TY  - JOUR
AU  - Fu, Jingjing 
AU  - Xiao, Haifang 
AU  - Yu, Shaoxuan 
AU  - Wu, Han 
AU  - Berenjian, Aydin 
AU  - Song, Yuanda 
PY  - 2017
TI  - Response Surface Optimized Ultrasonic Assisted Extraction of Total Flavonoids from Walnut Leaves and In Vitro Antibacterial Activities
JF  - American Journal of Biochemistry and Biotechnology
VL  - 13
IS  - 4
DO  - 10.3844/ajbbsp.2017.176.188
UR  - https://thescipub.com/abstract/ajbbsp.2017.176.188
AB  - In this paper, the optimum extraction conditions of total flavonoids extracted from walnut leaves subjected to Ultrasonic Assisted Extraction (UAE) were optimized by Response Surface Methodology (RSM). The mathematical model showed the high coefficient of measurement (R2 = 0.9938) which indicated that this model could be used to guide the response surface methodology. The optimum extraction parameters for extracting flavonoids from walnut leaves determined in this study were extraction temperature 47.73°C, extraction time 30.79 min, ethanol concentration 72.89% (v/v). Under the optimal extraction conditions, the flavonoids yield was about 3.5315%. Statistical analysis of the results showed that extraction temperature, extraction time and ethanol concentration significantly affected the extraction yield of total flavonoids. In addition, the antibacterial activity assays of the flavonoids were carried out and it was demonstrated that the total flavonoids extracted at the optimum conditions had pronounced antibacterial effects against the four bacterial species. Therefore, this study suggested that walnut leaves are promising resources with antibacterial properties for the development of phytomedicines.