Optimal Conditions for the Purification of Sesamin by Recrystallization

[Objective] Sesamin has been widely used in healthy food and medicines in recent years due to its prominent biological functions. This study was aimed to determine the optimal parameters for sesamin recrystallization, to obtain high-quality and high-purity sesamin. [Method] The effects of solid-liquid ratio, heating tempera- ture and cooling temperature on sesamin recrystallization were investigated by sin- gle-factor experiments and orthogonal array testing （ORT）. The purity of resulting sesamJn was investigated by HPLC, [Result] The optimal conditions for the purifica- tion of sesamin were solid-liquid ratio of 1：10, heating temperature of 45 ℃ and cooling temperature of 25 ℃. Under these conditions, the purity of sesamin reached 95.26%. [Conclusion] Recrystallization is an effective technique to purify sesamin from sesame meal. Moreover, HPLC is also an ideal method for analyzing the purity of sesamin.

Antioxidant lignans sesamin and sesamolin in sesame(Sesamum indicum L.):a comprehensive review and future prospects

Sesame(Sesamum indicum L.)is a significantly lucrative cash crop for millions of small-holder farmers.Its seeds are an important source of a highly appreciated vegetable oil globally and two clinically essential antioxidant lignans,sesamin and sesamolin.Accordingly,many countries import millions of tons of sesame seed every year.The demand for lignan-rich sesame seeds has been increasing in recent years due to the continuous discovery of several pharmacological attributes of sesamin and sesamolin.To meet this demand,the sesame breeder’s primary objective is to release sesame cultivars that are enriched in oil and lignans.Thus,it is necessary to summarize the information related to the sesamin and sesamolin contents in sesame in order to promote the joint efforts of specialized research teams on this important oilseed crop.In this article,we present the current knowledge on the sesamin and sesamolin contents in S.indicum L.with respect to the updated biosynthesis pathway,associated markers,governing loci,available variability in sesame germplasm,the in planta potential roles of these compounds in sesame,and the newly discovered pharmacological attributes.In addition,we propose and discuss some required studies that might facilitate genomics-assisted breeding of high lignan content sesame varieties.

Inhibition of two stages of melanin synthesis by sesamol,sesamin and sesamolin

Objective: To investigate the antimelanogenesis properties of three sesame compoundssesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents.Methods: Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and b-arbutin, in order to evaluate:(a) the sunscreen function of sesamol, sesamin and sesamolin by measurement of UV absorbtion property;(b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and(c) the effect on melanin content and melanogenic protein expression(tyrosinase, TRP-1 and TRP-2) by Western blot analysis; and(d) the toxicity of sesamol, sesamin and sesamolin to cells using cell cytotoxicity assay.Results: The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm. Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition(IC_(50) of 1.6 μM) followed by sesamin, sesamol, and kojic acid,respectively. The order from high to low inhibition of melanin pigment was detected in the SK-MEL2 treated with sesamolin, sesamin, sesamol, kojic acid, and b-arbutin,respectively. Sesamolin and sesamin successfully inhibited cellular tyrosinase activity and respectively decreased TRP-1/TRP-2(36%/15%) and TRP-1 levels(16%), thereby inhibiting melanogenesis via antityrosinase activity. No cytotoxicity to SK-MEL2 or Vero(normal) cell lines was observed at the lignan concentrations that exerted an antimelanogenic effect.Conclusions: Three sesame lignans prevent melanin synthesis through 2 stages:(a) by blocking melanin-induction and(b) by interrupting melanogenic enzyme production. This study provides evidence that sesamol, sesamin and sesamolin are potential for antimelanogenesis agents.

