INTRODUCTION:

Humans have enjoyed cereal foods since the last millennium. Cereal foods, including cereals, are a staple food for many people around the world. India is no exception to this rule. Among the main cereal foods, rice is used as the main food of many people in the country. It forms an important part of the diet of many people in this country. Most of the nutritional value of rice lies in its germ and bran, which were traditionally discarded during milling. When rice is milled, the main product is rice endosperm (70%), but by-products are rice husk (20%), rice bran (8%) and rice germ (2%). ^1-4

Rice bran is a rich source of protein, vitamins, fiber, antioxidants and has several health benefits. Due to its beneficial nutritional and biological effects, it can be incorporated into functional foods, but is still underutilized due to the lipase enzyme. The lipase enzyme in rice bran hydrolyzes the oil content into glycerol and free fatty acids. Due to this conversion, the quality of rice bran decreases. It creates an unpleasant smell and gives a bitter taste. Because of this rancidity problem, rice bran becomes unfit for human consumption and most rice bran used as animal feed or fuel is high in protein. ^{5, 6}

A considerable number of in vitro and in vivo studies have demonstrated the benefits of rice bran for certain health parameters through its antioxidant activity. Moderate consumption of antioxidant-rich foods is important for scavenging free radicals that cause oxidative stress, premature cell aging, and heart and muscle damage⁷. The crude rice bran oil obtained in the solvent extraction process undergoes either chemical refining⁸. Rice bran serves as a source of many individual bioactive compounds such as oils, fibers, proteins, and minerals, many of which have been extensively studied and shown to exhibit beneficial effects in vitro and in vivo. In addition, dietary supplements contained in rice bran extracts may play an important role in existing food crises in addition to related health claims. ⁹. India and Thailand have been the most successful countries in the production of rice bran oil. In India, a solvent extraction process from 40 million tons of rice bran yields about 6.5 million tons of rice bran oil ¹⁰

Fig No.: 01 Rice Bran

Currently, there are almost 22 types of rice, but the most consumed are Oryzasativa and Oryzaglaberrima, which are mainly grown in Asia and Africa. China is the primary producer and consumer of rice, followed by India and Indonesia (Fig. 1). China and India produced 148.5 million tons of milled rice and 116.4 million metric tons in the 2018/2019 marketing year. China is also a major consumer of rice (about 143.79 million tons per year), while India is a major exporter of milled rice worldwide (12.5 million tons in the 2018/2019 marketing year).^{11, 12}

RB is a by-product of milling brown rice into white rice. It is a multi-step process used by sophisticated grinding systems on an industrial scale. Multi-stage milling reduces mechanical stress and heat build-up in the grain, thereby minimizing grain breakage and increasing the yield of headed rice. The yield of headed rice, unbroken white rice, is the basis for grading rice quality and determining market value. The bran layer is removed by bleaching and polishing. Whitening machines remove the layers of bran and rice germ, and polishing machines remove the remaining bran by polishing the outside of the milled kernel, improving the appearance of milled or white rice. Composite RB consists of the coarse bran fraction from the bleaching steps and the fine bran fraction or polish (the part of the bran fractions containing the most endosperm) from the polishing step. Composite RB may also contain rice sprouts and small fractions of rice husks.¹³

Nutritional Richness of Rice Bran:

Nutritional Composition of RB:

Rice bran is the brown outer layer of the rice kernel, which mainly consists of the pericarp, aleurone, seed coat and germ. It contains 50% carbohydrates (mainly starch), 20% fat, 15% protein and 15% fiber (DF), mainly insoluble fiber. ^{14, 15} The nutritional composition of raw RB per 100 g was shown in Table 1, Table 2 and Table 3. However, the nutrient composition of RB depends on the rice variety and the efficiency of the milling system ¹⁶.

