National Committee on Marine Sciences (NCMS)
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- In Silico supported nontarget analysis of contaminants of emerging concern: Increasing confidence in unknown identification in wastewater and surface watersAngeles, Luisa F.; Halwatura, Lahiruni M.; Antle, Jonathan P.; Simpson, Scott; Jaraula, Caroline M.B.; Aga, Diana S. (American Chemical Society, 2021-08-01)Nontarget analysis using liquid chromatography–high resolution mass spectrometry (LC–HRMS) is a valuable approach in characterizing for contaminants of emerging concern (CECs) in the environment. In this study, wastewater and surface water samples from three locations in Manila, Philippines were analyzed for CECs using a nontarget analysis approach with an LC-Orbitrap. A previously optimized semiautomated workflow was used for data processing with Compound Discoverer. A total of 157 compounds were identified, with 21 confirmed with reference standards, 83 confirmed with evidence from a mass spectral library (mzCloud), and 53 tentatively identified using in silico fragmentation (MetFrag). These compounds include pharmaceuticals such as antibiotics, antifungal, and antihypertensive compounds, human metabolites, natural products, pesticides, and industrial chemicals. Compounds confirmed with reference standards include antibiotics ciprofloxacin, clarithromycin, acetyl-sulfamethoxazole, and trimethoprim (2 to 19 ng/L), and antifungal compounds carbendazim and climbazole (3–47 ng/L). The pesticides diethyltoluamide (DEET) and diuron were also detected (37 ng/L). The utility of a preliminary multivariable linear regression quality structure-retention relationship (QSRR) model based on quantum chemical molecular descriptors is demonstrated. This study demonstrates the importance of using tools and software that are helpful for annotating HRMS data and reporting detections according to a standardized classification system. The detection of several CECs in wastewater and surface water samples show the importance of performing nontarget analysis in determining occurrence of CECs in the environment.We acknowledge support from the National Science Foundation PIRE-HEARD award number 1545756 and USAID PEER subaward number 2000009924. S.S. thanks the National Science Foundation (Award #1904825) for support of this research, and the Donors of the American Chemical Society Petroleum Research Fund (PRF-58954-UNI5). We also thank Shyrill Mae Mariano from the Marine Science Institute in the University of the Philippines − Diliman who helped with the sample collection and Rebecca Dickman from University at Buffalo for her help on technical work.
- Characterization of Alexandrium tamutum (Dinophyceae) isolated from Philippine waters, with the rare detection of paralytic shellfish toxinBenico, Garry; Azanza, Rhodora (Association of Systematic Biologists of the Philippines, 2022-04-01)Alexandrium tamutum M.Montressor, A.Beran & U.John is a non-toxic, bloom-forming dinoflagellate species commonly reported in temperate waters. In this study, 8 cultures of A. tamutum established from Bolinao Channel and Manila Bay, Philippines were characterized in terms of their morphology, phylogeny and toxicity. Cells were roundish, measuring 25.5 –29.84 µm long and 26.2–28.45 µm wide. The nucleus is equatorially elongated and located at the center of the cell. The chloroplasts are numerous, golden brown in color and radially arranged. Thecal tabulation is typical of Alexandrium: APC, 4', 6'', 6c, 6s, 5''', 2''''. Shape of the taxonomically informative thecal plates such as sixth precingular plate (6'') and posterior sulcal plate (sp) was similar to A. tamutum, which confirms the species identity. However, the presence of anterior and posterior attachment pores observed in our cultured isolates is the first case in this species. Molecular phylogeny inferred from LSU rDNA and ITS supports our identification by forming a well-supported clade composed of A. tamutum strains from other geographic regions. HPLC analysis showed that A. tamutum is generally non-toxic except for strain ATC9 which has low amount of decarbamoylsaxitoxin (dcSTX), resulting to a toxicity of 0.07 fmole STX eq per cell. The present study reports the first verified occurrence of Philippine A. tamutum with reliable morphological and molecular information, including the first record in Manila Bay and first detection of PST in one strain at a certain culture period.We acknowledge the Department of Science and Technology Philippine Council for Agriculture, Aquatic and Natural Resources Research and Development (DOST PCAARRD) and the University of the Philippines-The Marine Science Institute (UP-MSI) for the funding support. We are grateful for the assistance of Joshua Vacarizas, Keith Pinto and Jenelyn Mendoza for the molecular and toxicity analyses of the cultures. We also acknowledge Estrelita Flores, Emelita Eugenio and Jayson Orpeza for their assistance during the fieldwork and other logistical support.
