Optimisation of Antarctic filamentous alga growth in the presence of molybdenum

• Main Authors: Verasoundarapandian, Gayathiri, Wong, Chiew Chan, Lim, Zheng Syuen, Mohd Zahri, Khadijah Nabilah, Darham, Syazani, Zakaria, Nur Nadhirah, Ahmad, Siti Aqlima
• Format: Article
• Published: Malaysian Society for Biochemistry and Molecular Biology 2023
• Online Access: http://psasir.upm.edu.my/id/eprint/110517/; https://1f169227-0328-4af2-99bc-24934f131be8.filesusr.com/ugd/66925b_a75aea1d05504fd8b108feb32edb6344.pdf

Elevated concentrations of heavy metals have been identified in Antarctica due to growing anthropogenic activities in recent years. Molybdenum (Mo) is a trace element that has not been extensively studied in terms of its toxicity towards the environment, especially in extremely cold weather. The algae communities in the Antarctic were less focused and explored, unlike indigenous bacteria consortia in their response to heavy metals. The study aims to optimise the physicochemical conditions for optimal growth of an Antarctic algal, Klebsormidium sp. in the presence of Mo via conventional one‒ factor‒at‒a‒time (OFAT) and growth kinetics analysis. Algal cultures with aeration showed a higher growth rate (µ = 0.2352 d-1 ) than those without aeration (µ = 0.1976 d-1 ). Based on the optimised parameter, the overall biomass yields with and without aeration systems correspond to each other (P > 0.05). It was discovered that the Klebsormidium sp. showed maximal growth in terms of biomass at 20 g/L of sucrose, 2 g/L of ammonium nitrate, 4 g/L NaCl concentration and pH 7.5. The overall optimised conditions were further analysed using the Exponential growth model, which demonstrated no significant difference (P > 0.05) in the algae growth rate with aeration (0.020 ± 0.0018 h-1 ) and without aeration (0.020 ± 0.0015 h-1 ). The Antarctic filamentous algae exhibited the ability to grow in heavy metal, Mo at optimal growth conditions, but the aeration systems did not affect the algae growth significantly. Therefore, this study could help in understanding the capability of algae to grow in the presence of heavy metal through various manipulations of growth parameters and act as a preliminary study for bioremediation of Mo in Antarctic polluted sites.