A rapid procedure for analysing rice bran tocopherol, tocotrienol and γ-oryzanol contents

Nutrients in rice bran oil and their nutritional functions: a review

Rice is an important food crop throughout the world. Rice bran, the outer layer of rice grain, is a by-product generated during the rice milling process. Rice bran oil (RBO) is extracted from rice bran and has also become increasingly popular. RBO is considered to be one of the healthiest cooking oils due to its balanced proportion of fatty acids, as well as high content of γ-oryzanol together with phytosterols, vitamin E, wax ester, trace and macro elements, carotenoids, and phenolics. The existence of these compounds provides RBO with various functions, including hypotensive and hypolipidemic functions, antioxidant, anticancer, and immunomodulatory functions, antidiabetic function, anti-inflammatory and anti-allergenic functions, hepatoprotective activity function, and in preventing neurological diseases. Recently, research on the nutrients in RBO focused on the detection of nutrients, functions, and processing methods. However, the processing and utilization of rice bran remain sufficiently ineffective, and the processing steps will also affect the nutrients in RBO to different degrees. Therefore, this review focuses on the contents and nutritional functions of different nutrients in RBO and the possible effects of processing methods on nutrients.

The potential use of Indian rice flour or husk in fortification of pan bread: assessing bread's quality using sensory, physicochemical, and chemometric methods

Hassawi rice is an Indica variety cultivated in Saudi Arabia with a higher nutritional value than the commercial Basmati rice varieties. The present study has investigated the feasibility of combining Hassawi rice flour (HRF) or husk (HRHF), an abundant byproduct, with wheat flour to produce nutritious economical pan bread. To achieve this aim, the physicochemical properties of HRF and HRHF were assessed using techniques such as UPLC-tandem MS, ICP-OES, and colorimeter. The proximate composition (moisture, crude fiber, and ash) and mineral contents of HRHF are significantly (p < 0.05) higher than HRF. On the other hand, the compounds p-coumaric acid, vanillic acid, γ- and δ-tocotrienols, and γ-oryzanol were unique to HRF. We further determined the changes in sensory, technological, and physicochemical properties of wheat flour bread substituted with 5%, 10%, and 15% of HRF or HRHF. The rheological tests showed that the addition of HRF and HRHF increased dough development and stability time. Further, substituting wheat flour for HRF and HRHF at levels higher than 10% affected sensory attributes, such as color, taste, odor, flavor, and appearance. These changes, however, were not always at a significant level. The causes of the differences in properties between control and fortified bread samples were investigated by chemometric methods. Samples of bread + HRF at 5 and 10% had comparable overall profiles to the control. On the other hand, bread + HRHF samples proved to retain higher concentrations of bioactive molecules compared to the control bread. Our findings shed light on the possible use of rice husk fibers in baking goods, notably pan bread. Furthermore, by integrating rice husk fibers into baked goods, we may boost their health benefits while also contributing to the long-term use of agricultural waste.

Evaluation of Roasting and Grilling Effects on Chemical Composition, Volatile Profiles, and Toxicity of Stink Bugs (Tessaratoma papillosa): Implications for Utilization as Functional Food Ingredients

The stink bug (Tessaratoma papillosa) is a highly popular edible insect in Thai traditional cuisine, but little research has investigated the effects of heat treatment on the quality of stink bugs. Therefore, we aimed to evaluate the effects of roasting and grilling on the chemical changes and volatile compounds of late nymph and adult stink bugs. In general, all treated samples showed increases in phenolic acid, tocopherols, and amino acid contents and a decrease in the content of fiber compared with raw stink bugs (p < 0.05). Cinnamic acid significantly increased by over 200% in late nymph insects and 30% in adult insects after roasting, whereas syringic acid decreased after cooking (p < 0.05). The most predominant volatile compound found in all samples was 5-methyl-octadecane and it decreased after cooking, while volatile alkane compounds increased after cooking. The processed sample extracts showed higher toxicity on oral cancer KB and cervical cancer Hela cells than on Vero cells. We have demonstrated that different cooking methods affected the chemical components which may result in quality attributes if stink bug is to be used as a functional ingredient/food. It may be helpful to improve the nutritional and functional values of stink bugs during deep processing.

