Fine Mapping of a Major Pleiotropic QTL Associated with Sesamin and Sesamolin Variation in Sesame (Sesamum indicum L.)

Deciphering the genetic basis of quantitative agronomic traits is a prerequisite for their improvement. Herein, we identified loci governing the main sesame lignans, sesamin and sesamolin variation in a recombinant inbred lines (RILs, F8) population under two environments. The content of the two lignans in the seeds was investigated by HPLC. The sesamin and sesamolin contents ranged from 0.33 to 7.52 mg/g and 0.36 to 2.70 mg/g, respectively. In total, we revealed 26 QTLs on a linkage map comprising 424 SSR markers, including 16 and 10 loci associated with sesamin and sesamolin variation, respectively. Among them, qSmin_11.1 and qSmol_11.1 detected in both the two environments explained 67.69% and 46.05% of the phenotypic variation of sesamin and sesamolin, respectively. Notably, qSmin11-1 and qSmol11-1 were located in the same interval of 127-127.21cM on LG11 between markers ZMM1776 and ZM918 and acted as a pleiotropic locus. Furthermore, two potential candidate genes (SIN_1005755 and SIN_1005756) at the same locus were identified based on comparative transcriptome analysis. Our results suggest the existence of a single gene of large effect that controls expression, both of sesamin and sesamolin, and provide genetic information for further investigation of the regulation of lignan biosynthesis in sesame.

Effect of Sesame Lignan Supplementation on Carotid Intima-Media Thickness, Serum Lipid Profile, Serum VEGF, VCAM-1, ICAM-1 and vWF Levels in Cardiovascular Disease Patients

Background: Atherosclerosis is a chronic inflammatory disease of the vascular wall which can alter the whole vascular system of both the aorta and coronary arteries. Sesame seeds are one of the richest sources of dietary lignans which exhibit diverse functions and valuable effects such as anti-hypertensive, anti-inflammatory, and anti-oxidative activities. Objectives: In this study, the Effect of sesame lignans on carotid intima-media thickness (CIMT), serum lipid profile, and serum levels of VEGF, VCAM-1, ICAM-1 and vWF were evaluated in cardiovascular (CVD) patients. Methods: In this double-blind, randomized, placebo-controlled clinical trial, thirty-six CVD patients who were candidates for angiography participated for 10 weeks. The subjects were asked to use 500 mg/day sesame lignans (lignan group, n = 19) or placebo (placebo group (starch), n = 17). The CIMT was measured by ultrasound and fasting blood samples were taken before and after the intervention. Results: Sesame lignans supplementation showed a significant decrease in both left and right CIMT, serum lipid profile, fasting blood glucose, and ICAM-1 serum levels compared to baseline and placebo (P < 0.05). Conclusions: These findings indicate that sesame lignans may contribute to the reduction of CIMT and prevent future cardiovascular events and so may be considered as a complementary therapeutic approach in CVD

Sesame lignans increase sympathetic nerve activity and blood flow in rat skeletal muscles

Beneficial effects of sesame lignans, especially antioxidative effects, have been widely reported; however, its potential effects on autonomic nerves have not yet been investigated. Therefore, the current study aimed to investigate the effect of sesame lignans on the autonomic nervous system. The sympathetic nerve activity in rat skeletal muscle was measured using electrophysiological approaches, with blood flow determined using the laser Doppler method. Sesame lignans were administered intragastrically at 2 and 20 mg/kg, and after 60 min, the sympathetic nerve activity was observed to increase by 45.2 % and 66.1 %, respectively. A significant increase in blood flow (39.6 %) was also observed for the 20-mg/kg dose when measured at 55 min after administration. These sympathomimetic effects were completely prevented by subdiaphragmatic vagotomy, and the increase in blood flow was eliminated in the presence of the β2-adrenergic receptor inhibitor butoxamine. Thus, it is proposed that sesame lignans can increase the blood flow of skeletal muscle, possibly by exciting sympathetic nerve activity through the afferent vagal nerve.

Antioxidant activity of sesame seed lignans in sunflower and flaxseed oils

This study investigated the antioxidant activity of crude lignan extracts and purified lignans (sesamin, sesamolin, and sesamol) in sunflower and flaxseed oils. Lignan extracts were prepared from roasted sesame seed oil (LRSO) and unroasted sesame seed oil (LUSO). Additionally, the individual lignans were purified from both oils. The crude extracts and purified lignans were added at concentrations of 0.01, 0.02 and 0.03% to the oils and stored at 25 and 65°C over time and peroxide values and thiobarbituric acid values were measured. Each oil showed an increase in oxidation over time, with the samples stored at 65°C exhibiting accelerated oxidation. In general, LRSO showed higher antioxidant activity than LUSO and the antioxidant activity was similar to the antioxidant activity of butylated hydroxytoluene (0.02% BHT) in both oils when used at concentrations of 0.02 and 0.03%. Sesamol showed the highest antioxidant activity of each of the purified lignans followed by sesamin and sesamolin respectively. Crude and purified sesame lignans may have potential applications as natural antioxidants in food systems

Sesame Lignans Suppress Age-Related Cognitive Decline in Senescence-Accelerated Mice

Sesame lignans, which are biologically active compounds present in sesame seeds and oil, are known to have neuroprotective effects in several models of brain dysfunction. However, the effects of sesame lignans on age-related brain dysfunction are not clear and were thus investigated in the present study using a senescence-accelerated mouse (SAMP10). Two-month-old male SAMP10 mice were administrated a basal diet with 0% or 0.05% sesame lignans for two months, or with 0%, 0.02%, or 0.05% sesame lignans for 10 months and subjected to step-through passive avoidance tasks and forced swim tests. Reactive carbonyl species (RCs) were evaluated as markers of oxidative stress using a recently developed comprehensive analytical method. Both learning time in passive avoidance tasks and immobile time in forced swim tests became longer with aging (p < 0.05). However, the administration of sesame lignans significantly ameliorated age-related effects in both tests (p < 0.05). Age-related increases in RCs such as 4-hydroxy-2-nonenal in the cerebral cortex and liver were reduced in mice fed sesame lignans. These results suggest that sesame lignans can prevent age-related brain dysfunction via anti-oxidative activity.

EFFECTIVE METHOD OF POLYPHENOL EXTRACTION FROM SESAME CAKE USING MICROBIAL FERMENTATION BY LACTOBACILLUS BREVIS NCTH24

Sesame seed is not only nutrient rich food but also of high polyphenol content. The total polyphenol content of Sesamum indicum’s bran can reach up to 150 mg/g. Among phenolic compounds, sesame lignans and anthocyanin were reported to have bioactive activities against diseases. The research focused on the development of method for sesame cake fermentation by Lactobacillus brevis NCTH24 to get high polyphenol content. It was found that fermentation medium of the following contents: 1/10 (w/v) ratio of sesame cake to distilled water, supplemented with 15g/l yeast extract and 1g/l glucose, adjusted to pH 6.0 then inoculated with 8% (v/v) inoculum of Lactobacillus brevis NCTH24 equivalent to 8.4*10^7 CFU/ml, to ferment at 30oC for 12h. As a result, the total polyphenol, flavonoid contents (calculated per gram dry sesame cake) and antioxidant activity through scavenged DPPH amount obtained from sesame cake fermented supernatant were 21.96 mg, 0.135 mg and 0.38 mg DPPH/30 min, respectively. They were significantly higher than those from sesame cake by extraction using methanol solvent (polyphenol 2.29 mg, flavonoid 0.05 mg and scavenged DPPH amount 0.19 mg/30 min).