Optimization of Extraction Technology for Rice Bran Oil

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

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

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

A comprehensive review on anti-diabetic property of rice bran

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

Reactive oxygen species and senescence modulatory effects of rice bran extract on 4T1 and NIH-3T3 cells co-treatment with doxorubicin

Objective:To determine the effect of rice bran extract(RBE)in combination with doxorubicin on 4 T1 triple-negative breast cancer cells and NIH-3 T3 cells.Methods:RBE was obtained by maceration with n-hexane.The phytochemical profile of RBE was observed using highperformance liquid chromatography.Cytotoxic effect of RBE was evaluated through MTT assay.In addition,flow cytometry was used for cell cycle and apoptosis analysis.Cellular senescence was observed using SA-β-Gal assay and intracellular reactive oxygen species(ROS)levels were evaluated using DCFDA staining.The pro-oxidant property of RBE was also evaluated through 1-chloro-2,4-dinitrobenzene spectrophotometry and molecular docking.Results:RBE was obtained with a yield of 18.42%w/w and contained tocotrienols as the major compound.RBE exerted no cytotoxic effect on 4 T1 and NIH-3 T3 cells.However,RBE in combination with doxorubicin decreased 4 T1 cell viability synergistically(combination index<0.9)and induced apoptosis and senescence on 4 T1 cells.RBE significantly decreased senescence in doxorubicin-treated NIH-3 T3 cells.Additionally,RBE did not increase ROS levels in doxorubicin-treated 4 T1 cells.Meanwhile,the combination of RBE and doxorubicin reduced ROS levels in NIH-3 T3 cells.RBE significantly reduced glutathione-S-transferase activity and alpha-tocotrienol interacted with glutathione-Stransferase in the glutathione binding site.Conclusions:Rice bran may be used as a co-chemotherapeutic agent to improve the therapeutic effectiveness of doxorubicin while protecting against the cellular senescence effects of doxorubicin on healthy cells.

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

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

Pilot Scale Mill Characterization and Evaluation of Rice Bran Oil Concentration of Jazzman Rice

The demand for aromatic rice has increased in the United States during the last two decades. Jazzman, the first US-bred jasmine-type rice variety, was released by the Louisiana State University (LSU) AgCenter Rice Research Station in 2008 to compete for a market share of jasmine-type rice. Jazzman, a long grain aromatic rice variety, was developed from a cross between Ahrent and an unreleased aromatic Chinese rice line 96a-8. In pre-release field tests and laboratory scale evaluation, Jazzman rice yield and milling quality compared favorably with two high-yielding and good-milling non-aromatic long grain varieties, Cypress and Cheniere. Pilot scale evaluation of Jazzman for milling quality supported laboratory scale evaluation while providing additional data for milling optimization. Pilot scale milling uses larger rice samples than laboratory scale testing and employs a continuous process instead of the batch process used at laboratory scale. As a result, pilot scale milling offers more comprehensive information regarding the milling yield and quality of rice varieties as they are considered for industrial scale release. Another consideration for new rice varieties involves their potential for value-added processing, in which waste streams during processing can be used to create valuable products. The oil from rice bran is one such product. The objective of this study was to use pilot scale milling to determine the potential of Jazzman for industrial scale release, including its potential for value-added processing. Results showed that bran was easily removed during milling;the head rice recovery ranged from 66% to 74% as a function of milling flow rate. Water polishing had little effect on head rice recovery, but improved the final degree of milling (DOM) to a commercially acceptable level of 87 - 90. Additionally, rice bran oil concentration decreased as pilot scale flow rate increased, indicating that oil was concentrated in the outer bran layer of Jazzman. Pilot scale milling shows that Jazzman is a high-yielding and good-milling aromatic long grain rice variety.

