Microbes from Brine Systems with Fluctuating Salinity Can Thrive under Simulated Martian Chemical Conditions

The waters that were present on early Mars may have been habitable. Characterising environments analogous to these waters and investigating the viability of their microbes under simulated martian chemical conditions is key to developing hypotheses on this habitability and potential biosignature formation. In this study, we examined the viability of microbes from the Anderton Brine Springs (United Kingdom) under simulated martian chemistries designed to simulate the chemical conditions of water that may have existed during the Hesperian. Associated changes in the fluid chemistries were also tested using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The tested Hesperian fluid chemistries were shown to be habitable, supporting the growth of all of the Anderton Brine Spring isolates. However, inter and intra-generic variation was observed both in the ability of the isolates to tolerate more concentrated fluids and in their impact on the fluid chemistry. Therefore, whilst this study shows microbes from fluctuating brines can survive and grow in simulated martian water chemistry, further investigations are required to further define the potential habitability under past martian conditions.

Investigation of Heavy Metal Accumulation in Mung Bean through Inductively Coupled Plasma Optical Emission Spectroscopy

Vigina radiata (Mung bean) is an important legume species belongs to the family Fabaceae, cultivated in varies region of Ethiopia for its nutritional values. The nutritional composition of the crop affected by different biotic and environmental stress which depends on growth environment. The aim of the present study was to determine the concentrations of selected heavy metals (Pb, Cu and Cr) in seed of mung bean collected from Shewarobit, Northcentral Ethiopia using inductively coupled plasma optical emission spectroscopy (ICP-OES). Acid digestion with HCl, HNO3 and HClO4 for 1hr at temperature of 90oC to 95oC by hot plate digester. The level of the heavy metals in the samples were 2.51 mg/L, Pb; 6.53 mg/L, Cu; and 0.38 mg/L, Cr respectively. The concentration of copper (Cu) in the seed of mung bean was higher than the other target metals (Pb and Cr) whereas, Cr occurred in least concentration. The overall accuracy of the method obtained from spiking experiment (recovery) was within the range 80 to 120%, which accounts 115.75%, 97.5%, 101.17% for Pb Cr and Cu respectively. Notably, these results indicating the reliability and applicability of the procedure for extraction of studied metals. The concentration of heavy metals in edible seed of mungbean is low as compared to WHO/FAO recommendation and absolutely safe for consumption in the study area. Thus, producer should follow similar agroecological managements of the crop production to maintain heavy metal concentration of such in the crop.