 90:10 and 85:15) were used to bake bread with 100% wheat flour as control. Thereafter, proximate, vitamin and mineral composition, as well as the physical and sensory properties of the dough and bread loaves were determined, using standard methods of analysis. The moisture content, crude protein, crude fat, crude fibre and ash of the composite bread loaves increased significantly (p < 0.05) from 21.07% to 23.67%, 12.04% to 13.10%, 1.57% to 3.77%, 1.76% to 2.91% and 1.46% to 2.41% respectively;while carbohydrate content decreased with increased level of supplementation from 62.10% to 54.14%. There were significant increases (p < 0.05) in vitamin B1 (Thiamin) from 0.15 mg/100g to 0.47 mg/100g and B2 (Niacin) from 3.31 mg/100g to 4.04 mg/100g but no significant increase (p > 0.05) in vitamin B3 (Riboflavin). Mineral content of the bread increased significantly (p < 0.05) with increased level of supplementation from 9.32 mg/100g to 20.52 mg/100g (Iron), 80.74 mg/100g to 188.20 mg/100g (Potassium), 81.31 mg/100g to 130.70 mg/100g (Calcium) and 13.65 mg/100g to 132.22 mg/100g (Magne sium). However, there was a significant decrease (p < 0.05) in sodium with increased level of supplementation from 305.25 mg/100g to 253.03 mg/100g. Bread loaf weight increased from 152.7 g to 162.7 g;while loaf volume decreased from 655.2 ml to 586.0 ml and specific loaf volume decreased from 4.29 ml/g to 3.60 ml/g. There were significant dif ferences (p < 0.05) in physical properties of dough and bread loaves between the composite bread and the control. Though 100% wheat bread had better acceptability scores (7.95) compared to composite bread (7.20 for 95:5 blend), all the composite bread samples had significantly (p < 0.05) higher values for nutritional parameters. There was therefore, a significant improvement in the nutritional composition of the wheat bread with rice bran supplementation.

Fermented rice bran prevents atopic dermatitis in DNCB-treated NC/Nga mice

The fermentation of natural plants has a favorable effect on the functional and biological activities of living systems. These include anti-oxidative, anti-inflammatory, and anti-platelet aggregation activities. This is attributed to the chemical conversion of the parent plants to functional constituents, which show more potent biological activity. In our study, rice bran along with oriental medicinal plants （Angelicae gigantis, Cnidium officinale, Artemisia princeps, and Camellia sinensis） was fermented by Lactobacillus rhamnosus and Pichia deserticola （FRBE）. We evaluated the effects of oral administration of FRBE on atopic dermatitis in 1-chloro-2,4-dinitrobenzene （DNCB）-treated NC/Nga mice. FRBE significantly ameliorated the macroscopic and microscopic appearance of skin lesions in DNCB-induced atopic dermatitis and reduced levels of serum immunoglobulin E and the differential white blood cell count. In addition, it reduced skin thickness compared to that of atopic dermatitis-affected skin. FRBE treatment also reduced mast cell incorporation in skin lesions of atopic dermatitis. The total cell number in dorsal skin tissue and the axillary lymph node increased following DNCB application, and this was normalized by FRBE treatment. Moreover, it decreased the levels ofCD8＋ helper T cells and Gr-1 ＋/CD1 lb＋ B cells in peripheral blood mononuclear cells and skin lesions in DNCB-induced atopic dermatitis. Using real-time polymerase chain reaction analysis, we demonstrated that FRBE significantly inhibited mRNA expression of cytokines （e.g., interleukin-5 and interleukin-13） and cyclooxygenase-2 in AD skin lesions. These results suggest that FRBE could be a valuable herbal remedy for the treatment of atopic dermatitis.

Enzymatic Synthesis of Fatty Acid Methyl Esters from Crude Rice Bran Oil with Immobilized Candida sp. 99-125

The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles.

Optimization of Extraction Technology for Rice Bran Oil

[ Objective ] This study aimed to optimize the extraction technology for rice bran oil. [ Method ] Using rice bran as raw material, effects of ultrasonicassisted extraction technology and different organic solvents, extraction durations, solid-liquid ratios and extraction temperatures on extraction results of rice bran oil were investigated. Based on the results of single-factor experiment, L9 （34 ） orthngonal experiment with three factors at three levels was conducted to optimize the extraction technological parameters, thus obtaining the optimal technological conditions for extracting rice bran oil. [ Result] Anhydrous ethanol led to the best extraction result; after ultrasonic treatment, the extraction rate of rice bran oil from raw material was not enhanced. The optimized technological parameters were ： extraction temperature of 80 ℃, extraction duration of 20 rain and solid-liquid ratio of 1：24 （ g： ml）. Under the optimized technological conditions, the extraction rate of rice bran oil reached 19.33%. [ Conclusion] This study laid solid foundation for further investigation and development of rice bran oil.