Oxidative Stability of Green Tea Extract-Enriched Rice Bran Oil During Storage

Adding green tea extract to rice bran oil was expected to improve its oxidative stability,so this study was conducted to investigate oxidative stability of green tea extract-enriched rice bran oil(RBOG) during storage at 60℃ for 15 days compared to rice bran oil(RBO),olive(OL),canola(CN),and grape-seed oil(GS).Acid values did not increase during storage,and the highest value was found for OL.The peroxide values of RBOG,RBO,CN,OL,and GS increased for up to 15 days.The highest average rate constant for the change in peroxide value was found for RBO(0.282).TBARS increased continually during storage of RBOG,RBO,CN,and OL;however,the value increased for up to 9 days and then decreased for GS.The highest average rate constant of change in TBARS was found for CN.Overall,the results suggest that green tea extract improves oxidative stability of rice bran oil.

红米米糠非淀粉多糖的提取纯化与结构表征

红米是我国产量最大的有色米,具有抗氧化、抗炎等功能,但其水溶性多糖资源并未被开发利用。该文以红米米糠为原料,脱脂后利用热水提取,经脱色、除蛋白、醇沉、透析制得红米米糠非淀粉多糖(non-starch polysaccharides from red rice bran,RRBP)。利用DEAE-52 Cellulose和Sephadex G-200分离纯化得到不同的部分,其中比例最大的为RRBP4组分。通过高效液相色谱、傅里叶红外光谱与完全酸水解、部分酸水解、β-消除、I 2-KI实验、刚果红实验等方法对RRBP4的分子质量、单糖组成、主链与侧链、糖苷键、分支程度与三螺旋构象进行分析。结果表明,RRBP4的相对分子质量为1.65×10^(5)Da,由甘露糖、核糖、鼠李糖、葡萄糖醛酸、半乳糖醛酸、葡萄糖、半乳糖、木糖和阿拉伯糖组成,其摩尔比例为0.29∶1.93∶0.35∶1.41∶0.50∶1.00∶5.58∶1.67∶2.56,是一种以半乳糖为主的酸性杂聚糖。RRBP4中有62.40%的多糖集中于侧链,是一种高度支化的多糖。RRBP4是以α-糖苷键为主且含有氨基酸的多糖,同时具有三螺旋结构。红米米糠非淀粉多糖的结构分析能够为开发其在食品工业中的应用提供科学基础数据。

米糠酚类物质对高脂诱导的小鼠糖代谢异常及氧化应激的改善作用

目的:研究不同剂量的米糠酚类物质(RBPE)对高脂诱导的小鼠糖代谢及氧化应激水平的影响,为揭示米糠改善糖代谢作用提供理论依据。方法:选用6周龄的C57BL/6J小鼠适应性饲养1周后,随机分为4组,包括正常组、高脂组、RBPE低剂量组(200 mg/kg,HF+LP组)和高剂量组(400 mg/kg,HF+HP组),实验共16周,测定脏器指数、脂肪细胞形态、糖代谢指标和氧化应激相关指标。结果:RBPE可以剂量依赖地降低小鼠肝脏、附睾脂肪和肾周脂肪的脏体比,降低高脂小鼠空腹血糖水平,改善高脂引起的糖耐量受损(P<0.05):与高脂组相比,HF+LP、HF+HP组小鼠肝脏的脏体比分别降低15.75%和39.61%,附睾脂肪的脏体比分别降低23.03%和39.83%,肾周脂肪的脏体比分别降低43.68%和56.83%,空腹血糖水平分别降低14.06%和20.21%,糖耐量曲线下面积分别降低19.06%和23.81%。进一步研究显示,低、高剂量的RBPE可显著降低高脂小鼠血清和肝脏组织MDA的含量并提高SOD活力,与高脂组相比,HF+HP组小鼠血清和肝脏MDA含量分别降低了48.93%和38.68%,SOD活力分别提高了80.44%和67.05%;并提高了高脂诱导小鼠肝脏过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-px)等抗氧化酶的活力及抗氧化物谷胱甘肽(GSH)的含量(P<0.05),与高脂组相比,HF+HP组小鼠肝脏CAT、GSH-px活力及GSH含量分别提高了48.49%,31.67%,123.90%。结论:米糠酚类物质可以改善高脂诱导的小鼠糖代谢紊乱,其机制可能与改善机体氧化应激反应有关。

