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The amount and distribution of rice endosperm lipids can influence starch digestibility and nutritional properties of white rice. However, this aspect has been poorly investigated thus far. We investigated the digestion properties of five rice varieties and common rice having different lipid contents (8.1-24.2 g kg-1) showing that the lipid content is positively correlated with the resistant starch content and negatively correlated with digestion extent (C∞) and estimated glycemic index (eGI). After non-starch lipid (NSL) removal from selected high-lipid mutants (ALK3 and RS4), C∞ was significantly enhanced compared to native samples when digested by α-amylase, while this phenomenon was not observed in low-lipid rice (GZ93). When pancreatin was used, starch digestion was only delayed; triglycerides were gradually hydrolyzed by pancreatic lipase and the lipids-starch complex became no longer resistant to hydrolysis by α-amylase. These results indicated that rice endosperm lipids inhibited starch digestion, by transforming part of the starch into a slowly digestible starch fraction. High-lipid mutants also had a higher total amount of, and more bioaccessible, γ-oryzanol than low-lipid varieties. This study indicates that high-lipid white rice has great potential in designing functional rice-based foods, combining a relatively lower eGI and a high γ-oryzanol content.

A new process was developed to extract tocols and γ-oryzanol from rice bran using ultrasound with soybean oil as a natural solvent. Results were compared to the conventional solvent method. The extraction process was optimized using response surface methodology (RSM) with three independent process variables as amplitude level (A) (20-60%), extraction temperature (B) (25-65°C) and time (C) (20-60 mins). Statistical analysis indicated that models developed for all responses were significant. Linear terms of all process variables had significant effects on α-tocopherol, γ-tocopherol, and γoryzanol, while quadratic effects of amplitude level (A2), temperature (B2) and time (C2) on all responses were highly significant. Optimal process conditions for maximum yield of tocopherols and γ-oryzanol were 40% amplitude level, 65°C solution temperature and 40 mins. Yields of α-tocopherol and γ-oryzanol in oil extracted under the optimal conditions or ultrasound-assisted soybean oil extraction (O-UASO) were comparable to oil yield produced by conventional solvent extraction (O-CSE). Interestingly, O-UASO showed higher total antioxidant activities compared with O-CSE. Extraction using ultrasound with soybean oil was proposed as an effective alternative green process to improve oil functionality without the need for separating environmentally hazardous organic solvents.

Thirty-nine Thai rice cultivars, including 17 non-colored rice cultivars and 22 colored rice cultivars (black rice cultivars and red rice cultivars), were investigated for γ-oryzanol content. The γ-oryzanol content of non-colored rice cultivars and colored rice cultivars was found to be 226.40 ± 17.50 μg/g to 411.80 ± 19.80 μg/g and 295.80 ± 15.40 μg/g to 459.80 ± 6.60 μg/g, respectively. Black rice cultivars seem to have higher γ-oryzanol content than do red rice and non-colored rice cultivars. The highest γ-oryzanol levels were identified in Khao Jao Dam Sa-Nit, a black rice cultivar, which contained 1.55 and 2.03 times more γ-oryzanol than Khao Man Bpoo, a red rice cultivar with lowest γ-oryzanol levels, and Khao Gor Kor 57, a non-colored rice cultivar with lowest γ-oryzanol levels, respectively. For further investigation, the effects of gamma irradiation on the γ-oryzanol content of four germinated Thai market rice cultivars, Khao Pathum Thani 1, Khao Gor Kor 31, Khao Gor Kor 41, and Khao Gor Kor 57, was investigated. The highest increase in γ-oryzanol content among the gamma irradiated rice cultivars was identified in Khao Pathum Thani 1 and Khao Gor Kor 31, which had γ-oryzanol levels approximately 1.27 times higher than that of the control rice (non-gamma irradiated rice). Our report contains basic knowledge about creating new rice lines that are rich in highly beneficial nutrients.

Rice (Oryza sativa L.) bran accumulates many compounds that are associated with the promotion and maintenance of human health, such as γ-oryzanol (gOZ) and γ-aminobutyric acid (GABA). These beneficial compounds in the bran fraction are mostly removed in polished rice. The present study sought rice cultivars with high concentrations of gOZ, and also of GABA, in polished rice, and examined the distribution of gOZ content in the outer layers of brown rice. The effects of germination treatment were also examined as a means to enrich gOZ and GABA in polished rice. GABA concentration showed no significant variation among 19 cultivars in polished rice, whereas a wide variation was detected in brown rice, for which cultivar Kinuhikari had the highest amount. Germination treatment for 5 h significantly enhanced GABA concentration. gOZ concentrations also showed a wide variation among cultivars in both brown rice and polished rice, with no clear correlation. Hattan, a sake-brewing cultivar, exhibited the highest gOZ concentration in polished rice. This cultivar involved higher gOZ in the outermost layer of polished rice, whereas it had a lower content in the bran fraction. This permeation of gOZ into polished rice might be related to the endosperm properties characteristic to sake-brewing cultivars. In contrast to GABA, gOZ concentration did not increase with germination treatment in brown rice or polished rice. Because the gOZ concentration in polished rice was insufficient even in the Hattan cultivar, breeding and/or other processing techniques are needed to obtain gOZ-enriched polished rice. Percentages of γ-oryzanol (gOZ) content in different layers and the core of brown rice. (a) Comparison among layers and the core in each of six rice cultivars, and (b) comparison among six cultivars in each of the layers and the core. Means with the same letter did not differ significantly at the 0.01 probability level, within each cultivar (a) and within each layer or the core (b). See text for layers and core.