Nutritional Compositions, Phenolic Contents and Antioxidant Activities of Rainfed Rice Grown in Different Degrees of Soil Salinity

Rice (Oryza sativa) is a staple food crop for over half of the world's population. However, drought as a result of climate change has led to increased soil salinity, thereby reducing agricultural potential, especially rice nutritional compositions and biochemical properties. Nevertheless, soil management by using suitable fertilizers might be able to improve rice quality even though these rice samples were grown in soil with a high degree of salinity. This study investigated nutritional compositions, phenolic contents, and antioxidant activities of twenty-five rainfed rice samples in Khao Dawk Mali 105 (KDML105) and Rice Department 15 (RD15) varieties grown in soil with different degrees of salinity. The soil, however, had been improved by the usage of fertilizer at the tillering and booting stages. Results indicated that all rice samples exhibited similar nutrients, total phenolic contents (TPCs), and antioxidant potentials, suggesting that appropriate fertilizer could improve rice qualities. Principle Component Analysis (PCA) and Pearson correlation results suggested that regardless of rice varieties, organic matter (OM) and soil potassium (Ks) showed a very strong positive correlation with protein and minerals (Ca, Na, K, and Fe), while opposite results were observed with soil pH. Moderate to very weak correlations were also observed between soil parameters and TPCs, as well as between soil parameters and antioxidant activities. The received information will be useful for the future development of appropriate fertilizer usage in salt-tolerant rice with particular nutritional quality.

Optimization of Enzyme-Assisted Mechanical Extraction Process of Hodgsonia heteroclita Oilseeds and Physical, Chemical, and Nutritional Properties of the Oils

Hodgsonia heteroclita subsp. Indochinensis W.J.de Wlide & Duyfjes (or Making in Thai) is a neglected and underutilized crop (NUC) with high fat containing nuts. In this study, the enzyme-assisted mechanical extraction of H. heteroclita seed oil was investigated using response surface methodology (RSM) to predict the optimal fat extraction conditions. The most efficient enzyme used in the experiment was a mixture of Flavourzyme^® and Viscozyme^® (1:1, w/w). The predicted maximum oil yield was 46.44%, using the following extraction conditions: 2.98% (w/w) enzyme loading, 48 °C incubation temperature and 76 min of incubation time. H. heteroclita seed oil obtained from heat and enzymatic pretreatments exhibited the highest lightness and viscosity. The chemical properties of this seed oil, including water and volatile compounds (≤0.2% w/w), acid value (≤4.0 mg KOH/g), peroxide value (≤15 mEq of active oxygen/kg) and soap content (≤0.005% w/w), were within the acceptable levels specified by the Codex Alimentarius (2019). H. heteroclita seed oil obtained from heat and enzymatic pretreatments contained the highest content of δ-tocopherol (88.29 mg/100 g) and omega-6 fatty acids (48.19 g/100 g). This study is the first to report on the enzyme-assisted mechanical extraction of H. heteroclita oilseeds as a promising plant material for vegetable oil production.

From farm to plate: Spatio-temporal characterization revealed compositional changes and reduced retention of γ-oryzanol upon processing in rice

Background

Antioxidants detain the development and proliferation of various non-communicable diseases (NCDs). γ-oryzanol, a group of steryl ferulates and caffeates, is a major antioxidant present in rice grain with proven health benefits. The present study evaluated the distribution and dynamics of γ-oryzanol and its components in spatial and temporal scales and also delineated the effect of processing and cooking on its retention.

Methods

Six rice varieties (four Basmati and two non-Basmati) belonging to indica group were analyzed at spatial scale in four different tissues (leaf blades, leaf sheaths, peduncle and spikelets) and temporal scale at three developmental stages (booting, milky and dough). Additionally, the matured grains were fractioned into husk, embryo, bran, and endosperm to assess differential accumulation in these tissues. Further, milling and cooking of the samples was done to assess the retention upon processing. After extraction of γ-oryzanol by solvent extraction method, individual components were identified by UPLC-QToF-ESI-MS and quantified by RP-HPLC.

Results

The non-seed tissues were significantly different from the seed tissues for composition and quantitative variation of γ-oryzanol. Cycloartenyl caffeate was predominant in all the non-seed tissues during the three developmental stages while it showed significant reduction during the growth progression toward maturity and was totally absent in the matured grains. In contrary, the 24-methylenecycloartanyl ferulate, campesteryl ferulate and β-sitosteryl ferulate showed significant increment toward the growth progression to maturity. Milling caused significant reduction, retaining only an average of 58.77% γ-oryzanol. Cooking of brown rice in excess water showed relatively lower average retention (43.31%) to samples cooked in minimal water (54.42%). Cooked milled rice showed least mean retention of 21.66%.

Conclusion

The results demonstrate prominent compositional variation of γ-oryzanol during different growth stages. For the first time, the study demonstrated that ferulate esters of γ-oryzanol were predominant in the seed tissues while caffeate esters were dominant in non-seed tissues. Basmati cultivars show differential expression of γ-oryzanol and its components compared to non-Basmati cultivars. Cooking in excess water causes maximum degradation of γ-oryzanol. Post-harvest losses due to milling and cooking indicate the necessity of biofortification for γ-oryzanol content in rice grain.