米糠提取物在食品及健康领域中的应用研究进展

米糠提取物(rice bran extract,RBE)是从米糠中分离得到的营养物质,由于其含有大量的生物活性成分,具有良好的抗氧化能力,在食品及健康领域能发挥独特优势。此外,所用的米糠原料和制备方法不同,所得到的生物活性化合物的种类和含量不同。本文结合近年来RBE的相关研究,系统论述其常用制备方法、功能特性及应用现状,并提出目前研究所存在的不足,旨在探讨其在食品及健康领域中的潜在应用价值及未来研究热点,以期为米糠精深加工提供参考。

提取方法对米糠纤维素理化性质的影响

以脱脂米糠为原料提取米糠不溶性膳食纤维(IDF),采用氢氧化钠-亚氯酸钠法、超声辅助氢氧化钠-亚氯酸钠法、氢氧化钠-过氧化氢法、超声辅助氢氧化钠-过氧化氢法等四种方法提取米糠纤维素,并比较4种提取方法对米糠纤维素结构特性和功能特性的影响。结果表明,超声辅助氢氧化钠-亚氯酸钠法提取纤维素具有最高纯度(88.69%)和结晶度(59.30%),且有较好热稳定性、持水性、持油性和葡萄糖吸附能力。与氢氧化钠-亚氯酸钠法相比,氢氧化钠-过氧化氢法提取的纤维素的平均粒径小,持水性和持油能力弱,而胆酸盐吸附能力和淀粉酶抑制活性更强。FT-IR图谱表明氢氧化钠-过氧化氢法提取的纤维素中含有一定量的木质素和半纤维素。SEM分析表明氢氧化钠-亚氯酸钠法提取的米糠纤维素表面更加光滑,超声辅助处理可以显著提高了纤维素的纯度以及持水性和持油性,但对纤维素的平均粒径、热稳定性无显著影响。

米糠制粒浸出工艺的研究与实践

旨在验证改进型糠粞分离器的分离效果和为米糠制粒浸出工艺提供一定的技术参考,采用风选分离糠粞、制粒烘干、平转浸出、负压蒸发、DTDC湿粕脱溶的米糠制粒浸出工艺制取米糠原油,通过总结生产中的一些问题和操作经验,改进了风选式糠粞分离器,确定了颗粒化处理方式及米糠制粒浸出工艺关键点的参数。结果表明:采用改进的糠粞分离器,糠粞分离效果良好,处理量大;以低温制粒烘干代替膨化进行米糠的颗粒化处理,米糠制粒浸出工艺关键点的工艺参数为制粒温度60℃,颗粒直径3.7 mm,烘干机出料温度60℃,烘干后颗粒水分5%,浸出温度55℃,蒸发系统真空度70 kPa,第一蒸发器出油浓度85%、温度65℃,第二蒸发器出油浓度95%、温度98℃,汽提塔出油温度102℃,蒸脱机气相温度76℃。采用优化的米糠制粒浸出工艺可改善米糠原油及糠粕品质,并可降低能耗。

米糠蛋白的提取、特性、功能复合物及应用研究进展

米糠作为稻谷加工的主要副产物,富含油脂、蛋白质及生物活性物质等诸多营养成分。米糠中蛋白质含量约占米糠的15%~17%,分为清蛋白、球蛋白、醇溶性蛋白和谷蛋白,其氨基酸组成接近FAO/WHO推荐的模式,致敏性低,生物效价高,是一种优质的植物蛋白资源。米糠蛋白的获取能够提高稻谷的附加值,在食品、医药领域有着广阔的应用前景。因此,本文综述了米糠蛋白的提取方法、功能特性及功能复合物,介绍了米糠蛋白及其复合物在生物活性肽、婴幼儿食品、食品添加剂、营养递送体系等领域的应用现状,最后提出了未来米糠蛋白的研究挑战,为米糠蛋白的工业化生产及高值利用提供一定的思路和参考。