A comparative study on physicochemical hydrolysis methods, including acid-catalyzed, base-catalyzed, and subcritical water hydrolysis, for glycerides removal prior to subsequent γ-oryzanol purification from rice bran acid oil (RBAO), is presented. The effects of hydrolysis conditions on the residual levels of glycerides and γ-oryzanol in RBAO were first investigated for each method. It can be concluded that the acid-catalyzed hydrolysis was not a suitable hydrolysis method for this application as it provided a low glycerides conversion level of ca. 30% using 2 N H2SO4 at 80–100 °C, despite the long reaction time (> 60 min). For the base-catalyzed hydrolysis, 100% glycerides removal was achieved at the most suitable condition, which was suggested to be at 2.5 N NaOH, 90 °C and 5–10 min. At this condition, a relatively high residual level of γ-oryzanol of ca. 57–66% was obtained. For the subcritical water hydrolysis, the results suggested that γ-oryzanol was hydrolyzed more rapidly than glycerides, and the most suitable condition for subcritical water hydrolysis was at 220 °C for 10 min. At this condition, high glycerides removal of > 95% was achieved while the remaining amount of γ-oryzanol was still acceptable (50%).

Germination can alter the physicochemical, nutritional, and nutraceutical value of brown rice. This study aimed to evaluate some characteristic changes from five Indonesian brown rice varieties during germination. The germination was carried out through a complete soaking method for up to 120 h, and the samples were taken and analyzed every 24 h. The results showed that germination increased GABA (γ-aminobutyric acid) content in brown rice. The highest level of GABA, up to 126.55 mg/100 g, obtained in rice var. Inpari 43, after 120 h. Germination also affected the changes in phenolic content, antioxidant capacity, and γ-oryzanol, while fatty acid compositions showed no changes. The pasting properties changed significantly after germination, especially in peak viscosity, final viscosity, breakdown, and setback. In conclusion, the changes in brown rice characteristics during germination, especially for increased GABA content and shifting of pasting properties, are valuable information for developing functional rice-based food products.

For the past several decades, only a few studies were conducted on the change in immature rice liposomes during seed development. To evaluate and compare the lipid material of different degrees of developing rice grains, this paper focused on fresh rice seeds from only one most popular species of Dasan divided into five growth periods. The lipid components of fresh rice, especially γ-oryzanol and fatty acids equipped with extremely beneficial phytonutrients, were investigated. The results illustrated that the level of extracted liposome increased gradually along with the development of rice and in the third stage of development, the level of liposome achieved maximum. And then, instead of increasing, it was decreased at later stages of development. Moreover, the antioxidant activity of fresh edible rice (FER) was also evaluated by DPPH and ABTS assay. It was shown that FER has the higher antioxidant activity than the ripened rice seed on lipids, which will improve FER using on the functional foods and help provide certainly theoretical basis in food processing industry.

A total of 101 local rice varieties, composted of 85 glutinous and 16 non-glutinous varieties grown in wet season 2016, were analyzed for tocopherols (TOC), tocotrienols (T3) and γ-oryzanol (Orz). Two popular varieties, RD6 and KDML105, were used as standard checks for glutinous and non-glutinous varieties, respectively. γ-TOC was found in all glutinous varieties (0.47-9.78 mg/kg), which were higher than RD6 (0.16 mg/kg). α-TOC was found in 40 varieties (1.02-6.29 mg/kg), only 6 varities were higher than RD6 (3.95 mg/kg). δ-T3 was found in 81 varieties (0.57-7.00 mg/kg), mostly varities were higher than RD6 (0.67 mg/kg). γ-T3 was found in all glutinous varieties (8.00-22.1 mg/kg), while RD6 contained 13.3 mg/kg. For α-T3, it was found in 39 glutinous varieties (1.52-9.94 mg/kg), mostly varities were higher than RD6 (2.62 mg/kg). Orz was found in all glutinous rice varieties (276-638 mg/kg), while RD6 contained 423 mg/kg. γ-TOC was found in all non-glutinous varieties (0.67-5.21 mg/kg), which were higher than KDML105. α-TOC was found in only 5 varieties (1.92-2.83 mg/kg), while KDML105 contained 2.23 mg/kg. δ-T3 was found in all non-glutinous varieties (1.64-8.87 mg/kg), which were higher than KDML105 (0.71 mg/kg). γ-T3 was also found in all non-glutinous varieties (8.80-17.58 mg/kg), while KDML105 contained 15.8 mg/kg. α-T3 was found in 9 non-glutinous varieties (4.56-8.93 mg/kg),while KDML105 contained only 0.86 mg/kg. Orz was also found in all those non-glutinous varieties (272-469 mg/kg), while KDML105 contained 469 mg/kg. These results indicate that γ-T3 was the highest vitamin E isomer present in all rice samples, while γ-TOC, α-TOC, δ-T3 and α-T3 were present in trace amounts. Orz was found in all local rice varieties.

