Oxidative enzymes from newly local strain Aspergillus iizukae EAN605 using pumpkin peels as a production substrate: Optimized production, characterization, application and techno-economic analysis.

The present study deals with optimizing, producing, characterizing, application and techno- economic analysis of oxidative enzymes [Laccase (Lac), manganese peroxidase (MnP), and lignin peroxidase (LiP)] from Aspergillus iizukae EAN605 in submerged fermentation process using pumpkin peels as a production substrate. The best operating parameters for producing Lac, MnP and LiP (6.15, 2.58 and 127.99 U mg-1 respectively) were recorded with 20 g 100 mL-1 of substrate, 4.6 mL 100 mL-1 of inoculum size at pH 5.5 after 10 days. The crude enzyme exhibited high stability at pH (3-9) and temperatures (20-60 °C). Km (Michaelis-Menten) of Lac, MnP and LiP crude enzyme was 2.25, 1.79 and 0.72 mM respectively. The decolourization of Remazol Brilliant Blue R by the crude enzyme was 84.84 %. The techno-economic analysis was assessed for a production unit with an annual operating time for enzymatic production and application is 7920 h/year and 100 m3 of the capacity. The process would produce 27,000 cm3 of crude enzyme with a price of USD 0.107 per cm3 compared to USD 1 per cm3 of the current commercial enzyme. The findings indicated that pumpkin peels have potential as a production substrate for oxidative enzymes from A. iizukae EAN605 and is economically feasible.

Inactivating pathogenic bacteria in greywater by biosynthesized Cu/Zn nanoparticles from secondary metabolite of Aspergillus iizukae; optimization, mechanism and techno economic analysis.

The inactivation of antibiotic resistant Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) seeded in greywater by bimetallic bio-nanoparticles was optimized by using response surface methodology (RSM). The bimetallic nanoparticles (Cu/Zn NPs) were synthesized in secondary metabolite of a novel fungal strain identified as Aspergillus iizukae EAN605 grown in pumpkin medium. Cu/Zn NPs were very effective for inhibiting growth of E. coli and S. aureus. The maximum inactivation was optimized with 0.028 mg mL-1 of Cu/Zn NPs, at pH 6 and after 60 min, at which the reduction of E. coli and S. aureus was 5.6 vs. 5.3 and 5.2 vs. 5.4 log reduction for actual and predicted values, respectively. The inactivation mechanism was described based on the analysis of untreated and treated bacterial cells by Field emission scanning electron microscopy (FESEM), Energy Dispersive X-Ray Spectroscopy (EDS), Atomic Force Microscopy (AFM) revealed a damage in the cell wall structure due to the effect of Cu/Zn NPs. Moreover, the Raman Spectroscopy showed that the Cu/Zn NPs led to degradation of carbohydrates and amino structures on the bacteria cell wall. The Fourier transform infrared spectroscopy (FTIR) analysis confirmed that the destruction take place in the C-C bond of the functional groups available in the bacterial cell wall. The techno economic analysis revealed that the biosynthesis Cu/Zn NPs is economically feasible. These findings demonstrated that Cu/Zn NPs can effectively inhibit pathogenic bacteria in the greywater.

Optimising of Scenedesmus sp. biomass production in chicken slaughterhouse wastewater using response surface methodology and potential utilisation as fish feeds.

Production of Scenedesmus sp. biomass in chicken slaughterhouse wastewater (CSWW) is a promising alternative technique for commercial culture medium due to the high nutritional content of the generated biomass to be used as fish feeds. The current work deals with optimising of biomass production in CSWW using response surface methodology (RSM) as a function of two independent variables, namely temperature (10-30 °C) and photoperiod (6-24 h). The potential application of biomass yield as fish feeds was evaluated based on carbohydrate, protein and lipid contents. The results revealed that the best operating parameters for Scenedesmus sp. biomass production with high contents of carbohydrates, proteins and lipids were determined at 30 °C and after 24 h. The actual and predicted values were 2.47 vs. 3.09 g, 1.44 vs. 1.27 µg/mL, 29.9 vs. 31.60% and 25.75 vs. 28.44%, respectively. Moreover, the produced biomass has a high concentration of fatty acid methyl ester (FAME) as follows: 35.91% of C15:1; 17.58% of C24:1 and 14.11% of C18:1N9T. The biomass yields have 7.98% of eicosapentaenoic acid (EPA, C20:5N3) which is more appropriate as fish feeds. The Fourier transform infrared (FTIR) analysis of biomass revealed that the main functional groups included hydroxyl (OH), aldehyde (=C-H), alkanes and acyl chain groups. Scanning electron micrograph (SEM) and energy-dispersive X-ray spectroscopic analysis (EDS) indicated that the surface morphology and element distribution in biomass produced in BBM and CSWW were varied. The findings have indicated that the biomass produced in CSWW has high potential as fish feeds.

