Biological Treatment of Real Textile Effluent Using Aspergillus flavus and Fusarium oxysporium and Their Consortium along with the Evaluation of Their Phytotoxicity

"Stop, Little Pot" as the Motto of Suppressive Management of Various Microbial Consortia

The unresolved challenges in the development of highly efficient, stable and controlled synthetic microbial consortia, as well as the use of natural consortia, are very attractive for science and technology. However, the consortia management should be done with the knowledge of how not only to accelerate but also stop the action of such "little pots". Moreover, there are a lot of microbial consortia, the activity of which should be suppressively controlled. The processes, catalyzed by various microorganisms being in complex consortia which should be slowed down or completely cancelled, are typical for the environment (biocorrosion, landfill gas accumulation, biodegradation of building materials, water sources deterioration etc.), industry (food and biotechnological production), medical practice (vaginitis, cystitis, intestinal dysbiosis, etc.). The search for ways to suppress the functioning of heterogeneous consortia in each of these areas is relevant. The purpose of this review is to summarize the general trends in these studies regarding the targets and new means of influence used. The analysis of the features of the applied approaches to solving the main problem confirms the possibility of obtaining a combined effect, as well as selective influence on individual components of the consortia. Of particular interest is the role of viruses in suppressing the functioning of microbial consortia of different compositions.

Surface Modifications of Superparamagnetic Iron Oxide Nanoparticles with Chitosan, Polyethylene Glycol, Polyvinyl Alcohol, and Polyvinylpyrrolidone as Methylene Blue Adsorbent Beads

Due to the negative impacts the dye may have on aquatic habitats and human health, it is often found in industrial effluent and poses a threat to public health. Hence, to solve this problem, this study developed magnetic adsorbents that can remove synthetic dyes like methylene blue. The adsorbent, in the form of beads, consists of a polymer blend of chitosan, polyethylene glycol, polyvinyl alcohol, polyvinylpyrrolidone, and superparamagnetic iron oxide nanoparticles (average size of 19.03 ± 4.25 nm). The adsorption and desorption of MB from beads were carried out at pH values of 7 and 3.85, respectively. At a concentration of 9 mg/L, the loading capacity and the loading amount of MB after 5 days peaked at 29.75 ± 1.53% and 297.48 ± 15.34 mg/g, respectively. Meanwhile, the entrapment efficiency of MB reached 29.42 ± 2.19% at a concentration of 8 mg/L. The cumulative desorption capacity of the adsorbent after 13 days was at its maximum at 7.72 ± 0.5%. The adsorption and desorption kinetics were evaluated.

Tannery effluent treatments with mangrove fungi, grass root biomass, and biochar

Tannery effluents contain high amounts of polluting chemicals, such as salts and heavy metals released often to surface waters. New economic and eco-friendly purification methods are needed. Two adsorbing materials and five salt-tolerant fungal isolates from mangrove habitat were studied. Purification experiments were carried out using the pollutant adsorbents biochar and the biomass of vetiver grass (Chrysopogon zizanioides) roots and the fungi Cladosporium cladosporioides, Phomopsis glabrae, Aspergillus niger, Emericellopsis sp., and Scopulariopsis sp., which were isolated from mangrove sediment. They efficacy to reduce pollutants was studied in different combinations. Salinity, turbidity, total dissolved solids, total suspended solids, phenols, nitrogen, ammonia. Biological and chemical oxygen demand (BOD, COD) and several heavy metals were measured. The adsorbents were efficient reducing the pollutants to 15-50% of the original. The efficiency of the combination of biochar and roots was generally at the same level as the adsorbents alone. Some pollutants such as turbidity, COD and ammonium were reduced slightly more by the combination than the adsorbents alone. From all 14 treatments, Emericellopsis sp. with biochar and roots appeared to be the most efficient reducing pollutants to < 10-30%. BOD and COD were reduced to ca 5% of the original. The treatment was efficient in reducing also heavy metals (As, Cd, Cr, Mn Pb, Zn). The fungal species originating from the environment instead of the strains present in the tannery effluent reduced pollutants remarkably and the adsorbents improved the reduction efficiency. However, the method needs development for effluents with high pollutant concentrations to fulfil the environmental regulations.

Microorganism-mediated bioremediation of dyes from contaminated soil: Mechanisms, recent advances, and future perspectives

Many methods have been proposed for the remediation of dye-contaminated soils, a widespread form of environment pollution. Bioremediation, it is hoped, can combine ecological benefits with efficiency of dye decontamination. We review the types and sources of dye contaminants; their possible effects on plant, animal, and human health; and emerging strategies for microbial bioremediation. Challenges, limitations, recommendations for future research, and prospects for large-scale commercialization of microbial bioremediation are discussed.

Biological treatment of triclosan using a novel strain of Enterobacter cloacae and introducing naphthalene dioxygenase as an effective enzyme

In recent years, triclosan (TCS) has been widely used as an antibacterial agent in personal care products due to the spread of the Coronavirus. TSC is an emerging contaminant, and due to its stability and toxicity, it cannot be completely degraded through traditional wastewater treatment methods. In this study, a novel strain of Enterobacter cloacae was isolated and identified that can grow in high TCS concentrations. Also, we introduced naphthalene dioxygenase as an effective enzyme in TCS biodegradation, and its role during the removal process was investigated along with the laccase enzyme. The change of cell surface hydrophobicity during TCS removal revealed that a glycolipid biosurfactant called rhamnolipid was involved in TCS removal, leading to enhanced biodegradation of TCS. The independent variables, such as initial TCS concentration, pH, removal duration, and temperature, were optimized using the response surface method (RSM). As a result, the maximum TCS removal (97%) was detected at a pH value of 7 and a temperature of 32 °C after 9 days and 12 h of treatment. Gas chromatography-mass spectrometry (GC/MS) analysis showed five intermediate products and a newly proposed pathway for TCS degradation. Finally, the phytotoxicity experiment conducted on Cucumis sativus and Lens culinaris seeds demonstrated an increase in germination power and growth of stems and roots in comparison to untreated water. These results indicate that the final treated water was less toxic.

