TY - JOUR
T1 - Structure-activity relationship of Citrus segment membrane RG-I pectin against Galectin-3
T2 - The galactan is not the only important factor
AU - Wu, Dongmei
AU - Zheng, Jiaqi
AU - Hu, Weiwei
AU - Zheng, Xiaoliang
AU - He, Qiaojun
AU - Linhardt, Robert J.
AU - Ye, Xingqian
AU - Chen, Shiguo
N1 - Publisher Copyright:
© 2020
PY - 2020/10/1
Y1 - 2020/10/1
N2 - Rhamnogalacturonan I (RG-I) pectin are regarded as strong galectin-3 (Gal-3) antagonist because of galactan sidechains. The present study focused on discussing the effects of more structural regions in pectin on the anti-Gal-3 activity. The water-soluble pectin (WSP) recovered from citrus canning processing water was categorized as RG-I pectin. The controlled enzymatic hydrolysis was employed to sequentially remove the α-1,5-arabinan, homogalaturonan and β-1,4-galactan in WSP. The Gal-3-binding affinity KD (kd/ka) of WSP and debranched pectins were calculated to be 0.32 μM, 0.48 μM, 0.56 μM and 1.93 μM. Moreover, based on the more sensitive cell line (MCF-7) model, the IC30 value of WSP was lower than these of modified pectins, indicating decreased anti-Gal-3 activity. Our results suggested that the total amount of neutral sugar sidechains, the length of arabinan and cooperation between HG and RG-I played important roles in the anti-Gal-3 activity of WSP, not the Gal/Ara ratio or RG-I/HG ratio. These results provided a new insight into structure-activity relationship of citrus segment membrane RG-I as a galectin-3 antagonist and a new functional food.
AB - Rhamnogalacturonan I (RG-I) pectin are regarded as strong galectin-3 (Gal-3) antagonist because of galactan sidechains. The present study focused on discussing the effects of more structural regions in pectin on the anti-Gal-3 activity. The water-soluble pectin (WSP) recovered from citrus canning processing water was categorized as RG-I pectin. The controlled enzymatic hydrolysis was employed to sequentially remove the α-1,5-arabinan, homogalaturonan and β-1,4-galactan in WSP. The Gal-3-binding affinity KD (kd/ka) of WSP and debranched pectins were calculated to be 0.32 μM, 0.48 μM, 0.56 μM and 1.93 μM. Moreover, based on the more sensitive cell line (MCF-7) model, the IC30 value of WSP was lower than these of modified pectins, indicating decreased anti-Gal-3 activity. Our results suggested that the total amount of neutral sugar sidechains, the length of arabinan and cooperation between HG and RG-I played important roles in the anti-Gal-3 activity of WSP, not the Gal/Ara ratio or RG-I/HG ratio. These results provided a new insight into structure-activity relationship of citrus segment membrane RG-I as a galectin-3 antagonist and a new functional food.
KW - Carbohydrate active enzymes
KW - Citrus segment membrane
KW - Galectin-3 inhibitor
KW - Polysaccharide
KW - RG-I regions
KW - SEC-MALLS
UR - http://www.scopus.com/inward/record.url?scp=85086303022&partnerID=8YFLogxK
U2 - 10.1016/j.carbpol.2020.116526
DO - 10.1016/j.carbpol.2020.116526
M3 - Article
C2 - 32718630
AN - SCOPUS:85086303022
SN - 0144-8617
VL - 245
JO - Carbohydrate Polymers
JF - Carbohydrate Polymers
M1 - 116526
ER -