Abundance of Heterotrophic Marine Bacteria, Vibrio, and Marine Fungi in Green Seaweed Caulerpa racemosa in Sibutu, Tawi-Tawi, Philippines

Abstract

Seaweeds have been used in the human diet for centuries, particularly in Asia. Green seaweed from the genus of Caulerpa is consumed throughout the Pacific and Southeast Asia, with high economic value. In the Philippines, Caulerpa spp. are one of the the seaweed delicacies among locals eaten as salads. In Tawi-Tawi, southern Philippines, Caulerpa racemosa var. occidentalis is one of the edible seaweeds which is sold in the market center in Bongao, Tawi-Tawi, and is sourced from Tongehat, Sibutu, Tawi-Tawi. However, the microbial abundance of this green seaweed has not yet been explored and has remained unstudied. Hence, in this study, we determined the microbial abundance (colony-forming unit, CFU) of marine bacteria, Vibrio, and marine fungi from C. racemosa var. occidentalis in coastal water of Tongehat, Sibutu, Tawi-Tawi, Philippines, following serial dilution procedure. Results revealed that the marine bacteria recorded the highest abundance of 5.9 x 10¹⁰ CFU g^-1. Vibrio abundance was 1.2 x 10² CFU g^-1, and marine fungi abundance was 4.1 x 10³ CFU g^-1. The low presence of Vibrio in this study indicates that the C. racemosa var. occidentalis contains low potential pathogens and may be safe for human consumption.