Diabetes mellitus (DM) greatly impacts human health worldwide as over 400 million patients suffer from DM-related symptoms. Type 2 DM accounts for more than 90% of DM and is caused mainly by unhealthy lifestyles, such as high-calorie and high-fat diets. Such undesirable eating habitats induce resistance to insulin resulting in high blood sugar levels that cause induction of various symptoms and complications of DM. Therefore, management of blood sugar levels is important for preventing DM. Our group has recently found that rice (Oryza sativa L.) contains anti-diabetes compounds. Here, we summarize the effect of the bioactive ingredients in rice on preventing type 2 DM.

γ-Oryzanol (OZ), a functional substance found in rice bran, consists of multiple molecular species. In both in vitro and in vivo studies, the researches exploring the various function of rice bran OZ have been conducted for a long time, and it has become clear that OZ has a lot of pharmaceutical activities. It is assumed that each type of OZ molecular species may have different effects. In contrast, the profile behaviour of OZ inside the body has not been fully understood. This article reviews the previous studies about the digestion, absorption, metabolism, and effects of rice bran OZ and also introduces the new method to evaluate the OZ metabolic fate by using high-performance liquid chromatography (HPLC) combined with tandem mass-spectrometry (MS/MS) which has higher selectivity and sensitivity.

Rice (Oryza sativa) is one of the most important food crops in the world, and the effect of its consumption on human health is of great concern. Evidence has accumulated that rice contains several components, such as γ-oryzanol and rice bran fibers, which modulate the immune system. In addition, rice has other immunologically beneficial characteristics. It has a low allergenic potential and is gluten-free, reducing the risk of development of food allergies and diseases related to gluten sensitivity such as coeliac disease. This review presents the recent advances in our understanding of the immunomodulatory function of rice components.

Rice grain contains several functional compounds. Among these, γ-oryzanol is one of the most important owing to its biological role in human physiology. This study was conducted to determine the γ-oryzanol in Korean rice landraces, and classify them based on grain γ-oryzanol composition and contents. Ten fractions of γ-oryzanol were identified in the tested landraces with total γ-oryzanol contents ranging from 0.69 to 51.40 mg/100 g. Among individual components, 24-ethylene cycloartanyl ferulate, cycloartenyl ferulate, campesteryl ferulate and sitosteryl ferulate contributed to ∼90% of total γ-oryzanol with the highest values in landraces Paldado, Jaeraeryukdo, Ichun7ilchal and Dudo respectively, while △7-sitostenyl ferulate constituted only ∼0.30% of total γ-oryzanol. Korean rice landraces were classified in six groups based on oryzanol composition. Group 1 was glutinous rice with high oryzanol content (19.44 mg/100 g hulled rice), while group 2 had the lowest oryzanol content (9.57 mg/100 g hulled rice) with late maturation. Colored rice landraces included in group 5 had high oryzanol contents (17.02 mg/100 g hulled rice). Campesteryl ferulate contents were higher in non-glutinous rice. γ-oryzanol composition pattern can serve as basis for classification of Korean rice landraces, and for use in the breeding programs to develop γ-oryzanol rich rice cultivars.

High content of free fatty acids (FFA) in crude rice bran oil (CRBO) needs to be separated through deacidification. Generally, deacidification process that is widely used are chemical and physical processes which causes the loss of bioactive compounds (γ-oryzanol) and un-environmentally friendly. The liquid-liquid extraction (LLE) using deep eutectic solvents (DES) to remove FFA and preserve g-oryzanol would be implemented in this study. DES with different hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) with certain molar ratio such as Choline Chloride (ChCl)-Ethylene glycol 1:2 (DES I), ChCl-Glycerol 1:1 (DES II), ChCl-Urea 1:2 (DES III), ChCl-Oxalic acid 1:2 (DES IV), and Betaine Monohydrate-Glycerol 1:8 (NADES) were used as solvent to extract FFA from dewaxed/degummed RBO (DDRBO) for certain extraction time (30, 60, 120, 180, and 240 min) and extraction temperature (30°C, 40°C, 50°C, 60°C, and 70°C) under stirring (200 rpm). Deacidification using DES I for 240 min. and temperature of 50 °C was the optimum solvent to remove FFA (19.03 ± 2.33 %) and preserve g-oryzanol (recovery of g-oryzanol was 51.30 ± 1.77 %). The results also revealed that the longer time of extraction would be increased removal of FFA and decreased recovery of g-oryzanol. The higher temperature of extraction would be increased removal of FFA. In this work, temperature of 50 °C was the best extraction temperature of FFA since DES has highest solubility at this temperature.