Exploring the antimicrobial, antioxidant, anticancer, biocompatibility, and larvicidal activities of selenium nanoparticles fabricated by endophytic fungal strain Penicillium verhagenii

Herein, four endophytic fungal strains living in healthy roots of garlic were used to produce selenium nanoparticles (Se-NPs) via green synthesis. Penicillium verhagenii was found to be the most efficient Se-NPs producer with a ruby red color that showed maximum surface plasmon resonance at 270 nm. The as-formed Se-NPs were crystalline, spherical, and well-arranged without aggregation, and ranged from 25 to 75 nm in size with a zeta potential value of -32 mV, indicating high stability. Concentration-dependent biomedical activities of the P. verhagenii-based Se-NPs were observed, including promising antimicrobial activity against different pathogens (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Candida albicans, C. glabrata, C. tropicalis, and C. parapsilosis) with minimum inhibitory concentration (MIC) of 12.5-100 µg mL^-1. The biosynthesized Se-NPs showed high antioxidant activity with DPPH-scavenging percentages of 86.8 ± 0.6% at a concentration of 1000 µg mL^-1 and decreased to 19.3 ± 4.5% at 1.95 µg mL^-1. Interestingly, the Se-NPs also showed anticancer activity against PC3 and MCF7 cell lines with IC₅₀ of 225.7 ± 3.6 and 283.8 ± 7.5 µg mL^-1, respectively while it is remaining biocompatible with normal WI38 and Vero cell lines. Additionally, the green synthesized Se-NPs were effective against instar larvae of a medical insect, Aedes albopictus with maximum mortality of 85.1 ± 3.1, 67.2 ± 1.2, 62.10 ± 1.4, and 51.0 ± 1.0% at a concentration of 50 µg mL^-1 for I, II, III, and IV-instar larva, respectively. These data highlight the efficacy of endophytic fungal strains for cost-effective and eco-friendly Se-NPs synthesis with different applications.

Low-temperature synthesis, characterization and photocatalytic properties of lanthanum vanadate LaVO4

In this study, we have successfully prepared tetragonal lanthanum vanadate LaVO₄ nanoparticles by a facile co-precipitation method at room temperature. The obtained materials were characterized using different structural and micro-structural techniques such as the characterization by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectrum (DRS), transmission electron microscopy (TEM), and Raman spectrometry. The obtained structure is crystallized in single tetragonal phase with pin-like nanostructure. A main optical transition with bandgap energy of 3.26 eV is evidenced, and the average lifetime of charges carriers was found to be 1 ns Furthermore, the photoluminescence occurs in the visible light range. The photocatalytic activity was evaluated by the photocatalytic degradation of methylene blue (MB) with initial concentration of 10 mg L^-1. The result indicates that LaVO₄ particles showed a best photocatalytic activity of 98.2% degradation for methylene blue solution after irradiation of 90 min under visible light. Furthermore, the photocatalytic mechanism and reusability were studied.

Textile effluents decolourization potential of metal tolerant Aspergillus species and optimization of biomass concentration and temperature

This research was performed to assess the physicochemical properties of textile effluents collected from different sampling points (industrial park, Hosur, Tamil Nadu, India) and also evaluate the multiple metal tolerance efficiency of pre-isolated Aspergillus flavus. Moreover, their textile effluent decolourization potential was investigated and quantity and temperature required for effective bioremediation was optimized. About 5 textile effluent samples (S0, S1, S2, S3, and S4) were collected from various sampling points and noted that certain physicochemical properties (pH: 9.64 ± 0.38, Turbidity: 18.39 ± 1.4 NTU, Cl^-: 3185.38 ± 15.8 mg L^-1, BOD: 82.52 ± 6.9 mg L^-1, COD: 342.28 ± 8.9 mg L^-1, Ni: 74.21 ± 4.31 mg L^-1, Cr: 48.52 ± 18.34 mg L^-1, Cd: 34.85 ± 1.2 mg L^-1, Zn: 25.52 ± 2.4 mg L^-1, Pb: 11.25 ± 1.5 mg L^-1, Hg: 1.8 ± 0.05 mg L^-1, and As: 7.1 ± 0.41 mg L^-1) were beyond the permissible limits. The A. flavus, showed remarkable metal tolerance to Pb, As, Cr, Ni, Cu, Cd, Hg, and Zn on PDA plates with elevated dosage up to 1000 μg mL^-1. The optimal dosage required for effective decolourization was found as 3 g (48.2%) and compare to dead biomass (42.1%) of A. flavus, the viable biomass showed remarkable decolourization activity on textile effluents in a short duration of treatment process. The optimal temperature for effective decolourization by viable biomass was found at 32 ᵒC. The toxic effects of S4 samples treated at 32 ᵒC on O. sativa as well as brine shrimp larvae were significantly reduced. These findings show that pre-isolated A. flavus viable biomass can be used to decolorize metal-enriched textile effluent. Furthermore, the effectiveness of their metals remediation should be investigated using ex-situ and ex-vivo approaches.

Sustainable consideration for traditional textile handloom cluster/village in pollution abatement - A case study

Decentralized handlooms are being traditionally practised throughout India. Siripuram village known for traditional Pochampally/Ikat work was considered as a case study for detailed investigation towards providing a sustainable solution. Nearly 65% of village population solely depend on weaving and dyeing works as primary occupation based on the household survey and generated wash water of 127 KLD on an average from the dyeing operations. Initially, a topographical survey (Aerial drone; PHANTOM 4 RTK UAV) was carried out to understand the drainage pattern, elevations, contours and interlinked with domestic and dyeing functions. The characteristics of combined wastewater and dye wash water were studied at lab scale using sequential batch (SBR) operation under aerobic (SBRAe) and aerobic-anoxic (SBRAex) microenvironments. SBRAex microenvironment showed effective organic and nutrients removal due to infused anoxic microenvironment. Treatment studies depicted 76.2% of organic fraction, 73.3% of phosphate, and 81.6% of nitrate removal. Based on the lab scale studies a closed-loop decentralized effluent treatment system was designed to ensure zero-liquid discharge (ZLD).