Phytochemical Profile and Chemopreventive Properties of Cooked Glutinous Purple Rice Extracts Using Cell-Based Assays and Rat Model

Purple rice has gained attention for its health promoting potential due to a high content of bioactive phytochemicals. The heat generated during cooking alters the quality and quantity of nutrients and phytochemicals in food. This study aimed to investigate the phytochemical profile and chemopreventive properties of cooked glutinous purple rice using cell-based assays and a rat model. Purple rice was cooked in a rice cooker and was then further extracted with solvents to obtain dichloromethane and methanol extracts. The methanol extracts of glutinous purple rice contained great amounts of phenolics, flavonoids, and anthocyanins. Protocatechuic acid (2.26–5.40 mg/g extract) and cyanidin 3-glucoside (34.3–65.7 mg/g extract) were the major phenolic acid and anthocyanin contents, respectively. After cooking, the content of anthocyanins, γ-oryzanols, and phytosterols decreased, while the amount of some phenolic acid and tocol contents increased. Methanol extracts of glutinous purple rice inhibited reactive oxygen species production about 60% in PMA-treated peripheral blood mononuclear cells, reduced nitric oxide formation in LPS-induced RAW 264.7 cells (26–39% inhibition), and exhibited antimutagenicity against several mutagens using the Ames test, but dichloromethane extracts presented only mild anti-inflammatory activities. Although methanol extracts induced mild mutagenicity (mutagenic index 2.0–2.5), they did not induce micronucleated hepatocyte formation and certain hepatic CYP450 isozyme activities in rats. However, the mutagenicity of the methanol extract significantly declined after cooking. In summary, the methanol extract of the cooked glutinous purple rice might be a promising cancer chemopreventive fraction, which was neither genotoxic nor posing adverse effects on phytochemical–drug interaction in rats.

Retention of bioactive compounds during extrusion processing and storage

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Significant retention of beta-glucans was reported in fortified extrudates.

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Lowest rentention was found in extrudates fortified with oryzanol at high level.

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In storage studies at higher relative humidities, lowest retention was observed.

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L* and b* values decreased when extrudates were kept at high relative humidities.

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a* value increased when extrudates were kept at high relative humidities.

Retention of bioactive compounds (beta-glucans, lignans and gamma oryzanol) was analyzed after extrusion and during storage period of three months under four relative humidities using saturated salt solutions such as potassium carbonate (43.26%), magnesium nitrate (52.60%), potassium chloride (84.36%) and potassium nitrate (93.58%). The control sample comprising a corn and rice flour blend (50 g each) was substituted with beta-glucans at 3 g/100 g and 6 g/100 g, flaxseed lignans at 6.67 g/kg and 11.67 g/kg and gamma oryzanol at 1.5 g/100 g and 3.0 g/100 g at low and high levels, respectively. After extrusion, beta-glucan was retained up to 82.67 and 90.83%, lignans were retained at 86.31 and 66.66% whereas retention of gamma oryzanol was 71.33 and 51.67% at low and high level of substitution, respectively. Retention of bioactive compounds was the lowest along with a decrease in L* and b* values and an increase in a* value was observed under higher relative humidity (84.36% and 93.58%) storage conditions.

A novel LOX3-null allele (lox3-b) originated in the aromatic Basmati rice cultivars imparts storage stability to rice bran

Rapid deterioration of rice bran due to the LOX3 enzyme catalysed oxidation of PUFA is the major bottleneck for its utilization in various downstream applications. In the present study, we have identified a set of nine novel LOX3-null rice accessions carrying a deletion of C residue in the exon2 causing a frameshift mutation resulting in a truncated non-functional LOX3 protein. Our study, further manifested the predominance of C deletion based LOX3-null allele, named lox3-b, in the aromatic rice germplasm particularly in the Indian Basmati rice group. The LOX3-null genotypes exhibited significantly reduced rancidity, after six months of storage. They also showed significantly lower percentage reduction of linoleic acid (LA), higher γ-oryzanol content and lower hexanal content. A functional dCAPS marker designed based on the deletion polymorphism clearly differentiated LOX3 and lox3-b alleles, and has the potential application in marker assisted rice breeding programmes to develop cultivars with better bran storability.