The γ-oryzanol contents and the composition of steryl ferulates distributed in Japanese pigmented rice varieties were investigated using the high-performance liquid chromatography–ultraviolet detection method for the purpose of expanding their utilisation. The average γ-oryzanol content in nine black-purple, four red, four green and three brown rice varieties was 54.2, 47.3, 44.3 and 43.3 mg γ-oryzanol equivalent/100 g dried weight, respectively. Among the nine varieties of black-purple rice, five varieties showed steryl ferulate composition similar to that of brown, red and green varieties. In contrast, the composition of steryl ferulates in other four black-purple rice varieties was partially specific and was characterised by a low amount of campesteryl ferulate and high of campestanyl ferulate and stigmastanyl ferulate. The latter two steryl ferulates have been recognised as minor components of γ-oryzanol in rice and as major components in wheat and corn. These results indicate that the compositions of steryl ferulates vary among Japanese black-purple rice varieties. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-019-03767-w) contains supplementary material, which is available to authorized users.

This chapter summarizes the entire literature available on the nutritional value and diverse therapeutic potentials Gamma-oryzanol, a nutraceutical obtained from rice brain oil, composed of a mixture of γ - oryzanol, a mixture of ferulic acid esters of phytosterols and triterpenoids, cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, and campesteryl ferulate. In brief, the review covers the aspects such as the antioxidant mechanisms, effects on immune system, lipid disorders, diabetes, obesity and inflammation with the details of preclinical experiments, models and observations. Among the other highlights are the hepatoprotective, neuroprotective role in various neurological disorders such as Alzheimer’s, anxiety, Parkinson’s disease and wound healing effects. An overview of the sources, chemistry, physicochemical properties, pharmacokinetics and toxicity studies are also included.

Consumption of antioxidants rich rice has impressive health benefits. Five antioxidant traits viz., superoxide dismutase, flavonoids, anthocyanins, γ-oryzanol and ABTS were mapped in a panel population using 136 SSR markers through association mapping. A panel population containing 120 germplasm lines by including genotypes from all the phenotypic groups of the six antioxidant traits from the original shortlisted 270 rice genotypes. Donor lines rich in multiple antioxidant compounds were identified from the population. The population was classified into 4 genetic groups and showed fair degree of correspondence with the antioxidants content. A total of 14 significant marker-trait associations for antioxidants were detected of which 3 QTLs namely qANC3, qPAC12-2 for anthocyanin content and qAC12 for ABTS activity were validated in the population. Eleven putative QTLs such as qTAC1.1 and qTAC5.1 for anthocyanin content; qSOD1.1, qSOD5.1 and qSOD10.1 for SOD; qTFC6.1, qTFC11.1 and qTFC12.1 for TFC; qOZ8.1 and qOZ11.1 for γ-oryzanol and qAC11.1 for ABTS were detected to be novel loci. Co-localization of the QTLs detected for OZ11.1, TFC11.1 and AC11.1 regulating γ-oryzanol, flavonoid and anthocyanin content, respectively while PAC12.2 for anthocyanin content remained closer to TFC12.1 for flavonoid content. These QTLs will be useful in the antioxidant improvement programs in rice.

Background Rice bran oil is unique among edible oils owing to its rich source of commercially and nutritionally important phytochemicals, such as oryzanol. γ-Oryzanol performs an important role in the stability of rice bran oil. The crude rice bran oil obtained by solvent extraction is subjected to either chemical or physical refining to meet the specifications of edible-grade vegetable oil. These refining processes can cause the compounds present in rice bran oil to degrade. The aim of this study was to evaluate the stability of γ-oryzanol present in chemically and physically refined rice bran oils, when submitted to temperatures of 100, 140, and 180 °C for a period of 1368 h. Results The chemically refined rice bran oil presented a lower γ-oryzanol content than the physically refined rice bran oil at all heating temperatures. The losses of γ-oryzanol at 100 °C, 140 °C, and 180 °C at the end of the heating periods for the chemically refined oil were 53.47%, 58.48%, and 97.05% respectively, and for the physically refined oil the losses were 38.11%, 53.58%, and 91.11% respectively. Conclusion Based on the results of the time to reduce the oryzanol concentration by 50% and 100%, it is observed that the oil of rice meal refined physically presents greater stability, in the different temperatures studied and over time, than the oil of rice meal refined chemically. Thus, for situations where the oil needs to be subjected to prolonged heating, a temperature of 100 °C is indicated. In this condition, the physically refined oil is better for maintaining a higher concentration of γ-oryzanol. © 2021 Society of Chemical Industry.

Particulate matters (PMs) derived from are known to be responsible for a wide range of diseases. Recent studies have indicated that long-term exposure PMs is associated with several cardiovascular diseases, at least in part, by increase of inflammation, oxidative stress and nitric oxide (NO) balance disturbance. The present study was to investigate the protective effect of rice bran and its active compound, γ-oryzanol (γ-Orz), on PMs-induced premature endothelial senescence, and if then, to explore the underlying mechanism. Premature senescence was induced in porcine coronary arterial endothelial cells (PCAECs) by incubating 30 μg/mL of PM10. Senescence-associated β-galactosidase (SA-β-gal) activity, oxidative stress, expression level of cell cycle regulatory proteins, nicotinamide adenine dinucleotide phosphate(NADPH) oxidase, and local angiotensin system (LAS) component were evaluated. The result showed that senescence associated-β-gal activity in the PMs-treated PCAECs was attenuated by rice bran extracts (RBEs) and its major constituent, γ-Orz. Pretreatment with γ-Orz inhibited PMs-induced oxidative stress in PCAECs. Similarly, γ-Orz restored the cell proliferation of PCAECs by inhibiting PMs -induced cell cycle arrest. Western blot analyses revealed that cell cycle regulatory protein such as p53, p16, and p21 in senescent PCAECs treated with γ-Orz were reduced from PMs-exposed cells. In addition, γ- Orz prevented senescence associated NADPH oxidase, LAS activity of PM10-exposed cells. Pretreatment of γ-Orz restored PM10-induced endothelial dysfunction by upregulation of endothelial NO synthase expression. The present study demonstrated that γ-Orz protects against PMs induced PCAECs senescence, potentially through abrogating oxidative stress pathway. Taken together, this study can serve as a pharmacological use of rice bran extracts and γ-Orz for the prevention and/or treatment of air pollution-associated coronary artery diseases.

