Phytosterols and γ‐oryzanol in rice bran oils and distillates from physical refining process

Commercially available refined rice bran oil (RBO) contained high contents of phytosterol and γ‐oryzanol, that is, 858–1034 and 248–887 mg per 100 g oil, respectively. Although the crude rice bran oil (CRBO) had high contents of both phytochemicals (1362–1376 mg phytosterol per 100 g and 1599–1666 mg γ‐oryzanol per 100 g), physical refining process resulted in their reduction to 820–895 mg phytosterol per 100 g and 933–960 mg γ‐oryzanol per 100 g in RBO (P < 0.05). Both phytochemicals evaporated and accumulated in the deodoriser distillate (DD) to some extent during the deodorising step. Further distillation of DD using molecular distillation (MD) evaporated the free fatty acids (FFAs), resulting in the unevaporated fraction (UMD) having the acid values of 5.6–9.3 mg KOH g^?1. The UMD also contained 1585–3391 mg phytosterol per 100 g and 781–848 mg γ‐oryzanol per 100 g. Results suggest potential use of DD as the source of phytochemicals for further concentration by MD.     

气质联用法分析植物甾醇酯

建立了植物甾醇酯的气相色谱质谱分析方法。样品经正己烷超声溶解定容处理后,使用惠普6890-5973气相色谱质谱联用仪、DB-5HT色谱柱直接进行定性分析。本实验方法可靠,重复性好,专属性强,可用于植物甾醇酯中各组分的含量测定,以控制植物甾醇酯的质量,准确性和精确度高。     

植物甾醇及其环糊精包合物对高血脂小鼠降血脂实验研究

目的：评价植物甾醇经过β-环糊精及其衍生物包合作用对高血脂症小鼠血脂指标的影响。方法：将昆明小鼠分为6组,分别为正常组、高脂模型组、阳性对照组、植物甾醇组、β-环糊精/植物甾醇包合物组和羟丙基-β-环糊精/植物甾醇包合物组,建模给药测定其血脂水平。结果：给予不同药后,与模型组比较,阳性对照组和三个实验组均能显著降低TC、LDL-C和AI水平,提高HDL-C水平,且三个实验组之间各指标均没有显著性差异。结论：植物甾醇有显著的降血脂作用,而且经过β-环糊精和羟丙基-β-环糊精包合后不影响其降血脂功能。     

Phytosterol Enrichment of Rice Bran Oil by a Supercritical Carbon Dioxide Fractionation Technique

Supercritical carbon dioxide (SC–CO₂) fractionation technique was evaluated as an alternative process for reducing the free‐fatty‐acid (FFA) content and minimizing the phytosterol loss of rice bran oil (RBO) during the process. The effects of pressure (20.5 to 32.0 MPa) and temperature (45 to 80 °C) for isothermal operation of the column on the composition of the resultant fractions were examined. Low‐pressure and high‐temperature conditions were found to be favorable for minimizing triglycerides (TG) and phytosterol losses during the FFA removal from crude RBO. Rice bran oil fractions with < 1% FFA, about 95% TG, and 0.35% free sterol with 1.8% oryzanol content could be obtained utilizing the described SC–CO₂ fractionation technique.     

由塔尔油沥青中提取植物甾醇的研究

用碱皂化塔尔油沥青后用有机溶剂提取。结晶分离植物甾醇,经重结晶,提高植物甾醇的纯度。该方法可提取9.8%(以塔尔油沥青计)植物甾醇,经一次重结晶纯度可达93.2%。     

超声波法提取米糠中植物甾醇的工艺研究

植物甾醇是植物中广泛存在的一类具有重要生物活性的物质。采用超声波法从米糠中提取植物甾醇，以植物甾醇得率为指标。通过单因素实验和正交实验确定其优化工艺条件为：提取溶剂乙酸乙酯，料液比（w/v）1：15，提取温度70℃，提取时间90min，超声波功率160W。与热回流法比较，超声波法提取极大的缩短提取时间，而且提取得率略有提高。     

植物甾醇已二酸单酯的合成与固体纳米脂质粒的制备

以植物甾醇、己二酸为原料,二甲苯为溶剂,对甲苯磺酸为催化剂合成了植物甾醇己二酸单酯,并通过FT–IR、13C NMR、HPLC等分析手段证实了产物的结构;以植物甾醇己二酸单酯为原料,制备出固体纳米脂质粒。     

米糠油综合利用与制取工艺研究

该文介绍米糠油综合利用及其制取工艺方法,即以米糠油皂脚酸化油制取蒸馏浓缩物,并进一步制取各相关产品。     

Phytosterol Oxidation Products: Their Formation,Occurrence, and Biological Effects

Phytosterols or plant sterols are integral natural components of plant cell membranes that are abundant in vegetable oils, nuts, seeds, and grains; as well as added components in various functional foods. Due to their chemical structure, phytosterols are susceptible to oxidation under certain conditions giving rise to a family of compounds known as phytosterol oxidation products (POPs). The following review gives an in-depth account on the formation and occurrence of POPs in foodstuffs. The metabolism and biological effects of these oxides is also discussed in detail.     

Presence and metabolism of the anabolic steroid boldenone in various animal species: a review

The review summarizes current knowledge on the possible illegal use of the anabolic steroid boldenone. The presence of boldenone and metabolites in different animal species and the possibility of the occurrence of endogenous boldenone and metabolites is assessed, as are the methods of analysis used for detection. Different laboratories in the European Union have examined the occurrence of boldenone and its metabolites. The results were discussed at different meetings of a European Commission DG-SANCO Working Party and summarized in an expert report. The situation of the different laboratories at this time is also covered herein. The overall conclusion of the Working Party was that there was a necessity for further research to distinguish between naturally occurring and illegally used boldenone forms. The confirmation of the presence of boldenone metabolites (free and conjugated forms) in certain matrices of animals is proposed as a marker for the illegal treatment with boldenone.