- Fish farm effluents alter reef benthic assemblages and reduce coral settlementQuimpo, Timothy Joseph R.; Ligson, Charlon A.; Manogan, Dana P.; Requilme, Jeremiah Noelle; Albelda, Ritzelle L.; Conaco, Cecilia; Cabaitan, Patrick C. (Elsevier Ltd., 2020)Fish farming in coastal areas is a rapidly growing industry. However, unregulated fish farming practices that release massive amounts of unconsumed feed and fecal material into the water column, can result in a nutrient enriched environment that extends to nearby reef systems. To understand the impact of fish farm effluent on coral settlement, we tested the settlement rate of Pocillopora acuta larvae on artificial substrates conditioned for 12 weeks at three sites with increasing distance (2–10 km) from fish farms in Bolinao, Philippines. Sites far from the fish farms had higher biofilm and crustose coralline algae cover. In contrast, the site closest to the fish farms, where nutrient levels were higher, had greater sediment and turf algae cover. Tiles conditioned at the farther sites promoted higher (6–8%) larval settlement whereas tiles from the nearer site had lower settlement (3%). These findings show that fish farm effluents can indirectly affect coral settlement on adjacent reefs by promoting growth of other biota that may inhibit larval settlement and by reducing the availability of suitable substrate.
- Global mass spectrometric analysis reveals chemical diversity of secondary metabolites and 44-Methylgambierone production in Philippine Gambierdiscus strainsMalto, Zabrina Bernice L.; Benico, Garry A.; Batucan, Jeremiah D.; Dela Cruz, James; Romero, Marc Lawrence J.; Azanza, Rhodora V.; Salvador-Reyes, Lilibeth A. (Frontiers Media SA, 2022-02-04)Surveillance and characterization of emerging marine toxins and toxigenic dinoflagellates are warranted to evaluate their associated health risks. Here, we report the occurrence of the ciguatera poisoning-causative dinoflagellate Gambierdiscus balechii in the Philippines. Toxin production and chemical diversity of secondary metabolites in G. balechii GtoxSAM092414, G. balechii Gtox112513, and the recently reported Gambierdiscus carpenteri Gam1BOL080513 were assessed using targeted and untargeted UPLC-MS/MS analysis and radioligand receptor-binding assay (RBA). 44-methylgambierone was produced by all three strains, albeitwith different levels based on RBA and UPLC-HRMS/MS analysis. The fatty acid composition was similar in all strains, while subtle differences in monosaccharide content were observed, related to the collection site rather than the species. Molecular networking using the GNPS database identified 45 clusters belonging to at least ten compound classes, with terpene glycosides, carbohydrate conjugates, polyketides, and macrolides as major convergence points. Species-specific peptides and polyhydroxylated compounds were identified in G. balechii GtoxSAM092414 and G. carpenteri Gam1BOL080513, respectively. These provide a glimpse of the uncharacterized biosynthetic potential of benthic dinoflagellates and highlight the intricate and prolific machinery for secondary metabolites production in these organisms.We would like to thank H. Junio and the Secondary Metabolites Profiling Laboratory of the Institute of Chemistry, University of the Philippines Diliman and K. B. Davis for assistance in the conduct of this study.
- Potential of sediment bacterial communities from Manila Bay (Philippines) to degrade low-density polyethylene (LDPE)Gomez, Norchel Corcia F.; Onda, Deo Florence L. (Springer, 2022-12-24)The persistence of plastics and its effects in different environments where they accumulate, particularly in coastal areas, is of serious concern. These plastics exhibit signs of degradation, possibly mediated by microorganisms. In this study, we investigated the potential of sediment microbial communities from Manila Bay, Philippines, which has a severe plastics problem, to degrade low-density polyethylene (LDPE). Plastics in selected sites were quantified and sediment samples from sites with the lowest and highest plastic accumulation were collected. These sediments were then introduced and incubated with LDPE in vitro for a period of 91 days. Fourier transform infrared spectroscopy detected the appearance of carbonyl and vinyl products on the plastic surface, indicating structural surface modifications attributed to polymer degradation. Communities attached to the plastics were profiled using high-throughput sequencing of the V4-V5 region of the 16S rRNA gene. Members of the phylum Proteobacteria dominated the plastic surface throughout the experiment. Several bacterial taxa associated with hydrocarbon degradation were also enriched, with some taxa positively correlating with the biodegradation indices, suggesting potential active roles in the partial biodegradation of plastics. Other taxa were also present, which might be consuming by-products or providing nourishment for other groups, indicating synergy in utilizing the plastic as the main carbon source and creation of a microenvironment within the plastics biofilm. This study showed that sediment microbes from Manila Bay may have naturally occurring microbial groups potentially capable of partially degrading plastics, supporting previous studies that the biodegradation potential for plastics is ubiquitously present in marine microbial assemblages.We would like to acknowledge the Protected Area Management and Biodiversity Section of the Conservation and Development Division of the Department of Environment and Natural Resources—National Capital region for allowing us to conduct field work in LPPCHEA. As well as local government units of Brgy. Bucana in Ternate, Brgy. Bucana Malaki in Naic, Brgy. San Rafael III in Noveleta, and Brgy. Baseco in Manila for allowing us to conduct field work and sample collection. We would also like to acknowledge the Marine Research Center under the Marine Environmental Protection Command of the Philippine Coast Guard for providing assistance during one of our fieldworks. Members of the Microbial Oceanography Laboratory for helping during field works. And to Daniel John E. Purganan and Justine Marey S. Bitalac for helping us obtain CLS micrographs.