Optimizing of pharmaceutical active compounds biodegradability in secondary effluents by ß-lactamase from Bacillus subtilis using central composite design.

Biodegradation of pharmaceuticals active compounds (PACs) in secondary effluents by using B. subtilis 2012WTNC as a function of ß-lactamase was optimized using response surface methodology (RSM) designed by central composite design (CCD). Four factors including initial concentration of bacteria (1-6 log10 CFU mL-1), incubation period (1-14 days), incubation temperature (20-40 °C) and initial concentration of PACs (1-5 mg L-1) were investigated. The optimal operating factors for biodegradation process determined using response surface methodology (RSM) was recorded with 5.57 log10 CFU mL-1 of B. subtilis, for 10.38 days, at 36.62 °C and with 4.14 mg L-1 of (cephalexin/amoxicillin) with R2 coefficient of 0.99. The biodegradation was 83.81 and 93.94% respectively. The relationship among the independent variables was significant (p < 0.05) with 95% of confidence level at the best operating parameters. The bioassay for PACs after the degradation process revealed that no residual antibiotic activity was detected of amoxicillin and cephalexin against E. coli and S. aureus after degradation using B. subtilis which reflects the higher potential of bacteria to biodegrade PACs in secondary effluents. B. subtilis has the potential for biodegradation of PACs in the secondary effluents.

Microalgal biomass production through phycoremediation of fresh market wastewater and potential applications as aquaculture feeds.

Microalgal biomass produced from the phycoremediation of wastewater represents an important protein source, lipids, and natural antioxidants and bioproducts. Therefore, the microalgal biomass and their derived compounds are used in animal and aquaculture feed as well as human nutrition and health products. Many microalgal species have shown promising potential for many bioproducts. However, significant processes to find the optimum quality and quantity of microalgal biomass are still required especially when it is used as a replacement for aquaculture feed. The limitations lie in the selection of microalgal species and their production. The present review discusses the potential generation of bioproducts from microalgal biomass resulting from the phycoremediation of wet market wastewater. The consortium approach in wastewater treatment and the comparison between biomass production and available common feeds for aquaculture were reviewed.

Harvesting of microalgae biomass from the phycoremediation process of greywater.

The wide application of microalgae in the field of wastewater treatment and bioenergy source has improved research studies in the past years. Microalgae represent a good source of biomass and bio-products which are used in different medical and industrial activities, among them the production of high-valued products and biofuels. The present review focused on greywater treatment through the application of phycoremediation technique with microalgae and presented recent advances in technologies used for harvesting the microalgae biomass. The advantages and disadvantages of each method are discussed. The microbiological aspects of production, harvesting and utilization of microalgae biomass are viewed.

A monitoring of environmental effects from household greywater reuse for garden irrigation.

The option of reusing greywater is proving to be increasingly attractive to address the water shortage issue in many arid and semiarid countries. Greywater represents a constant resource, since an approximately constant amount of greywater is generated from kitchen, laundries, bathroom in every household daily, independent of the weather. However, the use of greywater for irrigation in particular for household gardening may pose major hazards that have not been studied thoroughly. In this study, a 1-year monitoring was conducted in four selected households in Perth, Western Australia. The aim of the monitoring works is to investigate the variability in the greywater flow and quality, and to understand its impact in the surrounding environments. Case studies were selected based on different family structure including number, ages of the occupants, and greywater system they used. Samples of greywater effluent (showers, laundries, bathtub, and sinks), leachate, soil, and plants at each case study were collected between October 2008 and December 2009 which covered the high (spring/summer) and low (autumn/winter) production of greywater. Physical and chemical tests were based on the literature and expected components of laundry and bathroom greywater particularly on greywater components likely to have detrimental impacts on soils, plants, and other water bodies. Monitoring results showed the greywater quality values for BOD, TSS, and pH which sometimes fell outside the range as stipulated in the guidelines. The soil analyses results showed that salinity, SAR, and the organic content of the soil increased as a function of time and affected the plant growth. Nutrient leaching or losses from soil irrigated with greywater shows the movement of nutrients and the sole impact from greywater in uncontrolled plots in case studies is difficult to predicted due to the influence of land dynamics and activities. Investigative and research monitoring was used to understand greywater irrigation in households. Greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater. Investigative and research monitoring was indicated that greywater quality is very site specific and difficult to predetermine or control except for the use of some recommended household products when using greywater.