Starch content kit

The content of total starch was determined by anthrone colorimetry using the starch content kit (Beijing Solarbio Science & Technology Co., Ltd., Beijing, China). The content of amylose was determined by iodine colorimetry using the amylose content kit (Beijing Solarbio Science & Technology Co., Ltd.). The content of amylopectin = the content of total starch-The content of amylose. Each sample was set for three biological replicates and SPSS software was used to statistical analysis.

Extraction of total starch and amylose content refers to the anthrone-sulfuric acid colorimetry method with slight modification [62 ]. The lotus rhizome samples stored in the refrigerator at −80 °C were ground thoroughly, and the powder obtained from each treatment was weighed into three parts, each part 0.03 g, to determine the total starch content of the lotus rhizome. The total starch content was determined by anthrone colorimetry using a starch content kit (Beijing Solarbio Science & Technology Co., Ltd., No. BC0700 Beijing, China). Lotus rhizome samples were fixed at 105 °C for 30 min, dried at 80 °C to constant weight, thoroughly ground the lotus rhizome sample and three servings weighed for each treatment, each part 0.01 g, and then used to determine amylose content. The content of amylose was determined by iodine colorimetry using an amylose content kit (Beijing Solarbio Science & Technology Co., Ltd., No. BC4260 Beijing, China). Amylopectin content = total starch content − amylose content.