Spectrophotometric Method for the Determination of Dopamine Contents in Banana, Rhizome and Chinese Herbs

碩士 === 國立中興大學 === 食品科學系 === 93 === Dopamine is a kind of neurotransmitters which has important physiological functions. It’s a precursor for norepinephrine and can regulate the mood, behavior and movement. The purpose of this study is to investigate the spectrophotometric method for the determinatio...

Full description

Bibliographic Details
Main Authors: Ming-Fen Hong, 洪明芬
Other Authors: Yi-Chung Fu
Format: Others
Language:zh-TW
Published: 2005
Online Access:http://ndltd.ncl.edu.tw/handle/32642012478864251668
Description
Summary:碩士 === 國立中興大學 === 食品科學系 === 93 === Dopamine is a kind of neurotransmitters which has important physiological functions. It’s a precursor for norepinephrine and can regulate the mood, behavior and movement. The purpose of this study is to investigate the spectrophotometric method for the determination of dopamine through the charge-transfer reaction and establish the best condition of the experiment. The effects of various parameters, such as pH, temperature, reaction time and contents of the reagent were studied. The experiment showed that the complex of dopamine and chloranil in pH 6.0, 60℃ water bath with 5 mL reagents reacted for 60 minutes had maximum absorption at 465 nm. The standard curve showed that dopamine had good linear relationships in the range of 0.016 ~ 0.064 mg/mL. The correlation coefficient of the curve was 0.999. The relative standard deviation was 1.2% (n=10) 98% ~ 102% of the total amount of dopamine was recovered. The effects of different extraction methods in the food were also investigated. The food contained two kinds of banana (Formosana, AAA;Pei Chiao, AAA), rhizomes (yam, potato, sweet potato, and taro) and many kinds of Chinese herbal medicines. The experimental methods contained different concentrations of HCl, different temperature of extractions and different reagents of extractions. The contents of dopamine extracted from food: 100 ℃ ethanol > 100℃ water > normal room water temperature. Among of bananas, the highest content of dopamine was from Pei Chiao, AAA (北蕉) peels (61.84 mg/g);The contents of dopamine in mature-green bananas were higher than full mature and over mature bananas. The peels had higher contents of dopamine than pulp. Among of Chinese herbs: Ginkgo biloba L. (leaves) > Portuloca oleracea L. (leaves, whole plants, stems) > Angelicae sinensis Diels (當歸) > Glycyrrhizae uralensis Fisch (甘草) > Ligusticum chuanxiong Hort (川芎). Among the tubers of rhizomes, taro (芋頭) had the highest contents of dopamine (5.75 mg/g) and the potato had the lowest contents of dopamine (0.88 mg/g). Among the peels of rhizomes, the yam had the highest contents of dopamine (15.15 mg/g) and sweet potato(甘藷) had the lowest contents of dopamine (11.22 mg/g). The contents of dopamine in the peels in four kinds of rhizomes were higher than that in the tubers.