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In this study, we explored the ability of wild-Serbian Ganoderma lucidum mycelial pellets (GLMPs) in treating synthetic domestic wastewater in a batch reactor under various operating conditions. The GLMPs produce non-hazardous by-products, are environmentally sustainable and able to produce in mass bulk with consistent quality. Riding on the highly efficient of treatment of industrial (textile) wastewater using GLMPs, similar high efficiency is foreseen for domestic wastewater as a green alternative treatment process. The optimal performance of GLMPs in similar synthetic domestic wastewater with a Carbon-to-Nitrogen (C/N) ratio of 16.7:1 was evaluated under three operational conditions. The C/N ratio was chosen based on the urban domestic wastewater characteristic during high peak flow with an initial Chemical Oxygen Demand (COD) of 533 mg/L and ammonia–nitrogen (NH3–N) content of 30 mg/L. The operational parameters of agitation speed (0 rpm, 25 rpm, 50 rpm, and 100 rpm), environmental temperature (25 °C, 30 °C, 35 °C, and 40 °C), and GLMP inoculum percentage (GIP) (0%, 0.25%, 0.50%, 0.75%, and 1.00%) were chosen for the experiment. In the experiment, the agitation speed of 100 rpm and the environmental temperature of 25 °C showed the best performance of the GLMPs within 15 h of retention time with a percentage removal of 92.9% for COD and 93.8% for NH3–N. Furthermore, a high volume of GIP in the batch reactor had an insignificant impact on the performance in the same concentration of wastewater, and 0.25% GIP was the volume used to treat the domestic wastewater.

Sewage treatment plants (STP) in Malaysia are designed to treat a load of contaminants according to the level of concentration for chemical oxygen demand (COD) and nitrogen ammonia (NH3-N) of 250 mg/L and 30 mg/L, respectively. However, studies show that the organic load of Malaysian wastewater is low and even temporarily fluctuates resulting in the low effectiveness of treatment especially in ammonia removal and consequently cause effluents that do not undergo proper treatment to be released into the environment. Therefore, this study aims to identify concentrations of COD and NH3-N in the influent of urban domestic wastewater along with other physico-chemical characteristics. Two locations of the STP were chosen based on the urban area with different catchment sizes for a population equivalent (PE) 60,000 for the first STP (LRK#1), and 150,000 for the second STP (LRK#2). These parameters include pH, temperature, conductivity, turbidity, total suspended solids (TSS), nitrogen nitrate (NO3-N), total Kjeldahl nitrogen (TKN) as well as heavy metals such as Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn). The sampling and analysis methods used the guidelines recommended in the American Public Health Association (APHA). The results give the highest average COD concentrations for the LRK#1 and LRK#2 are 180.5 mg/L and 380.9 mg/L, respectively. The highest NH3-N concentrations were 33.53 mg/L for LRK#1 and 31.63 mg/L for LRK#2. Overall, the wastewater physico-chemical characteristics of both treatment plants show wastewater in the medium and low concentration categories.

The fluctuation of domestic wastewater characteristic inhibits the current conventional microbial-based treatment. The bioremediation fungi has received attention and reported to be an effective alternative to treat industrial wastewater. Similar efficient performance is envisaged for domestic wastewater whereby assessed performance of fungi for varying carbon-to-nitrogen ratios in domestic wastewater is crucial. Thus, the performance of pre-grown wild-Serbian Ganoderma lucidum mycelial pellets (GLMPs) was evaluated on four different synthetic domestic wastewaters under different conditions of initial pH (pH 4, 5, and 7) and chemical oxygen demand (COD) to nitrogen (COD/N) ratio of 3.6:1, 7.1:1, 14.2:1, and 17.8:1 (C3.6N1, C7.1N1, C14.2N1, and C17.8N1). The COD/N ratios with a constant concentration of ammonia–nitrogen (NH3–N) were chosen on the basis of the urban domestic wastewater characteristics sampled at the inlet basin of a sewage treatment plant (STP). The parameters of pH, COD, and NH3–N were measured periodically during the experiment. The wild-Serbian GLMPs efficiently removed the pollutants from the synthetic sewage. The COD/N ratio of C17.8N1 wastewater had the best COD and NH3–N removal, as compared to the lower COD/N ratio, and the shortest treatment time was obtained in an acidic environment at pH 4. The highest percentage for COD and NH3–N removal achieved was 96.0% and 93.2%, respectively. The results proved that the mycelium of GLMP has high potential in treating domestic wastewater, particularly at high organic content as a naturally sustainable bioremediation system.

