Water Extract of Rice False Smut Balls Activates Nrf2/HO-1 and Apoptosis Pathways,Causing Liver Injury

Ustiloxins are vital cyclopeptide mycotoxins originally isolated from rice false smut balls that form in rice spikelets infected by the fungal pathogen Ustilaginoidea virens.The toxicity of the water extract of rice false smut balls(RBWE) remains to be investigated.Studies have shown that RBWE may be toxic to animals,but toxicological evidence is still lacking.In this study,we found that the IC50 values of RBWE to BNL CL.2 cells at 24 and 48 h were 40.02 and 30.11 μg/m L,respectively,with positive correlations with dose toxicity and time toxicity.After treatment with RBWE,the number of BNL CL.2 cells decreased significantly,and the morphology of BNL CL.2 cells showed atrophy and wall detachment.RBWE induced DNA presynthesis phase arrest of BNL CL.2 cells,increased the proportion of apoptotic cells and inhibited cell proliferation.RBWE up-regulated reactive oxygen species(ROS) levels and lowered mitochondrial membrane potentials.Additionally,Western blot and q RT-PCR results suggested that RBWE exerted the above effects by promoting the Nrf2/HO-1 and caspase-induced apoptosis pathways in vitro and in vivo.The contents of alanine aminotransferase,aspartate aminotransferase,alkaline phosphatase,and total bile acids in the serum of mice from Institute of Cancer were significantly up-regulated by RBWE.At the same time,RBWE can lead to increases in ROS and malondialdehyde contents,decreases in contents of oxidized glutathione,glutathione and reduced glutathione,as well as decrease in catalase and superoxide dismutase activities in mouse liver tissues,demonstrating that oxidative stress occurred in mice.Moreover,liver damage was further detected by haematoxylin-eosin staining and electron microscopy to verify the damage to the mice caused by RBWE.In general,RBWE may cause hepatotoxicity in vivo and in vitro via the apoptosis pathway,which provides a reference for hepatotoxicity and its mechanism of action.

Changes in Metabolites and Allelopathic Effects of Non-Pigmented and Black-Pigmented Lowland Indica Rice Varieties in Phosphorus Deficiency

Phosphorus(P) levels alter the allelopathic activity of rice seedlings against lettuce seeds. In this study, we investigated the effect of P deficiency on the allelopathic potential of non-pigmented and pigmented rice varieties. Rice seedlings of the white variety Khao Dawk Mali(KDML105, non-pigmented) and the black varieties Jao Hom Nin(JHN, pigmented) and Riceberry(RB, pigmented) were cultivated under high P(HP) and low P(LP) conditions. Morphological and metabolic responses to P deficiency were investigated. P deficiency inhibited shoot growth but promoted root growth of rice seedlings in all three varieties. Moreover, P deficiency led to decreased cytosolic phosphate(Pi) and total P concentrations in both shoot and root tissues. The subsequent reduction in internal P concentration enhanced the accumulation of phenolic compounds in both shoot and root tissues of the seedlings. Subsequently, allelopathy-based inter-and intra-specific interactions were assessed using water extracts from seedlings of the three varieties grown under HP and LP conditions. These extracts were tested on seeds of lettuce, the weed Dactyloctenium aegyptium, and the same rice variety. The shoot and root extracts from P-deficient seedlings reduced the germination of all recipient plants. Specifically, the shoot extract from P-deficient KDML105 seedlings reduced the germination index(GI) of lettuce seeds to 1%, while those from P-deficient RB and JHN seedlings produced GIs of 32% and 42%, respectively. However, when rice seeds were exposed to their own LP shoot and root extracts, their GIs increased up to 4-fold, compared with the HP extracts. Additionally, the shoot extracts from P-deficient plants also stimulated the germination of D. aegyptium by about 2–3-fold, whereas the root extracts did not have this effect. Therefore, P starvation led to the accumulation and exudation of phenolics in the shoots and roots of rice seedlings, altering their allelopathic activities. To adapt to P deficiency, rice seedlings potentially release signaling chemicals to suppress nearby competing species while simultaneously promoting their own germination and growth.