Pressurized liquid extraction to obtain chia seeds oils extracts enriched in tocochromanols. Nanoemulsions approaches to preserve the antioxidant potential

The objective of this study was to use accelerated-solvent-extraction to achieve antioxidant extracts from chia seeds oils, enriched in tocopherols and tocotrienols, namely tocochromanols. Nanotechnology applications have been also incorporated to develop an innovative formulation of chia seeds oil nanoemulsion that preserve its antioxidant potential after conditions of oxidative stress. Chia seeds oils proved to be a valuable source of tocochromanols, from 568.84 to 855.98 μg g^-1, depending on the geographical provenance. Quantitative data obtained by LC-DAD-ESI-MS/MS showed outstanding levels of γ-Tocopherol, over 83%, followed far behind by Tocopherols-(α, β, δ) and Tocotrienols-(α, β, δ, γ)-tocotrienols. The characteristic tocochromanols fingerprint of chia seeds oils was positively correlated with the FRAP and DPPH antioxidant activity of the extracts (between 18.81 and 138.48 mg Trolox/g). Formulation of the Chia seeds oils as nanoemulsions did not compromised the antioxidant properties of fresh extracts. Interestingly, nanoemulsions retained about the 80% of the initial antioxidant capacity after UV-induced stress, where the non-emulsified oils displayed a remarkable reduction (50-60%) on its antioxidant capacity under the same conditions. These antioxidant chia seeds formulations can constitute a promising strategy to vectorizing vitamin E isomers, in order to be used for food fortification, natural additives and to increase the self-life of food products during packing.

Influence of enzyme concentrations in enzymatic bioprocessing of red rice bran: A detailed study on nutraceutical compositions, antioxidant and human LDL oxidation inhibition properties

Enzymes and their concentrations are crucial factors in improving the release of nutraceuticals bounded to rice bran's cell wall matrix. This study aims to investigate the optimal concentrations of Viscozyme and Fiberzyme at 3-30 beta-glucanase units/2 g in improving the release of phenolics, tocopherols, tocotrienols, and γ-oryzanol fractions and enhancing the bioactivities of red rice bran. At specific concentrations, Fiberzyme increased ferulic (301%) and caffeic acid (691%) in soluble phenolics, p-coumaric acid (98%), and catechin (161%) in bound phenolics as well as γ-oryzanol fractions(32%-134%) and increased ferric reducing power (90%), DPPH (41%), and hydroxyl (25%) radical scavenging activities. Viscozyme enhanced δ,γ,α-tocopherols (11%-164%) and tocotrienols (39%-271%) and scavenging activities against nitric oxide (144%), superoxide anion (120%), and inhibition of human LDL oxidation (40%). Cycloartenyl ferulate, ferulic acid, soluble phenolics, campesteryl ferulate, 24-methylenecycloartanyl ferulate, and α-tocotrienol showed a significant positive correlation with bioactivities. Thus, optimization of enzymatic processing will help process the red rice bran into a nutraceutical rich ingredient having higher biological activity.

Cyclodextrin glycosyltransferase-treated germinated brown rice flour improves the cytotoxic capacity of HepG2 cell and has a positive effect on type-2 diabetic mice

Germinated brown rice (GBR) consists of bioactive compounds (BCs) that are very useful for diabetes treatment. Modified GBR-based flour (MGBRF) was produced by modifying the starch in GBR with 0, 299.19, 598.38, and 897.57 U/ml of cyclodextrin glycosyltransferase (CGTase) for 1 hr and then spray-dried to examine its antidiabetic and cytotoxic effects. The results showed that the slowly digestible starch and resistant starch by modifying the starch in GBR with 598.38 U/ml of CGTase were 55.8% and 5.92% corresponding to the increase of γ-amino butyric acid (GABA) and ferulic acid (FA) with 4.31 ± 0.68 mg/ml and 3.10 ± 0.02 mg/ml, respectively. The extract from MGBRF showed strong cytotoxic capacity against HepG2. Furthermore, the in vivo study revealed the stability of the glycemic index (GI) by consuming MGBRF with significant impacts on diabetes. These results suggest that MGBRF through the action of CGTase plays a major role in antidiabetes and HepG2 cell product value addition. PRACTICAL APPLICATIONS: GBR consists of BCs that are useful for diabetes and cancer treatment. However, when using this or GBR-based products, it is difficult to evaluate the effect of functional properties, especially for diabetes and/or cancer diseases due to high starch content. Therefore, the modification of starch to limit digestible starch, increase SDS and RS as well as to enhance the effect of BCs on diabetes and cytotoxic activity on cancer cell should be studied before producing various based products from GBR. The results in this study indicated that CGTase increased BCs without any glycosides BCs in the extract. The MGBRF changed to higher RS and SDS while increasing the BCs. The extract of MGBRF showed strong cytotoxic activity against HepG2 cell and a positive effect on type 2-diabetic mice. Hence, this study produces new information for effective use of GBR-based food as a functional food.