Sesamin enhances nitric oxide bioactivity in aortas of spontaneously hypertensive rats

OBJECTIVE To explore the underlying mechanisms involved in the effect of sesamin on aortic NO bioactivity in spontaneously hypertensive rat(SHR).METHODS Sesamin was orally administered for consecutive 8 weeks in SHR.Systolic blood pressure(SBP)was measured using the tail-cuff method.The aortas were isolated and in vitro vascular reactivity studies were performed.Superoxide anion production in carotid arteries was assessed by dihydroethidium fluorescence staining.The protein expression of endothelial nitric oxide synthase(eNOS),phosphorylated eNOS(P-eNOS),dihydrofolate reductase(DHFR),nicotinamide adenine dinucleotide phosphate(NADPH)oxidase subunit p47 phox and copper,zinc-superoxide dismutase(Cu/Zn-SOD)in aortas was detected by Western blotting.The dimeric form of eNOS in aortas was determined by low-temperature SDS-PAGE.Aortic level of nitrotyrosine and activities of antioxidant enzymes,namely,total SOD(T-SOD),glutathione peroxidase(GPx)and catalase were also detected.RESULTS In SHR,sesamin treatment reduced SBP,improved vascular relaxation induced by acetylcholine and enhanced aortic NO bioactivity.Sesamin treatment enhanced NO biosynthesis in SHR aortas was due to upregulated P-eNOS and suppressed eNOS uncoupling,and the latter effect might be attributed to decreased nitrotyrosine and upregulated DHFR.Sesamin also reducd the NO oxidative inactivation and decreased the superoxide anion production through downregulation of p47 phox and amelioration of eNOS uncoupling.In addition,sesamin treatment did not alter the levels of GPx and catalase activity but obviously reduced the compensatory elevated T-SOD activity and Cu/Zn-SOD protein expression.CONCLUSION Chronic treatment with sesamin could reduce hypertension and improve endothelial dysfunction through enhancement of NO bioactivity in SHRs aortas.

Separation of Sesamin and Sesamolin by a Supercritical Fluid-Simulated Moving Bed

This work shows how the sesamin and sesamolin in sesame seed can be extracted, enriched and purified by the related technologies of supercritical carbon dioxide. Sesame oil is first obtained from the sesame seeds by supercritical carbon dioxide extraction (SFE);lignans in the oil are enriched and precipitated as the top product by supercritical fluid fractionation technology (SFF);the crude lignans are then separated by supercritical fluid-simulated moving bed chromatography (SF-SMB) to obtain pure sesamin and sesamolin. The simulated moving bed is a continuous chromatography;the use of supercritical carbon dioxide as the desorbent simplifies the downstream treatment. By experimental validation, this work also shows that replacing liquid by SF as the desorbent for the SMB automatically creates a gradient operation for the SMB and enlarges the separable range of the operating conditions. Both the design and operation of the SF-SMB are introduced in this paper. The application of SF-SMB to the separation of sesamin and sesamolin provides a novel example for demonstrating the diversity of SF and the potential applications for the production of natural products and the development of botanical drugs.

Identification and determination of (+)-sesamin in Semen Cuscutae by capillary GC and GC-MS

(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-sesamin and CC-MS for its identification. The result suggested that this approach could be used to identify Semen Cuscutae from various sources based on the different content of(+)-sesamin in them.

Effect of Temperature Variation on the Separation of Sesamin and Sesamolin by Simulated Moving Bed

In this work, sesamin and sesamolin is separated and purified by SMB （simulated moving bed） chromatography. Purity of sesamin and sesamolin can reach 99.2% and 99.9 %, and they can be recovered by 99.9% and 99.4%, respectively. Concentrations of the extract and raffinate was monitored and periodical change of the concentration was observed on experiment. Effects of non-linear adsorption, dead volume, and temperature on the separation are reviewed by the triangle theory to explain the periodical change of concentration. It is found that dead volume has little effect, and temperature fluctuation significantly affects thc separation by SMB. The temperature seriously affects the robust operation of SMB due to the change of Henry＇s constant, which will change the selectivity and restrain the productivity. Although the productivity in this study is only 0.0416 g/L-hr, the cost of the stationary phase used in this study is much lower than that of packed in analytical column. By using this stationary phase, the authors are still able to separate the mixture of sesamin and sesmolin. This will economically attract attention for the application of SMB to purify bioactive compounds on developing botanical drugs.

