Journal of Environmental Microbiology and Toxicology

Propagation and Feasibility Study of Pennisetum purpureum for Removal of Arsenic in Constructed Wetland

2024-04-05T08:11:41+08:00

Various species of plants have recently been identified as hyperaccumulators, capable of storing and resisting high concentrations of toxic metals. A perfect hyperaccumulator for phytoremediation must exhibit rapid growth and produce significant biomass. In the case of P. purpureum, roots displayed a growth rate of 1.19 cm/day, stems 4.78 cm/day, with an absolute growth rate (AGR) peaking at 4.16 ± 0.091 gm/day after 77 days. Regression analysis (y = 0.138x, R2 = 0.9904) revealed a strong correlation between dry and wet weights. Water content in P. purpureum ranged from 70.59 ± 1.27% to 85.54 ± 1.54%. Typically propagated from seeds, P. purpureum is known for its ease of cultivation, rapid growth, and simple seed collection for subsequent generations. At 77 and 105 days, respective calorific values for the whole plant were 19,888 ± 238.66 J/g and 18,405 ± 220.86 J/g, indicating potential bioenergy use post-phytoremediation. This study comprehensively examines the physical growth, growth rate, biomass, water content, and calorific value of P. purpureum, revealing its robust root system and rapid growth characteristics. Thus, P. purpureum emerges as a promising candidate for heavy metal uptake in environmental remediation efforts.

Exposure and Toxicity of Polybrominated Diphenyl Ethers: A Mini Review

2023-12-30T04:03:54+08:00

Polybrominated Diphenyl Ethers (PBDEs), recognized as persistent organic pollutants by the United Nations Environment Programme, are a class of brominated flame retardants that pose significant environmental and health risks. These compounds, consisting of two aromatic rings with up to 10 bromine atom substitutions, are categorized into penta-BDE, octa-BDE, and deca-BDE based on their bromine content, each exhibiting distinct environmental behaviors. PBDEs with fewer bromine atoms are more volatile and prone to bioaccumulation, raising significant health concerns. These compounds, often added physically to products, can leach into the environment, leading to pollution during production and after the parent polymer degrades. The transformation of higher brominated diphenyl ethers into less brominated forms in the environment further complicates their impact, with mono-brominated BDE-3 being particularly concerning due to its extended atmospheric photolysis lifetime and increased bioavailability. The management of PBDEs is challenging due to their persistence and transformation in the environment. As endocrine disruptors, they are linked to various acute and chronic toxicological effects, including neurodevelopmental toxicity, teratogenicity, and potential carcinogenicity. Their structural similarity to thyroid hormones allows them to disrupt thyroid hormone balance, leading to further health complications. The subject of this review is to summarize the current body of knowledge that is essential to understand their long-term effects on ecosystems and human health and to develop strategies to mitigate their adverse impacts.

Growth and Storage Study of Streptococcus agalactiae as a Potential Target in Whole-Cell Based ‘Systematic Evolution of Ligands by Exponential Enrichment (SELEX)’ Procedure

2024-01-04T07:57:58+08:00

Streptococcus agalactiae is a pathobiont that causes severe invasive infections, especially in fishponds or freshwater aquatic organisms. Streptococcus outbreak in cultured fishponds causes a negative impact on the production of fishes, especially tilapias. Therefore, it is essential to develop a reliable method for on-site monitoring of S. agalactiae in fishponds. This study aims to investigate a local S. agalactiae strain TP540K as a potential target for DNA aptamer in a whole-cell based ‘systematic evolution of ligands by exponential enrichment (SELEX)’ procedure. Before this procedure, the bacterial growth profile of S. agalactiae strain TP540K was studied. Besides, the viability of S. agalactiae strain TP540K was compared between different storage solutions (glycerol, phosphate buffer saline, distilled water) and temperatures (-20, 4 and 27 °C). In this study, S. agalactiae strain TP540K entered the log phase at 1.5 h of incubation time, thus the cells were collected at 2 h of incubation time with an OD₆₀₀ value of 0.436 to proceed to SELEX process. Moreover, glycerol stock (20%, -20 °C) was the best storage condition for preservation of S. agalactiae strain TP540K until Day 84 with a cell viability of 2.48 x 10⁷ CFU/mL. With the findings obtained, S. agalactiae strain TP540K could be utilised as a target for future study in DNA aptamer development through whole-cell based SELEX procedure, which could be useful for future investigations to overcome Streptococcus outbreak in the Malaysian aquaculture industry.