Enzymatic preparation of structured TAG containing conjugated linoleic acid (CLA) at solvent-free

Rice bran oil extracted by the water-enzymatic method was placed at a temperature of −5 °C for 8 h. Light-phase rice bran oil with an iodine value of 112.13 ± 0.21 g I2/100 g oil was separated by cryogenic freezing centrifugation. Lipozyme RM IM transesterified light-phase rice bran oil and conjugated linoleic acid (CLA) under supercritical system CO2 (SC-CO2). The optimal reaction conditions for transesterification of CLA and rice bran oil in SC-CO2 were determined as follows: the Lipozyme RM IM dosage was 9%, and the RBO/CLA molar ratio was 1:3, the reaction temperature was 55 °C, stirring speed was 300 rpm, and transesterification time was 20 h, the CLA conversion rate can reach 42.1%.

Impact of roasting conditions on the quality and acceptance of the peanut paste

Roasting is the main processing step performed to improve sensory and conservative properties of peanuts. The objective of this study was to evaluate changes in peanut oil and paste during roasting at different temperatures in a conventional oven (80, 110, 140, 170, and 200°C) and microwave. The increase in roasting temperature promoted reduction of L* value, b* value, and increases of a*, K₂₃₂ , K_270, and acidity. For alpha (α), gamma (γ), and delta (δ) tocopherols, as well as fatty acids, less degradation were observed at the roasting temperature of 140°C. Paste acceptability greater than 70% was achieved with roasting at 140°C. Based on the results, 140°C was the optimal roasting temperature that achieved the best paste acceptance rates with the smallest changes in oil and tocopherol quality parameters.

INVESTIGATING THE ANTIOXIDANT PROPERTIES OF IRANIAN CHILI PEPPER EXTRACT

Stress oxidative factors are known to causes diseases resulting from metabolic disorders. Therefore, preventing, or at least decreasing the amount of these factors may have a positive impact on prevention or improvement of the metabolic problems. Recently, the herbal medicines are more considered due to more effectiveness. The application of synthetic antioxidants has been reduced recently due to their adverse effects on human health. The present research aims at evaluating the antioxidant power of chili pepper. Some solvents such as water, ethanol and water-ethanol solution, with or without ultrasound wave application, are used to provide the chili pepper extracts. The amount of tocopherol and phenol compounds in the extracts has been measured using stoichiometry method and the antioxidant power of the extracts was measured and analyzed by beta-carotene and DPPH tests. Finally, the extracts’ oxidative stability was determined. The data was statically analyzed by Analysis of Variance (ANOVA) and Duncan Multiple Range Test. The P level of <0.05 was considered statistically significant. The results showed that the amount of phenol compounds in terms of Gallic acid in different extracts are between 1066.3 and 1172.27 mg/kg, and the amount of tocopherol compounds in terms of alpha-tocopherol is between 693.52 and 867.65 mg/ml. the oxidative stability index in different extracts was between 5.55 and 7.23 hours. The inhibitory percentage of Linoleic acid oxidation in the extract varied between 57.2 and 83.6%, and the inhibitory percentage of DPPH radicals in different extracts varied between 71.33 and 91.87%. The maximum and minimum efficiency for phenol and tocopherol compound extraction were obtained using ethanol and water solvents, respectively. With a high antioxidant power, chili pepper can find a wide application in food, pharmaceutical, and cosmetic industries.

Utilization of unsaponifiable matter from rice bran oil fatty acid distillate for preparing an antioxidant-rich oleogel and evaluation of its properties

Rice bran oil fatty acid distillate (RBOFAD) is an important by-product obtained from the physical refining process. This fatty acid distillate contains high a amount of Unsaponifiable Matter (γ-oryzanol 3.27 gm/100gm UM; total tocopherol 10.93 mg/100 g UM; total phytosterol 21.81 g/100g UM; squalene 1.15 g/100 g UM and total fatty alcohol 73.34 g/100 g UM) and free fatty acids. Antioxidant-rich Oleogels were obtained from rice bran wax (RBW), rice bran oil fatty acid distillate (RBOFAD) and refined rice bran oil. The main objective of this study was to utilize the antioxidant-rich unsaponifiable matter of RBOFAD (UMRBOFAD) as an organogelator along with rice bran wax, which also acts as a good organogelator. Antioxidant-rich oleogel was prepared using UMRBFAD, ethylcellulose (EC) and RBW at 2%, 2%, 3% on weight basis, respectively, in refined rice bran oil and this antioxidant-rich oleogel was compared with rice bran oil oleogel using RBW at 7% on weight basis of rice bran oil. These oleogels were evaluated using a combination of techniques such as differential scanning calorimetry (DSC), polarized light microscopy (PLM), Viscosity, synchrotron radiation X-ray diffraction (SR-XRD) and FTIR Spectroscopy. The differential scanning calorimetry (DSC) measured the thermal properties of rice bran oil oleogel and high antioxidant-rich oleogel. Polarized light microscopy images revealed needle-like crystals for RBW. SR-XRD measurements were used for clarification of the crystal structures of the building blocks of these oleogels. The antioxidant activities of oleogels were evaluated involving DPPH and ABTS assays.

