56 RESEARCH PAPER SUSTAINABLE AQUATIC RESEARCH www.saquares.com Sustainable Aquatic Research, (2022) 1(2):56-62 DOI: 10.5281/zenodo.7033667 e-ISSN: 2822-4140 Abundance of heterotrophic marine bacteria, Vibrio, and marine fungi in green seaweed Caulerpa racemosa in Sibutu, Tawi-Tawi, Philippines Albaris B. Tahiluddin 1 * , Joan M. Daganio 1 , Rebecca S. Lodovice 1 , Mary Joy G. Umpay 1 1* College of Fisheries, Mindanao State University-Tawi-Tawi College of Technology and Oceanography, Bongao, Tawi-Tawi, 7500, Philippines. Citation Tahiluddin, A.B, Daganio, J.M., Lodovice, R.S., & Umpay, M.J.G. (2022). Abundance of Heterotrophic Marine Bacteria, Vibrio, and Marine Fungi in Green Seaweed Caulerpa racemosa in Sibutu, Tawi-Tawi, Philippines. Sustainable Aquatic Research, 1(2), 56-62. Artical History Received: 19 June 2022 Received in revised form: 4 August 2022 Accepted: 4 August 2022 Available online: 30 August 2022 Corresponding Author Albaris Tahiluddin E-mail: albarist20@gmail.com Tel: +639094260941 Keywords Caulerpa racemosa var. occidentalis Heterotrophic marine bacteria Marine fungi Vibrio Introduction Seaweeds are important coastal products that are commonly used as a food source (Delan et al., 2015), and they have been utilized in human diet for decades in Asia, and now also spreading rapidly in western countries (Løvdal et al., 2021). Caulerpa genus is a green seaweed, commonly called as “seagrapes,” popularly consumed in the 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 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 Tongehat, Sibutu, Tawi-Tawi is one of the sources of this seaweed. However, the microbial load of this green seaweed has not yet been explored and has remained unstudied. Hence, in this study, we determined the microbial load (colony-forming unit, CFU) of heterotrophic marine bacteria, Vibrio, and marine fungi from C. racemosa var. occidentalis in coastal waters of Tongehat, Sibutu, Tawi-Tawi, Philippines, following the serial dilution procedure. Results revealed that the heterotrophic 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 load 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.