Bioremoval of heavy metals from aqueous solution using dead biomass of indigenous fungi derived from fertilizer industry effluents: isotherm models evaluation and batch optimization

The present work investigated the utilization of dead biomass of the highly multi-heavy metals tolerant indigenous fungal strain NRCA8 isolated from the mycobiome of fertilizer industry effluents that containing multiple heavy metal ions at high levels to remove Pb2+, Ni2+, Zn2+, and Mn2+ as multiple solutes from multi-metals aqueous solutions for the first time. Based on morphotype, lipotype and genotype characteristics, NRCA8 was identified as Cladosporium sp. NRCA8. The optimal conditions for the bioremoval procedure in the batch system were pH 5.5 for maximum removal (91.30%, 43.25%, and 41.50%) of Pb2+, Zn2+ and Mn2+ but pH 6.0 supported the maximum bioremoval and uptake of Ni2+ (51.60% and 2.42 mg/g) by NRCA8 dead biomass from the multi-metals aqueous solution, respectively. The 30 min run time supported the highest removal efficiency and uptake capacity of all heavy metals under study. Moreover, the equilibrium between the sorbent NRCA8 fungal biomass and sorbates Ni2+, Pb2+ and Zn2+ was attained after increasing the dead biomass dose to 5.0 g/L. Dead NRCA8 biomass was described by scanning electron microscopy, energy-dispersive X-ray spectroscopy and Fourier transform infrared spectrometer before and after biosorption of Pb2+, Ni2+, Zn2+ and Mn2+ under multiple metals system. The Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich isotherms were applied to characterize the adsorption equilibrium between Pb2+, Ni2+, Mn2+ and Zn2+ and the adsorbent NRCA8. By comparing the obtained coefficient of regression (R2) by Freundlich (0.997, 0.723, 0.999, and 0.917), Langmiur (0.974, 0.999, 0.974, and 0.911) and Dubinin-Radushkevich (0.9995, 0.756, 0.9996 and 0.900) isotherms values for Pb2+, Zn2+, Ni2+ and Mn2+ adsorption, respectively, it was found that the isotherms are proper in their own merits in characterization the possible of NRCA8 for removal of Pb2+, Zn2+, Ni2+ and Mn2+. DKR isotherm is the best for Pb2+ and Ni2+ (0.9995 and 0.9996) while Langmiur isotherm giving a good fit to the Zn2+ sorption (0.9990) as well as Freundlich isotherm giving a good fit to the Mn2+ sorption (0.9170). The efficiencies of Cladosporium sp. NRCA8 dead biomass for bioremoval of heavy metals from real wastewater under the optimized conditions were Pb2+, Ag+, Mn2+, Zn2+ and Al3+ ˃ Ni2+ ˃ Cr6+ ˃ Co2+ ˃ Fe3+ ˃ Cu2+ ˃ Cd2+. Dead NRCA8 biomass showed efficient ability to adsorb and reduce harmful components in the industrial effluents to a level acceptable for discharge into the environment.

Multimetal bioremediation from aqueous solution using dead biomass of Mucor sp. NRCC6 derived from detergent manufacturing effluent

Among ten metal-tolerant fungal isolates obtained from the microbiomes of detergent industry effluent, Mucor sp. NRCC6 showed the highest tolerance and an adaptive behavior toward the heavy metals Ni2+, Pb2+, Mn2+, and Zn2+. It gave the highest growth rates 0.790 ± 0.59, 0.832 ± 0.32, 0.774 ± 0.40, and 0.741 ± 1.06 mm/h along with the lowest growth inhibition 9.19, 4.37, 11.04, and 14.83% in the presence of Pb2+, Zn2+, Ni2+, and Mn2+, respectively, at a concentration of 5.0 g/L. Then, Mucor sp. NRCC6 was selected as a biotrap for the removal of these heavy metals. The optimized operating conditions were detected to be pH 6.0 for Pb2+, Zn2+, and Mn2+ and pH 5.5 for Ni2+ at 30 °C; agitation speed 150 rpm; contact time 30 min for Mn2+ and Ni2+, 30-60 min for Pb2+, and 90-180 min for Zn2+; NRCC6 biomass dosage 5.0 g/L for Ni2+ and Pb2+ and 10.0 g/L for Mn2+ and Zn2+; and initial concentration 12 mg/L of each ion in the multimetal aqueous solutions. Under these optimized conditions, the adsorption capacity for Pb2+, Ni2+, Mn2+, and Zn2+ reached 98.75, 59.25, 58.33, and 50.83%. The Langmuir isotherm was the best for describing the adsorption of Zn2+ (0.970) and Mn2+ (0.977). The Freundlich isotherm significantly giving a good fit to the adsorption of Pb2+ (0.998) while the adsorption of Ni2+ onto NRCC6 biomass can follow DKR (0.998). Furthermore, the current study revealed that Mucor sp. NRCC6 fungus is a new efficient and eco-friendly method that revealed a maximum removal of 100% for Pb2+ and Zn2+ as well as 97.39, 88.70, 78.95, 74.0, 70.22, 68.57, and 60.0% for Ni2+, Mn2+, Cd2+, Cu2+, Fe3+, As2+, and Cr6+ from the industrial wastewater, respectively.