米糠中抗氧化肽的高压均质-酶法制备及鉴定

以3种粳稻和3种籼稻米糠为原料,通过高压均质-酶法制备米糠多肽,对酶解液中的多肽进行分离纯化及结构鉴定,探究其抗氧化机制。以肽含量和还原力为指标,最佳提取工艺为均质压力60 MPa、料液比1∶15(g∶mL)、酶添加量3200 U/g、酶解时间2 h、pH 10、温度55℃。筛选出抗氧化活性最高的蛋白酶解液进行超滤、葡聚糖凝胶Sephadex G-25分离纯化和LC-MS/MS鉴定后,得到60条具有潜在活性的肽。分子对接结果表明,多肽YGGGY的结合自由能最低,在CD38蛋白(NAD+降解酶)的活性位点通过氢键、范德华力、盐桥等产生相互作用,暗示着其具有潜在抑制NAD+降解酶活性的功能,从而使机体能够保持足够的NAD+含量以应对氧化应激损伤,延缓机体衰老。该研究为分析、解释米糠肽的分子机制提供了科学理论依据,也为全谷物产品的开发提供依据。

浅析米糠油的制备、健康功效及发展趋势

米糠油因其独特的饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸比例,以及酚类化合物和谷维素等功能性成分,始终是当前研究的重点。传统索氏提取法制备的米糠油具有溶剂残留、效率低、不利于环保等缺点。近年来,新型热联合提取技术(如微波辅助、超声辅助、超临界流体、酶辅助和亚临界等)等新方法的发展,已被证实可以显著提高米糠油的产量和质量。此外,米糠油具有抗氧化、抗炎、降血糖、降血脂等功效,为米糠油的应用和发展奠定了基础。本综述提供了有关米糠油的制备、健康功效以及未来发展趋势的全面信息,旨在为米糠油的开发利用提供一定的借鉴参考。

米糠蛋白的提取及其应用研究进展

米糠是稻米加工的主要副产物,米糠中含有12%~18%的蛋白质,米糠蛋白具有极高的营养价值和多种生物活性,在食品、药品等领域表现出极大的应用潜力,是一种优质的植物蛋白资源。综述了米糠蛋白的提取方法及其在食品工业上的应用研究进展,为实现米糠蛋白的广泛应用、提高米糠的附加值提供一定参考。

海红米糠多糖的提取工艺、结构表征及抑制HepG2细胞增殖研究

该文主要考察了海红米糠多糖(sea red rice bran polysaccharide,SRBP)的提取工艺、结构表征及其抑制HepG2细胞增殖的情况。以海红米皮糠为原料,考察了不同提取方法对SRBP得率的影响。在单因素的基础上采用响应面法优化了SRBP的最佳提取工艺。采用苯酚硫酸法和间羟基联苯比色法测定其化学组成,液相色谱法测定分子质量及单糖组成,并用紫外、红外光谱、扫描电镜对其进行结构表征。采用噻唑蓝(methyl thiazolye tetrazolium,MTT)法测定SRBP对HepG2细胞生长的影响。实验结果表明,SRBP的最佳提取工艺条件为酶解时间61 min,料液比(g∶mL)1∶33,酶解温度59℃。经测定,SRBP是一种纯度较高的甘露糖吡喃型杂多糖,不含蛋白及核酸物质,表面粗糙、呈片状结构。MTT实验表明,SRBP在800μg/mL下对HepG2细胞作用24 h的存活率仅为(9.77±0.81)%,表明其具有抑制HepG2增殖的能力。综上可知,提取得到的SRBP具有一定的抗肿瘤活性,为其在饮食干预肝癌等方面提供了理论依据和数据参考。

