二乙氨乙基交联葡聚糖和季氨基琼脂糖色谱分离植物脂多糖的比较

比较了应用Q Sepharose Fast Flow凝胶和DEAE-Sephadex A50凝胶柱色谱分离米糠提取物中米糠脂多糖(LPSR)的效果。结果表明：通过改变体系的离子强度，两凝胶都可使LPSR与一般多糖分离，但仅Q Sepharose Fast Flow柱色谱可实现LPSR与米糠色素的有效分离，并获得淡黄色、99．5％纯度的LPSR产品，而且耐盐性能好于DEAE-Sephadex A50。     

从米糠中制取植酸的工艺研究现状及其进展

植酸是一种重要的精细化工产品,在许多领域有广泛的用途。文章对近几年来从米糠中制取植酸的工艺研究的现状和进展进行了综述,以期待更好地开发和利用植酸。     

米糠中阿魏酸的提取及荧光分光光度法检测

确定了新鲜米糠中阿魏酸的最佳提取工艺。用高效液相色谱法对提取产品作定性检测,用荧光分光光度法对提取产品作定量检测。阿魏酸在0.2~2.2μg/mL浓度范围内呈良好的线性关系,相关系数为0.99958,平均回收率为99.0%。此法具有准确、简便、快速、灵敏等优点。     

微生物发酵米糠制备神经酰胺

用CO2激光辐射筛选培育出高产鞘磷脂酶的工程菌——雅致放射毛霉变异株AE255-6。AE255-6固体发酵产鞘磷脂酶的优化条件经试验确定为采用变温培养,培养时间共72h,前24h培养温度30℃,后48h培养温度25℃,培养基pH 7.0—8.0,培养基含水量65%,接种量12%。以米糠为原料,采用AE255-6固体发酵产生鞘磷脂酶以定向水解鞘磷脂产生游离神经酰胺,使米糠中游离神经酰胺含量从0.022%提高到0.064%。将CO2超临界萃取技术与D140大孔树脂纯化相结合,获得纯度为99.2%的神经酰胺产品。产品纯度与美国S igm a公司的相当,且经检测证明其安全性好。     

植物脂多糖的离子交换色谱

研究了应用ＤＥＡＥ－Ｓｅｐｈａｄｅｘ Ａ５０分离米糠提取物中植物脂多糖的方法。结果表明，通过改变体系的离子强度，采用静态吸附和柱色谱都能有效分离脂多糖与一般多糖，柱色谱有脂多糖纯度和吸附效率分别为９８．７％和８８．０％，静态吸附则为９０．５％帮７７．９％。     

分光光度法测定稻米及副产品中矿物元素锗

采用分光光度法对稻米及副产品中矿物元素锗进行分析研究。在优化实验条件下,标准曲线回归方程为A=0.012 36C+0.030 39,相关系数r=0.999 6,线性范围为0~7.2μg/mL,方法加标回收率为98.5%~106.5%,相对标准偏差(RSD)为1.6%。结果表明:稻米中锗含量为0.738 2μg/g、米糠中锗含量为3.971 3μg/g、稻秆中锗含量为7.597 9μg/g、稻壳中锗含量为13.644 0μg/g、稻叶中锗含量为14.906 1μg/g。     

盐湖资源的开发和综合利用技术

中国是世界上盐湖资源最丰富的国家之一,钾、钠、锉、镁资源储量巨大.随着我国国民经济特别是农业的持续发展,要以钾为龙头,注重资源的综合利用,加快盐湖资源的开发。本文评述了我国盐湖资源的特点、开发现状和现阶段盐湖资源开发和综合利用中有代表性的化工技术:冷结晶法生产氛化钾、从盐湖资源制取硫酸钾、卤水中锉的分离提取、水氯镁石脱水和热解技术以及盆湖资源的深加工和高值化。     

盐湖镁资源的开发和利用*

我国盐湖镁资源品位高、储量大、易于开采,但目前的开发利用明显滞后,在一定程度上影响了盐湖其它资源的可持续开发和综合利用。本文针对我国盐湖镁资源的特点,综述了和盐湖镁资源开发利用相关的氢氧化镁、氧化镁、金属镁、镁合金、氯氧镁水泥和镁质晶须的开发及研究进展,并对我国盐湖镁资源的开发利用提出了一些建议。     

中学化学课程资源包的设计和开发

课程资源包是课程资源的集合体,它具有容量大、活动性、适用性强和应用范围广等特点,在有效教学过程中被广泛应用。积极开发、利用和更新课程资源,不仅对于有效教学本身是一种促进,更是学生能力培养和教师专业发展的必要途径。在已有研究基础上,对化学课程资源的定义与类型、课程资源包的设计开发的途径和步骤等进行了探讨,并以人教版高中《有机化学基础》中“羧酸酯”为例就如何开发和利用化学课程资源包作了案例分析。     