Bioremoval of some heavy metals from aqueous solutions by two different indigenous fungi Aspergillus sp. AHM69 and Penicillium sp. AHM96 isolated from petroleum refining wastewater

Myco-remediation of heavy metals using indigenous fungi of different petroleum refining areas in Egypt was applied. Among the physicochemical parameters determined in these refineries effluents, the highest levels of heavy metals were recorded for the most toxic heavy metals Fe³⁺ and Co²⁺. The fungal isolates under the isolation codes AHM69 and AHM96 isolated from the mycobiome of Mostorod and Tanta refineries, respectively showed the best bioremoval efficiency toward heavy metals from the real wastewater mixture and polycyclic aromatic hydrocarbons from aqueous solutions. Based on phenotypic and genotypic analysis they were identified as Aspergillus sp. AHM69 and Penicillium sp. AHM96. The optimum conditions for the best bioremoval of Fe³⁺ and Co²⁺ from aqueous solutions by Aspergillus sp. AHM69 were live biomass, temperature 45–55 °C, pH 4.5–5.0, contact time 180 min, metal concentration equal to 1000 and 400 mg/L of Fe³⁺ and Co²⁺ with live fungal biomass dose of 0.5% and 0.4% with Fe³⁺ and Co²⁺, respectively. Concerning to the biomass of Penicillium sp. AHM96, the optimum operation conditions for the best removal of Fe³⁺ and Co²⁺ were 45 °C, pH 5.0 and 400 mg/L of Fe³⁺ with 1.0% biosorbent dosage or 1000 mg/L of Co²⁺ with 0.5% biosorbent dosage for 180 min as process time. Furthermore, FTIR analysis showed masking, shifting, creating and absenting of different functional groups in the fungal biomass surface of AHM96 and AHM69 strains in the presence of Fe³⁺ and Co²⁺ compared to unloaded biomasses. Microscopy with Energy Dispersive X-ray analysis (SEM-EDX) indicated that the removal of Fe³⁺ and Co²⁺ by fungi AHM69 and AHM96 was via biosorption and bioaccumulation on the biomass surface. Our results suggested that in the near future, fungal treatment is likely to outperform and replace other chemical and biological treatments in industrial wastewater treatment for oil refining.

Assessment of the phylogenetic analysis and antimicrobial, antiviral, and anticancer activities of marine endophytic Streptomyces species of the soft coral Sarcophyton convolutum

In the present work, the extensive biological activities of marine endophytic Streptomyces strains isolated from marine soft coral Sarcophyton convolutum have been demonstrated. Within fifty-one Streptomyces isolates evaluated for their hydrolytic enzymes and enzyme inhibitors productivities, six isolates showed the hyperactivities. Pharmaceutical metabolites productivities evaluated include enzymes (alkaline protease, L-asparaginase, L-glutaminase, tyrosinase, and L-methioninase) and enzyme inhibitors (inhibitors of α-amylase, hyaluronidase, β-lactamase, α-glucosidase, and β-glucosidase). These isolates were identified based on their morphological, biochemical, and genetic characteristics as Streptomyces sp. MORSY 17, Streptomyces sp. MORSY 22, Streptomyces sp. MORSY 25, Streptomyces sp. MORSY 36, Streptomyces sp. MORSY 45, and Streptomyces sp. MORSY 50. Moreover, in further evaluation, these strains exhibited wide spectrum of antimicrobial (against bacteria and fungi), antiviral (against hepatitis C virus), antibiofilm against biofilm-forming bacteria (methicillin-resistant Staphylococcus aureus and multidrug-resistant Pseudomonas species), and anti-proliferative activities (against liver and colon carcinoma cell lines). The GC-MS analysis of the hyperactive strains MORSY 17 and MORSY 22 revealed the presence of different bioactive agents in the ethyl acetate extract of both strains.

