Bacterial laminarinase for application in ethanol production from brown algae Sargassum sp. using halotolerant yeast

Document Type: Research Paper

Authors

1 Graduate School, University of the Philippines Los Banos, College, Laguna 4031, Philippines.

2 Hiroshima University, 739-0046 Hiroshima Prefecture, Higashihirosima, Kagamiyama, 1 Chome- 3- 2, Japan.

3 National Institute of Molecular Biology and Biotechnology (BIOTECH), University of the Philippines Los Banos, College, Laguna 4031, Philippines.

4 Institute of Biology College of Science, University of the Philippines Diliman, Quezon City, Philippines.

Abstract

Macroalgae are known to have many industrial applications, with current research targeting the potential of macroalgal biomass as feedstock in production of biofuels. Marine algal biomass is rich in storage carbohydrates, laminarin, and cellulose, which can be converted to fermentable sugars using appropriate enzymes, for fermentation to ethanol. This study focused on ethanol production from macroalgae using only enzymatic treatment for saccharification of algal biomass. This involved the isolation and identification of cellulase and laminarinase-producing microorganisms from mangrove area in the Philippines and production of partially purified enzymes for algal biomass saccharification. Results showed that the partially purified laminarinase produced from Bacillus sp. was capable of hydrolyzing the laminarin present in the macroalage. Fermentation of the algal hydrolysate yielded only small amount of ethanol due to lack of other pre-treatment methods, however, it was observed that higher ethanol was produced in saccharification treatments using a combination of cellulase and laminarinase which implies a possible synergistic effect between the two enzymes.

Graphical Abstract

Bacterial laminarinase for application in ethanol production from brown algae Sargassum sp. using halotolerant yeast

Highlights

  • Laminarinase enzyme was produced and partially purified from Bacillus sp.
  • Halotolerant yeasts were screened, partially characterized, and were later used in fermentation of saccharified algal biomass.
  • The laboratory-produced laminarinase was able to hydrolyze algal biomass to simple sugars, proving that it can be used for saccharification.
  • Ethanol produced in saccharification treatments using a combination of cellulase and laminarinase was higher implying a possible synergistic effect between the two enzymes.

Keywords


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