- Sea surface carbonate dynamics at reefs of Bolinao, Philippines: Seasonal variation and fish mariculture-induced forcingIsah, Raffi R.; Enochs, Ian C.; San Diego-McGlone, Maria Lourdes (Frontiers, 2022-11-11)Coral reefs are vulnerable to global ocean acidification (OA) and local human activities will continue to exacerbate coastal OA. In Bolinao, Philippines, intense unregulated fish mariculture has resulted in regional eutrophication. In order to examine the coastal acidification associated with this activity and the impact on nearby coral reefs, water quality and carbonate chemistry parameters were measured at three reef sites, a mariculture site and an offshore, minimally impacted control site during both the wet and dry season. Additionally, benthic community composition was characterized at reef sites, and both autonomous carbonate chemistry sampling and high-frequency pH measurements were used to characterize fine-scale (diel) temporal variability. Water quality was found to be poorer at all reefs during the wet season, when there was stronger outflow of waters from the mariculture area. Carbonate chemistry parameters differed significantly across the reef flat and between seasons, with more acidic conditions occurring during the dry season and increased primary production suppressing further acidification during the wet season. Significant relationships of both total alkalinity (TA) and dissolved inorganic carbon (DIC) with salinity across all stations may imply outflow of acidified water originating from the mariculture area where pH values as low as 7.78 were measured. This apparent mariculture-induced coastal acidification was likely due to organic matter respiration as sustained mariculture will continue to deliver organic matter. While TA-DIC vector diagrams indicate greater contribution of net primary production, net calcification potential in the nearest reef to mariculture area may already be diminished. The two farther reefs, characterized by higher coral cover, indicates healthier ecosystem functioning. Here we show that unregulated fish mariculture activities can lead to localized acidification and impact reef health. As these conditions at times approximate those projected to occur globally due to OA, our results may provide insight into reef persistence potential worldwide. These results also underscore the importance of coastal acidification and indicate that actions taken to mitigate OA on coral reefs should address not only global CO2 emissions but also local perturbations, in this case fish mariculture-induced eutrophication.This paper is part of the master’s thesis of RI supervised by MS-M entitled “Carbonate chemistry dynamics on the Bolinao reef flat”. The authors are grateful to the Marine Biogeochemistry Laboratory and Bolinao Marine Laboratory of the Marine Science Institute, University of the Philippines for the valuable logistical and laboratory support provided. We thank Jay Burce, Ryan Carl Magyaya, Natasha Tamayo for their tremendous help in field activities and laboratory analyses. We thank Alice Webb for providing insights into improving the manuscript.