Background: Gamma-oryzanol (γ-oryzanol) is one of the rice bran oil (RBO) compounds, known as a principal food source throughout the world. In recent numerous experimental studies, γ-oryzanol has been revealed to have several useful pharmacological properties, such as anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, ameliorating unpleasant menopausal symptoms, cholesterol-lowering, improving plasma lipid pattern, etc. Methods: In this study, we reviewed the scientific literature published up until 2020, which has evaluated the biological and pharmacological activity of gamma-oryzanol. This review summarizes the published data found in PubMed, Science Direct, and Scopus. Results and Conclusion: The present review attempts to summarize the most related articles about the pharmacological and therapeutic potential from recent studies on γ-oryzanol to gain insights into design further studies to achieve new evidence that confirm the observed effects.

γ-Oryzanol is a naturally occurring component of rice bran and consists of various steryl ferulates. The antioxidant activities of γ-oryzanol have mostly been demonstrated in cell-free systems. Therefore, we determined whether steryl ferulate of γ-oryzanol suppress spontaneous intracellular reactive oxygen species (ROS) in cell-based systems. We found that cycloartenyl ferulate and β-sitosteryl ferulate suppressed spontaneous intracellular ROS in a similar way to N-acetylcysteine and α-tocopherol.

The rice industry is one of the most significant food industries since rice is a widely consumed cereal in the world. As a result of this substantial production, the rice industry has a significant amount of side streams, including bran, representing millions of tons of raw materials mainly designated to animal feed. Rice bran is a rich source of γ-oryzanol, a bioactive compound with substantial health benefits. In this perspective, different bran rice samples from distinct germplasm origins (Philippines, Italy and Portugal) were studied for their γ-oryzanol content by HPLC-PDA, cytotoxicity in four human tumour cell lines, hepatotoxicity in a normal cell line and for their antimicrobial effects on different bacterial and fungal strains. The Ballatinao sample presented the strongest activity against all the tumour cell lines, and was also the sample showing the highest amount of γ-oryzanol, suggesting its contribution to the exhibited cytotoxic properties. Regarding the antimicrobial activity, the tested samples were able to inhibit the majority of bacterial and fungal strains, with the Portuguese Ceres sample being the one presenting the highest bacterial inhibition and the Maluit and Dinorado samples, the highest fungal inhibition. Overall, the results show that rice bran extracts may be considered as potential candidates for antimicrobial agents when incorporated into food matrices. Ruaraid Hamilton from IRRI Philipines for supplying the rice seeds and Paula Marques from COTARROZ Portugal for multiplying the rice grain collection in COTARROZ greenhouses. Project POCI-01-0247-FEDER-017931 - ArrozBig - Development of rice products with low glycemic index and FCT SFRH/BD/120929/2016 PhD grant (Ana Castanho). The authors are grateful to the Foundation for Science and Technology (FCT. Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013) and R. Calhelha contracts. info:eu-repo/semantics/publishedVersion

In this study, purified rice bran oil (RBO) was used as a lipid matrix model to study the individual and binary antioxidant capacity of the minor constituents (α-tocopherol, γ-oryzanol and phytosterol) added at different concentrations and ratios. The results revealed that concentration influenced on the oxidation stability and scavenging capacity, while ratio mainly affected the type of interaction or the degree of synergism or antagonism. It was important to notice that the antioxidant capacity of α-tocopherol would decrease under high concentration. Besides, the inhibition of phytosterol on α-tocopherol and the formation of hydrogen bond between γ-oryzanol and phytosterol were speculated by the interactions of these minor constituents. This work helps to select efficient combinations for stabilizing the anti-oxidation of nutrient enriched RBO or provide suggestions for moderate retain of minor constituents in RBO.

In this study, the triacylglycerol structure of vegetable oils was removed and the effects of this removal were observed on the antioxidant efficiency of γ-oryzanol. A sigmoidal-model was used for calculating kinetic parameters relevant to the initiation and propagation phases during the peroxidation of soybean, corn, sesame, and olive oils as well as their fatty acid methyl esters. Removing the triacylglycerol structure caused an increase in the antioxidant activity of γ-oryzanol (26.49%) by affecting both inhibitory mechanisms, i.e. hydrogen-donating (7.80%) and electron-transfer (14.72%). Unexpectedly, the antioxidant performance of γ-oryzanol continued even when the induction period had ended. During the propagation phase, the highest antioxidant activity was observed in the fatty acid methyl esters of soybean oil (3.86) based on hydroperoxides decomposition. An evaluation of how the endergonic activated complexes formed could indicate that the removal of the triacylglycerol structure increased the effective collisions between the γ-oryzanol molecules and free radicals.