Table No.:01¹⁶

Sr. No.	Nutrient	Amount
1	Energy (kcal)	316
2	Protein (g)	13.35
3	Total fat (g)	20.85
4	Saturated fatty acids (g)	4.17
5	Monounsaturated fatty acids (g)	7.55
6	Polyunsaturated fatty acids (g)	7.46
7	Carbohydrate (g)	49.69
8	Fiber, total dietary (g)	21.00

Table No.: 02¹⁶

Sr. No.	Minerals	Amount
1	Calcium (mg)	57.00
2	Iron (mg)	18.54
3	Magnesium (mg)	781.00
4	Phosphorus (mg)	1677.00
5	Potassium (mg)	1485.00
6	Zinc (mg)	6.04
7	Manganese (mg)	14.21
8	Selenium (µg)	15.60

Table No.: 03¹⁶

Sr. No.	Vitamins	Amount
1	Thiamine (mg)	2.75
2	Riboflavin (mg)	0.28
3	Niacin (mg)	34.00
4	Pantothenic acid (mg)	7.39
5	Vitamin B6 (mg)	4.07
6	Folate (µg)	63.00
7	Choline (mg)	32.20
8	Vitamin E (alpha-tocopherol) (mg)	4.92
9	Vitamin K (phylloquinone) (µg)	1.90

Rice bran dietary fiber:

RB contains approximately 12% DF, of which 90% is insoluble DF including cellulose, hemicellulose and arabinoxylans.^17,18However, the amount and composition of nutrients in RB varies depending on the rice cultivar, environmental conditions, milling degree, and analytical method.¹⁹

Cellulose:

RB contains approximately 34% cellulose. Cellulose is a long-chain homopolymer with a high degree of polymerization, ranging from a few 100 to more than 10,000 monomers, and a large molecular weight. ^20,21The mechanism underlying the immunomodulatory activity of arabinoxylans is still unclear, but it has been hypothesized that it is mediated by competition with lipopolysaccharides (LPS) from Gram-negative bacteria for the macrophage TLR4 receptor.³² The immunomodulatory activity of arabinoxylans depends on several factors, such as the degree of branching, molecular weight and composition of sugar. One type of RB arabinoxylan, known as MGN-3, has been shown to be more effective at activating macrophages than wheat bran arabinoxylan due to higher levels of glucose and galactose side chains. ^{22, 23}

Gamma-oryzanol:

Gamma-oryzanol is present in the form of sterylferulate, which is a mixture of ferulic acid esters with sterol and triterpene alcohols.^24,25Gamma-oryzanol is present in approximately 20% of the unsaponifiable fraction in RB oil ²⁶Gamma-oryzanol is considered one of the most potent natural antioxidants. Functional activities of gamma-oryzanol that have been reported include antioxidant activity, antidiabetic activity, hypolipidemic effect, and anticancer properties. ^27-31

Antioxidant Properties of Rice Bran:

Research on the antioxidant activity of rice bran has been widely published. Rice bran extract using 80% methanol has the highest antioxidant activity compared to using other solvents such as 100% methanol, 80% acetone, and 100% acetone. Antioxidant activity testing methods were performed in different systems, namely the linoleic acid system, the β-carotene linoleic acid system, and using sunflower oil as an oxidizing substrate.³²In general, many methods of antioxidant activity analysis use the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical because it is stable. The principle behind this method is that the colour of DPPH changes from purple to yellow when it receives a hydrogen atom donor from a bioactive compound. In addition, another widely used method for the analysis of antioxidant activity is the ABTS method (2, 2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid). The principle of this method is to reduce the intensity of the blue colour of ABTS radicals in the presence of bioactive antioxidant compounds.³³

Determination of DPPH was determined using a hydrogen donation mechanism. Scavenging effects of all samples were significantly different for both varieties and extraction methods（p ≤ 0.05). The DPPH IC₅₀ value represents the concentration that inhibits 50% of the process. HN rice RBO samples extracted by three methods used the lowest concentration to inhibit 50% compared to KDML 105 and RJM rice RBO samples. In addition, the RBO sample from HN rice extracted with SC-CO₂ gave the lowest IC₅₀ value of 0.93 mg/g oil. For the FRAP assay, the antioxidant activity was 38.18–89.76 μM TE/g oil, and the RBO sample produced from HN rice showed the highest value, followed by RJM and KDML 105 rice. The trend of antioxidant activity observed by the FRAP assay was similar to that observed by DPPH IC50. Regarding ORAC, the RBO sample from HN rice extracted with SE gave the best results, 690.10 μM TE/g oil. It can be concluded that RBO samples from coloured rice showed better antioxidant activity than white rice samples. This result is consistent with previously published Fujita et al and Sompong et. al.^{34, 35}

