Evaluation of Novel Probiotics Acting on Seaweed Biomass

Abstract: Fermentation is a technique which has been employed for the preservation of food since time immemorial. With a growing population comes the challenge of providing accessible and nutritious food and at the same time adapting a sustainable approach to achieve the desired target. Seaweeds have been utilized as food in the South-Southeast Asian cuisine for a long time in history. However, in the recent decades, seaweeds - typically green and brown seaweeds have found great scope as a sustainable food alternative in the European market. In this project, the ability to utilize novel lactic acid bacteria (KS1-4 and CW4) for the fermentation of seaweed A. esculenta was evaluated. Based on previous (unpublished) studies performed in the lab, it was found that the brown algae A. esculenta contain 9.16 ± 0.17 % DW of mannitol and 5.67 ± 0.07 % DW of glucose making them interesting substrates to be used for the cultivation of lactic acid bacteria. In this study, it was seen that Lactobacillus strains KS1-4 and CW4 are able to ferment the seaweed A. esculenta by utilizing the substrates mannitol and glucose innately present in the seaweed. The effect of heat-treatment on the seaweed and its consequent effect on the fermentation efficiency was analyzed. It was found that irrespective of the method of treatment employed, the novel probiotic strains were able to grow and ferment the seaweed. Thereby highlighting their ability to downregulate the growth of other bacteria in addition to preventing the growth of spoilage micro-organisms like fungi. Utilizing potential probiotic strains for the fermentation of seaweeds not only enhances their nutritional properties and helps in improving their storage faculties, but also helps to enhance the sensory properties of the intended food product. Analyzing the results obtained from this study indicated that the lactobacillus strain KS1-4 closely resembled Lactiplantibacillus plantarum and CW4 closely resembled Levilactobacillus brevis.