Antifungal Activity of Cell-Free Filtrate of Probiotic Bacteria Lactobacillus rhamnosus ATCC-7469 against Fungal Strains Isolated from a Historical Manuscript

Herein, twelve fungal strains were isolated from a deteriorated historical manuscript dated back to the 18th century. The obtained fungal strains were identified, using the traditional method and ITS sequence analysis, as Cladosporium herbarum (two strains), Aspergillus fumigatus (five strains), A. ustus (one strain), A. flavus (two strains), A. niger (one strain), and Penicillium chrysogenum (one strain). The ability of these fungal strains to degrade the main components of the paper was investigated by their activity to secrete extracellular enzymes including cellulase, amylase, gelatinase, and pectinase. The cell-free filtrate (CFF) ability of the probiotic bacterial strain Lactobacillus rhamnosus ATCC-7469 to inhibit fungal growth was investigated. The metabolic profile of CFF was detected by GC-MS analysis, which confirmed the low and high molecular weight of various active chemical compounds. The safe dose to be used for the biocontrol of fungal growth was selected by investigating the biocompatibility of CFF and two normal cell lines, Wi38 (normal lung tissue) and HFB4 (normal human skin melanocyte). Data showed that the CFF has a cytotoxic effect against the two normal cell lines at high concentrations, with IC₅₀ values of 525.2 ± 9.8 and 329.1 ± 4.2 µg mL^-1 for Wi38 and HFB4, respectively. The antifungal activity showed that the CFF has promising activity against all fungal strains in a concentration-dependent manner. The highest antifungal activity (100%) was recorded for a concentration of 300 µg mL^-1 with a zone of inhibition (ZOI) in the ranges of 21.3 ± 0.6 to 17.7 ± 0.5 mm. At a concentration of 100 µg mL^-1, the activity of CFF remained effective against all fungal strains (100%), but its effectiveness decreased to only inhibit the growth of eight strains (66%) out of the total at 50 µg mL^-1. In general, probiotic bacterial strains containing CFF are safe and can be considered as a potential option for inhibiting the growth of various fungal strains. It is recommended that they be used in the preservation of degraded historical papers.

Photocatalytic Performance of Functionalized Biopolymer for Neodymium (III) Sorption and the Recovery from Leachate Solution

Successive grafting of new sorbent bearing amino phosphonic groups based on chitosan nano magnetite particles was performed through successive coupling with formaldehyde. The produced composite was characterized by the high sorption capacity toward rare earth elements (REEs) and consists of different types of functional groups (phosphonic, hydroxyls and amine groups) that are used for enhancing the sorption properties. The chemical modification and the sorption mechanism were investigated through different analytical tools; i.e., FTIR, SEM, SEM-EDX, TGA, BET (surface area) and pHpzc. The sorption was investigated toward Nd(III) as one of the REE(III) members under ultraviolet (UV) and visible light (VL) conditions. The optimum sorption was found at pH0 4 and the sorption capacity was recorded at 0.871 and 0.779 mmol Nd g−1 under UV and VL respectively. Sorption isotherms and uptake kinetics were fitted by Langmuir and Sips and by pseudo-first order rate equation (PFORE) for the functionalized sorbent, respectively. The sorbent showed a relatively high-speed sorption kinetic (20 min). The bounded metal ions were progressively eluted using 0.2 M HCl solution with a desorption rate 10–15 min, while the loss in the total capacity after a series of sorption recycling (sorption/desorption) (five cycles) was limited (around 3%) with 100% of the desorption efficiency, indicating the high stability of the sorbent toward an acidic medium. The sorbent was used for the recovery of REEs from leach liquor residue after pretreatment for the extraction of particular elements. From these results (high loading capacity, high selectivity and high stability against acid treatments), we can see that the sorbent is a promising tool for the selective recovery of rare earth elements in the field of metal valorization.

A mini review on green nanotechnology and its development in biological effects

The utilization of living organisms for the creation of inorganic nanoscale particles is a potential new development in the realm of biotechnology. An essential milestone in the realm of nanotechnology is the process of creating dependable and environmentally acceptable metallic nanoparticles. Due to its increasing popularity and ease, use of ambient biological resources is quickly becoming more significant in this field of study. The phrase "green nanotechnology" has gained a lot of attention and refers to a variety of procedures that eliminate or do away with hazardous compounds to repair the environment. Green nanomaterials can be used in a variety of biotechnological sectors such as medicine and biology, as well as in the food and textile industries, wastewater treatment and agriculture field. The construction of an updated level of knowledge with utilization and a study of the ambient biological systems that might support and revolutionize the creation of nanoparticles (NPs) are presented in this article.

Anaerobic Membrane Bioreactor (AnMBR) for the Removal of Dyes from Water and Wastewater: Progress, Challenges, and Future Perspectives

The presence of dyes in aquatic environments can have harmful effects on aquatic life, including inhibiting photosynthesis, decreasing dissolved oxygen levels, and altering the behavior and reproductive patterns of aquatic organisms. In the initial phase of this review study, our aim was to examine the categories and properties of dyes as well as the impact of their toxicity on aquatic environments. Azo, phthalocyanine, and xanthene are among the most frequently utilized dyes, almost 70–80% of used dyes, in industrial processes and have been identified as some of the most commonly occurring dyes in water bodies. Apart from that, the toxicity effects of dyes on aquatic ecosystems were discussed. Toxicity testing relies heavily on two key measures: the LC50 (half-lethal concentration) and EC50 (half-maximal effective concentration). In a recent study, microalgae exposed to Congo Red displayed a minimum EC50 of 4.8 mg/L, while fish exposed to Disperse Yellow 7 exhibited a minimum LC50 of 0.01 mg/L. Anaerobic membrane bioreactors (AnMBRs) are a promising method for removing dyes from water bodies. In the second stage of the study, the effectiveness of different AnMBRs in removing dyes was evaluated. Hybrid AnMBRs and AnMBRs with innovative designs have shown the capacity to eliminate dyes completely, reaching up to 100%. Proteobacteria, Firmicutes, and Bacteroidetes were found to be the dominant bacterial phyla in AnMBRs applied for dye treatment. However, fouling has been identified as a significant drawback of AnMBRs, and innovative designs and techniques are required to address this issue in the future.

Vital Conditions to Remove Pollutants from Synthetic Wastewater Using Malaysian Ganoderma lucidum

Mycoremediation, a fungal-based technology, has seen tremendous growth as an effective alternative to treat industrial wastewater due to its ability to oxidise pollutant loadings. Considering the non-toxic properties and high potential degradation performance of Ganoderma lucidum, this research aims to study the performance of a Malaysian G. lucidum strain, the effect of agitation speed, and different carbon-to-nitrogen (C/N) ratio concentrations of synthetic wastewater in degrading chemical oxygen demand (COD) and ammonia. Different agitation speeds (25 rpm, 50 rpm and 100 rpm) and C/N ratios (C10N1, C13.3N1 and C16.7N1) were chosen as parameters to be analysed in this study. The best degradation of COD and ammonia with a percentage removal in the range of 95% to 100% within 30 h of treatment. ANOVA analysis was done using the response surface methodology to verify the obtained results, and it was found that mycoremediation using 100 rpm agitation provided the best results, removing more than 95% of COD and ammonia from synthetic wastewater. The microscopic analysis also showed that the structure of G. lucidum changed after wastewater treatment. This result proved that the Malaysian G. lucidum strain has a good potential in treating synthetic domestic wastewater, especially with high organic content, as a naturally sustainable bioremediation system.