Cholesterol Management:

RBOs have a hypocholesterolaemia effect resulting from the selective reduction of the low-density lipoprotein (LDL) fraction of cholesterol (C). This effect was much larger than predicted values (Table 4). This discrepancy can be attributed to the presence of a high concentration of unsaponifiables including phytosterols, oryzanols and tocotrienols.^36-39Phytosterols have been considered cholesterol-lowering substances since the 1950s. Most studies to date have focused on the effects of beta-sitosterol and sitostanol in lowering LDL and circulating cholesterol. These results suggest that these agents may be hypolipidemic agents in mild hypercholesterolemia by altering lipid metabolism, for example, by reducing the activity of hepatic acetyl Co-A carboxylase and malic acid.^40,
42

Gamma-oryzanol has also been found to have similar hypocholesterolemic effects. Feeding low and high gamma-oryzanol RBO for four weeks reduced plasma total cholesterol (6.3%), LDL-C (10.5%) and LDL-C/HDL-C ratio (18.9%).⁴³

Table No, 04 Cholesterol lowering activity of RBO in comparison to other edible oils⁴⁴

Edible Oils	Linolenic Acid %	Cholesterol Level
Safflower	77.1	-16
Sunflower	61.4	-12
Cottonseed	58.0	0
Soybean	50.2	+3
Sesame	45.9	+2
Corn	43.0	-15
Rice Bran	35.0	-17

Rice Bran Effect on Digestive Health:

Daily supplementation of RB (30/g) in colorectal cancer patients for 4 weeks helped to meet the recommended amount of DF without causing gastrointestinal distress and changing stool consistency.^[45]Another study found that supplementation of RB-derived arabinoxylan for 4 weeks in patients with inflammatory bowel syndrome (IBS) improved reflux, diarrhoea, and constipation. The improvement in gastrointestinal function in IBS patients may have been mediated by an immunomodulatory effect, as levels of inflammatory biomarkers were also reduced. RB fermentation shifts the intestinal microflora and stimulates the mucosal balance in the intestinal tract.⁴⁶

Extraction Of Rice Bran⁵²:

· Cold-press extraction（CPE): Rice bran was continuously fed into the hopper of a 2HP screw press extractor. Crude oil was forced through slots along the length of the barrel. Pressed rice bran was simultaneously discharged through a throttle valve at the end of the barrel.

· Solvent extraction (SE): The extraction process was carried out in the laboratory. The ratio of rice bran: hexane used was 1:3 (w/v) and the extraction was carried out for 3 hours with regular stirring. The bran was separated from the extract by filtration through No. 4 filter paper under vacuum.

· Supercritical carbon dioxide extraction（SC-CO₂）: Oil was extracted from rice bran using a SC-CO₂ extractor under the following conditions; temperature 60℃, pressure 30 MPa and CO₂ flow 35 l/h. The rice bran sample was placed in an extraction vessel and filled with glass beads at the bottom and top of the cell. The cell was placed in a heating chamber to maintain the operating temperature.

Refining of the rice bran oils:

Refining processes included dewaxing (cooling the oil and removing wax by centrifugation at 6000 rpm for 15 minutes), degumming (washing the oil with hot water (80 °C) with 85% H₃PO₄ solution), neutralization (washing the oil with hot water (80 °C) and centrifugation at 6000 rpm for 15 min until pH 7 was reached, bleaching (7% bleaching clay and 0.7% activated carbon at 120 °C under vacuum for 30 min) and deodorization (steaming the oil at 220°C under vacuum for 60 minutes.⁵³

Determination of γ-oryzanol:

γ-oryzanol was determined by the RP-HPLC method. Refined oils (50 mg) were dissolved in methanol (3 mL) and vigorously stirred for 3 min at room temperature before filtration through a PTFE syringe filter (0.2 μm). The RP-HPLC consisted of an Agilent 1100 series (USA), a column oven equipped with a Hypersil ODS (4.0 × 250 mm, 5 μm, Agilent Technologies, USA) and a variable wavelength UV-V IS detector (model G1379A) on 330 nm. A mixture of methanol: acetonitrile: dichloromethane: acetic acid in the ratio 50:44:3:3 v/v/v/v was used as the mobile phase with a flow rate of 1.0 mL/min. The content of total γ-oryzanol was calculated from the peak area of γ-oryzanol compared to standard γ-oryzanol. ^54-56

Determination of α-tocopherol:

A sample of oil (0.5 g) was diluted with n-heptane (10 mL) in a volumetric flask and filtered through syringe filters (0.45 μm). α-Tocopherol was separated on an RP-HPLC (Agilent 1100 series equipped with a Mightysil RP-18 GP column (4.6 x 250 mm, 3 μm, Kanto Chemical Co., Inc., Tokyo, Japan) and a fluorescent FLD G1321A detector working with excitation and emission wavelengths of 290 and 330 nm. The mobile phase was n-heptane and 2% isopropyl alcohol at a flow rate of 1.0 mL/min. The peak areas of standard α-tocopherol were used to calculate α-tocopherol content. The α-tocopherol of RBO refined was measured by the method of Speek et.al. and AOAC.^{57, 58}

Future perspective:

· State and central government, non-governmental organizations and other private entities organizations need to identify and explore more uses of RBO.

· Awareness among people by doctors, dieticians, cardiologists, nutritionists and health advisors etc. should focus on healthbenefits of rice bran oil.

· Associations and organizations such as the Asian Society of Rice Bran Oil, International Solvent Extractors Association of India and The International Association of Rice Bran Oil should update frequently benefits and statistics about RBO.

CONCLUSION:

In conclusion, this review has unveiled the nutritional prowess of rice bran as a dietary gem. From its rich composition of vitamins, minerals, and dietary fiber to its potent antioxidant properties, rice bran offers a host of health benefits. Its cholesterol-lowering effects make it a promising candidate for cardiovascular health, while its positive impact on digestive well-being is evident. The extraction process and determinations of gamma oryzanol and alpha tocopherol provide a roadmap for harnessing rice bran's nutritional potential. Looking ahead, the future perspectives of rice bran research hint at exciting developments and applications that can further elevate its status as a nutritional powerhouse. As we continue to explore and unlock the full spectrum of health benefits that rice bran has to offer, it is clear that this unassuming ingredient has the potential to revolutionize the field of nutrition and well-being.

REFERENCE:

1. Van Hoed V, Depaemelaere G, Villa Ayala J, Santiwattana P, Verhe R, De, et al., Influence of chemical refining on the major and minor components of rice bran oil. JAOCS. 2006; 83:315-321.

2. Anonymous. Sea Handbook-2009. 9th ed. The solvent extractor’s association of India: India, 885-891.

3. Wells J H, Utilization of rice bran and oil in human diets, Louisiana Agriculture. 1993; 36: 4-8.

4. De Deckere E A M, Korver O, Minor constituents of rice brain oil as functional foods, Nutr Rev. 1996; 54: S120-S126

5. Tao J, Rao T and Liuzzo Z, Microwave heating for rice bran stabilization, Journal of Microwave Power and Electromagnetic Energy. 1993; 28: 156-164.

6. Lakkakula N L, Lima M and Walker T, Rice bran stabilization and rice bran oil extraction using ohmic heating, Journal Bioresource Technology. 2004; 92: 157-161.

7. Brancaccio M, Mennitti C, Cesaro A, et al. Dietary thiols: a potential supporting strategy against oxidative stress in heart failure and muscular damage during sports activity. Int J Environ Res Public Health. 2020; 17: 9424.