Effect of Arbuscular Mycorrhizal Fungi and Their Partner Bacteria on the Growth of Sesame Plants and the Concentration of Sesamin in the Seeds

Arbuscular mycorrhizal fungi (AMF) can stimulate the plant growth. Pseudomonas sp. (KCIGC01) NBRC109613 isolated from the spores of Glomus clarum IK97, an AMF, is reported to support the plant growth and development as partner bacteria (PB) for AMF REF _Ref399417929 \r \h \* MERGEFORMAT [1]. In order to investigate the effect of G. clarum IK97 and Pseudomonas sp. (KCIGC01) NBRC109613 on the secondary metabolites, these microorganisms were inoculated to sesame plants. The inoculation of these microorganisms stimulated the growth of sesame. The rate of sesame root colonization in G. clarum IK97 + Pseudomonas sp. (KCIGC01) NBRC109613 inoculated plants (66.4% ± 4.4%) was higher than that in G. clarum IK97 alone inoculated plants (39.2% ± 5.8%). Furthermore, the content of sesamin in sesame seeds was increased by the inoculation of these microorganisms. In particular, the content of sesamin in the treatment inoculated with G. clarum IK97 and Pseudomonas sp. (KCIGC01) NBRC-109613 was 11.4 ± 1.5 mg/g seed. The results suggest that AMF and their partner bacteria can stimulate the growth and development of sesame plants and increase the content of sesamin in the seeds.

Potential immunomodulatory role of sesamin in combating immune dysregulation associated with COVID-19

The ongoing outbreak of novel coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has caused an unprecedented global health crisis.Development of a cure for this devastating disease is currently at full speed,with several vaccines against COVID-19 already authorized and administered.Currently,demand for these vaccines far exceeds supply.As such,boosting immunity represents a viable route to halt the rapid spread of SARS-CoV-2 and limit fatalities until vaccines become more readily and widely available.The use of phytochemicals appears to be a promising panacea.Sesamin,a lignan isolated from Sesamum indicum seeds,is known for its potent pharmacological properties,and is therefore hypothesized as a potential candidate in the therapeutic regimen against COVID-19.Herein,we highlight the confirmed therapeutic anti-inflammatory and immune-modulatory potential of sesamin against myriads of respiratory disorders,and tentatively suggest that sesamin may exert similar potent effects against COVID-19.Precisely,we speculate that sesamin may help alleviate COVID-19 via restoring Th1/Th2 balance and preventing inflammation and cytokine storm development.Additionally,we further support the promising role of sesamin against COVID-19 by underscoring the direct evidence,which suggests that sesamin may demonstrate promising inhibitory potential against three important SARS-CoV-2 targets,namely main protease,spike protein,and angiotensin-converting enzyme 2 receptor.Although preliminary,there is ample evidence to propose sesamin as a potential phytotherapeutic and prophylactic candidate against COVID-19.Further in vitro,in vivo,and preclinical studies are required to further substantiate the role of sesamin in the prevention and/or treatment of COVID-19.

Beneficial Regulatory Effects of Sesamin on Intestinal Flora of Mice

The effects of sesamin on intestinal microflora of mice with normal diet were studied by in vitro animal feces anaerobic culture system.The results showed that treatment with sesamin could significantly change the intestinal flora structure of mice,increasing the abundance of probiotics Lactobacillus and Bifidobacterium and inhibiting the growth of harmful bacteria Enterococcus.High-throughput sequencing analysis showed that sesamin could affect the structure and composition of fecal microflora of mice,and the abundance of probiotics such as Bacillus and Bifidobacterium increased.Sesamin also could increase the expression of tight contiguous protein Occludin and Claudin-1 in colonic tissue of mice,which was benefit to the adhesion of probiotics.In conclusion,sesamin intervention could improve the composition and abundance of intestinal microorganisms in mice with normal diet,which had a beneficial regulatory effect on the intestinal health.

