Sesame (Sesamum indicum L.) is a plant that belongs to the Pedaliaceae family which was first classified as a food source around 4000 years ago. Lignans (sesamin, sesamolin, sesamol, and sesaminol) present in sesame are the primary functional compounds that impart important health benefits. However, very little information is available on the lignan intake from sesame seeds and sesame oil products. Sesame oil is frequently and highly consumed in Korea and therefore is one of the important lignan intake sources due to the food eating habits of Koreans. Herein, we studied the distribution of lignans in sesame seeds (n = 21) and oil (n = 34) to estimate the daily lignan intake by the Korean population. High-performance liquid chromatography, in conjunction with statistical analysis, was used to determine the lignan content of seeds and oil. The estimated daily intake of total lignans from sesame seeds and oil, as estimated from the available domestic consumption data (Korea Nutrition and Health Examination Survey), is 18.39 mg/person/day for males and 13.26 mg/person/day for females. The contributions of lignan intake from sesame seeds and oil are 23.0% and 77.0%, respectively. This study provides preliminary information on lignan intake from sesame seeds and oil in the Korean population.
Dioscorea batatas Decne (Chinese yam) has been widely cultivated in East Asia for the purposes of food and medicinal uses for centuries. Along with its high nutritional value, the medicinal value of D. batatas has been extensively investigated in association with phytochemicals such as allantoin, flavonoids, saponins and phenanthrenes. Phenanthrenes are especially considered the standard marker chemicals of the Chinese yam for their potent bioactivity and availability of analysis with conventional high performance liquid chromatography with ultraviolet detection (HPLC-UV) methods. In order to investigate how much the contents of phenanthrenes are in the actual food products provided for consumers, D. batatas tuber was peeled and separated into its peel and flesh as in the conventional processing method. A quantitative analysis using the HPLC-UV method revealed that phenanthrenes are concentrically present in the D. batatas peel, while phenanthrenes are present in the flesh under the limit of detection. The difference in the contents of phenanthrenes is estimated to have arisen the considerable difference of antioxidant potential between the peel and the flesh. The results from this study suggest the high value of the discarded biomass of the Chinese yam peel and the necessity for the utilization of the Chinese yam peel.