Palladium Nanoparticles Incorporated Fumed Silica as an Efficient Catalyst for Nitroarenes Reduction via Thermal and Microwave Heating

The reduction of nitroarenes to arylamines is a synthetically important transformation both in the laboratory and in industry. Herein, Palladium (Pd) nanoparticles were synthesized via incorporation with mesoporous fumed silica material by doping technique. Water was used as a solvent and the as-synthetized material was reduced by using NaBH4 to ensure the total transformation of PdO into Pd nanoparticles. The synthesized sample was characterized by using inductively coupled plasma (ICP) elemental analysis, X-ray powder diffraction (XRD), N2 sorption measurement, scanning electron microscope (SEM), energy-dispersive spectroscopy (EDX), and transmission electron microscopy (TEM). Data showed that the Pd nanoparticles were successfully synthesized and supported on the mesoporous silica with an average size in the ranges of 10–20 nm, with an irregular shape. The purity of the synthesized sample was confirmed by EDX analysis which exhibits the presence of Si, O, and Pd. The catalytic activity of the prepared sample was evaluated in the heterogeneous reduction of nitroarenes to aromatic amines. Reduction reaction was monitored by Shimadzu GC-17A gas chromatography (GC, Japan) equipped with flam ionization detector and RTX-5 column, 30 m × 0.25 mm, 1-μm film thickness. Helium was used as carrier gas at flow rate 0.6 mL/min. Interestingly, the green hydrogenation of nitroarenes to primary amine compounds was achieved in an aqueous solution with high efficiency and in a short time; moreover, the reusability of heterogeneous Pd-SiO2 was performed for four repeated cycles with more than 88% of efficiency at the fourth run. Finally, the heterogeneity of catalysis with high reliability and eco-friendly processes is a super new trend of nitroarenes reduction in the industry and economic scales.

Biodegradation of Selected Hydrocarbons by Fusarium Species Isolated from Contaminated Soil Samples in Riyadh, Saudi Arabia

BACKGROUND

Microbial biodegradation of oil-hydrocarbons is one of the sustainable and cost-effective methods to remove petroleum spills from contaminated environments. The current study aimed to investigate the biodegradation abilities of three Fusarium isolates from oil reservoirs in Saudi Arabia. The novelty of the current work is that the biodegradation ability of these isolates was never tested against some natural hydrocarbons of variable compositions, such as Crude oil, and those of known components such as kerosene and diesel oils.

METHODS

The isolates were treated with five selected hydrocarbons. The hydrocarbon tolerance test in solid and liquid media was performed. The scanning electron microscope (SEM) investigated the morphological changes of treated fungi. 2, 6-Dichlorophenol Indophenol (DCPIP), drop collapse, emulsification activity, and oil Spreading assays investigated the biodegradation ability. The amount of produced biosurfactants was measured, and their safety profile was estimated by the germination assay of tomato seeds.

RESULTS

The tolerance test showed enhanced fungal growth of all isolates, whereas the highest dose inhibition response (DIR) was 77% for Fusarium proliferatum treated with the used oil (p < 0.05). SEM showed morphological changes in all isolates. DCPIP results showed that used oil had the highest biodegradation by Fusarium verticillioides and Fusarium oxysporum. Mixed oil induced the highest effect in oil spreading, drop collapse, and emulsification assay caused by F. proliferatum. The highest recovery of biosurfactants was obtained by the solvent extraction method for F. verticillioides (4.6 g/L), F. proliferatum (4.22 g/L), and F. oxysporum (3.73 g/L). The biosurfactants produced by the three isolates stimulated tomato seeds' germination more than in control experiments.

CONCLUSION

The current study suggested the possible oil-biodegradation activities induced by three Fusarium isolates from Riyadh, Saudi Arabia. The produced biosurfactants are not toxic against tomato seed germination, emphasizing their environmental sustainability. Further studies are required to investigate the mechanism of biodegradation activities and the chemical composition of the biosurfactants produced by these species.

Adsorptive removal of hazardous dye (crystal violet) using bay leaves (Laurus nobilis L.): surface characterization, batch adsorption studies, and statistical analysis

In this study, the surface properties of Laurus nobilis L. were determined by inverse gas chromatography. From this, the surface of Laurus nobilis L. was found to be an acidic ([Formula: see text]). Then, the adsorption of hazardous crystal violet dye on Laurus nobilis L. was examined. For the adsorption process, the optimum conditions were determined as contact time (60 min), adsorbent dosage (1.0 g/L), agitation rate (200 rpm), and initial pH (≅ 7). The efficiencies of initial concentration, contact time, temperature, and their binary combinations on the improvement of adsorption percentage were statistically investigated via three different two-way ANOVA analyses. Adsorption data were applied to different isotherms, and it was determined that the Langmuir isotherm (r² = 0.9998) was the most suitable isotherm for the adsorption process. The [Formula: see text] value was calculated as 400.0 mg/g at 25 °C from the Langmuir isotherm. According to kinetic models, it was observed that the adsorption occurred in three steps. According to enthalpy (+ 7.52 kJ/mol), activation energy (+ 8.91 kJ/mol), and Gibbs free energy (- 30.0 kJ/mol) values, it was determined that the adsorption occurred endothermically and spontaneously. As a result of reusability studies, it was determined that the adsorbent could be used repeatedly.

Fungal assisted bio-treatment of environmental pollutants with comprehensive emphasis on noxious heavy metals: Recent updates

In the present time of speedy developments and industrialization, heavy metals are being uncovered in aquatic environment and soil via refining, electroplating, processing, mining, metallurgical activities, dyeing and other several metallic and metal based industrial and synthetic activities. Heavy metals like lead (Pb), mercury (Hg), cadmium (Cd), arsenic (As), Zinc (Zn), Cobalt (Co), Iron (Fe), and many other are considered as seriously noxious and toxic for the aquatic environment, human, and other aquatic lives and have damaging influences. Such heavy metals, which are very tough to be degraded, can be managed by reducing their potential through various processes like removal, precipitation, oxidation-reduction, bio-sorption, recovery, bioaccumulation, bio-mineralization etc. Microbes are known as talented bio-agents for the heavy metals detoxification process and fungi are one of the cherished bio-sources that show noteworthy aptitude of heavy metal sorption and metal tolerance. Thus, the main objective of the authors was to come with a comprehensive review having methodological insights on the novel and recent results in the field of mycoremediation of heavy metals. This review significantly assesses the potential talent of fungi in heavy metal detoxification and thus, in environmental restoration. Many reported works, methodologies and mechanistic sights have been evaluated to explore the fungal-assisted heavy metal remediation. Herein, a compact and effectual discussion on the recent mycoremediation studies of organic pollutants like dyes, petroleum, pesticides, insecticides, herbicides, and pharmaceutical wastes have also been presented.