芝麻素对长春瑞滨诱导人肺腺癌A549细胞凋亡的影响

[目的]探讨芝麻素对长春瑞滨诱导人肺腺癌A549细胞株凋亡的影响.[方法]选择人肺腺癌A549细胞株进行体外传代培养,制备成浓度为1.0×105个/mL的细胞悬浮液并接种于96孔板中.实验设空白组(加入DMEM培养液)、对照组(加入DMEM培养液及人肺腺癌A549细胞株)、芝麻素组(芝麻素10、20、30、40、50、60、70、80、90、100μg/mL)、长春瑞滨组(长春瑞滨5、10、15、20、25、30、35μg/mL)及联合用药组(加入IC50浓度的芝麻素和长春瑞滨,IC50为后续联合用药组实验药物浓度).空白组加入160μL的DMEM培养液,对照组及实验组各加入160μL已制备好的人肺腺癌A549细胞株悬浮液,待细胞株贴壁后,空白组、对照组及实验组分别加入20μL的生理盐水和20μL各相关浓度的药物.采用MTT法检测细胞增殖能力,利用倒置显微镜及HE染色法观察细胞形态学变化,采用流式细胞仪检测细胞凋亡情况.[结果]在10~100μg/mL质量浓度范围内,低质量浓度的芝麻素具有抑制A549细胞株增殖的作用,IC50质量浓度为40μg/mL;在5~35μg/mL质量浓度范围内,长春瑞滨具有抑制A549细胞株增殖的作用,且随着药物质量浓度升高细胞抑制率升高,IC50质量浓度为20μg/mL;芝麻素与长春瑞滨联合用药对A549细胞株的抑制率明显高于单药用药(P<0.01).倒置显微镜及HE染色法观察结果显示,与对照组比较,芝麻素(40μg/mL)、长春瑞滨(20μg/mL)及联合用药(芝麻素40μg/mL+长春瑞滨20μg/mL)作用于A549细胞株48 h后贴壁细胞数量均明显减少,细胞间连接疏松,贴壁能力减弱,部分细胞体积变小、变圆或呈不规则形,核染色质凝集,细胞膜起泡形成凋亡小体,失去原有肿瘤细胞多角形或梭形形态,且联合用药组较单药组上述变化更为明显.流式细胞仪检测结果显示,药物作用48 h后,芝麻素组(40μg/mL)、长春瑞滨组(20μg/mL)及联合用药组(芝麻素40μg/mL+长春瑞滨20μg/mL)细胞凋亡率均明显高于对照组(P<0.01),且联合用药组早期凋亡率明显高于单独用药组(P<0.01).[结论]芝麻素可增强长春瑞滨诱导人肺腺癌A549细胞凋亡的作用.

菟丝子治疗骨关节炎:网络药理学分析及实验验证

背景:菟丝子具有补肝肾、益精髓的功效,而骨关节炎的主要病机为肝肾亏虚,推测菟丝子与骨关节炎之间有一定的联系。目的:基于网络药理学和分子对接的分析手段挖掘骨关节炎和菟丝子之间的潜在联系,对中药本草菟丝子的作用机制进行合理的推测与验证。方法:先在中草药数据库TCMSP中筛选菟丝子的有效活性成分和作用靶点,另在疾病数据库GeneCards、OMIM、TTD中收集骨关节炎的相关基因;取交集后进行一系列分析,并筛选出核心基因;通过对核心基因的富集分析选择菟丝子作用于骨关节炎的通路,通过分子对接验证核心基因的作用,并依此选择合适的有效活性成分进行实验验证。结果与结论:①筛选出11种菟丝子的有效活性成分,菟丝子和骨关节炎有66个交集靶点基因,后续筛选出12个核心基因,包括肿瘤坏死因子、白细胞介素1B、TP53、RACα丝氨酸/苏氨酸蛋白激酶(AKT1)、血管内皮生长因子A、基质金属蛋白酶9、前列腺素过氧合酶2、胱天蛋白酶3、表皮生长因子、过氧化物酶体增生激活受体γ、白细胞介素10、血管细胞黏附因子1;②对核心基因进行富集分析后,选择经典炎症通路核因子κB信号通路进行后续菟丝子缓解骨关节炎炎症的分析验证;根据各活性成分和通路核心基因前列腺素过氧合酶2进行分子对接后得到的结果,选择亲和力最高的芝麻素进行后续细胞实验验证,结果证实了菟丝子的有效成分芝麻素可以通过抑制白细胞介素1β诱导的核因子κB信号通路降低环氧合酶2的表达;③结果表明,菟丝子的活性有效成分芝麻素通过抑制白细胞介素1β诱导的核因子κB信号通路降低环氧合酶2的表达,达到改善骨关节炎炎症的作用,证实了菟丝子在骨关节炎方面的治疗效果。

