The Effects of Green Light-emitting Diodes (LED) and Nitrogen on Photo-physiological Index and Antioxidative Functions of Hydroponically Grown Limnophila (Limnophila rugosa (Roth) Merr.)

• Main Authors: Yen-Chieh Chiang, 江彥潔
• Other Authors: Chao-Ti Hsiung
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/23184793909672679225

碩士 === 國立臺北教育大學 === 自然科學教育學系碩士班 === 101 === According to recent studies, light quality influences the concentrations of many secondary metabolites in plants. Cell damage by oxidation is a critical determinant in the process of many clinical diseases and aging, thus the medical community has begun to value research on free radicals and antioxidants. Limnophila rugosa (Roth) Merr originated from central and southern China, Taiwan, and Vietnam. The population grows in Calla lilly fields, provides health benefits, and is a native merr with great potential for development. My research uses Limnophila rugosa (Roth) Merr as research material, providing different levels of LED green light in hydroponic culture. In order to understand the effect of different levels of green LED light on antioxidant activity, we analyze the appearance traits, photo-physiological index, the ability to clear DPPH free radicals, the ability to chelate ferrous, and measurements of antioxidant properties such as reduction power of Limnophila rugosa (Roth) Merr. The photochemical reflectance index (PRI) is significantly different in groups treated with green light (P<0.01): the group not treated with green light, the BR group is the most highly significant, followed by the BRg group, and the BRG group was the lowest; nitrogen fertilizer made no significant difference. SPAD showed a significant difference with green light treatment and nitrogen fertilizer treatment (P<0.05): with green light treatment, the BR group was highest, followed by the BR group, and the BRG group was the lowest; with nitrogen fertilizer treatment, 0.5X is significantly higher than 0.1X and 1X. Chlorophyll fluorescence QI shows a significant difference with green light treatment (P<0.01): green light treatment produced the highest significance in the BR group, followed by the BRg group, and BRG group is lowest; nitrogen fertilizer treatment made a significant difference (P<0.05): 0.5X is significantly higher than 0.1X and 1X. Analysis of antioxidant power of alcohol extract from Limnophila rugosa (Roth) Merr showed that using strong nitrogen fertilizer and green light produce an increasing trend on clearance of DPPH free radicals, the ability to chelate ferrous, and the reduction power of BHT. The results from this study can provide insight for medical health and agriculture in the future.