The fungi-based technology, wild-Serbian Ganoderma lucidum (WSGL) as myco-alternative to existing conventional microbial-based wastewater treatment is introduced in this study as a potential alternative treatment. The mycoremediation is highly persistent for its capability to oxidatively breakdown pollutant substrates and widely researched for its medicinal properties. Utilizing the non-hazardous properties and high degradation performance of WSGL, this research aims to find optimum conditions and model the mycoremediation treatment design for Chemical Oxygen Demand (COD) and Ammonia Nitrogen (AN) removal in domestic wastewater via response surface methodology (RSM). Combined process variables were temperature (⁰C) (Model 1) and the volume of mycelial pellets (%) (Model 2) against treatment time (hour). Response variables for these two sets of central composite design (CCD) were the removal efficiencies of COD (%) and AN (%). The regression line fitted well with the data with R2 values of 0.9840 (Model 1-COD), 0.9477 (Model 1-AN), 0.9988 (Model 2-COD) and 0.9990 (Model 2-AN). The lack of fit test gives the highest value of Sum of Squares equal to 9494.91 (Model 1- COD), 9701.68 (Model 1-AN), 23786.55 (Model 2-COD) and 13357.02 (Model 2-AN), with probability F values less than 0.05 showing significant models. The optimum conditions were established corresponding to the percentage of COD and AN removal obtained were 95.1% and 96.3%, accordingly at the optimum temperature 25°C at the treatment time of 24 h, meanwhile 0.25% of mycelial pellet with 76.0% and 78.4% COD and AN removal, respectively. The high performance achieved demonstrates that the mycoremediation of G. lucidum is highly potential as part of the wastewater treatment system in treating domestic wastewater of high organic loadings.

The fungi-based technology, wild-Serbian Ganoderma lucidum (WSGL) as myco-alternative to existing conventional microbial-based wastewater treatment is introduced in this study as a potential alternative treatment. The mycoremediation is highly persistent for its capability to oxidatively breakdown pollutant substrates and widely researched for its medicinal properties. Utilizing the nonhazardous properties and high degradation performance of WSGL, this research aims to optimize mycoremediation treatment design for chemical oxygen demand (COD) and ammonia nitrogen (AN) removal in domestic wastewater based on proposed Model 1 (temperature and treatment time) and Model 2 (volume of pellet and treatment time) via response surface methodology (RSM). Combined process variables were temperature (0C) (Model 1) and the volume of mycelial pellets (%) (Model 2) against treatment time (hour). Response variables for these two sets of central composite design (CCD) were the removal efficiencies of COD (%) and AN (%). The regression line fitted well with the data with R2 values of 0.9840 (Model 1-COD), 0.9477 (Model 1-AN), 0.9988 (Model 2-COD), and 0.9990 (Model 2-AN). The lack of fit test gives the highest value of sum of squares equal to 9494.91 (Model 1-COD), 9701.68 (Model 1-AN), 23786.55 (Model 2-COD), and 13357.02 (Model 2-AN), with probability F values less than 0.05 showing significant models. The optimized temperature for Model 1 was at 25 °C within 24 h of treatment time with 95.1% COD and 96.3% AN removals. The optimized condition (temperature) in Model 1 was further studied in Model 2. The optimized volume of pellet for Model 2 was 0.25% in 24-h treatment time with 76.0% COD and 78.4% AN removals. Overall, the ascended sequence of high volume of pellet considered in Model 2 will slow down the degradation process. The best fit volume of pellet with maximum degradation of COD and AN is equivalent to 0.1% at 25 °C in 24 h. The high performance achieved demonstrates that the mycoremediation of G. lucidum is highly potential as part of the wastewater treatment system in treating domestic wastewater of high organic loadings.

The efficiency of the wastewater treatment is highly influenced by the characteristics of incoming raw wastewater into the treatment plant. The improper design resulted in inefficient treatment, of which consequently leading to the pollution and contaminant release to nearby water streams. High concentration of untreated or inefficiently treated effluent poses significant impacts to the health of both human and aquatic life. Wastewater characteristics based on real-time monitoring measurement in a catchment area, in particular at the inlet chamber of a sewage treatment plant (STP) not only provides precise data and information of pollutant loading behavior but also hypothesis the lifestyle and waste habit in the specific locations. In this research, the parameters of Chemical Oxygen Demand (COD) and Ammonia Nitrogen (NH3-N) incoming raw wastewater samples were temporally monitored. The measurement campaign was conducted at two locations, at a Network Pumping Station (NPS) and connected STP with Population Equivalent (PE) of 1000 and 60000, respectively. The temporal variation for COD shows a regular pattern with distinct peaks, i.e., at morning and evening were identified. However, no temporal variation was observed for parameter NH3-N. The strength of the wastewater influent has a fairly low concentration of COD between 57 mg/L to 313 mg/L at NPS and 117 mg/L to 612 mg/L at STP. This value is lower than the commonly influent designed STP of COD concentration at 500 mg/L (Malaysian Sewerage Industry Guidelines (MSIG), Volume IV, Section 3). Comparison of wastewater pattern with temperate climate of South Korea showed a discrepancy in terms of peak time and concentration pattern.