超声-微波协同提取富硒米糠蛋白的工艺优化及其抗氧化活性评价

为解决富硒米糠蛋白提取率低、提取时间长及提取后功能特性下降等问题,以脱脂富硒米糠粉为原料,通过单因素试验和正交试验对超声-微波协同提取富硒米糠蛋白的工艺进行优化,通过与超声辅助法、微波辅助法和碱提法比较,探究该提取方法对富硒米糠蛋白的提取效果、抗氧化活性以及提取后米糠颗粒表面形貌变化的影响。结果表明,超声-微波协同提取富硒米糠蛋白的最佳工艺条件为超声功率600 W、微波功率500 W、提取时间20 min、料液比1∶40,在此条件下富硒米糠蛋白的提取率为86.94%,与超声辅助法、微波辅助法、碱提法相比富硒米糠蛋白提取率分别提高了40.96%、48.00%、53.50%,并且提取的富硒米糠蛋白抗氧化能力和硒含量更高。扫描电镜结果显示,超声-微波协同提取后米糠颗粒表面疏松卷曲,完整皮层结构消失,说明超声-微波协同能通过强烈破坏米糠颗粒结构增加富硒米糠蛋白的提取率,并提高其抗氧化活性。综上,超声-微波协同提取技术能够促进富硒米糠蛋白的提取并提高其抗氧化活性。

天然低共熔溶剂提取米糠酯酶工艺优化及其纯化与酶学性质研究

目的:采用天然低共熔溶剂(Natural deep eutectic solvents,NADES)提取米糠酯酶并优化提取工艺参数,纯化米糠酯酶获得高纯度米糠酯酶,并探究其酶学特性。方法:合成了10种不同的NADES、选用了水浴搅拌和超声两种处理方式进行筛选,然后对提取效果最佳的NADES和方法进行单因素和响应面优化,参数包括料液比、含水量、提取温度和提取时间;将最优提取工艺得到的粗酶液通过阴离子交换树脂DEAE纯化,然后进行酶学性质的探究。结果:最佳提取米糠酯酶的工艺为在含有5%水分的脯氨酸-甘油(摩尔比1:2)溶剂体系中,水浴搅拌3.0 h,温度74.0℃,米糠和溶剂料液比为9:30,此时米糠酯酶活力为2.96 U。通过阴离子交换树脂DEAE纯化,获得了纯度较高的米糠酯酶,纯化倍数为1.74倍,回收率为69.40%,分子量约为35 kDa,对硝基苯酚乙酯为最适底物,最适温度和pH分别是40.0℃、pH8.0,在30.0~40.0℃和pH7.0~9.0时米糠酯酶均保持良好的稳定性。氯化胆碱-甘油、脯氨酸-甘油两种NADES对米糠酯酶的活力有较好的维持作用。结论:天然低共熔溶剂提取方式是一种简单、绿色的提取方式,可为生物活性化合物的绿色提取研究提供一些参考。

酶法辅助提取、纯化米糠蛋白工艺优化

旨在为米糠副产品的精深加工利用提供指导,利用碱性蛋白酶辅助碱溶酸沉法提取米糠蛋白,并进一步以纤维素酶纯化米糠蛋白,在单因素实验的基础上通过正交实验优化提取、纯化工艺条件。结果表明:米糠蛋白提取的最佳工艺条件为酶解pH 10.5、酶解温度50℃、料液比1∶10、酶解时间120 min、加酶量2.5%,在此条件下米糠蛋白提取率为75.2%;米糠蛋白纯化的最佳工艺条件为酶解温度50℃、酶解pH 5.0、酶解时间60 min、加酶量4%、料液比1∶10,在此条件下米糠蛋白纯度为81.6%,提取率为72.6%。采用此方法可以得到提取率和纯度均较高的米糠蛋白。