Al3+ and Fe2+ toxicity reduction potential by acid-resistant strains of Rhodopseudomonas palustris isolated from acid sulfate soils under acidic conditions
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This research aimed to evaluate the capacity of acid-resistant purple nonsulfur bacteria, Rhodopseudomonas palustris strains VNW02, TLS06, VNW64, and VNS89, to resist Al3+ and Fe2+ and to investigate their potential to remove both metals from aqueous solutions using exopolymeric substances (EPS) and biomasses. Based on median inhibition concentration (IC50), strain VNW64 was the most resistant to both metals under conditions of aerobic dark and microaerobic light; however, strain TLS06 was more resistant to Al3+ under aerobic dark conditions. High metal concentrations resulted in an altered cellular morphology, particularly for strain TLS06. Metal accumulation in all tested PNSB under both incubating conditions as individual Al3+ or Fe2+ was in the order of cell wall > cytoplasm > cell membrane. This was also found in a mixed metal set only under conditions of aerobic dark as microaerobic light was in the degree of cytoplasm > cell wall > cell membrane. Of all strains tested, EPS from strain VNW64 had the lowest carbohydrate and the highest protein contents. Metal biosorption under both incubating conditions, EPS produced by strains VNW64 and TLS06, achieved greater removal (80 mg Al3+ L−1 and/or 300 mg Fe2+ L−1) than their biomasses. Additionally, strain VNW64 had a higher removal efficiency compared to strain TLS06. Based on the alteration in cellular morphology, including biosorption and bioaccumulation mechanisms, R. palustris strains VNW64 and TLS06 demonstrated their resistance to metal toxicity. Hence, they may have great potential for ameliorating the toxicity of Al3+ and Fe2+ in acid sulfate soils for rice cultivation.
KeywordsBioaccumulation Biopolymer Bioremediation Biosorption Paddy field Purple nonsulfur bacteria
The first author was totally supported by the Graduate School, Prince of Songkla University from Thailand’s Education Hub for Southern Region of ASEAN Countries (TEH-AC), grant number TEH-AC 027/2015 that made possible this study.
- Attanandana T, Vacharotayan S (1986) Acid sulfate soils: their characteristics, genesis, amelioration and utilization. Southeast Asian Stud 24:155–180Google Scholar
- Ilamathi R, Nirmala GS, Muruganandam L (2014) Heavy metals biosorption in liquid solid fluidized bed by immobilized consortia in alginate beads. Int J Chem Tech Res 6:652–662Google Scholar
- Johnson JL (1981) In: Gerhardt P, RGE M, Costilow RN, Nester EW, Wood WA, Krieg NR, Phillips GB (eds) Manual of methods for general bacteriology. American Society for Microbiology, Washington, DC 20006, p 456Google Scholar
- Khuong NQ, Kantachote D, Onthong J, Sukhoom A (2017) The potential of acid-resistant purple nonsulfur bacteria isolated from acid sulfate soils for reducing toxicity of Al3+ and Fe2+ using biosorption for agricultural application. Biocatal Agric Biotechnol 12:329–340Google Scholar
- Panhwar QA, Naher UA, Shamshuddin J, Radziah O, Hakeem KR (2016) Management of acid sulfate soils for sustainable rice cultivation in Malaysia. In: Hakeem K, Akhtar J, Sabir M (eds) Soil science: agricultural and environmental prospectives. Springer International Publishing, Cham, pp 91–104CrossRefGoogle Scholar
- Panwichian S, Kantachote D, Wittayaweerasak B, Mallavarapu M (2011) Removal of heavy metals by exopolymeric substances produced by resistant purple nonsulfur bacteria isolated from contaminated shrimp ponds. Electron J Biotechnol 14(4):2–2Google Scholar
- Samaranayake P, Peiris BD, Dssanayake S (2012) Effect of excessive ferrous (Fe2+) on growth and iron content in rice (Oryza sativa). Int J Agric Biol 14:296–298Google Scholar
- Soltanpour PN, Johnson GW, Workman SM, Jones JB, Miller RO (1996) Inductively coupled plasma emission spectrometry and inductively coupled plasma-mass spectrometry. In: Sparks DL, Page AL, Helmke PA, Loeppert RH (ed.) Methods of soil analysis. Part 3—chemical methods. SSSA Book Ser. 5.3. SSSA, ASA, Madison, WI. doi: https://doi.org/10.2136/sssabookser5.3. Pp 91-139
- Swanner ED, Bayer T, Wu W, Hao L, Obst M, Sundman A, Byrne JM, Michel FM, Kleinhanns IC, Kappler A, Schoenberg R (2017) Iron isotope fractionation during Fe (II) oxidation mediated by the oxygen-producing marine cyanobacterium Synechococcus PCC 7002. Environ Sci Technol 51(9):4897–4906CrossRefPubMedPubMedCentralGoogle Scholar
- Wurl O, Miller L, Vagle S (2011) Production and fate of transparent exopolymer particles in the ocean. J Geophys Res 116(C7):C00H13Google Scholar