Antioxidant capacity and carbon-based scope for growth of brackish water clams Corbicula japonica under the combined effects of natural and anthropogenic factors

Preeti Pokhrel; Sayaka Mashiko; Shumona Akther; Jumpei Suzuki; Masafumi Fujita

doi:10.1016/j.envpol.2022.119676

Antioxidant capacity and carbon-based scope for growth of brackish water clams Corbicula japonica under the combined effects of natural and anthropogenic factors

Environ Pollut. 2022 Sep 1:308:119676. doi: 10.1016/j.envpol.2022.119676. Epub 2022 Jun 23.

Authors

Preeti Pokhrel¹, Sayaka Mashiko¹, Shumona Akther¹, Jumpei Suzuki², Masafumi Fujita³

Affiliations

¹ Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki, 316-8511, Japan.
² Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Chiba, 270-1194, Japan.
³ Global and Local Environment Co-creation Institute, Ibaraki University, Hitachi, Ibaraki, 316-8511, Japan. Electronic address: masafumi.fujita.wenv@vc.ibaraki.ac.jp.

PMID: 35753544
DOI: 10.1016/j.envpol.2022.119676

Abstract

Changes in natural estuarine environment and anthropogenic disturbances are becoming significant threats to organisms, particularly bivalves. A deeper understanding of the relationship between biochemical- and individual-level responses is necessary to assess the combined effects of natural and anthropogenic factors on bivalves. To the best of our knowledge, this is the first study where the oxygen radical absorbance capacity (ORAC) and carbon-based scope for growth (C-SFG) were applied as biomarkers to evaluate the response of the brackish water clam Corbicula japonica to four spatiotemporally varying environmental factors. High water temperature and food availability supported C-SFG while high salinity inhibited it. Most of wastewater (WW) treatments resulted in negative C-SFG values because of a reduced clearance rate and increased excretion rate. In particular, high food availability with WW treatment resulted in the lowest C-SFG value of -114 μg C·ind^-1 h^-1. The ORAC was activated in response to high salinity with WW treatment (p < 0.05). To ascertain the combined effects of the natural and anthropogenic factors, principal component and cluster analyses were performed on the ORAC and C-SFG data. Anthropogenic WW was found to have different effects on the physiological and biochemical biomarkers according to the natural conditions. A roughly negative correlation was observed between ORAC and C-SFG because activation of the antioxidant capacity can influence the growth potential of the clams through the additional use of available metabolic energy. However, some exceptions were observed where both the ORAC and C-SFG values were either high or low, which could be because the C-SFG response varies depending on different metabolic behaviors even when the ORAC response remains the same. These results indicate that the biochemical-level response (i.e., ORAC) of C. japonica can be interpreted using individual-level response (i.e., C-SFG), but careful attention must be given to over- or underestimation.

Keywords: Biomarkers; Food availability; Salinity; Wastewater; Water temperature.

MeSH terms

Animals
Anthropogenic Effects
Antioxidants / metabolism
Carbon / metabolism
Corbicula* / metabolism
Saline Waters

Substances

Antioxidants
Carbon