Construction of microbial consortia for microbial degradation of complex compounds

Increasingly complex synthetic environmental pollutants are prompting further research into bioremediation, which is one of the most economical and safest means of environmental restoration. From the current research, using microbial consortia to degrade complex compounds is more advantageous compared to using isolated bacteria, as the former is more adaptable and stable within the growth environment and can provide a suitable catalytic environment for each enzyme required by the biodegradation pathway. With the development of synthetic biology and gene-editing tools, artificial microbial consortia systems can be designed to be more efficient, stable, and robust, and they can be used to produce high-value-added products with their strong degradation ability. Furthermore, microbial consortia systems are shown to be promising in the degradation of complex compounds. In this review, the strategies for constructing stable and robust microbial consortia are discussed. The current advances in the degradation of complex compounds by microbial consortia are also classified and detailed, including plastics, petroleum, antibiotics, azo dyes, and some pollutants present in sewage. Thus, this paper aims to support some helps to those who focus on the degradation of complex compounds by microbial consortia.

Alleviate the Drought Stress on Triticum aestivum L. Using the Algal Extracts of Sargassum latifolium and Corallina elongate Versus the Commercial Algal Products

Herein, two seaweed extracts (Sargassum latifolium and Corallina elongate), and two commercial seaweed products (Canada power and Oligo-X) with a concentration of 5% were used to alleviate the drought stress on wheat plants. The extract of C. elongate had the highest capacity to ameliorate the deleterious effects of water scarcity followed by S. latifolium and the commercial products. The drought stress reduced wheat shoots length and the contents of pigments (chlorophyll and carotenoids), carbohydrates, and proteins. While the highest increment in the total carbohydrates and protein contents of the wheat shoot after two stages, 37-and 67-days-old, were noted in drought-stressed plants treated with C. elongate extract with values of (34.6% and 22.8%) and (51.9% and 39.5%), respectively, compared to unstressed plants. Decreasing the activity of antioxidant enzymes, peroxidase, superoxidase dismutase, and polyphenol oxidase in drought-stressed plants treated with algal extracts indicated amelioration of the response actions. Analysis of phytohormones in wheat plants exhibited increasing GA3 and IAA contents with percentages of (20.3-13.8%) and (72.7-25%), respectively. Interestingly, all morphological and metabolic characteristics of yield were improved due to the algal treatments compared with untreated drought-stressed plants. Overall, the algal extracts, especially those from seaweed of C. elongate, could represent a sustainable candidate to overcome the damage effects of water deficiency in the wheat plant.

Mycosynthesis of Hematite (α-Fe2O3) Nanoparticles Using Aspergillus niger and Their Antimicrobial and Photocatalytic Activities

Nanoparticles (NPs) and nanomaterials (NMs) are now widely used in a variety of applications, including medicine, solar energy, drug delivery, water treatment, and pollution detection. Hematite (α-Fe₂O₃) nanoparticles (Hem-NPs) were manufactured in this work by utilizing a cost-effective and ecofriendly approach that included a biomass filtrate of A. niger AH1 as a bio-reducer. The structural and optical properties of Hem-NPs were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and UV-visible and Fourier-transform infrared (FTIR) spectroscopies. The results revealed that all of the studied parameters, as well as their interactions, had a significant impact on the crystallite size. The average diameter size of the biosynthesized Hem-NPs ranged between 60 and 80 nm. The antimicrobial and photocatalytic activities of Hem-NPs were investigated. The antimicrobial results of Hem-NPs revealed that Hem-NPs exhibited antibacterial activity against E. coli, B. subtilis, and S. mutans with MICs of 125, 31.25, and 15.62 µg/mL, respectively. Moreover, Hem-NPs exhibited antifungal activity against C. albicans and A. fumigatus, where the MICs were 2000 and 62.5 µg/mL, respectively. The efficiency of biosynthesized Hem-NPs was determined for the rapid biodegradation of crystal violet (CV) dye, reaching up to 97 percent after 150 min. Furthermore, Hem-NPs were successfully used more than once for biodegradation and that was regarded as its efficacy. In conclusion, Hem-NPs were successfully biosynthesized using A. niger AH1 and demonstrated both antimicrobial activity and photocatalytic activity against CV dye.

Environmental Impacts of Ecofriendly Iron Oxide Nanoparticles on Dyes Removal and Antibacterial Activity

Biosynthesized nanoparticles have a promising future since they are a more environmentally friendly, cost-effective, repeatable, and energy-efficient technique than physical or chemical synthesis. In this work, Purpureocillium lilacinum was used to synthesize iron oxide nanoparticles (Fe₂O₃-NPs). Characterization of mycosynthesized Fe₂O₃-NPs was done by using UV-vis spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS), and X-ray diffraction (XRD) analysis. UV-vis gave characteristic surface plasmon resonance (SPR) peak for Fe₂O₃-NPs at 380 nm. TEM image reveals that the morphology of biosynthesized Fe₂O₃-NPs was hexagonal, and their size range between 13.13 and 24.93 nm. From the XRD analysis, it was confirmed the crystalline nature of Fe₂O₃ with average size 57.9 nm. Further comparative study of photocatalytic decolorization of navy blue (NB) and safranin (S) using Fe₂O₃-NPs was done. Fe₂O₃-NPs exhibited potential catalytic activity with a reduction of 49.3% and 66% of navy blue and safranin, respectively. Further, the antimicrobial activity of Fe₂O₃-NPs was analyzed against pathogenic bacteria (Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus). The Fe₂O₃-NPs were clearly more effective on gram-positive bacteria (S. aureus and B. subtilis) than gram-negative bacteria (E. coli and P. aeruginosa). Thus, the mycosynthesized Fe₂O₃-NPs exhibited an ecofriendly, sustainable, and effective route for decolorization of navy blue and safranin dyes and antibacterial activity.

