JJBS Volume 14, Number 5,December 2021 ISSN 1995-6673 Pages 945 – 951 https://doi.org/10.54319/jjbs/140510 Jordan Journal of Biological Sciences Utilization of “Uwi” Plant (Dioscorea sp.) as a Renewable Bioenergy Resource Wuryantoro Wuryantoro 1,* , Praptiningsih Gamawati Adinurani 1 , Ratna Mustika Wardhani 1 , Sutrisno Sutrisno 2 ,Bohari Mohammad Yamin 3 and Syukri Muhammad Nur 4,5 1 Department of Agrotechnology, Faculty of Agriculture, Merdeka University of Madiun, Jl. Serayu 79 Madiun 63133, Indonesia; 2 Department of Mechanical Engineering, Faculty of Engineering, Merdeka University of Madiun, Jl. Serayu 79 Madiun 63133, Indonesia; 3 Department of Chemistry, Faculty of Science and Technology, Kebangsaan University of Malaysia, 43600 UKM, 43600 Bangi, Selangor, Malaysia; 4 Graduate School of Renewable Energy, Darma Persada University, Jl. Radin Inten 2, Pondok Kelapa, East Jakarta 13450, Indonesia; 5 Center of Renewable Energy Studies, Darma Persada University, Jl. Radin Inten 2, Pondok Kelapa, East Jakarta 13450 Received: June, 11, 2021; Revised: Sep, 20, 2021; Accepted Oct, 16, 2021 Abstract Many countries are currently making efforts to obtain alternative energy to reduce dependence on fossil energy resources. “Uwi” plant is a carbohydrate source that has many types and is tolerant of being planted on the upland, so it has the potential to be used as a food crop and as bioenergy. This research aims to study the potential of varieties of “uwi” (Dioscorea sp.) as raw material for ethanol production. The eight varieties of “uwi” were studied to assess their ethanol potential. The selected raw materials are Dioscorea alata L. (white yam, purple yam, and yellow yam); Dioscorea esculenta (Lour.) Burkill (“uwi gembili” and “uwi gembolo"); Dioscorea bulbifera L. ("uwi gandul"); Dioscorea pentaphylla L. ("uwi katak") and Dioscorea hispida Dennst. (“uwi gadung"). A field experiment with Randomized Block Design was used to obtain homogenous tuber raw material, followed by laboratory methods on the assessment of ethanol production potential through fermentation. The research showed that the variety, D. hispida had the highest ethanol content (4.94 %), followed by D. esculenta (4.16 %) and D. alata (white yam) (3.89 %). The lowest ethanol production was obtained from D. pentaphylla (0.36 %) and D. bulbifera (1.53 %). However, in terms of productivity, D. alata (white-yam) is the most prospective considering its high production, ease of cultivation and tolerance of forest stands. Keywords: Alternative energy, Bioethanol, Clean energy, Diversity, Energy plant, Root tuber crop, Upland, Yam * Corresponding author e-mail: wuryantoro@unmer-madiun.ac.id. 1. Introduction Indonesia is the country with enormous energy consumption in Southeast Asia and fifth in the Asia Pacific, after China, India, Japan and South Korea. Increasing energy demand will increase along with the high average Gross Domestic Product (GDP) growth of 6.04 % during 2017 to 2050. Indonesia's final energy consumption (without firewood) in 2016 was still dominated by fuel oil at 47 % (Anindhita et al., 2018). The dependency on fuel is a problem because, in future time, it will run out and give emissions that harm the environment (Adinurani et al. 2017). The threat of scarcity of fossil energy has implications for an increase in the price of itself. On the other hand, Indonesia has great potential in producing renewable energy, one of which is biofuels (Adinurani et al, 2015; Tampubolon and Fauzi, 2016). Biofuels such as bioethanol are a form of fuel that will be dominant for the future because they are renewable (Adelabu et al. 2018). The production of renewable fuels, especially from starchy materials such as root crops, has great potential to meet future energy demand. The tuber group is a promising raw material for bioethanol because it has enough carbohydrates (16 % to 24 %), abundant availability and cost-effective proces- sing (Wuryantoro et al., 2020). Root crops are a better choice for bioethanol because they are cheap and less competitive as food than grains, only about 45 % of the tuber plant is consumed as food, and the rest is used for feed and industrial raw materials. ”Uwi” plant, ["uwi" is a common name in Indonesian, while in English it is called "yam" (Dioscorea sp.)] is a tuber group with lesser attention and has not received priority as a food source. This plant has many species and varieties, about 200 varieties with colours, shapes and flavours. Types of Dioscorea alata L., in particular, have colour variants and forms ranging from primary colours from white, yellow and purple, along with variations in shapes such as elongated, oblong, rounded, fingering to irregular (Wuryantoro et al., 2021). The existence of this plant is increasingly marginalized from cultivation techniques and is even allowed to grow wild. This group of tubers has excellent potential as a source of carbohydrates to use as raw material for bioethanol without disturbing food needs. “Uwi” plants are very suitable for planting in various land conditions,