γ-Oryzanol contained as a minor component in rice bran oil (RBO) is a group of phytosterol ferulates. The existence of γ-oryzanol in rice bran oil is very interesting because of the special biological functions. The methods to determine γ-oryzanol in crude RBO include the absorptiometry, thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). However, those methods need much solvent and long operating time. Moreover, some of those methods are not able to apply to refined RBO because of the low sensitivity. We have developed the method to determine γ-oryzanol in refined RBO using proton nuclear magnetic resonance (1H-NMR). Refined RBO had a specific chemical shift due to the methoxy group of ferulate in γ-oryzanol at 3.9 ppm on the 1H-NMR spectrum. The intensity of the chemical shift due to the methoxy group of ferulate was consistent with the amounts of γ-oryzanol in refined RBO. This NMR method was able to quickly and easily determine γ-oryzanol in refined RBO.

The present study's author investigated the interactions of three minor constituents (α-tocopherol, γ-oryzanol, and phytosterol) with different concentrations or proportions in refined coconut oil (CNO), which was full of medium-chain saturated triglycerides. Antioxidant properties of individual and combined minor constituents were determined through rancimat method and DPPH• scavenging capacity assay, and the interaction types among three minor constituents were evaluated. The results revealed that their interaction types were distinct from other oil bases with different chain lengths and saturation of triglycerides. Antioxidant interaction of these three minor constituents in refined CNO was mainly synergistic. The antioxidant capacities generally increased upon concentration of combinations, and the types of antioxidant interaction were related to their proportion.

Leum Pua is native Thai glutinous rice that contains antioxidants higher than white rice and other colored rice. One of the major antioxidants in rice brans is γ-oryzanol (GO). In this study, Leum Pua glutinous rice bran was extracted by different solvents. Oleic acid (~40 g/100 g extract), linoleic acid (~30 g/100 g extract), and palmitic acid (~20 g/100 g extract) were found to be major lipid components in the extracts. Methanol extract showed less variety of lipid components compared to the others. However, hexane extract showed the highest percent of γ-oryzanol compared to other solvents. Therefore, the hexane extract was selected to prepare nanostructured lipid carriers (NLC). The prepared NLC had small particles in the size range of 142.9 ± 0.4 nm for extract-loaded NLC and 137.1 ± 0.5 nm for GO-loaded NLC with narrow size distribution (PI < 0.1) in both formulations. The release profile of extract-loaded NLC formulation was slightly higher than GO-loaded NLC formulation. However, they did not follow the Higuchi model because of small amounts of γ-oryzanol loaded in NLC particles.

Normal brain functioning involves the interaction of interconnected molecular and cellular activities, which appear to alter normal to abnormal brain functioning when worsened, contributing to the emergence of neurological disorders. There are currently millions of people who are living with brain disorders globally and this will rise if suitable prevention strategies are not explored. Nutraceutical intended to treat numerous health goals with little adverse effect possible together can be more beneficial than pharmaceutical monotherapy for fostering balanced brain functioning. Nutraceutical provides a specific composition of effective macronutrients and micronutrients that are difficult to synthesize in the laboratory. Numerous elements of rice fibers in rice bran are characterized as natural anti-oxidant and having potential anti-inflammatory activity. The rice bran captures interest among the researchers as it is widespread, affordable, and rich in nutrients including protein, fat, carbohydrates, bioactive components, and dietary fiber. This review covers the neuroprotective multiplicity of rice bran and its constituents to deter pathological conditions of the brain and to facilitate balanced brain functioning at the same time.

Cyclooxygenase (COX)-2 produces prostanoids, which contribute to inflammatory responses. Nuclear factor (NF)-κB is a key transcription factor mediating COX-2 expression. γ-Oryzanol is an active component in rice bran oil, which inhibits lipopolysaccharide (LPS)-mediated COX-2 expression by inhibiting NF-κB. However, the inhibition of COX-2 expression by γ-oryzanol independently of NF-κB is poorly understood. We found that LPS upregulated Egr-1 expression at the transcriptional level. Forced expression of Egr-1 trans-activated the Cox-2 promoter independently of NF-κB. In contrast, silencing of Egr-1 abrogated LPS-mediated COX-2 expression. LPS produced reactive oxygen species (ROS), which, in turn, induced Egr-1 expression via the Erk1/2 MAPK pathway. ROS scavenging activity of γ-oryzanol suppressed Egr-1 expression by inhibiting the Erk1/2 MAPK pathway. Our results suggest that γ-oryzanol inhibits LPS-mediated COX-2 expression by suppressing Erk1/2-mediated Egr-1 expression. This study supports that γ-oryzanol may be useful for ameliorating LPS-mediated inflammatory responses.