A novel route to the synthesis of α-Fe2O3@C@SiO2/TiO2 nanocomposite from the metal-organic framework as a photocatalyst for water treatment

In this study, an attempt was made to synthesize metal-organic frameworks (MOFs) based magnetic iron particles as photocatalysts for textile dye wastewater. Improvement strategy was a novel two-step dry method without using conventional methods to eliminate the consumption of chemical reagents. First, the heterogeneous photocatalyst of Fe-MOFs derived magnetic carbon nanocomposite with carboxylic acid surface functional groups (Fe@C-COOH) was achieved. Next, the α-Fe₂O₃@C@SiO₂/TiO₂ was successfully synthesized followed by a sol-gel method to coat the SiO₂ shell and a solvothermal method to coat the surface of the intermediate TiO₂ particles. The as-synthesized nanocomposite materials were characterized and physicochemical analytical equipment. Further, the investigation on magnetic photocatalytic nanocomposite α-Fe₂O₃@C@SiO₂/TiO₂ performance of dye degradation and photocatalytic activity on Reactive yellow 145 (RY145), using as an indicator was conducted. The as-synthesized nanocomposite particles were characterized using X-ray powder diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM), X-ray energy dispersive spectroscopy (EDX), and scanning electron microscopy (SEM) techniques. The structural characterization of the as-synthesized materials proved that these methods generate oxygen-containing functional groups, such as, -OH, -CO, and -COOH, which increases the polarity and hydrophilicity of the photocatalyst. The photocatalytic oxidation of RY145 dye under UVc light was discussed by the apparent first-order reaction rate and the kinetic model of the Langmuir-Hinshelwood followed a better fitting. The optimal performance of the composite is at pH = 2, 15 mg/100 mL of photocatalyst dose, 150 mg/L concentration of the dye RY145 at 25 °C temperature under UVc lamp irradiation for 90 min, and with the apparent reaction rate constant was 0.0165 min^-1. The thermodynamic analysis of activation parameters computed by the Eyring model and based on transition state theory (TST), an endothermic reaction with a positive value for Δ^‡H^o (50.16 kJ mol^-1) and a negative value for Δ^‡S^o (-153 J/mol K) both contribute toward achieving positive values for Δ^‡G^o and a nonspontaneous process. The proposed α-Fe₂O₃@C@SiO₂/TiO₂ demonstrated a high capability of photocatalytic degradation up to 97% after five successive cycles at the optimal condition compared to that of Fe₃O₄@C (18.74%) and Fe@C-COOH (77.9%) without reusability.

Degradation and detoxification of reactive yellow dyes by Scedosporium apiospermum: a mycoremedial approach

Textile industrial effluents have long enunciated the essentiality of ascertaining an efficient wastewater treatment for the removal of azo dyes given their potential disturbances on the ecosystem. Our study investigated the efficiency of the strain SKF2 among 14 other isolates, molecularly identified to be Scedosporium apiospermum, isolated by our research group from the textile effluent sludge in the degradation of two azo dyes, Reactive Yellow 145 and Remazol Yellow RR. Kinetic profiling of the degradation process revealed the decolourisation efficiency to be 94.8 and 86.9% for RY 145 and RYRR, respectively, during the declining growth phase. Laccase and polyphenol oxidase (RY 145-2.37 and RYRR-2.30 U/mL; RY 145-3.26 and RYRR-2.89 U/mL, respectively) were found to influence the biodegradation process in both the dyes than the other examined fungal degradative enzymes. The metabolic pathway predicted with the aid of GC-MS analysis identified the degraded metabolites to be smaller molecular weight non-toxic products. Assessment of toxicity via brine shrimp lethality assay (RY 145-23.3% and RYRR-16.7%, respectively) and seed germination assay (RY 145-96.7% and RYRR-83.3%) further solidified the detoxified status of both the dyes after biodegradation. The experimental data thus substantiated the expediency of S. apiospermum SKF2 in the degradation of textile azo dyes and its further employment in the bioremediation of textile wastewaters for agricultural applications and ecological recycling.

Aspergillus flavus-Mediated Green Synthesis of Silver Nanoparticles and Evaluation of Their Antibacterial, Anti-Candida, Acaricides, and Photocatalytic Activities

Aspergillus flavus F5 was used to reduce AgNO3 to form silver nanoparticles (Ag-NPs) that were monitored by a color change from colorless to yellowish-brown. The characterizations were achieved by UV-Vis spectroscopy, FT-IR, TEM, SEM-EDX, and XRD. Data showed that there was a successful formation of crystalline, spherical shape Ag-NPs with a particle average size of 12.5 ± 5.1 nm. The FT-IR clarified the role of various functional groups in the reducing/capping process. EDX-SEM revealed that the main component of the as-formed sample was set to be mainly Ag with a weight percentage of 46.1%. The synthesized Ag-NPs exhibit antibacterial and anti-Candida activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, C. glabrata, C. tropicalis, and C. parapsilosis, with inhibition zones ranging between 9.3 ± 0.5 to 20.8 ± 0.3 nm based on concentrations used and MIC values between 6.25 to 25 ppm. The mortality percentages of Tyrophagus putrescentiae mite species due to the mixing of their diet with different Ag-NPs concentrations of 0.5, 1.0, and 1.5 mg were 55.7 ± 2.1, 73.3 ± 1.5, and 87.4 ± 1.6% respectively after 20 days post-treatment. The catalytic activity of Ag-NPs to degrade methylene blue (MB) was investigated in the presence and absence of light irradiation. Data showed that a high photocatalytic degradation of MB compared with dark conditions at various times and concentrations. At a concentration of 70 mg/30 mL after 200 min., the dye removal percentages were 86.4 ± 0.4% in the presence of light irradiation versus 66.5 ± 1.1% in dark conditions.