Sang-Yod rice bran hydrolysates alleviate hypertension, endothelial dysfunction, vascular remodeling, and oxidative stress in nitric oxide deficient hypertensive rats

Objective:To evaluate the potential therapeutic effect of Sang-Yod rice bran hydrolysates(SRH)and in combination with lisinopril against hypertension,endothelial dysfunction,vascular remodeling,and oxidative stress in rats with nitric oxide deficiency-induced hypertension.Methods:Hypertension was induced in male Sprague-Dawley rats by administration of a nitric oxide synthase inhibitor,Nω-nitro-L-arginine methyl ester(L-NAME)in drinking water for 6 weeks.Hypertensive rats were administered daily with SRH(500 mg/kg/day),lisinopril(1 mg/kg/day),or the combination of SRH and lisinopril by gastric lavage for the last 3 weeks of L-NAME treatment.Hemodynamic status,vascular reactivity to vasoactive agents,and vascular remodeling were assessed.Blood and aortic tissues were collected for measurements of oxidative stress markers,plasma angiotensin-converting enzyme(ACE)activity,plasma angiotensinⅡ,and protein expression.Results:L-NAME induced remarkable hypertension and severe oxidative stress,and altered contents of smooth muscle cells,elastin,and collagen of the aortic wall.SRH or lisinopril alone reduced blood pressure,restored endothelial function,decreased plasma ACEs and angiotensinⅡlevels,alleviated oxidant markers and glutathione redox status,and restored the vascular structure.The effects were associated with increased expression of endothelial nitric oxide synthase and decreased expression of gp91phox and AT1R expression.The combination of SRH and lisinopril was more effective than monotherapy.Conclusions:SRH alone or in combination with lisinopril exert an antihypertensive effect and improve endothelial function and vascular remodeling through reducing oxidative stress and suppressing elevated renin-angiotensin system.

Identification and Characterization of Lactic Acid Bacteria Isolated from Fermented Rice Bran Product

To analyze the microflora in fermented rice bran product, bacterial colonies were grown under various conditions. Although cultivation temperature did not affect the number of bacterial colonies formed on agar plates, twice as many colonies formed under aerobic as under anaerobic conditions. All colonies appearing on the plates showed acid production. Based on 16S rRNA sequence analysis, nearly all of the bacteria in the fermented product were highly similar (>99%) to Lactobacillus johnsonii. In addition, several Bacillus cereus and unidentified Lactobacillus strains that grew only under anaerobic conditions at 30℃?were seen. Random Amplified Polymorphic DNA (RAPD)-PCR analysis showed the amplified patterns of all isolates to differ substantially from the reference strain L. johnsonii. We conclude that L. johnsonii-related strains predominate in fermented rice bran product, and that these bacteria produce lactic acid to decrease the pH of the fermented product. Several novel Lactobacillus strains may also occur in this environment.

Anti-tumor activity of rice bran hydrolysates on migration, invasion and angiogenesis

Objective:To investigate anti-tumor effect of rice bran hydrolysates(RBH)on proliferation,migration,invasion,and angiogenesis of cholangiocarcinoma(CCA)cells,and elucidate the underlying mechanisms.Methods:RBH was prepared from Tubtim Chumprae rice(Oryza sativa L.)by hydrothermolysis followed by protease digestion.Phenolic content in RBH was analyzed by high-performance liquid chromatography.Human CCA cells,KKU-156,KKU-452,and KKU-100,were used to study the effects of RBH on proliferation,migration,invasion,and adhesion by wound healing,Transwell chamber,and fibronectin cell adhesion assays.Angiogenesis was evaluated using human umbilical vein endothelial cells.Proteins associated with cancer progression were analyzed by immunobloting assays.Results:RBH contained carbohydrates,proteins,lipids,and various phenolic compounds and flavonoids.RBH did not inhibit CCA proliferation,but strongly suppressed migration,invasion,adhesion of CCA cells,and the formation of tube-like capillary structures of human umbilical vein endothelial cells.Moreover,RBH downregulated phosphorylation of FAK,PI3K,and Akt,suppressed NF-κB nuclear translocation,decreased the expression of ICAM-1,vimentin and vascular endothelium growth factor(VEGF),and increased the expression of E-cadherin.Conclusions:RBH suppresses CCA cell migration and invasion and decreases expression of proteins involved in cancer metastasis.RBH is a potential food supplement for cancer prevention.

Effect of Effluent from Biodigestion of Pre-Treated Rice Bran and Animal Manure on the Dry Matter Yield and Nutrient Uptake of <i>Amaranthus viridis</i>

