Phytoplankton and Bacterial Communities in South Harbour, Manila Bay, Philippines

Abstract

In line with the ASEAN-India project “Extent of Transfer of Alien Invasive Organisms in South/Southeast Asia via Shipping”, phytoplankton and bacterial communities in the waters off South Harbour, Manila Bay were investigated. Sampling was done in July and August 2012 and in April and May 2013. A total of 67 phytoplankton species including 29 diatoms and 38 dinoflagellates were identified. Potentially toxic Pseudo-nitzschia spp. were among the diatoms found as well as dinoflagellates Alexandrium spp., and Gymnodinium spp. The diatom Skeletonema costatum appeared to be the dominant species in July and August 2012, whereas Chaetoceros spp. constituted over 85% of the total phytoplankton assemblage in April and May 2013. Mean bacterialabundance ranged from 9.53 x 102–3.18 x 105 cells/mL in July 2012. In addition, 93 bacterial isolates were identified using 16S rDNA, several of which belonged to the following phyla: Actinobacteria, Bacteriodetes, Firmicutes, and Proteobacteria; whereas, others were determined as uncultured bacterial clones. These results will serve as a valuable baseline for future studies on phytoplankton and bacterial community structure in Manila Bay.

Application of Fluorescence in situ hybridization-Flow cytometry (FISH-FCM) technique to detect and quantify Vibrio cholerae population from different geographic regions

“…Nutrients and suspended particulate matter are important factors in determining the bacterial abundance in a coastal environment (Khandeparker et al 2017a). Azanza et al (2018) isolated a total of 93 bacteria from the surface and bottom waters of South Harbour, Manila Bay of Philippines. A total of 64 isolates were representatives from four bacterial phyla: Actinobacteria (22%), Bacteriodetes (1%), Firmicutes (12%), and Proteobacteria (34%).…”

“…A total of 64 isolates were representatives from four bacterial phyla: Actinobacteria (22%), Bacteriodetes (1%), Firmicutes (12%), and Proteobacteria (34%). Three isolates identified were reported as pathogenic bacteria, namely: Gordonia bronchialis, Kytococcus sedentarius, and Microbacterium oleivorans (Azanza et al 2018). G. bronchialis is a human pathogen associated with pulmonary disease (Tsukamura 1971), K. sedentarius is considered as an opportunistic pathogen that causes valve endocarditis, hemorrhagic pneumonia and pitted keratolysis (Sims et al 2009) and M. oleivorans is known to cause bacteremia (Kim and Lee 2012).…”