- Attachment of potential cultivable primo-colonizing bacteria and its implications on the fate of low-density polyethylene (LDPE) plastics in the marine environmentBitalac, Justine Marey S.; Lantican, Nacita B.; Gomez, Norchel Corcia F.; Onda, Deo Florence L. (Elsevier, 2023-06-05)Plastics released in the environment become suitable matrices for microbial attachment and colonization. Plastics-associated microbial communities interact with each other and are metabolically distinct from the surrounding environment. However, pioneer colonizing species and their interaction with the plastic during initial colonization are less described. Marine sediment bacteria from sites in Manila Bay were isolated via a double selective enrichment method using sterilized low-density polyethylene (LDPE) sheets as the sole carbon source. Ten isolates were identified to belong to the genera Halomonas, Bacillus, Alteromonas, Photobacterium, and Aliishimia based on 16S rRNA gene phylogeny, and majority of the taxa found exhibit a surface-associated lifestyle. Isolates were then tested for their ability to colonize polyethylene (PE) through co-incubation with LDPE sheets for 60 days. Growth of colonies in crevices, formation of cell-shaped pits, and increased roughness of the surface indicate physical deterioration. Fourier-transform infrared (FT-IR) spectroscopy revealed significant changes in the functional groups and bond indices on LDPE sheets separately co-incubated with the isolates, demonstrating that different species potentially target different substrates of the photo-oxidized polymer backbone. Understanding the activity of primo-colonizing bacteria on the plastic surface can provide insights on the possible mechanisms used to make plastic more bioavailable for other species, and their implications on the fate of plastics in the marine environment.
- Moving towards open data, public access, and information sharing to combat marine plastics pollution in the Philippines and the Southeast Asian regionAlindayu, Ricardo C.; Licnachan, Lance Oliver C.; Luzadas, Ramgem L.; Ignacio, Paul Samuel P.; Onda, Deo Florence L. (Elsevier, 2023-09-01)Despite the consistent tagging of countries in Southeast Asia as among the top polluters of plastics in the oceans and the increasing local literature documenting the presence and abundance of plastics in marine environments, there still lacks a comprehensive, open, and accessible repository for marine plastics pollution data in the region. As such, this study presents the development of the PlastiCount Pilipinas portal in line with the call for a common data repository by the Philippines’ National Plan of Action for the Prevention, Reduction, and Management of Marine Litter and the ASEAN Regional Action Plan for Combating Marine Debris in the ASEAN Member States. A total of 14 existing databases were reviewed to identify key features for the online portal implemented to promote ease of access and diversified functionality. For the database, a total of 38 publications, 2 reports, 1 scientific poster, and 3 baselining studies were used to develop the initial ground-truthed baseline for marine plastic pollution, covering 23 provinces and 14 regions across the Philippines. The challenges presented by an observed variation across different methodologies and reporting styles emphasize the critical need to harmonize methods toward generating a more refined national baseline for marine litter. The initial baseline data and other resources such as manuals, information sheets, photographs, news, and publications are uploaded onto a public online portal for viewing and download (https://plasticount.ph/). Data and resource submissions from the public are also accepted and considered for inclusion in the database. The insights gained from developing the online portal and database for the Philippines can be used to inform the development of a regional database for Southeast Asia towards reducing marine litter.
- Assessing the efficiency of microplastics extraction methods for tropical beach sediments and matrix preparation for experimental controlsBonita, Jan Danielle P.; Gomez, Norchel Corcia F.; Onda, Deo Florence L. (Frontiers Media SA, 2023-11-03)Introduction: Microplastic pollution has become a global issue, eliciting attention not just from the scientific community but also both from the public and governmental bodies. Drawing data-driven policies and interventions, however, remain difficult due to the severely lacking baseline information from different environments such as beaches. One of the challenges in doing baseline studies is the lack of harmonized methodologies that will allow for comparison of results, integration of data, and its effective translation to evidence-based policies. Emphasis on quality control measures among baselining efforts through the proper implementation of experimental controls is also lacking. Methodology: To address these gaps, we compared methodologies for preparing the sediment matrix for experimental controls, as well as evaluated protocols for extracting microplastics from tropical beach sediments. Beach sediments were collected, dried, sieved, and spiked with known amounts of microplastics of different polymer types. The removal and extraction efficiencies of the protocols being compared were evaluated. Results and discussion: Our results showed that subjecting beach sediments to a furnace at 550° C for 4 hours is the most efficient way to remove plastic contamination, implying its applicability for preparing experimental controls. Meanwhile, a modified version of Masura et al. (2015), one of the widely cited methodologies for microplastics extraction, exhibited the highest mean extraction efficiency (99.05 ± 0.82%) among the protocols being compared. Results of this work will be useful in identifying methods that can be adopted and utilized for research and baselining efforts not just in the Philippines but also in Southeast Asia. This will also be helpful in the harmonization of methods, data reporting, and even skills as implemented through the regional and national action plans to address marine plastic pollution.The authors would like to thank the members of the Microbial Oceanography Laboratory of the University of the Philippines, The Marine Science Institute, especially Mark Prudente and Kim John Balboa who provided assistance during the conduct of the experiment, and the staff and administrative personnel of the Bolinao Marine Laboratory.