Efficacy of Selected Plant Extracts against <i>Pyricularia grisea</i>, Causal Agent of Rice Blast Disease

Rice blast disease, caused by a seed-borne fungus Pyricularia grisea, is an important and serious disease of rice (Oryza sativa L.) worldwide. The disease has been reported to cause yield losses of up to 40% in Tanzania. Studies were conducted to determine the effect of aqueous extracts of Aloe vera, Allium sativum, Annona muricata, Azadirachta indica, Bidens pilosa, Camellia sinensis, Chrysanthemum coccineum, processed Coffee arabica, Datura stramonium, Nicotiana tabacum and Zingiber officinalis for control of rice blast disease (Pyricularia grisea) in-vitro and in-vivo. The results indicate that processed C. arabica at 10% and 25% (v/v) had the highest (81.12%) and (89.40%) inhibitory effect, respectively, against P. grisea. Aqueous extract from N. tabacum at 10% concentration ranked third (80.35%) in inhibiting P. grisea. These were followed by extracts from 25% A. vera (79.45%) and 25% C. coccineum flower (78.83%). The results also indicate that, extracts from A. indica, A. vera, A. sativum, C. arabica, D. stramonium, C. sinensis, Z. officinalis and N. tabacum did not have any phytotoxic effect on seed germination, shoot height, root length, dry weight, seedling growth and seedling vigour index. These plant extracts can thus be used for rice seed treatment to manage rice blast disease.

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.

Repellent Activity of Extracts of Wild Rice Species against Panonychus citri and Aphis citricola in Associated with Esterase Isoenzyme in Insests

Six species of wild rice with different ecophenotypes including Oryza grandiglumis （E6-1, E6-3 / 6-4）, O. minuta （E13-9, E13-13）, O. officinalis（E15-8, E15-13）, O. punctata （E16-1, E16-3, E16-13）, O. granulata（E7-4）, and O. latifolia（101392, E9-1, E9-10） were extracted with methnol and the repellent activity of the extracts against the two insects Aphis citricola and Panonychus citri were studied. The extracts of O. officinalis E15-8 showed higher repellent rate to the two insects than those of the other species. The repellent rates of the extracts of E15-8 to P. citriand A. citricola were 83.26% and 87.86% at 5×10^4 μg/mL in 24 h and 87.95% and 82.43% in 48 h, respectively. The extracts of O. officinalis E15-8 had the effect of inhibition to the esterase of the two insects.

A Simple,Efficient and Rapid Method for Good Quality DNA Extraction from Rice Grains

An efficient and good DNA extraction protocol should be simple, affordable and yield enough DNA with high quality. Rice(Oryza sativa L.) DNA extraction methods often use seedlings or leaves rather than the grains and tend to be time-consuming, involve multiple steps, and use hazardous chemicals and expensive enzymes. Rice grains offer several benefits over seedlings and leaves as a source of DNA for genetic analysis. However, these benefits are underutilized because the bulk of a rice grain is made up of starch. It is particularly important, but difficult to get rid of the starch while extracting DNA from rice grains. This co-precipitated polysaccharide is a known inhibitor of DNA polymerase activity in polymerase chain reaction(PCR). We describe here a very simple and highly affordable Chelex~?-100 based DNA extraction method from rice grains. It does not require any hazardous chemicals or enzymes. This method reproducibly extracts DNA with good purity indices(A_(260)/A_(230) and A_(260)/A_(280) values), but requires only a few steps.