8. Gopalakrishna A G, Value-added Products from Rice Bran Oil Industry, SAARC Oils Fats Today (August 2003) 20-23.

9. M. K. Sharif, M. S. Butt, F. M. Anjum and S. H. Khan, Rice bran: a novel functional ingredient, Crit. Rev. Food Sci. Nutr. 2014; 54: 807–816

10. Anonymous. Sea Handbook. 9th ed. The solvent extractor’s association of India: India. 2009: 885-891.

11. Shahbandeh M (2020) Top countries based on production of milled rice 2018/2019. Statista https://www.statista.com/ statistics/255945/top-countries-of-destination-for-us-rice-exports 2011/ accessed 11 Apr 2020

12. Shahbandeh M (2020) Top countries based on production of milled rice exporting countries world wide in 2018/2019. Statista https://wwwstatistacom/statistics/ 255947/top-rice-exporting-countries-worldwide-2011/ Accessed 11 Apr 2020

13. Rice Knowledge Bank, IRRIb. Available online: http://www.knowledgebank.irri.org/step-by-step-production/postharvest/ milling/milling-systems?tmpl=componentandprint=1 (accessed on 17 February 2023).

14. Gul K, Yousuf B, Singh AK, Singh P, Wani AA. Rice bran: nutritional values and its emerging potential for development of functional Food—a review. Bioact Carbohydr Diet Fibre. 2015; 6: 24-30

15. Nagendra Prasad Mn NP, Kr S, Khatokar M S. Health benefits of rice bran - a review. Nutr Food Sci. 2011; 1: 1-7. doi:10.4172/2155-9600.1000108

16. Sharif MK, Butt MS, Anjum FM, Khan SH. Rice bran: a novel functional ingredient. Crit Rev Food Sci Nutr. 2014; 54: 807-816.

17. Daou C, Zhang H. Functional and physiological properties of total, soluble, and insoluble dietary fibres derived from defatted rice bran. J Food Sci Technol. 2014; 51: 3878-3885.

18. Oliveira Mdos S, Feddern V, Kupski L, Cipolatti EP, Badiale-Furlong E, de Souza-Soares LA. Changes in lipid, fatty acids and phospholipids composition of whole rice bran after solid-state fungal fermentation. Bioresour Technol. 2011; 102: 8335-8338.

19. Kalpanadevi C, Singh V, Subramanian R. Influence of milling on the nutritional composition of bran from different rice varieties. J Food Sci Technol. 2018; 55: 2259-2269.

20. Sun S, Sun S, Cao X, Sun R. The role of pretreatment in improving the enzymatic hydrolysis of lignocellulosic materials. Bioresour Technol. 2016; 199: 49-58.

21. Brigham C. Biopolymers. In: Török B, Dransfield T, eds. Green Chemistry. Elsevier; 2018; 753-770.

22. Fadel A, Plunkett A, Li W, et al. Arabinoxylans from rice bran and wheat immunomodulatory potentials: a review article. Nutr Food Sci. 2018; 48: 97-110.

23. Zhang S, Li W, Smith CJ, Musa H. Cereal-derived arabinoxylans as biological response modifiers: extraction, molecular features, and immune-stimulating properties. Crit Rev Food SciNutr. 2015; 55: 1035-1052.

24. Minatel IO, Francisqueti FV, Corrêa CR, Lima GP. Antioxidant activity of γoryzanol: a complex network of interactions. Int J Mol Sci. 2016; 17: 11. doi:10.3390/ijms17081107

25. Butsat S, Siriamornpun S. Antioxidant capacities and phenolic compounds of the husk, bran and endosperm of Thai rice. Food Chem. 2010; 119: 606-613.

26. Yu S, Nehus ZT, Badger TM, Fang N. Quantification of vitamin E and gammaoryzanol components in rice germ and bran.. J Agric Food Chem. 2007; 55: 7308-7313.

27. Rungratanawanich W, Abate G, Serafini MM, et al. Characterization of the antioxidant effects of γ-oryzanol: involvement of the Nrf2 pathway. Oxid Med Cell Longev. 2018; 2018: 2987249.

28. Masuzaki H, Kozuka C, Okamoto S, Yonamine M, Tanaka H, Shimabukuro M. Brown rice-specific γ-oryzanol as a promising prophylactic avenue to protect against diabetes mellitus and obesity in humans. J Diabetes Invest. 2019; 10: 18-25.