The effect of effluents from biodigestion of pre-treated rice bran in combination with two types of animal manure on dry matter yield of Amarathus viridis was investigated using two pre-treatment methods: Soaking in ordinary distilled water and boiled in distilled water at 100°C. The pre-treated rice bran and animal manure were mixed (w/w basis) to give carbon to nitrogen ratio of 35:1 and 37:1 prior to loading into the digester to make eight different treatment combinations as follow: 1) Cow dung with no rice bran (NRB + CD);2) Raw rice bran + cow dung (RRB + CD);3) Soaked rice bran in ordinary distilled water + cow dung (SRB + CD);4) Boiled rice bran + cow dung (BRB + CD);5) Poultry manure with no rice bran (NRB + PM);6) Raw rice bran + poultry manure (RRB + PM);7) Soaked rice bran + poultry manure (SRB + PM);8) Boiled rice bran + poultry manure (BRB + PM). Samples of different treatment combinations were collected before digestion, both the samples and resultant effluents were subjected to elemental analysis using AAS. The effluents from the biodigestion of these combinations were applied at two rates (80 and 150 kg N ha-1) to 3 kg air-dried and sieved soil samples (0 - 20) cm in the greenhouse, control (0 kg N ha-1) and reference pot with NPK fertilizer at the 80 kg N ha-1 were arranged in a completely randomized design replicated three times. Amaranthus plants were introduced into each treated pot, left for four weeks before harvest, dry matter yields were recorded. Results of chemical analysis of raw materials and effluents obtained after biodigestion revealed the presence of all plant nutrients in both the raw materials and resultant effluents though the former had higher values in some nutrients than the effluent, for examples treatment combination of CD, the values for organic carbon (42.85%), Ca (3.41%) and Mg (0.61%) were higher than in the resultant effluent for CD, a similar trend was observed with other treatment combinations. Drastic reduction in heavy metal concentration was observed after digestion, Pb content in the raw materials for poultry manure reduced by 94.7% in the resultant effluent from BRB: PM thus making the effluent a better soil amendment. Raw chicken manure was richer in the nutrients needed for optimal crop growth however, raw cow dung had the highest. The amendment of effluent from boiled rice bran with poultry manure at 150 kg N ha-1 significantly increased the dry matter yield of Amaranthus viridis over control pots, NPK pots and all other amendments thus making it a good alternative to NPK fertilizer.

Laboratory studies of rice bran as a carbon source to stimulate indigenous microorganisms in oil reservoirs

There is a great interest in developing cost-efficient nutrients to stimulate microorganisms in indigenous microbial enhanced oil recovery（IMEOR） processes.In the present study,the potential of rice bran as a carbon source for promoting IMEOR was investigated on a laboratory scale.The co-applications of rice bran,K2HPO4 and urea under optimized bio-stimulation conditions significantly increased the production of gases,acids and emulsifiers.The structure and diversity of microbial community greatly changed during the IMEOR process,in which Clostridium sp.,Acidobacteria sp.,Bacillus sp.,and Pseudomonas sp.were dominant.Pressurization,acidification and emulsification due to microbial activities and interactions markedly improved the IMEOR processes.This study indicated that rice bran is a potential carbon source for IMEOR.

Thai pigmented rice bran extracts inhibit production of superoxide, nitric oxide radicals and inducible nitric oxide synthase in cellular models

Objective:To study the inhibitory effect of rice bran extracts of Thai black Kam Muang and red Hawm Dawk Mali Deang on oxidative stress factors including superoxide(O2·-),nitric oxide(NO·),and inducible nitric oxide synthase(iNOS).Methods:Bran extracts(40%ethanol)of Kam Muang and Hawm Dawk Mali Deang were obtained and evaluated for in vitro 2-2′-azino-di-(3-ethylbenzthiazoline sulfonate)(ABTS)and NO·scavenging activity.Their inhibitory effects on cellular O2·-and NO·were measured in phorbol 12-myristate 13-acetate-stimulated neutrophil-like HL-60 cells and lipopolysaccharidestimulated RAW264.7 macrophages,respectively,and their viability was monitored using the MTT assay.The effect on iNOS expression was also assessed by the Western blotting assay.Total contents of phenolics,flavonoids,and subtypes were also determined.Results:Hawm Dawk Mali Deang exhibited about 3.5-fold greater cellular O2·-inhibitory activity than Kam Muang[EC50 values of(23.57±4.54)and(81.98±1.45)μg/mL,respectively]in phorbol 12-myristate 13-acetate-stimulated HL-60 cells.Hawm Dawk Mali Deang exhibited about 2-fold higher in vitro ABTS·+and NO·scavenging activity than Kam Muang,but it exerted cellular NO·inhibitory activity of only about 26%(undetermined EC50 value)in lipopolysaccharide-stimulated RAW264.7 cells.Conversely,Kam Muang exerted potent cellular NO·inhibitory activity[EC50 value:(281.13±59.18)μg/mL]and dose-dependently decreased iNOS levels.No cytotoxicity of both extracts was detected in both cell types.As for corresponding contents,Hawm Dawk Mali Deang contained higher contents of phenolics and flavonoids than Kam Muang.Moreover,Kam Muang and Hawm Dawk Mali Deang had a high content of total anthocyanins[(14.73±0.52)mg C3GE/g of extract]and total proanthocyanidins[(115.13±1.47)mg CE/g of extract],respectively.Conclusions:Based on these data,bran extracts of Thai black Kam Muang and red rice Hawm Dawk Mali Deang can help lower oxidative stress and inflammation attributed partly to O2·-and NO·.