Effects of Rice Straw Silicification and Characters of Extraction Biogenic Silicon on the Degradation of Fibrous Components in Rice Straw

Straw of seven rice varieties with early-, middle- and late maturity was collected from Huazhong Agricultural University in Hubei. A study was carried out for rice straw in the aspects of the characters of straw silicification and extraction biogenic silica (EBSi), the relationship between characters of EBSi and kinetic characteristics of degradation of fibrous components in fistulated cows, as well as the effect of urea treatment on rice straw desilicification. Although total silica content (ADISi) in rice straw was similar, the efficiency of extraction biogenic silica (EEBSi) and cellulose in early varieties were significantly higher than those in middle (18.9% and 9.1 %) and late ones (26.1% and 11.2%). The degradability of EBSi and cellulose of early varieties were higher than those of middle by 70.0% and 17.5%, and of late varieties by 47.8% and 23.7% , respectively. The in sacco degradability and in vitro VFA production of early varieties were also higher than those of middle by 14.5% and 19.0%, and late by 12.9% and 14.8%. Comparing the morphological fractions of the rice straws, EEBSi, cellulose content, and in vitro VFA production were different with the order of blade < sheath < stem. A significant correlation was found between the contents of EBSi and cellulose (r= 0.86), and the two contents were remarkably correlated with the potential straw degradability (a + b) by r = 0.90 and 0.84 respectively. Therefore, EBSi in rice straw was a main factor affecting the potential degradability of rice straw, rather than the ADISi of straw. Urea treatment improved rice straw degradability, degradation rate and potential degradability by 10.8% , 27.9% , and 10.1% respectively, compared to untreated straws.

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.

Study on Extraction Method of Selenium-enriched Rice

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

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·.

Iksan526 Rice Callus Extract Induces Dedifferentiation of Rabbit Articular Chondrocytes via ERK1/2 and PI-3K/Akt Pathways

The resveratrol-enriched transgenic rice line Iksan526(IS526),first developed by the Rural Development Administration of Korea using genetic engineering techniques,shows beneficial health effects in mitigating metabolic syndrome and obesity.However,the effects of IS526 on the differentiation of chondrocytes and the underlying mechanism have not been investigated in detail.In this study,the effects and cellular regulatory mechanisms of IS526 on rabbit articular chondrocytes were examined.Following IS526 callus extract treatment,the expression levels of differentiation-related proteins were detected via western blotting,Alcian blue staining and immune-luorescence staining.IS526 decreased the type Ⅱ collagen and proteoglycan levels in dose-and time-dependent manners.We further analyzed the effects of IS526 on skeleton genesis in zebrafish larvae using Alcian blue staining,which showed a reduction in cartilage formation along with increased production of matrix metalloproteinase(MMP)-13.IS526 also increased the phosphorylation of ERK1/2 and p38 kinase but inhibited the phosphorylation of Akt.Pharmacological inhibition of MMP-13 blocked the IS526-induced decrease in type Ⅱ collagen levels.Inhibition of p38 kinase or PI-3K/Akt with SB203580 and LY294002 enhanced the suppression of type Ⅱ collagen,but the blockage of ERK-1/2 by PD98059 rescued IS526-induced dedifferentiation.These results suggested that IS526 regulates type Ⅱ collagen and MMP-13 expression via the ERK1/2 and PI-3K/Akt pathways in rabbit articular chondrocytes.

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.

Comparison of four methods of DNA extraction from rice

Polyphenols,teroens,and resinsmake it difficult to obtain high qualitygenomic DNA from rice.Four ex-traction methods were compared inour study,and CTAB precipitationwas the most practical one.Materials used were old leavesfrom Ftransgenic rice in Hainan andfresh leaves from Ftransgenic rice inKunming.Procedures of the four methodswere as follows:1.Basical method:powder 1 gold or new leaves→added 2 ml ex-traction solution(100 mmol/L

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.