锰(Ⅱ)呋喃甲醛Schiff碱催化苯乙烯环氧化的研究

自1979年Groves首先以金属卟啉模拟细胞色素P－450,实现烯烃的环氧化^[1]以来,仿单加氧酶催化环氧化烯烃就成为仿酶催化领域里的一个非常活跃的研究课题^[2-5],但在这些报道中所用的模型化合物均为金属卟啉及其衍生物或Mn-Salen及其衍生物,这些化合物高昂的价格极大地限制了其应用前景。呋喃甲醛（俗称糠醛）取之于米糠或玉米芯,价格便宜且非石化产品,用它取代水杨醛不仅可降低成本,而且符合绿色化学要求。为此,本文选取了五种锰呋喃甲醛Schiff碱配合物作为模型化合物,以NaOCI为氧化剂,催化苯乙烯环氧化。讨论了配体结构、氧化物的pH值、轴配体、反应时间对催化环氧化反应的影响。     

Production of fumaric acid using rice bran and subsequent conversion to succinic acid through a two-step process

The fungal production of fumaric acid using rice bran and subsequent bacterial conversion of succinic acid using fungal culture broth were investigated. Since the rice bran contains abundant proteins, amino acids, vitamins, and minerals, it is suitable material that fungi use as a nitrogen source. The effective concentration of rice bran to produce fumaric acid was 5 g/L. A large amount of rice bran caused excessive fungal growth rather than enhance fumaric acid production. In addition, we could produce fumaric acid without the addition of zinc and iron. Fungal culture broth containing appro × 25 g/L of fumaric acid was directly employed for succinic acid conversion. The amount of glycerol and yeast extract required for succinic acid conversion was reduced to 70 and 30%, respectively, compared with the amounts cited in previous studies.     

Gastroprotective Activities of Ethanol Extract of Black Rice Bran (Oryza sativa L.) in Rats

Black rice is a type of rice in the Oryza sativa L. species. There are numerous reports regarding the pharmacological actions of black rice bran, but scientific evidence on its gastroprotection is limited. This study aimed to evaluate the gastroprotective activities of black rice bran ethanol extract (BRB) from the Thai black rice variety Hom Nil (O. sativa L. indica) as well as its mechanisms of action, acute oral toxicity in rats, and phytochemical screening. Rat models of gastric ulcers induced by acidified ethanol, indomethacin, and restraint water immersion stress were used. After pretreatment with 200, 400, and 800 mg/kg of BRB in test groups, BRB at 800 mg/kg significantly inhibited the formation of gastric ulcers in all gastric ulcer models, and this inhibition seemed to be dose dependent in an indomethacin-induced gastric ulcer model. BRB could not normalize the amount of gastric wall mucus, reduce gastric volume and total acidity, or increase gastric pH. Although BRB could not increase NO levels in gastric tissue, the tissue MDA levels could be normalized with DPPH radical scavenging activity. These results confirm the gastroprotective activities of BRB with a possible mechanism of action via antioxidant activity. The major phytochemical components of BRB comprise carotenoid derivatives with the presence of phenolic compounds. These components may be responsible for the gastroprotective activities of BRB. The 2000 mg/kg dose of oral BRB showed no acute toxicity in rats and confirmed, in part, the safe uses of BRB.     

Phytochemical study,potential cytotoxic and antioxidant activities of selected food byproducts (Pomegranate peel,Rice bran,Rice straw & Mulberry bark)

Abstract

The aim of the study is to evaluate common food by-products (Pomegranate peel, Rice bran, Rice straw & Mulberry bark) to screen out their medicinal importance such as cytotoxic & antioxidant activities. HPLC revealed that all tested samples were rich in phenolics. Tested samples exerted significant antioxidant activity with high potency to Pomegranate peel. All tested extracts were able to reduce cell viability of tested cell lines in a dose-response manner after treatment. In most cases, the IC50 values were under 30 μg/ml except IC50 of pomegranate peel against breast cell line (42.4?ug/ml). The antioxidant and cytotoxic properties of pomegranate peel, rice bran, rice straw and mulberry bark have been attributed to synergetic effects of phenolic phytochemicals.     