芝麻素与细辛素检测方法及生物活性的研究进展

旨在为芝麻木酚素相关产品、特殊用途油脂等的研发提供参考,对芝麻木酚素中主要的脂溶性活性成分芝麻素及其转化产物细辛素的含量分布、转化条件、检测方法和生物活性进行综述。芝麻素是芝麻中含量最多的脂溶性木酚素,而芝麻中几乎不含细辛素,但芝麻素可在酸性和受热条件下转化为细辛素;芝麻素与细辛素的检测方法有高效液相色谱法、薄层色谱法、气相色谱-质谱联用法、液相色谱-质谱联用法等;芝麻素具有抑菌、抗癌、降血脂等生物活性,细辛素具有抗炎、抑菌、抗病毒、抗癌、抗肿瘤、抗氧化等生物活性。

PrxⅤ在芝麻素增强吉西他滨诱导的肺癌细胞凋亡中的作用机制

[目的]探讨PrxⅤ在芝麻素增强吉西他滨诱导的人肺腺癌A549细胞凋亡中的作用机制,旨在为肺癌的治疗提供靶点.[方法]取人肺腺癌A549细胞株体外培养48 h,采用MTT法检测不同浓度吉西他滨及芝麻素作用下的A549细胞的存活率,并计算半数抑制浓度.[结果]吉西他滨、芝麻素作用于人肺腺癌A549细胞的半数抑制浓度分别为7、45μmol/L.划痕实验结果显示联合用药组划痕修复率显著低于单用药组(P<0.05,P<0.01).TUNEL染色结果显示联合用药组凋亡细胞数显著高于吉西他滨组和芝麻素组(P<0.01).JC-1荧光探针标记检测结果显示联合用药组细胞中线粒体膜电位降低幅度显著高于吉西他滨组和芝麻素组(P<0.05).荧光探针DCFH-DA检测结果显示吉西他滨组和芝麻素组细胞ROS水平显著低于联合用药组.蛋白印迹实验结果显示吉西他滨和芝麻素均可抑制A549细胞中PrxⅤ表达,联合用药组抑制作用更为显著.[结论]吉西他滨和芝麻素均可抑制人肺腺癌A549细胞的增殖和迁移,且芝麻素可增强吉西他滨的上述作用;吉西他滨可降低PrxⅤ表达,从而减弱PrxⅤ对人肺腺癌A549细胞的保护作用,芝麻素可增强吉西他滨的这一作用;吉西他滨和芝麻素可降低人肺腺癌A549细胞内PrxⅤ表达,升高细胞内ROS水平,降低线粒体膜电位,从而使细胞发生凋亡.

芝麻花生混合压榨调和油储藏稳定性的研究

旨在为提高油脂储藏稳定性提供参考,以花生油为原料,通过Schaal烘箱法,在考察芝麻素对花生油储藏稳定性影响的基础上,考察调和油2种制备方式(植物油直接混合、原料混合再压榨)对芝麻花生调和油储藏稳定性的影响。结果表明:添加芝麻素可降低花生油储藏期间的酸值、过氧化值、茴香胺值、共轭二烯值、共轭三烯值、巴比妥酸值,延长氧化诱导时间;将芝麻与花生混合后再压榨制备的调和油的储藏稳定性优于芝麻油与花生油直接混合制备的调和油的。综上,芝麻油可提高花生油的储藏稳定性,且混合压榨法可作为制备调和油的一种更好选择。