Oil migration in filled pralines is a phenomenon that is highly correlated with the occurrence of chocolate bloom. In this study the potential to suppress or prevent oil migration by incorporation of sterol/sterolster-structured organogels was evaluated. Different quantities, 2.5 or 14% (w/w), of gel with structurant levels of either 10 or 25% (w/w) were studied in a layered model system. The gel was either a part of the nougat or of the chocolate phase, or as a separate layer. Samples were monitored regularly for a period of 24 weeks at storage temperatures of 10, 18 and 28 °C. The amount of migrated oil was determined via DSC analysis of a surface sample. The results indicate that, despite the additional oil brought into the system via the oleogel, the level of oil found in the chocolate layer is reduced through the presence of the gel. In particular, the three-layer system and gelled chocolate appear to be promising routes to either suppress oil migration or improve nutritional profiles by incorporation of liquid oils.

Rheology and atomic force microscopy (AFM) were employed to examine the microstructure of β-sitosterol:γ-oryzanol organogels in sunflower oil. Using time-resolved rheology, we followed gel formation, paying specific attention to the fibril aggregation process, which had not been studied in detail previously for this system. Using AFM, we observed gel structures directly and obtained detailed information on the gel structure, far exceeding previous studies. Our analysis suggests that though gels are formed by the self-assembly and aggregation of one-dimensional fibrils, the manner in which these fibrils aggregate into ribbons results in complex structures of higher dimensionality. We emphasize that it is a surprise to find ribbons and not twisted strands. Comparing AFM images of 10% w/w and 20% w/w gelator systems, we observed differences in the degree of branching which are consistent with the rheology. We also observed the individual self-assembled fibrils which make up these gels with much greater clarity than in previous microscopy studies, and the fibril diameters of ∼9.8 nm we measured agree excellently with those obtained from existing small-angle neutron scattering data. These results provide new insight into the structure and formation kinetics of this important organogel system.

β-Sitosterol and γ-oryzanol have reduced solubility in aqueous based formulations. In this study β-sitosterol (β-st) and γ-oryzanol (γ-oz) were encapsulated at relatively high concentrations in different food-grade oil-in-water (O/W) emulsions using straight-through microchannel emulsification. The innovative aspect of this study was the production of monodisperse droplets with high encapsulation efficiency and stability of β-sitosterol and γ-oryzanol. Milli-Q water containing 1% (w/w) Tween 20 or decaglycerol monolaurate (ML-750) was used as the continuous phase and the dispersed phase contained 0.5–4% (w/w) each of β-st and γ-oz in medium chain triglycerides. Successful droplet generation was conducted with different concentrations of β-st and γ-oz. The Sauter mean diameter of 1% (w/w) β-st and γ-oz loaded O/W emulsions ranged between 26 and 28 μm with relative span factor width below 0.21. These emulsions were stable at 4 and 25 °C during evaluated storage period. The emulsions stabilized with Tween 20 have encapsulation efficiencies of β-st and γ-oz (EEβ-st and EEγ-oz) above 80% at 4 and 25 °C; those stabilized with ML-750 have EEβ-st over 80% and EEγ-oz above 50% at 4 and 25 °C.

Made available in DSpace on 2019-10-06T16:15:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-15 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Rice bran (RB) is a rice milling by-product and an interesting source of fibers and bioactive compounds as γ-oryzanol. These food compounds are capable of prevent and/or improve metabolic disorders associated to chronic diseases. To provide a good source of bioactive compounds and a better destination for RB, the aim of this study was to develop and evaluate the antioxidant potential of functional cookies made with this by-product. Five different formulations containing 25, 50, 75 and 100% of RB were studied and, in the control formulation, RB was substituted by polished rice flour. Cookies were analyzed up to 30 days of storage, regarding the levels of fibers, γ-oryzanol and lutein. The antioxidant capacity was determined through DPPH ● and FRAP assays. The shelf life was determined through microbiological analyses and the acceptance was evaluated by means of hedonic scale acceptance test and purchase intention test. There was a significant difference (p < 0.05) among the formulations regarding the fibers content, γ-oryzanol, lutein and antioxidant capacity, which values increased according to the RB content in the composition. Sensory analysis showed a higher acceptance of the formulations with RB the control cookies, with preference for the cookie containing 75% of RB. Cookies containing RB can be produced at low cost, becoming accessible to consumers, and provide an effective alternative to improve the population nutrition and the utilization of this by-product. Department of Education Institute of Bioscience São Paulo State University - UNESP Department of Chemistry and Biochemistry Institute of Bioscience São Paulo State University - UNESP Department of Agri-food Industry Food and Nutrition University of São Paulo - USP Department of Pathology Faculty of Medicine São Paulo State University - UNESP Department of Biological Science Centro Universitário Sudoeste Paulista - UNIFSP Department of Education Institute of Bioscience São Paulo State University - UNESP Department of Chemistry and Biochemistry Institute of Bioscience São Paulo State University - UNESP Department of Pathology Faculty of Medicine São Paulo State University - UNESP FAPESP: 2016/22665-2 CNPq: 305177/2015-0

&gamma, Oryzanol (OZ), a bioactive phytochemical abundant in cereals such as rice, has been reported to be mainly hydrolyzed to ferulic acid (FA) in the body. Meanwhile, in our previous study, we revealed that a part of OZ is absorbed into the body and exists in its intact form. However, the comprehensive absorption profile of OZ and its metabolites (e.g., FA) after OZ intake has not been fully elucidated yet. Therefore, in this study, we measured the concentrations of OZ, FA, and FA conjugates (i.e., FA sulfate and glucuronide) in the blood of rats with the use of HPLC-MS/MS after a single oral administration of 300 &micro, mol/kg body weight of rice bran OZ (RBOZ). As a result, intact OZ along with FA and FA conjugates existed in the blood, which implied that these constituents may all contribute to the physiological effects under OZ intake. Additionally, when an equimolar amount of FA (300 &micro, mol/kg body weight) was administered, it was found that the absorption profile of FA was significantly different from that when RBOZ was administered.

