Cherrie Teh, C.P.1,2*, Daphne Ling, H.A.1, Nithiyaa, N.1 and Aileen Tan, S. H.1
1Marine Science Lab, School of Biological Sciences, Universiti Sains Malaysia, 11700 Minden, Penang
2Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia
The carbon dioxide (CO2) emitted to the atmosphere by human activities is absorbed by the oceans and consequently causes not only an increase in partial pressure of CO2 (pCO2) but also a decrease in seawater pH. The alteration of pH in seawater has significant effects on calcifying invertebrates. To date, most of the studies were concentrated on the impact of ocean acidification on the shell formation and growth of oysters but not on the biochemical components.
This study compared the biochemical components (total carbohydrate, total protein and total lipid) of the tropical oyster, Crassostrea belcheri at two culture sites. The first site is located at Pulau Betong, Penang Island, which is an open sea culture with normal seawater condition (pH: 8.0 ± 0.2; salinity: 31.4 ± 0.1 ppt) and the other site is located at Merbok, Kedah which is a river estuarine with lower pH (pH: 7.3 ± 0.1) and salinity (salinity: 22.3 ± 0.7).
The C. belcheri from Pulau Betong showed significantly higher biochemical content (total carbohydrate: 6.79 ± 1.10%, total protein: 20.65 ± 3.38% and total lipid: 3.88 ± 2.29%) compared to C. belcheri from Sungai Merbok (total carbohydrate: 5.04 ± 0.93%, total protein: 17.39 ± 3.72% and total lipid: 2.68 ± 1.94%). The storage and the utilization of biochemical components of the oysters were observed to be different at different culture sites.
Overall, the study revealed the impact of ocean acidification on biochemical components of the tropical oysters and this can provide information on the nutritional and edible values of the oysters to the consumers and also to ensure the food safety and security.