Taguchi L25 (54) Approach for Methylene Blue Removal by Polyethylene Terephthalate Nanofiber-Multi-Walled Carbon Nanotube Composite

A membrane composed of polyethylene terephthalate nanofiber and multi-walled carbon nanotubes (PET NF-MWCNTs) composite is used to adsorb methylene blue (MB) dye from an aqueous solution. Scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction techniques are employed to study the surface properties of the adsorbent. Several parameters affecting dye adsorption (pH, MB dye initial concentration, PET NF-MWCNTs dose, and contact time) are optimized for optimal removal efficiency (R, %) by using the Taguchi L25 (54) Orthogonal Array approach. According to the ANOVA results, pH has the highest contributing percentage at 71.01%, suggesting it has the most significant impact on removal efficiency. The adsorbent dose is the second most affected (12.08%), followed by the MB dye initial concentration of 5.91%, and the least affected is the contact time (1.81%). In addition, experimental findings confirm that the Langmuir isotherm is well-fitted, suggesting a monolayer capping of MB dye on the PET-NF-MWCNT surface with a maximum adsorption capacity of 7.047 mg g−1. Also, the kinetic results are well-suited to the pseudo-second-order model. There is a good agreement between the calculated (qe) and experimental values for the pseudo-second-order kinetic model.

Carrier-Free Cross-linked Laccase Crystals for Biocatalytic Degradation of Textile Industrial Effluents

Herein, laccase from Trametes versicolor was used to fabricate carrier-free cross-linked laccase crystals (CLLCs) and deployed as a robust catalyst for waste effluent treatment. The surface morphology and involvement of functional group attributes of CLLCs were scrutinized by scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR). As fabricated CLLCs were subjected to kinetic characterization by assessing the effects of pH environment, thermal profile, and substrate (determination of K_m and V_max) on the activity. A fully characterized CLLCs fraction was used to treat synthetic dyes containing waste effluents taken from various industries, i.e., Chenab Textile Industry, M-tax, Sitara, and National Silk & Rayon Mills. Degradation profile revealed 36.8%, 27.6%, 39.9%, and 26.4% degradation of Chenab Textile Industry, M-tax, Sitara, and National Silk & Rayon Mills, respectively, by the free form of laccase, whereas the biocatalytic activity of CCLCs led to 78.6%, 75.6%, 85.5%, and 63.3% degradation of those effluents. The decrease in peak and mass region alongside the presence of new peaks in GC-MS affirms the effective decolorization of contaminated waste effluents. CLLCs retained over 70% and 50% of their degradation activity after 3 and 5 cycles, respectively. In conclusion, CLLCs might represent a robust bioprocess to improve the usability of laccase for various synthetic dyes containing waste effluents to diminish environmental pollution from the dye-based industries.

Photocatalytic Efficacy of Heterocyclic Base Grafted Chitosan Magnetite Nanoparticles on Sorption of Pb(II); Application on Mining Effluent

Development of bio-based sorbents (i.e., chitosan moieties) at nanoscale size for the removal of metal contaminants is the main target of this research. Grafting with thiazole heterocyclic derivative gives fast kinetics sorption, highly metal loading, and good recyclability for mining leaching solution. Different analyses tools including (thermogravimetric analysis (TGA), scanning electron microscope and energy dispersive spectroscopy (SEM-EDX), X-ray diffraction (XRD), Fourier transform infrared (FTIR), BET surface area (nitrogen sorption desorption), titration, and TEM (transmission electron microscopy)) were used to investigate the chemical and textural properties of the functionalized sorbent. The sorption was measured in normal visible light and under UV emission. The highest capacity was measured at pH 5, which reached 0.251 mmol Pb g−1 in visible light compared with 0.346 mmol Pb g−1 under UV for the pristine crosslinked chitosan (MCc). The sorption performances were improved by functionalization; (0.7814 and 1.014 mmol Pb g−1) for the functionalized sorbent (MCa-ATA) under visible light and UV, respectively. PFORE (pseudo-first-order rate equation) and RIDE (resistance to intraparticle diffusion) fit kinetics, the Sips equation is the most fit profile for the sorption isotherms for the MCc in either light and UV processes, while PFORE and RIDE for kinetics under light and UV for MCa-ATA and Sips in light and Sips and Langmuir under the UV emission. Finally, the sorbent was investigated toward a raffinate solution from ore processing and shows promising extraction tools for the most interesting elements.

Evaluate the Toxicity of Pyrethroid Insecticide Cypermethrin before and after Biodegradation by Lysinibacillus cresolivuorans Strain HIS7

Herein, bacterial isolate HIS7 was obtained from contaminated soil and exhibited high efficacy to degrade pyrethroid insecticide cypermethrin. The HIS7 isolate was identified as Lysinibacillus cresolivuorans based on its morphology and physiology characteristics as well as sequencing of 16S rRNA. The biodegradation percentages of 2500 ppm cypermethrin increased from 57.7% to 86.9% after optimizing the environmental factors at incubation condition (static), incubation period (8-days), temperature (35 °C), pH (7), inoculum volume (3%), and the addition of extra-carbon (glucose) and nitrogen source (NH₄Cl₂). In soil, L. cresolivuorans HIS7 exhibited a high potential to degrade cypermethrin, where the degradation percentage increased from 54.7 to 93.1% after 7 to 42 days, respectively. The qualitative analysis showed that the bacterial degradation of cypermethrin in the soil was time-dependent. The High-Performance Liquid Chromatography (HPLC) analysis of the soil extract showed one peak for control at retention time (R.T.) of 3.460 min and appeared three peaks after bacterial degradation at retention time (R.T.) of 2.510, 2.878, and 3.230 min. The Gas chromatography-mass spectrometry (GC-MS) analysis confirmed the successful degradation of cypermethrin by L. cresolivuorans in the soil. The toxicity of biodegraded products was assessed on the growth performance of Zea mays using seed germination and greenhouse experiment and in vitro cytotoxic effect against normal Vero cells. Data showed the toxicity of biodegraded products was noticeably decreased as compared with that of cypermethrin before degradation.

Safety Evaluation and Whole Genome Sequencing of Aspergillus japonicas PJ01 Reveal Its Potential to Degrade Citrus Segments in Juice Processing

Aspergillus japonicas PJ01 (A. japonicas PJ01) is a strain isolated from the rotten branches. In previ-ous studies, it was shown that it can produce complex enzymes to degrade polysaccharide com-ponents. In this study, we evaluated the safety of its crude enzyme solution. Acute oral toxicity, subchronic toxicity, micronucleus and sperm malformation tests all validated the high biologi-cal safety for the crude enzymes. Secondly, we carried out the citrus segment degradation ex-periment of crude enzyme solution. Compared with the control group, the crude enzyme solu-tion of A. japonicas PJ01 can completely degrade the segments in 50 min, which provides the basis for enzymatic peeling during juice processing. The whole genome sequencing showed that the genome of A. japonicus PJ01 has a GC content of 51.37% with a size of 36204647 bp, and encoded 10070 genes. GO, COG, KEGG and CAZy databases were used in gene annotation analyses. Pathway enrichment showed many genes related to carbohydrate metabolism, rich in genes re-lated to pectinase, xylanase and carboxylcellulase. Therefore, the complex enzyme produced by A. japonicus PJ01 can be used in gizzard juice processing to achieve efficient enzymatic decapsu-lation.