Self-emulsion improves solubility and bioavailability for &gamma, oryzanol/algae oil, and alginate beads can be used as controlled release carriers. In this study, self-emulsified alginate beads (SEABs) were prepared with different weight ratios of self-emulsion treatment (5%, 10%, 15%, 20%, and 30%) with alginate. We found that the microstructure with a surfactant of SEABs had a different appearance with alginate-based beads. The encapsulation of &gamma, oryzanol corresponded with the self-emulsion/alginate ratio, which was 98.93~60.20% with a different formulation of SEABs. During in vitro release, SEABs had the gastric protection of &gamma, oryzanol/algae oil, because &gamma, oryzanol and emulsion were not released in the simulated stomach fluid. When the SEABs were transferred to a simulation of the small intestine, they quickly began to swell and dissolve, releasing a higher content of the emulsion. We observed that the emulsion that formed had a bimodal distribution in the simulated intestinal fluid as a result of the hydrogel and emulsion droplets, leading to the formation of large aggregates. These results suggested that &gamma, oryzanol encapsulation within alginate beads via emulsification combined with gelation can serve as an effective controlled delivery system.

We demonstrate that γ-oryzanol at concentrations as low as 7 wt% can structure vegetable oil. At a temperature below its crystallization onset, quiescent processing does not result in oil structuring, given the formation of γ-oryzanol crystal spherulites upwards of 100 μm in diameter that do not associate to form a continuous network. Rather, concurrent mixing and cooling are necessary to form a γ-oryzanol enmeshed crystal network. At both ‘low’ (50 rpm) and ‘high’ (700 rpm) mixing rates, network formation occurs, with the higher rate resulting in platelet crystals a few microns in length and the equilibrium solids content being reached within the preparation timeframe of 1 h. For a given mixing and cooling regime, higher γ-oryzanol contents increase the resistance to melting, elastic modulus and hardness. Overall, this study reveals that γ-oryzanol can single-handedly structure vegetable oil if appropriate combined mixing and cooling are used.

Even though γ-oryzanol (OZ) such as 24-methylenecycloartanyl ferulate (24MCAFA) is abundant in purified rice bran oil, we realized that the oil contained the prospect of two additional novels of OZ species. To identify this, we isolated and analyzed their chemical structures by using HPLC-UV-MS, NMR, and IR. We revealed for the first time that the oil had also contained cyclobranyl ferulate (CBFA) and cyclosadyl ferulate (CSFA) which are likely to be exist due to the isomerism of 24MCAFA under acid condition. OZ profile including CBFA and CSFA was roughly similar between commercial rice bran oils and processed foods containing the oils, suggesting that people might have often consumed CBFA and CSFA from rice bran oils and/or processed foods. Since different OZ species are known to have different functionality, this study opens the chance to explore more the contribution of CBFA and CSFA for human health and wellness.

A 90-day oral toxicity study of γ-oryzanol, a rice-derived triterpenoid ferulate, was performed by oral gavage administration to male and female Sprague-Dawley rats at doses of 0, 1000, and 2000 mg/kg body weight/day. All rats administered γ-oryzanol survived throughout the study period. Both male and female rats showed no toxicologically significant changes of the general signs, examination findings, body weight, food consumption, functional observational battery results, ophthalmological findings, urinalysis, hematology tests, clinical chemistry tests, organ weights, and necropsy findings. Moreover, there were no histopathological changes related to administration of γ-oryzanol in males and females from the 2000 mg/kg body weight/day group. In conclusion, the no observed adverse effect level (NOAEL) of γ-oryzanol exceeded 2000 mg/kg body weight/day for both male and female rats under the conditions of this study. Keywords: γ-Oryznaol, Rice, Rat, Repeated-dose oral toxicity study, NOAEL

Sunflower oil organogels and their emulsions were incorporated in frankfurters to partially replace pork backfat. Nine frankfurter treatments were made with 20% total fat content. Control treatment contained 20% pork backfat and the other eight treatments were formulated with 10% pork backfat and 10% structured sunflower oil in the form of organogels or organogel-in-water emulsions (made with various ratios of γ-oryzanol and phytosterols). No differences in the pH and oxidation levels of the frankfurters were detected. Minor differences were detected in the colour parameters L*, a* and b*. Texture profile analysis showed that frankfurters with organogels were no different from the control in any textural parameter, while treatments with emulsions had lower chewiness, hardness and gumminess values. Sensory analysis showed that all treatments had similar overall acceptability with the control, except for the some emulsion treatments that had lower acceptability. Pork backfat can be partially replaced by organogels, without considerably affecting the overall physicochemical and sensorial properties of the frankfurters.