Exploiting the bioactive properties of γ-oryzanol from bran of different exotic rice varieties

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.

Suitability of stationary phase for LC analysis of biomolecules

Biologically active compounds such as carotenoids/isoprenoids, vitamins, steroids, saponins, sugars, long chain fatty acids, and amino acids play a very important role in coordinating functions in living organisms. Determination of those substances is indispensable in advanced biological sciences. Engineered stationary phase in LC for the analysis of biomolecules has become easier with the development of chromatographic science. In general, C₁₈ column is being used for routine analysis but specific columns are being used for specific molecule. Monolithic columns are found to have higher efficiency than normal column. Among recent introduction, triacontyl stationary phases, designed for the separation of carotenoid isomers, are widely used for the estimation of carotenoids. In comparison to conventional C₁₈ phases, C₃₀ phases exhibited superior shape selectivity for the separation of isomers of carotenoids. It is also found useful for better elution and analysis of tocopherols, vitamin K, sterols, and fatty acids. Vitamin K, E, and their isomers are also successfully resoluted and analyzed by using C₃₀ column. Amino bonded phase column is specifically used for better elution of sugars, whereas phenyl columns are suitable for the separation and analysis of curcuminoids and taxol. Like triacontyl stationary phase, pentafluorophenyl columns are also used for the separation and analysis of carotenoids. Similarly, HILIC column are best suited for sugar analysis. All the stationary phases are made possible to resolute and analyze the target biomolecules better, which are the future of liquid chromatography. The present article focuses on the differential interaction between stationary phase and target biomolecules. The applicability of these stationary phases are reported in different matrices.

Enzyme-assisted Aqueous Extraction of Oil from Rice Germ and its Physicochemical Properties and Antioxidant Activity

Enzyme-assisted aqueous extraction of rice germ oil (RGO) was performed in this study. The physicochemical properties, fatty acid composition, bioactive substances and antioxidant activity of RGO were analyzed. An enzyme composed of alcalase and cellulase (1:1, w/w) was found to be the most effective in the extraction yield of oil. The optimal oil yield of 22.27% was achieved under the conditions of an enzyme concentration of 2% (w/w), incubation time of 5 h, incubation temperature of 50°C, water to seed ratio of 5:1, and pH 6.0. The predominant fatty acids of RGO were oleic acid (39.60%), linoleic acid (34.20%) and palmitic acid (20.10%). The total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) composition of RGO were 22.50%, 39.60% and 36.00%, respectively. RGO yielded a high content of γ-oryzanol (530 mg/100 g oil), tocotrienol (62.96 mg/100 g oil), tocopherol (23.24 mg/100 g oil) and a significant amount of phytosterol (372.14 mg/100 g oil). It exhibited notable antioxidant activities with IC₅₀ values of 32.37 and 41.13 mg/mL, according to the DPPH radical scavenging assay and β-carotene/linoleic acid bleaching test, respectively.

Isolation of the unsaponifiable matter (squalene, phytosterols, tocopherols, γ-oryzanol and fatty alcohols) from a fatty acid distillate of rice bran oil

Rice bran oil is characterized by its unique composition of unsaponifiable matter such as oryzanol, squalene, sterols, tocopherols and fatty alcohols. Rice bran oil fatty acid distillate (RBOFAD) is an important by-product of physical refining plants. In the present study, an appropriate fractionation methodology is proposed for isolating the unsaponifiable matter into two fractions, squalene, phytosterols and fatty alcohols as fraction 1; tocopherols and γ- oryzanol as fraction 2. The two fractions together constitute the total unsaponifiable matter in the RBOFAD. The individual unsaponifiable matter components (γ-oryzanol 1.78g/100g, squalene 209.63 mg/100g, tocopherol 2.45mg/100g, total phytosterols 3.79g/100g and fatty alcohols 94.23g/100g) were isolated from RBOFAD by combining a chemical esterification process and liquid-liquid extraction process with 95% ethanol which extracted tocopherol, γ-oryzanol, sterols, squalene, FFA, monoglycerides; later with hexane extraction of the alkaline phase to remove squalene, sterols and fatty alcohols. The alkaline salts of tocopherols and γ-oryzanol are decomposed by the acidification and extraction of the unsaponifiable matter with n-hexane.