The Catalytic Activity of Biosynthesized Magnesium Oxide Nanoparticles (MgO-NPs) for Inhibiting the Growth of Pathogenic Microbes, Tanning Effluent Treatment, and Chromium Ion Removal

Magnesium oxide nanoparticles (MgO-NPs) were synthesized using the fungal strain Aspergillus terreus S1 to overcome the disadvantages of chemical and physical methods. The factors affecting the biosynthesis process were optimized as follows: concentration of Mg(NO3)2·6H2O precursor (3 mM), contact time (36 min), pH (8), and incubation temperature (35 °C). The characterization of biosynthesized MgO-NPs was accomplished using UV-vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy—energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), and dynamic light scattering (DLS). Data confirmed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with a size range of 8.0–38.0 nm at a maximum surface plasmon resonance of 280 nm. The biological activities of biosynthesized MgO-NPs including antimicrobial activity, biotreatment of tanning effluent, and chromium ion removal were investigated. The highest growth inhibition of pathogenic Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans was achieved at 200 μg mL–1 of MgO-NPs. The biosynthesized MgO-NPs exhibited high efficacy to decolorize the tanning effluent (96.8 ± 1.7% after 150 min at 1.0 µg mL–1) and greatly decrease chemical parameters including total suspended solids (TSS), total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and conductivity with percentages of 98.04, 98.3, 89.1, 97.2, and 97.7%, respectively. Further, the biosynthesized MgO-NPs showed a strong potential to remove chromium ions from the tanning effluent, from 835.3 mg L–1 to 21.0 mg L–1, with a removal percentage of 97.5%.

Rhizopus oryzae-Mediated Green Synthesis of Magnesium Oxide Nanoparticles (MgO-NPs): A Promising Tool for Antimicrobial, Mosquitocidal Action, and Tanning Effluent Treatment

The metabolites of the fungal strain Rhizopus oryaze were used as a biocatalyst for the green-synthesis of magnesium oxide nanoparticles (MgO-NPs). The production methodology was optimized to attain the maximum productivity as follows: 4 mM of precursor, at pH 8, incubation temperature of 35 °C, and reaction time of 36 h between metabolites and precursor. The as-formed MgO-NPs were characterized by UV-Vis spectroscopy, TEM, SEM-EDX, XRD, DLS, FT-IR, and XPS analyses. These analytical techniques proved to gain crystalline, homogenous, and well-dispersed spherical MgO-NPs with an average size of 20.38 ± 9.9 nm. The potentiality of MgO-NPs was dose- and time-dependent. The biogenic MgO-NPs was found to be a promising antimicrobial agent against the pathogens including Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans with inhibition zones of 10.6 ± 0.4, 11.5 ± 0.5, 13.7 ± 0.5, 14.3 ± 0.7, and 14.7 ± 0.6 mm, respectively, at 200 μg mL-1. Moreover, MgO-NPs manifested larvicidal and adult repellence activity against Culex pipiens at very low concentrations. The highest decolorization percentages of tanning effluents were 95.6 ± 1.6% at 100 µg/ 100 mL after 180 min. At this condition, the physicochemical parameters of tannery effluents, including TSS, TDS, BOD, COD, and conductivity were reduced with percentages of 97.9%, 98.2%, 87.8%, 95.9%, and 97.3%, respectively. Moreover, the chromium ion was adsorbed with percentages of 98.2% at optimum experimental conditions.

Harnessing Bacterial Endophytes for Promotion of Plant Growth and Biotechnological Applications: An Overview

Endophytic bacteria colonize plants and live inside them for part of or throughout their life without causing any harm or disease to their hosts. The symbiotic relationship improves the physiology, fitness, and metabolite profile of the plants, while the plants provide food and shelter for the bacteria. The bacteria-induced alterations of the plants offer many possibilities for biotechnological, medicinal, and agricultural applications. The endophytes promote plant growth and fitness through the production of phytohormones or biofertilizers, or by alleviating abiotic and biotic stress tolerance. Strengthening of the plant immune system and suppression of disease are associated with the production of novel antibiotics, secondary metabolites, siderophores, and fertilizers such as nitrogenous or other industrially interesting chemical compounds. Endophytic bacteria can be used for phytoremediation of environmental pollutants or the control of fungal diseases by the production of lytic enzymes such as chitinases and cellulases, and their huge host range allows a broad spectrum of applications to agriculturally and pharmaceutically interesting plant species. More recently, endophytic bacteria have also been used to produce nanoparticles for medical and industrial applications. This review highlights the biotechnological possibilities for bacterial endophyte applications and proposes future goals for their application.

Synthesis of Eco-Friendly Biopolymer, Alginate-Chitosan Composite to Adsorb the Heavy Metals, Cd(II) and Pb(II) from Contaminated Effluents

Efficient removal of Cd(II) and Pb(II) from contaminated water is considered a fundamental point of view. Synthetic hydrogel biopolymers based on chitosan and alginate (cost-effective and eco-friendly) were successfully designed and characterized by highly efficient removal contaminants. The sorbents are characterized by FTIR, SEM-EDX, TGA, XPS analyses and textural properties which are qualified by N₂ adsorption. The sorption properties are firstly investigated by the effect of pH, sorption isotherms, uptake kinetics, and selectivity from multi-metal solution with equi-molar concentration. The sorbent with 1:3 ratios (of chitosan and alginate respectively) is the most effective for metal removal (i.e., 0.81 mmol Cd g⁻¹ and 0.41 mmol Pb g⁻¹). Langmuir and Sip’s models fitted better the adsorption isotherms compared to the Freundlich model. Uptake kinetics was well fitted by pseudo-first-order rate equation, while the saturation was achieved within 40 min. The sorbent shows good reproducibility through duplicate the experiments with negligible decreasing efficiency (>2.5%). The sorbent was applied for water treatment on samples collected from the industrial area (i.e., 653 and 203 times over the MCL for Cd(II) and Pb(II) respectively according to WHO). The concentration of Cd and Pb was drastically decreased in the effluents as pH increased with removal efficiency up to 99% for both elements at pH 5.8 and SD equivalent 1 g L⁻¹ for 5 h.