29. Wang O, Liu J, Cheng Q , et al. Effects of ferulic acid and γ-oryzanol on high-fat and high-fructose diet-induced metabolic syndrome in rats. PLoS One. 2015; 10:e0118135.

30. Kobayashi E, Ito J, Shimizu N, et al. Evaluation of γ-oryzanol accumulation and lipid metabolism in the body of mice following long-term administration of γoryzanol.. Nutrients. 2019; 11: 104. doi:10.3390/nu1101010

31. Huh JY, Son DJ, Lee Y, et al. 8-hydroxy-2-deoxyguanosine prevents plaque formation and inhibits vascular smooth muscle cell activation through Rac1 inactivation. Free RadicBiol Med. 2012;53:109-121

32. ShahidChatha, S.A.; Anwar, F.; Manzoor, M.; RehmanBajwa, J. Evaluation of the Antioxidant Activity of Rice Bran Extracts Using Different Antioxidant Assays. GrasasAceites 2006; 57: 328–335.

33. Sunitha, D. A review on antioxidant methods. Asian J. Pharm. Clin. Res. 2016; 9: 14–32.

34. Fujita, A.; Fujitake, H.; Kawakami, K.; Nomura, M. Anti-oxidant activity of colored rice bran obtained at different milling yields J. Oleo Sci. 2011; 59: 563-568.

35. Sompong, R.; Siebenhandl-Ehn, S.; Linsberger-Martin, G.; Berghofer, G.E. Physicochemical and antioxidative properties of red and black rice varieties from Thailand, China and Sri Lanka. Food Chem. 2011; 124: 132-140.

36. Hu W, Wells JH, Tai-Sun S, Godber JS. Comparison of Isopropanol and Hexane for Extraction of Vitamin E and Oryzanols from Stabilized Rice Bran. JAOCS. 1996; 73: 1653-1656. 11.

37. Lichtenstein AH, Ausman LM, Carrasco W, Gualtieri LJ, Jenner JL, et al. Rice bran oil consumption and plasma lipid levels in moderately hypercholesterolemic humans. Arterioscler Thromb. 1994; 14: 549-556.

38. Hegsted M, Windhauser MM. Reducing human heart disease risk with rice bran. Louisiana Agriculture. 1993; 36: 22-23.

39. Orthoefer FT. Rice Bran Oil: Healthy Lipid Source. Food Tech. 1996; 50: 62-64.

40. Ling WH, Jones PJH. Dietary Phytosterols: A review of metabolism, benefits and side effects. Life Sciences 1995; 57: 195-206

41. Kahlon TS, Saunders RM, Sayre RN, Chow FI, Chiu MM, et al. Cholesterol-lowering effects of rice bran and rice bran oil fractions in hypercholesterolemic hamsters. Cereal Chem. 1992; 69: 485-489.

42. Yoshino G, Kazumi T, Amano M, Tateiwa M, Yamasaki T, et al. Effects of γ-oryzanol on hyperlipidemic subjects. Curr Therapeutic Res. 1989; 45: 543-552.

43. Berger A, Rein D, Schäfer A, Monnard I, Gremaud G, et al. Similar cholesterol-lowering properties of rice bran oil, with varied γ-oryzanol, in mildly hypercholesterolemic men. Eur J Nutr. 2005; 44: 163-173.

44. Anonymous. Sea Handbook. 9th ed. The solvent extractor’s association of India: India, 2009: 885-891.

45. Borresen EC, Brown DG, Harbison G, et al. A randomized controlled trial to increase navy bean or rice bran consumption in colorectal cancer survivors. Nutr Cancer. 2016; 68: 1269-1280.

46. Kamiya T, Shikano M, Tanaka M, et al. Therapeutic effects of biobran, modified arabinoxylan rice bran, in improving symptoms of diarrhea predominant or mixed type irritable bowel syndrome: a pilot, randomized controlled study. Evid Based Complement Alternat Med. 2014; 2014: 828137.

