Aims: Electronic waste (e-waste) is an inorganic pollutant which causes a serious environmental problem since it contains toxic heavy metals, which cannot be removed from contaminated sites easily. The use of biomaterials for removing heavy metals from contaminated soil and wastewater has emerged as a potential alternative method to the conventional techniques. The present study were aimed to isolate efficient lead tolerant fungi from mangrove soil environment and measure its capability for lead removal from aqueous solution. Methodology and results: Lead tolerant fungal strains were isolated from soil samples using PDA (Potato Dextrose Agar) supplemented with varied concentrations of lead ions (100-500 mg/L). The most tolerant fungal strain was successfully isolated and identified molecularly as Fusarium equiseti KR706303. The isolated fungus was used for biosorption studies using Potato dextrose broth (PDB) supplemented with lead ions. The effects of pH, temperature, initial metal concentration, biomass dose and age, agitation and contact time to the Pb(II) removal efficiency were monitored in the study. The results showed that the optimal parameters for the removal of lead ions such as heavy metal concentration and pH were 300 mg/L, with a maximum Pb(II) adsorption of 97.9% observed at pH 4 and temperature of 30 °C during the batch biosorption experiments. The optimal parameters for biomass dose, agitation speed, contact time and biomass age were observed at 0.04 g, 150 rpm, 60 min and fifth day; respectively. Conclusion, significance and impact of study: The observation in this study revealed that the biomass of the isolated Fusarium equiseti KR706303 has the potential to be used as a biosorbent for heavy metal particularly Pb(II) removal from the contaminated sites. The technology is simple, efficient, cost effective and environmental friendly.
Electronic Waste ; Metals, Heavy ; Hazardous Waste

Aims: The oral cavity has the most complex microbiota after the stomach. A disturbed oral equilibrium can lead to the onset and development of periodontal disease. The known causative agents are the red complex bacteria (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola). This study was carried out to provide insights on the prevalence of periodontal pathogens in Sarawakian oral cavity since the data at present is still lacking. Methodology and results: A total of two millilitres (2 mL) of saliva samples were collected from twenty-seven (n=27) individuals (21 gingivitis, 6 healthy) between aged 18 until 30 years old, from Sarawak General Hospital. DNA extraction for the saliva samples was done by using phenol-chloroform method. Then, 16S rRNA PCR was performed followed by species-specific PCR for red complex bacteria detection. Statistical data was analysed using GraphPad Prism 8.4.1 software. As a result, 14% of gingivitis-affected female subjects were found with all the member of red complex species. Co-occurrence of red complex species was observed but no significant difference was found. An alarming presence of red complex bacteria particularly T. forsythia was detected in 57% of gingivitis subject as compared to the other red complex species. Conclusion, significance and impact of study The risk of acquiring periodontal disease increases by having at least one of the red complex species in the oral environment. Therefore, the rapid molecular detection of red complex bacteria in this study is useful for risk assessment of periodontal disease and proper species-targeted treatment to patients especially Sarawakian in general as the result has shed lights to the fairly poor oral status of volunteers.
Periodontal Diseases ; Saliva ; Mouth