Infrared Spectrum and Thermodynamic Studies of Catechin-Black Rice Anthocyanin Complex
XIANG Ying1, FENG An-di2, ZHAO Zheng-zhuo1, SUN Cong-dan1, XU Hao-peng1, SUN Li-na1, XIE Feng-ying1, 3*
1. College of Food Science, Northeast Agricultural University, Harbin 150030, China
2. College of Resources and Environment, Northeast Agricultural University, Harbin 150030, China
3. Harbin Food Industry Research Institute, Harbin 150028, China
Abstract：Catechin-black rice anthocyanin complex was chemically synthesized by black rice anthocyanin using acetaldehyde-mediated. The reaction mechanism of catechin - black rice anthocyanin complex was determined by infrared spectrum and thermodynamic parameters. The results showed that the catechin-black rice anthocyanin complex had a wide and strong absorption peak of —OH stretching vibration region at 3 207.90 and 3 217.90 cm-1, and appeared the benzene ring skeleton vibration absorption peak at C═C stretching vibration region around 1 604.92 and 1 605.65 cm-1. The infrared absorption peaks appeared at 1 278.01, 1 138.34 and 1 018.19 cm-1 in the 1 300~1 000 cm-1 C═O telescopic vibration region. It can be concluded the catechin-black rice anthocyanin complex and black rice anthocyanin had basically same structure framework with the main structure of aromatic ring structure —OH, C═C and C═O substituted groups. Compared with black rice anthocyanin, of catechin-black rice anthocyanin complex had the absorption peak not only at 1 604.92 and 1 493.59 cm-1, but also at 1 454.78, 1 233.98 and 817.56 cm-1. Based on absorption peak assignment, it was found that the absorption peak at 1 454.78 cm-1 belonged to —CH3 antisymmetric deformation or —CH2 deformation vibration band, which proved the existence of “ethyl bridge” in catechin-black rice anthocyanin complex. It was confirmed that there was condensation reaction between catechin and black rice anthocyanin. The appearance of absorption peaks of 817.56 and 1 233.98 cm-1 indicated that the plane valence bonds of some groups bent after the condensation reaction between catechin and black rice anthocyanin, which increased the polarity of CO bond. In addition, the results of thermodynamic parameters showed that the condensation reaction between catechin and black rice anthocyanin was endothermic and non-spontaneous, and the structure of catechin-the black beige complex was stable.
[1] Yousuf B, Gul K, Wani A, et al. Critical Reviews in Food Science and Nutrition, 2016, 56(13): 2223.
[2] Cardona F, Cristina Andrés-Lacueva, Tulipani S, et al. The Journal of Nutritional Biochemistry, 2013, 24(8): 1415.
[3] ZUO Dan, LIAO Xia, LI Yao, et al(左 丹, 廖 霞, 李 瑶, 等). Food Science(食品科学), 2017, 38(7): 266.
[4] Cardona F, Cristina Andrés-Lacueva, Tulipani S, et al. The Journal of Nutritional Biochemistry, 2013, 24(8): 1415.
[5] HE Jing-ren, KUANG Min-jie, QI Min-yu, et al(何静仁，邝敏杰，齐敏玉，等). Food Science(食品科学)，2015，36(7)：228.
[6] Sheridan M K, Elias R J. Food Chemistry, 2015, 177: 17.
[7] XIE Feng-ying, LI Feng-feng, ZHANG Shuang, et al(谢凤英, 李凤凤, 张 爽, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2018, 38(8): 2386.
[8] Hao J, Zhu H, Zhang Z, et al. Journal of Cereal Science, 2015, 64: 92.
[9] Jampani C, Naik A, Raghavarao K S M S. Separation and Purification Technology, 2014, 125: 170.
[10] LI En-hui, JIAO Xin-yao, WANG Chen-ge, et al(李恩惠, 矫馨瑶, 王晨歌, 等). Food Science(食品科学), 2018, 39(5): 1.
[11] Basalekou M, Pappas C, Tarantilis P, et al. International Journal of Food Science & Technology, 2017, 52(6): 1307.
[12] Caramês Elem T S, Alamar Priscila D, Poppi Ronei J, et al. Food Analytical Methods, 2017, 10(5): 1609.
[13] Snyder A B, Sweeney C F, Rodriguez-Saona L E, et al. Food Chemistry, 2014, 147(6): 295.
[14] Swer T L, Chauhan K. Lebensmittel-Wissenschaft und-Technologie/Food Science and Technology, 2019, 102: 181.
[15] Chanphai P, Tajmir-Riahi H A. Food Hydrocolloids, 2019, 89: 461.
