Isolation of a Prebiotic-Producing Gene (1-SST) in Dioscorea esculenta (Gembili) using Primers Designed from Chromosome 11 of Dioscorea rotundata

Abstract

Inulin is a group of heterogeneous polysaccharides which is used in food industry as a soluble-fiber prebiotic with an estimate global market value reaching USD 1.5 million by 2023. Further, the low-calorie and gut health-enhancing properties increase the demand for Inulin. In order to meet the demand in Indonesia, the conventional extraction method from plants that are not available in Indonesia should be replaced; An Indigenous plant, Dioscorea esculenta (Gembili) is known to produce a considerable amount of Inulin. Through genetic engineering, the Inulin yield from Gembili can be improved. Even more, the gene responsible, 1-SST and 1-FFT, can be incorporated into yeasts or microbial cells to reduce the reliance on plant-based raw material. This study isolates 1-SST gene which is the first gene in the metabolic pathway of Inulin production. To do this, primers were adapted and designed from literature as well as the whole genome sequence (WGS) of Dioscorea rotundtata; which is the only WGS available for Dioscorea spp. These primers were then used to isolate the sequence fragments from genomic DNA of Dioscorea esculenta. With the utilization of matK gene, the plant sample used in this study was confirmed as Dioscorea esculenta. Further, result from one of the self-designed primers (11A) shows that the isolated sequence was related to Invertase and 1-SST. However, another self-designed primers (11B), isolated a calcium-dependent protein kinase. Lastly, 2DC primers adapted from literature could not isolate any sequence in this study. Several considerations are needed in the future study.