Some Strategies for Utilization of Rice Bran Functional Lipids and Phytochemicals

Rice bran contains a great amount of functional lipids and phytochemicals including γ-oryzanols, tocotrienols, and tocopherols. However, utilization of those compounds is limited and needs some proven guidelines for better implementation. We introduce some effective strategies for the utilization of rice functional lipids, including an introduction of pigmented rice varieties for better bioactive compounds, biofortification of rice tocotrienols, plasma technology for improving rice phytochemicals, supercritical CO₂ extraction of high quality rice bran oil, and an example on the development of tocotrienol-fortified foods.

Overexpression of HvHGGT Enhances Tocotrienol Levels and Antioxidant Activity in Barley

Vitamin E is a potent lipid-soluble antioxidant and essential nutrient for human health. Tocotrienols are the major form of vitamin E in seeds of most monocots. It has been known that homogentisate geranylgeranyl transferase (HGGT) catalyzes the committed step of tocotrienol biosynthesis. In the present study, we generated transgenic barley overexpressing HvHGGT under endogenous D-Hordein promoter (proHor). Overexpression of HvHGGT increased seed size and seed weight in transgenic barley. Notably, total tocotrienol content increased by 10-15% in seeds of transgenic lines, due to the increased levels of δ-, β-, and γ-tocotrienol, but not α-tocotrienol. Total tocopherol content decreased by 14-18% in transgenic lines, compared to wild type. The antioxidant activity of seeds was determined by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and lipid peroxidation assays. Compared to wild type, radical scavenging activity of seed extracts was enhanced by 17-18% in transgenic lines. Meanwhile, the lipid peroxidation level was decreased by about 20% in transgenic barley seeds. Taken together, overexpression of HvHGGT enhanced the tocotrienol levels and antioxidant capacity in barley seeds.

Physicochemical and Antioxidant Properties of Rice Bran Oils Produced from Colored Rice Using Different Extraction Methods

This study investigated the physicochemical and antioxidant properties of rice bran oil (RBO) produced from the bran of three rice varities; Khao Dawk Mali 105 (white rice), Red Jasmine rice (red rice) and Hom-nin rice (black rice) using three extraction methods including cold-press extraction (CPE), solvent extraction (SE) and supercritical CO₂ extraction (SC-CO₂). Yields, color, acid value (AV), free fatty acid (FFA), peroxide value (PV), iodine value (IV), total phenolic compound (TPC), γ-oryzanol, α-tocopherol and fatty acid profile were analyzed. It was found that the yields obtained from SE, SC-CO₂ and CPE extractions were 17.35-20.19%, 14.76-18.16% and 3.22-6.22%, respectively. The RBO from the bran of red and black rice samples exhibited high antioxidant activities. They also contained higher amount of γ-oryzanol and α-tocopherol than those of white rice sample. In terms of extraction methods, SC-CO₂ provided better qualities of RBO as evidenced by their physicochemical and antioxidant properties. This study found that RBO produced from the bran of black rice samples using SC-CO₂ extraction method showed the best physicochemical and antioxidant properties.

The Effects of Tocotrienol and Lovastatin Co-Supplementation on Bone Dynamic Histomorphometry and Bone Morphogenetic Protein-2 Expression in Rats with Estrogen Deficiency

Both tocotrienol and statins are suppressors of the mevalonate pathway. Supplementation of tocotrienol among statin users could potentially protect them against osteoporosis. This study aimed to compare the effects of tocotrienol and lovastatin co-supplementation with individual treatments on bone dynamic histomorphometric indices and bone morphogenetic protein-2 (BMP-2) gene expression in ovariectomized rats. Forty-eight female Sprague-Dawley rats were randomized equally into six groups. The baseline was sacrificed upon receipt. All other groups were ovariectomized, except for the sham group. The ovariectomized groups were administered orally daily with (1) lovastatin 11 mg/kg/day alone; (2) tocotrienol derived from annatto bean (annatto tocotrienol) 60 mg/kg/day alone; (3) lovastatin 11 mg/kg/day, and annatto tocotrienol 60 mg/kg/day. The sham and ovariectomized control groups were treated with equal volume of vehicle. After eight weeks of treatment, the rats were sacrificed. Their bones were harvested for bone dynamic histomorphometry and BMP-2 gene expression. Rats supplemented with annatto tocotrienol and lovastatin concurrently demonstrated significantly lower single-labeled surface, but increased double-labeled surface, mineralizing surface, mineral apposition rate and bone formation rate compared to individual treatments (p < 0.05). There was a parallel increase in BMP-2 gene expression in the rats receiving combined treatment (p < 0.05). The combination of annatto tocotrienol and lovastatin exerted either additively or synergistically on selected bone parameters. In conclusion, tocotrienol can augment the bone formation and mineralization in rats receiving low-dose statins. Supplementation of tocotrienol in statin users can potentially protect them from osteoporosis.