47. Justo ML, Rodriguez-Rodriguez R, Claro CM, Alvarez de, Sotomayor M, Parrado J, Herrera MD. Water-soluble rice bran enzymatic extract attenuates dyslipidemia, hypertension and insulin resistance in obese zucker rats. Eur J Nutr. 2013; 52: 789-797.

48. Devarajan S, Chatterjee B, Urata H, et al. A blend of sesame and rice bran oils lowers hyperglycemia and improves the lipids. Am J Med. 2016;129:731-739.

49. Piotrowicz IBB, Garcés-Rimón M, Moreno-Fernández S, Aleixandre A, SalasMellado M, Miguel-Castro M. Antioxidant, angiotensin-converting enzyme inhibitory properties and blood-pressure-lowering effect of rice bran protein hydrolysates. Foods. 2020; 9: 812.

50. Jan-On G, Sangartit W, Pakdeechote P, et al. Virgin rice bran oil alleviates hypertension through the upregulation of eNOS and reduction of oxidative stress and inflammation in L-NAME-induced hypertensive rats. Nutrition. 2020; 69: 110575.

51. Senaphan K, Sangartit W, Pakdeechote P, et al. Rice bran protein hydrolysates reduce arterial stiffening, vascular remodeling and oxidative stress in rats fed a high-carbohydrate and high-fat diet. Eur J Nutr. 2018; 57: 219-230

52. Sukanya Mingyai, Aikkarach Kettawan, KhongsakSrikaeo and RiantongSinganusong Physicochemical and Antioxidant Properties of Rice Bran Oils Produced from Colored Rice Using Different Extraction Methods, Journal of Oleo Science

53. Pestana, V.R.; Zambiazi, R.C.; Mendonça, C.R.B.; Bruscatto, M.H.; Lerma-Garcia, M. J.; Ramis-Ramos, G. Quality changes andtocopherols and γ-oryzanol concentrations in RBO during the refining process. J. Am. Oil Chem. Soc. 2008; 85: 113-119.

54. Iqbal, S.; Bhanger, M.I.; Anwar, F. Antioxidant properties and components of some commercially available varieties of rice bran in Pakistan. Food Chem. 2005; 93: 265- 272.

55. McBride, H.D.; Evans, D.G. Rapid voltammetricmethod for the estimation of tocopherols and antioxidants in oils and fats. Anal. Chem. 1973; 45: 446-452.

56. Chen, M.H.; Bergman, C.J. A rapid procedure for analysing rice bran tocopherol, tocotrienol and γ-oryzanol contents. J. Food Comp. Anal. 2005; 18: 139-151

57. Speek, A.J.; Schrijver, J.; Scherurs, W.H.P. Vitamin E composition of some seed oils as determined by highperformance liquid chromatography with fluorometric detection. J. Food Sci. 1985; 50: 121-124.

58. AOAC. Official methods of analysis. 18th ed. Association of Official Analytical Chemists, Washington, D. 2005.

Received on 08.02.2024 Modified on 05.03.2024

Asian J. Pharm. Res. 2024; 14(2):169-174.

DOI: 10.52711/2231-5691.2024.00028

Source	Amount and duration	Bioactivity	Reference
RB enzymatic extract	1% and 5% in obese Zucker rats, 20weeks	Weight reduction, antidiabetic, hypolipidemic activity, antihypertensive	Justo et al.⁴⁷
Blended oil (sesame and RB oil)	40mL/day in type 2 diabetes patients, 8weeks	Antidiabetic, hypolipidemic activity	Devarajan et al ⁴⁸
RB protein hydrolysates	80mg/kg in male spontaneously hypertensive rats	Antioxidant, antihypertensive	Piotrowicz et al⁴⁹
Virgin RB oil	2mL/kg in hypertensive rats, 3weeks	Antioxidant, anti-inflammation, antihypertensive	Jan-On et al ⁵⁰
RB protein hydrolysates	250 and 500mg/kg/day in male Sprague– Dawley rats, 6weeks	Antidiabetic, hypolipidemic activity, antihypertensive, anti-inflammation, antioxidant, restoration of normal endothelial function	Senaphan et al⁵¹