Treated Rice Bran for Scavenging Cr(III) and Hg(II) from Acidic Solution

The purpose of this study was to examine the efficiency with which rice bran (treated or untreated) removes heavy metals, especially Cr(III) and Hg(II), from acidic solution. Sorption assays were done in shaken flasks in the presence of rice bran. Different experimental conditions such as pH, volume of solution, bran weight, particle size, exchange time and stirring time were improved. The efficiency of bran was studied before and after treatments. For treatment, solutions of acid, alkali and salt were used. The results show that after treating with 4 M sodium chloride solution, its efficiency in removal of Cr(III) and Hg(II) was improved. Kinetic measurements of chromium and mercury removal by bran have revealed that sorption equilibrium was obtained after 10 min of contact. Sorption experiments done with various granulometric fractions of rice bran have shown that this sorbent has the same efficiencies in meshes higher than 20. Further research is necessary in order to determine a mechanism for cations removal by the bran. It is mentioned that the process of making polished rice from brown rice discharges rice bran; therefore, it is very inexpensive, with a cost of 1/50 ? 1/40 of that of synthetic sorbent, and thus its use would significantly lower the cost of wastewater treatment.     

The Health-Promoting Properties and Clinical Applications of Rice Bran Arabinoxylan Modified with Shiitake Mushroom Enzyme—A Narrative Review

Rice bran arabinoxylan compound (RBAC) is derived from defatted rice bran hydrolyzed with Lentinus edodes mycelial enzyme. It has been marketed as a functional food and a nutraceutical with health-promoting properties. Some research has demonstrated this rice bran derivative to be a potent immunomodulator, which also possesses anti-inflammatory, antioxidant, and anti-angiogenic properties. To date, research on RBAC has predominantly focused on its immunomodulatory action and application as a complementary therapy for cancer. Nonetheless, the clinical applications of RBAC can extend beyond cancer therapy. This article is a narrative review of the research on the potential benefits of RBAC for cancer and other health conditions based on the available literature. RBAC research has shown it to be useful as a complementary treatment for cancer and human immunodeficiency virus infection. It can positively modulate serum glucose, lipid and protein metabolism in diabetic patients. Additionally, RBAC has been shown to ameliorate irritable bowel syndrome and protect against liver injury caused by hepatitis or nonalcoholic fatty liver disease. It can potentially ease symptoms in chronic fatigue syndrome and prevent the common cold. RBAC is safe to consume and has no known side effects at the typical dosage of 2–3 g/day. Nevertheless, further research in both basic studies and human clinical trials are required to investigate the clinical applications, mechanisms, and effects of RBAC.     

Macrophage-stimulating activity of exo-biopolymer from cultured rice bran with <Emphasis Type="Italic">Monascus pilosus</Emphasis>

To find a new use of rice bran, five fungi were examined for the production of exo-biopolymer with macrophage-stimulating activity from rice bran. Among the exo-biopolymers produced from the cultures, Monascus pilosus had the most potent macrophage stimulating activity in a liquid culture rather than in a solid culture. In order to improve the yield of exo-biopolymer with macrophage-stimulating activity, a suitable medium for exo-biopolymer was tested in submerged culture of M. pilosus. The highest amount of exo-biopolymer (13.9 mg/mL) was obtained in a medium containing rice bran as an only carbon source followed by media with additional maltose and sucrose (13.8 and 13.7 mg/mL, respectively). The addition of peptone resulted in the production of high amount of exo-biopolymer (15.1 mg/mL), meanwhile the addition of ammonium chloride resulted in 264.0 μg/mL of glucosamine content. Among eight different kinds of inorganic salts tested, potassium phosphate (0.1%) was the most effective inorganic salt for the mycelial growth and exo-biopolymer production. Therefore the optimal medium composition was as follows (g/L): 20 g of rice bran, 5 g of peptone, and 1 g of KH₂PO₄. The optimal culture pH and time for mycelial growth and exo-biopolymer production was pH 5.0 and 25°C, respectively. The maximum exo-biopolymer (20.1 mg/mL) was observed at the fourth day of cultivation. Exo-biopolymer, a crude polysaccharide fraction, mainly contained neutral sugar (81.8%) with considerable amounts of uronic acid (18.2%). Component sugar analysis showed that the active fraction consisted mainly of arabinose, galactose, glucose, which was digested from starch of rice bran during cultivation, and uronic acid (molar ratio; 0.8:1.0:0.7:0.8).     

傅里叶变换红外吸收光谱识别五种植物油的研究

以花生油、大豆油、芝麻油、棉籽油和米糠油为样品,采用傅里叶变换红外光谱仪,采集傅里叶变换红外吸收光谱,对光谱预处理后,提取红外特征信息,以1746cm-1和2855cm-1处的吸收峰面积比值为横坐标,1099cm-1处与1119cm-1处的吸收峰面积比为纵坐标,在Origin6.0上做出二维分布图,对各种油脂进行识别分析。结果显示,大豆油与其它4种油脂之间有明显区分;大豆油、花生油和芝麻油分布效果好,但棉籽油各样品点之间比较分散;能与其它油脂区分开的有以下几种分布花生油明显区别于芝麻油、棉籽油和大豆油;米糠油明显区别于棉籽油和大豆油。分布有交叉的油脂有米糠油与花生油或芝麻油有交叉,棉籽油与芝麻油有交叉。