Piengtawan Tappiban, Ph.D.

     With regards to postgraduate education, my research experiences were involved in genetic diversity of Krachaai Sayam and genes underlying cassava bacterial blight (CBB) disease.

     During working as a postdoc at Zhejiang University, I have intensively worked on the importance of starch branching enzymes (BEs) on starch fine structure and properties of indica rice. Based on the interspaced short palindromic repeats (CRISPR)/ associated protein-9 (Cas9) technology, five mutant lines including be1-1, be1-2, be2a-1, be2a-2 and be2b-1 were successfully generated, and the results showed that amylose content (AC) of be2b-1 (34.1%) was higher than that of wide type (WT) (27.4%) and the other mutants.
Mutations of either BEI or BEIIa did not affect the starch crystallite pattern (A-type), while mutation of BEIIb caused an opaque endosperm, the change of crystallite pattern from A- to B-type as well as an increase in the degree of ordered structure, the average chain length of amylopectin molecules and the gelatinization temperature. Moreover, down-regulation of BEI elevated the proportion of the shortest amylopectin chains (fa) but decreased the proportion of long amylopectin chains (fb2 and fb3). In conclusion, the relative importance of BEs in determining starch fine structure and properties of indica rice was in the order of BEIIb > BEI > BEIIa.

     Apart from the above mentioned, I also have focused on the studies of starch properties of native cassava starches. The key results found that cassava varieties and growth locations significantly affected the physicochemical properties and starch fine structure of cassava starches. Moreover, the effects of single and dual modifications through electron beam irradiation and hydroxypropylation of potato and corn starches have been completely investigated. Currently, I have a keen interest in starch modification of local starch resources for functional food applications by using diverse modification methods and its impacts on starch physicochemical properties and molecular fine structure.

1.Tappiban P, Zhao J, Zhang Y, Gao Y, Zhang L, Bao J. Effects of single and dual modifications through electron beam irradiation and hydroxypropylation on physicochemical properties of potato and corn starches. International Journal of Biological Macromolecules. 2022;220:1579-88.

2.Tappiban P, Hu Y, Deng J, Zhao J, Ying Y, Zhang Z, et al. Relative importance of branching enzyme isoforms in determining starch fine structure and physicochemical properties of indica rice. Plant Molecular Biology. 2022;108(4):399-412.

3.Tappiban P, Ying Y, Xu F, Bao J. Proteomics and Post-Translational Modifications of Starch Biosynthesis-Related Proteins in Developing Seeds of Rice. International Journal of Molecular Sciences. 2021; 22(11).

4.Tappiban P, Sraphet S, Srisawad N, Wu P, Han H, Smith DR, et al. Effects of cassava variety and growth location on starch fine structure and physicochemical properties. Food Hydrocolloids. 2020;108:106074.

5.Tappiban P, Ying Y, Pang Y, Sraphet S, Srisawad N, Smith DR, et al. Gelatinization, pasting and retrogradation properties and molecular fine structure of starches from seven cassava cultivars. International Journal of Biological Macromolecules. 2020;150:831-8.

• 2019-2022, Postdoctoral International Exchange Program; 2017-2018, UNESCO/People’s Republic of China (The Great Wall) Co-Sponsored Fellowships Programme 2017-2018