TY - JOUR
T1 - Biochemical responses of red alga Gracilaria corticata (Gracilariales, Rhodophyta) to salinity induced oxidative stress
AU - Kumar, Manoj
AU - Kumari, Puja
AU - Gupta, Vishal
AU - Reddy, C. R.K.
AU - Jha, Bhavanath
N1 - Funding Information: The financial support received from the Council of Scientific and Industrial Research (NWP 018), New Delhi is gratefully acknowledged. The authors are grateful to Dr. Dilip Ghosh, Director, Nutri Connect, Australia for scientific editing of the manuscript. The first author (MK) and second author (PK) gratefully acknowledges the CSIR, New Delhi for awarding the Senior and Junior Research Fellowships respectively. The third author (VG) also expresses his gratitude to Department of Science and Technology, New Delhi for financial support. We would also like to thank Mr. Harshad R. Brahmbhatt for technical assistance in analysis of fatty acids using GC-MS.
PY - 2010/8/1
Y1 - 2010/8/1
N2 - The biochemical responses of Gracilaria corticata (J. Agardh) J. Agardh to salinity induced oxidative stress were studied following the exposure to different salinities ranging from 15, 25, 35 (control), 45 to 55 in laboratory conditions. The growth was highest under 25 (3.14±0.69% DGR) and 35 (3.58±0.32% DGR) and decreased significantly in both extreme lower (15) and hyper (55) salinities. Both phycoerythrin (PE) and allophycocyanin (APC) were significantly higher in hyper-salinity (45) with an increase of almost 70% and 52% from their initial contents. Conversely, the level of increase of the same in hypo-salinities was considerably lower as compared with that of hyper-salinity. Both hypo- and hyper-salinity treatments induced almost two fold increase in the contents of polyphenols, proline and the activities of antioxidative enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) especially for 6d exposure. The Na+ ions readily displaced the K+ and Ca2+ from their uptake sites at extreme hyper-salinity (55) and accounted for substantial increase in the ratio of Na+/K+ and Na+/Ca2+ that impeded the growth under long term exposure (>6d). The survivability at salinity 45 even with considerably higher ratio of Na+/K+ and Na+/Ca2+ suggests the compartmentalization of Na+ into the vacuoles. Further, the micro nutrients such as Zn, Fe and Mn were decreased at both high and low end salinities with highest at extreme hyper-salinity. The C18:1(n-9) cis, C18:2(n-6), C18:3(n-3) and C20:4(n-6) were found in significant amounts in hyper-salinities. The C18:1(n-9) cis in particular increased by 60.25% and 70.51% for salinities 45 and 55, respectively from their initial amounts. The ratio of total unsaturated to saturated fatty acids (UFA/SFA) also increased linearly with increasing salinity. These results collectively suggest the potential role of antioxidative enzymes, phycobiliproteins, PUFAs and mineral nutrients to combat the salinity induced oxidative stress in G. corticata.
AB - The biochemical responses of Gracilaria corticata (J. Agardh) J. Agardh to salinity induced oxidative stress were studied following the exposure to different salinities ranging from 15, 25, 35 (control), 45 to 55 in laboratory conditions. The growth was highest under 25 (3.14±0.69% DGR) and 35 (3.58±0.32% DGR) and decreased significantly in both extreme lower (15) and hyper (55) salinities. Both phycoerythrin (PE) and allophycocyanin (APC) were significantly higher in hyper-salinity (45) with an increase of almost 70% and 52% from their initial contents. Conversely, the level of increase of the same in hypo-salinities was considerably lower as compared with that of hyper-salinity. Both hypo- and hyper-salinity treatments induced almost two fold increase in the contents of polyphenols, proline and the activities of antioxidative enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione reductase (GR) especially for 6d exposure. The Na+ ions readily displaced the K+ and Ca2+ from their uptake sites at extreme hyper-salinity (55) and accounted for substantial increase in the ratio of Na+/K+ and Na+/Ca2+ that impeded the growth under long term exposure (>6d). The survivability at salinity 45 even with considerably higher ratio of Na+/K+ and Na+/Ca2+ suggests the compartmentalization of Na+ into the vacuoles. Further, the micro nutrients such as Zn, Fe and Mn were decreased at both high and low end salinities with highest at extreme hyper-salinity. The C18:1(n-9) cis, C18:2(n-6), C18:3(n-3) and C20:4(n-6) were found in significant amounts in hyper-salinities. The C18:1(n-9) cis in particular increased by 60.25% and 70.51% for salinities 45 and 55, respectively from their initial amounts. The ratio of total unsaturated to saturated fatty acids (UFA/SFA) also increased linearly with increasing salinity. These results collectively suggest the potential role of antioxidative enzymes, phycobiliproteins, PUFAs and mineral nutrients to combat the salinity induced oxidative stress in G. corticata.
KW - Antioxidant enzymes
KW - Gracilaria corticata
KW - Minerals
KW - Oxidative stress
KW - Phycobiliproteins
KW - PUFAs
KW - Salinity stress
U2 - 10.1016/j.jembe.2010.06.001
DO - 10.1016/j.jembe.2010.06.001
M3 - Article
SN - 0022-0981
VL - 391
SP - 27
EP - 34
JO - Journal of Experimental Marine Biology and Ecology
JF - Journal of Experimental Marine Biology and Ecology
IS - 1-2
ER -