The effect of salinity on phenolics biosynthesis and antioxidant activity in germinated sesame

• Main Authors: Tsai-Ju Lee, 李采如
• Other Authors: E-Mean Chiu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/42474913033763051710

碩士 === 國立宜蘭大學 === 食品科學系碩士班 === 100 === In this study sesame seed was soaked with different salt stress for 9 hours, fllowed by 1—6 day germination in dark, germination percentage, seedling length and composition of seedling were observed, and the variation of phenolics and antioxidant activity were also analysis in the period of germination. The results showed that the germination percentage of sesame under 0.9M NaCl pretreatment was 75.9%, that was the highest in all systems. The systems of RO and 0.3M NaCl had higher seedling length of 3.47 and 3.63 cm respectively. The analysis of proximate composition showed that there was no significant difference on the content of ash and crude protein in all systems. The ash content in all systems were between 4.43—5.79%, the protein contents were between 18.39—22.57%, althought the content of crude protein showed a little bit higher unter 0.3M and 0.9M salt treatmeats. When compare the change of crude lipid and carbohydrate of sesame seedling in the period of germination, the content of the crude lipids 37.04—56.37% decreased while carbohydrates 16.39—37.63% were increase proportionally. Higher carbohydrate content and lower lipid content were observed in the systems with salt stress than that of RO. The change of total phenols in sesame seedlings showed that total phenolic content of sesame seedling under 0.9M NaCl pretreatment were highest, 1.5M NaCl treatments is next, but there was no significant increased in the system of 0.3M NaCl. Total phenolic content of sesame oil under 0.9M salt pretreatment at 6th days were highest, but the others didn’t have significantly. When evaluate the change of antioxidation capacity of sesame during germination, the chelating power was 76.86% first day and the reducing power was 117.58 mg ascorbic acid / g MeOH extract 5th day had the best antioxidative activity. The free radical scavenging activity and ORAC of sesame seedlings were 87.48% and 4280.13μmole TE / g MeOH extract sepectively for 1.5M system had the highest activity. For the change of antioxidation capacity of sesame oil in the period of germination, 0.9M NaCl system had the highest free radical scavenging activity 63.90% and ORAC 524.00μmole TE / g MeOH extract respectively at 2th and 6th day. 1.5M salt treatment of germination sesame oil at 4th day had the best reducing power, 61.48 mg ascorbic acid / g MeOH extract, and 0.3M treatment at 4th day of sesame oil had the best chelating power 32.90%. Keyword: sesame, salt, stress, phenolics