基于YOLOv5m和CBAM-CPN的单分蘖水稻表型参数提取

为快速获取单分蘖水稻植株的形态结构和表型参数,该研究提出了一种基于目标检测和关键点检测模型相结合的骨架提取和表型参数获取方法。该方法基于目标检测模型生成穗、茎秆、叶片的边界框和类别,将所得数据分别输入到关键点检测模型检测各部位关键点,按照语义信息依次连接关键点形成植株骨架,依据关键点坐标计算穗长度、茎秆长度、叶片长度、叶片-茎秆夹角4种表型参数。首先,构建单分蘖水稻的关键点检测和目标检测数据集;其次,训练Faster R-CNN、YOLOv3、YOLOv5s、YOLOv5m目标检测模型,经过对比,YOLOv5m的检测效果最好,平均精度均值(mean average precision,mAP)达到91.17%;然后,应用人体姿态估计的级联金字塔网络(cascaded pyramid network,CPN)提取植株骨架,并引入注意力机制CBAM(convolutional block attention module)进行改进,与沙漏网络(hourglass networks,HN)、堆叠沙漏网络模型(stacked hourglass networks,SHN)和CPN模型相比,CBAM-CPN模型的预测准确率分别提高了9.68、8.83和1.06个百分点,达到94.75%,4种表型参数的均方根误差分别为1.06 cm、0.81 cm、1.25 cm和2.94°。最后,结合YOLOv5m和CBAM-CPN进行预测,4种表型参数的均方根误差分别为1.48、1.05、1.74cm和2.39°,与SHN模型相比,误差分别减小1.65 cm、3.43 cm、2.65 cm和4.75°,生成的骨架基本能够拟合单分蘖水稻植株的形态结构。所提方法可以提高单分蘖水稻植株的关键点检测准确率,更准确地获取植株骨架和表型参数,有助于加快水稻的育种和改良。

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。

菌肥及泥炭土浸提液对植物提取土壤Cd的影响

采用温室盆栽试验,研究菌肥和泥炭土浸提液对东南景天生物量、Cd富集特征、土壤Cd有效性和土壤理化性质及对后茬水稻在落干条件下水稻Cd的影响。结果表明,菌肥和泥炭土浸提液均能提高东南景天对土壤重金属的提取效率,其中施用两次液体菌肥的效果最好,东南景天对Cd提取量为0.34 mg·pot^(-1),是对照的3.1倍,泥炭土浸提液处理的东南景天Cd提取量为0.32 mg·pot^(-1),是对照的2.9倍,这两种处理对Cd的提取率较高,达到13%~15%,土壤全量Cd的降低幅度达到17.55%~20.41%。东南景天收获后种植水稻,落干条件下促进了水稻对Cd的吸收,稻米和茎叶的Cd提取量较对照增幅分别为30.31%~396.24%和12.36%~257.65%,其中在菌肥及泥炭土浸提液联合处理下水稻对Cd的吸收最大,稻米和茎叶的Cd含量分别为2.14 mg·kg^(-1)和2.88 mg·kg^(-1),水稻地上部对Cd总提取率达到3.15%。因此,施用两次菌肥是提高东南景天提取土壤Cd的有效措施,菌肥与泥炭土浸提液联合施用在落干条件下显著强化了水稻对土壤Cd的提取。

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。

稻谷壳提取物对钢在HCl中的缓蚀作用

以稻谷壳为原料,用超声辅助提取法制备出稻谷壳提取物(RHE),探究了其在1.0 mol·L^(-1)HCl中对钢的缓蚀作用。结果表明,RHE对钢在1.0 mol·L^(-1)HCl中有较好的缓蚀效果,缓蚀效果随RHE浓度的增加而增强,且30℃、RHE浓度为250 mg·L^(-1)时,缓蚀率达到92.86%。同时,RHE具有一定的长期稳定性。RHE的吸附行为符合Langmuir吸附等温式,其标准吸附Gibbs自由能(ΔG^(0))为-20~-40 kJ·mol^(-1),表明RHE的吸附方式为混合吸附。极化曲线测试表明RHE为混合型缓蚀剂,同时抑制阴极和阳极的腐蚀反应,电化学阻抗谱测试(EIS)表明钢在1.0 mol·L^(-1)HCl的腐蚀受电荷转移电阻的控制。溶液的紫外-可见吸收光谱(UVvis)和表面张力证实RHE吸附到钢的表面导致RHE浓度减少。RHE的加入导致钢表面接触角增大,疏水性增强,证实了缓蚀保护膜的形成。扫描电子显微镜(SEM)和金相显微镜进一步证实RHE在钢表面形成缓蚀保护膜。此外,FTIR表明RHE分子中含有O、N等杂原子,再次证实了RHE混合吸附到钢表面形成缓蚀保护膜。