https://doi.org/10.17113/ftb.63.01.25.8583

article in press

A Novel Glucomannan Extraction Method Using Aqueous Two-Phase System

Enny Sholichah^1,2, Bambang Purwono^1*, Agnes Murdiati³, Akhmad Syoufian¹, Nok Afifah² and Achmat Sarifudin²

¹Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Jl. Sekip Utara, Bulaksumur, Yogyakarta, Indonesia

²Research Center for Appropriate Technology, National Research and Innovation Agency Jl. KS. Tubun No. 5 Subang, West Java, Indonesia

³Department of Food and Agriculture Product Technology, Faculty of Agriculture Technology Universitas Gadjah Mada, Jl. Flora No.1 Bulak sumur, Yogyakarta, Indonesia

Copyright © 2024 This is a Diamond Open Access article published under CC-BY licence. Copyright remains with the authors, who grant third parties the unrestricted right to use, copy, distribute and reproduce the article as long as the original author(s) and source are acknowledged.

Article history:

Received: 7 February 2024

Accepted: 8 December 2024

Keywords:

aqueous two-phase system (ATPS), glucomannan, Na₂HPO₄, K₂HPO₄, porang

Summary:

Research background. Glucomannan is a polysaccharide compound used widely in food and pharmacies industries. Tuber of Amorpophallus muelleri Blume is called as porang in Indonesia. Ethanol extraction system is commonly used to extract glucomannan from porang flour, however, the method still shows some limitations. Glucomannan obtained from ethanol extraction method contains protein higher than which of the standard glucomannan. The current research explored the salting-out effect of salts of aqueous two-phase system for glucomannan extraction process. Therefore, protein can be removed from glucomannan flour enhancing the purity of the obtained glucomannan.

Experimental approach. A novel glucomannan extraction method using aqueous two-phase system (ATPS) which consisted of salt and ethanol was investigated. The salts of Na₂HPO₄ and K₂HPO₄ solution in 3 different concentration levels (1, 2 and 3 %), mixed with 40 % ethanol with 1:1 ratio, were used to compose ATPS. The performance of ATPS method on glucomannan extraction was observed based on the phase separation and the characteristics of glucomannan including proximate, color, thermal properties and surface morphology of glucomannan. The statistical analysis was performed to test the significant differences between the mean value of each treatment. The statistical significance level (P) was set at 0.05.

Results and conclusions. Results indicated that ATPS showed an ability to separate porang flour in solution into 3 parts namely bottom (F1), middle (F2) and top (F3) parts. The bottom (F1) and middle (F2) parts were rich of glucomannan and starch, respectively while the top part consisted of ethanol-soluble compound. Salts impacted the yield of glucomannan and the characteristics of the obtained glucomannan including the color, impurities (protein and ash) content, thermal properties, molecular mass and surface morphology. The increasing salt concentration reduced the yield of glucomannan but increased the yield of the other components. ATPS reduced the protein content and increased the lightness of glucomannan. Glucomannan obtained from ATPS showed higher thermal stability than the control.

Novelty and scientific contribution. Salting-out effect of salt of ATPS is commonly used in protein precipitation and isolation. However, there was no report found on the implementation of ATPS for glucomannan isolation. This study showed that ATPS method (Na₂HPO₄/ethanol and K₂HPO₄/ethanol) is a potential novel extraction method to be implemented in glucomannan extraction process.