Deep sequencing transcriptional fingerprinting of rice kernels for dissecting grain quality traits

BACKGROUND

Rice represents one the most important foods all over the world. In Europe, Italy is the first rice producer and Italian production is driven by tradition and quality. All main rice grain quality traits, like cooking properties, texture, gelatinization temperature, chalkiness and yield, are related to the content and composition of starch and seed-storage proteins in the endosperm and to grain shape. In addition, a number of nutraceutical compounds and allergens are known to have a significant effect on grain quality determination. To investigate the genetic bases underlying the qualitative differences that characterize traditional Italian rice cultivars, a comparative RNA-Seq-based transcriptomic analysis of developing caryopsis was conducted at 14 days after flowering on six popular Italian varieties (Carnaroli, Arborio, Balilla, Vialone Nano, Gigante Vercelli and Volano) phenotypically differing for qualitative grain-related traits.

RESULTS

Co-regulation analyses of differentially expressed genes showing the same expression patterns in the six genotypes highlighted clusters of loci up or down-regulated in specific varieties, with respect to the others. Among them, we detected loci involved in cell wall biosynthesis, protein metabolism and redox homeostasis, classes of genes affecting in chalkiness determination. Moreover, loci encoding for seed-storage proteins, allergens or involved in the biosynthesis of specific nutraceutical compounds were also present and specifically regulated in the different clusters. A wider investigation of all the DEGs detected in pair-wise comparisons revealed transcriptional variation, among the six genotypes, for quality-related loci involved in starch biosynthesis (e.g. GBSSI, starch synthases and AGPase), genes encoding for transcription factors, additional seed storage proteins, allergens or belonging to additional nutraceutical compounds biosynthetic pathways and loci affecting grain size. Putative functional SNPs associated to amylose content in starch, gelatinization temperature and grain size were also identified.

CONCLUSIONS

The present work represents a more extended phenotypic characterization of a set of rice accessions that present a wider genetic variability than described nowadays in literature. The results provide the first transcriptional picture for several of the grain quality differences observed among the Italian rice varieties analyzed and reveal that each variety is characterized by the over-expression of a peculiar set of loci affecting grain appearance and quality. A list of candidates and SNPs affecting specific grain properties has been identified offering a starting point for further works aimed to characterize genes and molecular markers for breeding programs.

Effects of feeding outer bran fraction of rice on lipid accumulation and fecal excretion in rats

Outer bran fraction of rice (OBFR) contains higher concentrations of crude fiber, γ-oryzanol, and phytic acid compared to whole rice bran (WRB). In this study, we examined the effects of feeding OBFR on lipid accumulation and fecal excretion in rats. Twenty-one male rats at seven-week-old were divided into a control group and two treatment groups. The control group was fed a control diet, and the treatment groups were fed OBFR- or WRB-containing diet for 21 days. There was no significant difference in growth performance. Feeding OBFR diet increased fecal number and weight accompanied by increased fecal lipid content, while it did not affect mRNA expressions encoding lipid metabolism-related protein in liver. In addition, feeding OBFR-diet decreased the abdominal fat tissue weight and improved plasma lipid profiles, while WRB-containing diet did not affect them. These results suggested that feeding OBFR-diet might prevent lipid accumulation via enhancing fecal lipid excretion in rats.

Effect of different germination conditions on antioxidative properties and bioactive compounds of germinated brown rice

This study investigates antioxidative activity and bioactive compounds of ungerminated brown rice (UBR) and germinated brown rice (GBR). We used two rice cultivars (Oryza sativa L.), Taiwan Japonica 9 (TJ-9) and Taichung Indica 10 (TCI-10), as the materials in our experiments. The conditions for inducing germination are soaking time in water 24, 48, or 72 h; temperature 26 or 36°C; incubation in light or darkness; and open or closed vessels, in which the antioxidative activities and bioactive compounds of GBR were determined. We found that, in order to maximize antioxidative activity and bioactive compounds, germination should be under higher temperature (36°C), long soaking time (72 h), darkness, and closed vessel. GBR contains much higher levels of antioxidative activity and bioactive compounds than ungerminated brown rice (UBR). We found a strong correlation between antioxidative activities (DPPH radical scavenging ability, reducing power, and Trolox equivalent antioxidant capacity) and bioactive compounds (γ-oryzanols, tocopherol, and tocotrienol). Higher temperature (36°C) is also conducive to the production of GABA in GBR. These results are considered very useful research references for the development of future functional foods and additives.