芝麻素松脂素及黑芝麻产品对酪氨酸酶活性和黑色素含量生成影响

黑芝麻富含芝麻素、松脂素等活性成分,具有滋养脾肺、补肝益肾、养发黑发的功能。毛发颜色与毛囊内黑素细胞酪氨酸酶激活促进黑色素的生成水平密切相关。以人体黑素细胞结构较相似的小鼠黑色素瘤细胞B16为对象,研究黑芝麻中芝麻素、松脂素及黑芝麻产品对B16细胞内酪氨酸酶活性和黑色素生成的影响。结果表明,芝麻素和松脂素可提高B16细胞内酪氨酸酶的活性,促进黑色素生成。核桃芝麻黑豆粉和黑芝麻丸产品醇和水提取物也具有促进B16细胞内酪氨酸酶活性和黑色素生成的作用。因此,芝麻素和松脂素及黑芝麻产品能有效促进黑色素生成,可能具有乌发潜力。

芝麻素对高糖损伤SH-SY5Y细胞的保护效果及机制

目的研究芝麻素(sesamin)对高糖所致人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。方法SH-SY5Y细胞接种于含100 mmol/L葡萄糖的培养基并与10、20、40μmol/L芝麻素共同孵育36 h,MTT法测定细胞存活率,比色法测定细胞培养液乳酸脱氢酶(LDH)水平,ELISA检测DNA片段及半胱氨酸天冬氨酸蛋白酶-3(Caspase-3)活性。2',7'-二氯荧光黄双乙酸盐(DCFH-DA)探针法检测细胞中活性氧(ROS)的水平,试剂盒检测细胞内丙二醛(MDA)、超氧化物岐化酶(SOD)、过氧化氢酶(CAT)和还原型谷胱甘肽(GSH)活性。光度法检测细胞烟酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶活性,实时荧光定量检测NADPH氧化酶亚基p47phox mRNA表达。Western blot法检测p47phox蛋白表达。结果芝麻素可增加高糖作用下SH-SY5Y细胞的存活率,抑制细胞LDH释放,阻止高糖诱导的DNA断裂,降低Caspase-3活性。同时芝麻素能够增加高糖作用下SH-SY5Y细胞内SOD、CAT和GSH的活性,清除细胞内的ROS,抑制NADPH氧化酶活性及p47phox mRNA和蛋白的表达。结论芝麻素对高糖诱导SY5Y细胞损伤具有保护作用,其机制可能与抗氧化和抑制NADPH氧化酶活性有关。

芝麻素的应用性能研究

采用滤纸片法和平板培养法研究了芝麻特征性成分芝麻素的抗菌活性,结果表明,芝麻素对细菌的抑(杀)作用显著,且对细菌的最低抑制浓度(MIC)为0.1%;在实验浓度范围内,芝麻素对真菌基本无抑制作用。另外以过氧化值(POV)为指标研究了芝麻素对大豆色拉油和花生油的抗氧化性能,结果表明,芝麻素具有良好的抗油脂氧化活性,ω(芝麻素)=0.04%在大豆色拉油中的抗氧化活性与ω(BHT)=0.02%相当。

国产芝麻中芝麻素含量分析

本文分析了国内重点芝麻产区15种芝麻的芝麻素含量,并分析芝麻素含量与芝麻品质之间的关系;结果表明:麻油中芝麻素的含量为0.115%～0.777%,芝麻素含量与芝麻含油率呈正相关(相关系数0.556,(α=0.05)。芝麻素平均含量以白芝麻最高,棕黄色芝麻稍逊,黑芝麻次之。

芝麻油中芝麻素、芝麻林素的研究

本文利用高效液相色谱测定不同芝麻样本提取油以及市购芝麻油中芝麻素、芝麻林素的含量。色谱柱为HibarRT250-4(C18,250mm×4.6mm,填充粒度5μm);流动相:甲醇:水=75:25(V/V);流速:1ml/min;检测波长:280nm。测定结果表明:被测两峰完全分离,且峰形较好,线性范围10～100μg/ml,芝麻素、芝麻林素平均回收率分别为101.1%、100.2%重现性(n=5)分别为芝麻素RSD=2.31%、芝麻林素的RSD=3.05%,最低检出限:芝麻素为1.5μg/ml,芝麻林素为2.5μg/ml(以进量浓度计)。油样中芝麻素的含量范围为0.35%～0.72%、芝麻林素的含量范围为0.32%～0.48%,制油工艺中焙炒工序强度对芝麻林素含量变化具有一定影响。