Effects of degradation on the physicochemical and antioxidant properties of carboxymethyl pachymaran

Zhaoxi Chen; Yalin Zhao; Xi Feng; Lijia Zhang; Salam A Ibrahim; Wen Huang; Ying Liu

doi:10.1016/j.ijbiomac.2023.125560

Effects of degradation on the physicochemical and antioxidant properties of carboxymethyl pachymaran

Int J Biol Macromol. 2023 Aug 1:245:125560. doi: 10.1016/j.ijbiomac.2023.125560. Epub 2023 Jun 24.

Authors

Zhaoxi Chen¹, Yalin Zhao¹, Xi Feng², Lijia Zhang¹, Salam A Ibrahim³, Wen Huang¹, Ying Liu⁴

Affiliations

¹ College of Food Science and Technology, Huazhong Agricultural University, Key Laboratory of Environment Correlative Dietology, Ministry of Education, Wuhan, Hubei 430070, China.
² Department of Nutrition, Food Science and Packaging, San Jose State University, San Jose, CA 95192, United States.
³ Department of Family and Consumer Sciences, North Carolina A&T State University, 171 Carver Hall, Greensboro, NC 27411, United States.
⁴ College of Food Science and Technology, Huazhong Agricultural University, Key Laboratory of Environment Correlative Dietology, Ministry of Education, Wuhan, Hubei 430070, China. Electronic address: yingliu@mail.hzau.edu.cn.

PMID: 37364805
DOI: 10.1016/j.ijbiomac.2023.125560

Abstract

Poria cocos (Schw.) Wolf is a well-known edible and medicinal fungus. The polysaccharide in the sclerotium of P. cocos was extracted and prepared into carboxymethyl pachymaran (CMP). Three different degradation treatments including high temperature (HT), high pressure (HP) and gamma irradiation (GI) were used to process CMP. The changes in physicochemical properties and antioxidant activities of CMP were then comparatively investigated. We found that the molecular weights of HT-CMP, HP-CMP, and GI-CMP decreased from 787.9 kDa to 429.8, 569.5 and 6.0 kDa, respectively. Degradation treatments had no effect on the main chains of →3-β-D-Glcp-(1 → while changed the branched sugar residues. The polysaccharide chains of CMP were depolymerized after high pressure and gamma irradiation treatments. The three degradation methods improved the stability of CMP solution while decreased the thermal stability of CMP. In addition, we found that the GI-CMP with lowest molecular weight had the best antioxidant activity. Our results suggest that gamma irradiation treatment could degrade CMP as functional foods with strong antioxidant activity.

Keywords: Aggregation state; Antioxidant activity; Carboxymethyl pachymaran; Chemical structure; Molecular size; Physical treatment.