WITHDRAWN: Incidence of methicillin resistant Staphylococcus aureus (MRSA) in microbial community of cancer patients and evaluation of their resistant pattern

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In Vivo Evaluation of the Toxic Effect of Ethyl Acetate Extracts of Marine Antibiotic Resistance Pseudomonas Species Derived from the Red Sea

Eighty-nine cultured Pseudomonas species isolated from the sediment and water samples collected from five industrial Red Sea regions that have been affected by petroleum and industry. Genotypic (exoT, exoS, exoU, exoY, lasA, lasB, rhlA, rhlB, Pf1, PAGI-1, -2, and -3) and phenotypic (DNase, elastase, lipase, protease, siderophore, antibiotic resistance patterns) characteristics were determined. Out of these isolates, nine Pseudomonas isolates were selected as the hyperactive virulence factors producers along with highly resistant pattern against all antibiotics of different classes included in this study. They were subjected to phenotypic and chemotypic characterization as well as molecular identification through 16S rRNA gene amplification and sequencing. The bioactive metabolites of these nine strains were extracted by ethyl acetate followed by evaluating their cytotoxic activity toward liver tissues, kidney tissues, and other biochemical activities in rat. Both EGY6 and EGY8 caused the highest significant reduction in the levels of packed cell volume (PCV), red blood cell count (RBC), and hemoglobin (Hb), which indicate that these Pseudomonas strain metabolites could cause anemia and toxic effects on hematological values in animals that were infected with them. Rats treated with the most toxic extract, EGY8, showed severe histopathological alterations in liver and kidney.

Construction of Potent Recombinant Strain Through Intergeneric Protoplast Fusion in Endophytic Fungi for Anticancerous Enzymes Production Using Rice Straw

Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.

Genome Shuffling of Mangrove Endophytic Aspergillus luchuensis MERV10 for Improving the Cholesterol-Lowering Agent Lovastatin under Solid State Fermentation

In the screening of marine mangrove derived fungi for lovastatin productivity, endophytic Aspergillus luchuensis MERV10 exhibited the highest lovastatin productivity (9.5 mg/gds) in solid state fermentation (SSF) using rice bran. Aspergillus luchuensis MERV10 was used as the parental strain in which to induce genetic variabilities after application of different mixtures as well as doses of mutagens followed by three successive rounds of genome shuffling. Four potent mutants, UN6, UN28, NE11, and NE23, with lovastatin productivity equal to 2.0-, 2.11-, 1.95-, and 2.11-fold higher than the parental strain, respectively, were applied for three rounds of genome shuffling as the initial mutants. Four hereditarily stable recombinants (F3/3, F3/7, F3/9, and F3/13) were obtained with lovastatin productivity equal to 50.8, 57.0, 49.7, and 51.0 mg/gds, respectively. Recombinant strain F3/7 yielded 57.0 mg/gds of lovastatin, which is 6-fold and 2.85-fold higher, respectively, than the initial parental strain and the highest mutants UN28 and NE23. It was therefore selected for the optimization of lovastatin production through improvement of SSF parameters. Lovastatin productivity was increased 32-fold through strain improvement methods, including mutations and three successive rounds of genome shuffling followed by optimizing SSF factors.

Evaluation and enhancement of heavy metals bioremediation in aqueous solutions by Nocardiopsis sp. MORSY1948, and Nocardia sp. MORSY2014

An analysis of wastewater samples collected from different industrial regions of Egypt demonstrated dangerously high levels of nickel (0.27-31.50mgL(-1)), chromium (1.50-7.41mgL(-1)) and zinc (1.91-9.74mgL(-1)) in the effluents. Alarmingly, these heavy metals are among the most toxic knownones to humans and wildlife. Sixty-nine Actinomycete isolates derived from contaminated sites were evaluated under single, binary, and ternary systems for their biosorption capacity for Ni(2+), Cr(6+) and Zn(2+) from aqueous solutions. The results of the study identified isolates MORSY1948 and MORSY2014 as the most active biosorbents. Phenotypic and chemotypic characterization along with molecular phylogenetic evidence confirmed that the two strains are members of the Nocardiopsis and Nocardia genera, respectively. The results also proved that for both the strains, heavy metal reduction was more efficient with dead rather than live biomass. The affinity of the dead biomass of MORSY1948 strain for Ni(2+), Cr(6+) and Zn(2+) under the optimized pH conditions of 7, 8 and 7, respectively at 40°C temperature with 0.3% biosorbent dosage was found to be as follows: Ni(2+) (87.90%)>Zn(2+) (84.15%)>Cr(6+) (63.75%). However, the dead biomass of MORSY2014 strain under conditions of pH 8 and 50°C temperature with 0.3% biosorbent dose exhibited the highest affinity which was as follows: Cr(6+) (95.22%)>Ni(2+) (93.53%)>Zn(2+) (90.37%). All heavy metals under study were found to be removed from aqueous solutions in entirety when the sorbent dosage was increased to 0.4%.