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1.
Water Environ Res ; 96(1): e10959, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38204323

RESUMO

The contamination of wastewater with textile dyes has emerged as a pressing environmental concern due to its persistent nature and harmful effects on ecosystems. Conventional dye treatment methods have proven inadequate in effectively breaking down complex dye molecules. However, a promising alternative for textile dye degradation lies in the utilization of white rot fungi, renowned for their remarkable lignin-degrading capabilities. This review provides a comprehensive analysis of the potential of white rot fungi in degrading textile dyes, with a particular focus on their ligninolytic enzymes, specifically examining the roles of lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase in the degradation of lignin and their applications in textile dye degradation. The primary objective of this paper is to elucidate the enzymatic mechanisms involved in dye degradation, with a spotlight on recent research advancements in this field. Additionally, the review explores factors influencing enzyme production, including culture conditions and genetic engineering approaches. The challenges associated with implementing white rot fungi and their ligninolytic enzymes in textile dye degradation processes are also thoroughly examined. Textile dye contamination poses a significant environmental threat due to its resistance to conventional treatment methods. White rot fungi, known for their ligninolytic capabilities, offer an innovative approach to address this issue. The review delves into the intricate mechanisms through which white rot fungi and their enzymes, including LiP, MnP, and laccase, break down complex dye molecules. These enzymes play a pivotal role in lignin degradation, a process that can be adapted for textile dye removal. The review also emphasizes recent developments in this field, shedding light on the latest findings and innovations. It discusses how culture conditions and genetic engineering techniques can influence the production of these crucial enzymes, potentially enhancing their efficiency in textile dye degradation. This highlights the potential for tailored enzyme production to address specific dye contaminants effectively. The paper also confronts the challenges associated with integrating white rot fungi and their ligninolytic enzymes into practical textile dye degradation processes. These challenges encompass issues like scalability, cost-effectiveness, and regulatory hurdles. By acknowledging these obstacles, the review aims to pave the way for practical and sustainable applications of white rot fungi in wastewater treatment. In conclusion, this comprehensive review offers valuable insights into how white rot fungi and their ligninolytic enzymes can provide a sustainable solution to the urgent problem of textile dye-contaminated wastewater. It underscores the enzymatic mechanisms at play, recent research breakthroughs, and the potential of genetic engineering to optimize enzyme production. By addressing the challenges of implementation, this review contributes to the ongoing efforts to mitigate the environmental impact of textile dye pollution. PRACTITIONER POINTS: Ligninolytic enzymes from white rot fungi, like LiP, MnP, and laccase, are crucial for degrading textile dyes. Different dyes and enzymatic mechanisms is vital for effective wastewater treatment. Combine white rot fungi-based strategies with mediator systems, co-culturing, or sequential treatment approaches to enhance overall degradation efficiency. Emphasize the broader environmental impact of textile dye pollution and position white rot fungi as a promising avenue for contributing to mitigation efforts. This aligns with the overarching goal of sustainable wastewater treatment practices and environmental conservation. Consider scalability, cost-effectiveness, and regulatory compliance to pave the way for sustainable applications that can effectively mitigate the environmental impact of textile dye pollution.


Assuntos
Ecossistema , Lacase , Lignina , Águas Residuárias , Corantes , Têxteis , Fungos
2.
Environ Geochem Health ; 46(2): 57, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273049

RESUMO

The presence of fluoride and nitrate is a serious groundwater quality issue in India impacting human health. In the present study, 14 different hydrochemical parameters for 76 groundwater samples collected from the Jajpur district of Odisha, India, were evaluated. Entropy-weighted water quality index (EWQI), fixed-weight groundwater quality index (GWQI), principal component analysis (PCA), and rotated factor loading-based water quality index (PCWQI) were employed to assess groundwater quality. About 65.79 ± 4.68%, 33.55 ± 3.95%, and 0.66 ± 0.76% of the samples were rated as "excellent," "good," or "medium" quality, respectively, across the four different water quality indices, with a nominal rating discrepancy of 13.15%. Though 86% of samples consistently received excellent or good ratings across all WQI frameworks, concentrations of F- and NO3- in 36.8% and 11.84% of the samples exceeded the WHO permissible limit. In health risk assessment, about 38.15% of samples surpassed the F- hazard quotient (HQ > 1) posing non-carcinogenic health risks for children. The non-carcinogenic health risks due to NO3- were evident in 55.26% and 11.84% of samples for children and adults, respectively. The higher concentration of NO3- in some of the water samples, together with its positive correlation with HCO3-, may worsen groundwater pollution. The moderate correlation between Ca2+ and HCO3- (r = 0.410) and the insignificant correlation between Mg2+ and HCO3- (r = 0.234) suggests calcite dissolution is far more common than dolomite.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Criança , Adulto , Humanos , Monitoramento Ambiental , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Qualidade da Água , Água Subterrânea/análise , Fluoretos/análise , Índia , Medição de Risco
3.
Microb Pathog ; 188: 106514, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38296118

RESUMO

Dental caries predominantly attributed to the cariogenic nature of Streptococcus mutans, continue to pose a substantial global challenge to oral health. In response to this challenge, this study aimed to evaluate the effectiveness of leaf extracts (LEs) and essential oils (EOs) derived from different medicinal plants in inhibiting the growth of Streptococcus mutans biofilm. In vitro and in silico approaches were employed to identify active compounds and assess their inhibitory effects on S. mutans. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were measured to determine the anti-biofilm and anti-adherence activity against S. mutans. Biofilm viability (CFU/mL) and extracellular polymeric substance (EPS) concentration were quantified. GC-MS analysis was utilized to identify active compounds in the most effective plant extracts exhibiting anti-S. mutans activity. A high-throughput screening focused on the interaction between these compounds and the target enzyme SortaseA (SrtA) using molecular docking was performed. Results indicated that Cymbopogon citratus displayed the highest efficacy in reducing S. mutans biofilm formation and adhesion activity, achieving 90 % inhibition at an MIC value of 12 µg/mL. Among the 12 bioactive compounds identified, trans-Carvyl acetate exhibited the lowest binding energy with SrtA (-6.0 Kcal/mole). Trans-Carvyl acetate also displayed favorable pharmacokinetic properties. This study provides novel insights into the anti-S. mutans properties of C. citratus and suggests its potential as a therapeutic approach for oral health. Further research is needed to explore the combined effect of plant extracts for enhanced protection against dental caries.


Assuntos
Cárie Dentária , Streptococcus mutans , Humanos , Saúde Bucal , Matriz Extracelular de Substâncias Poliméricas , Cárie Dentária/prevenção & controle , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Biofilmes , Acetatos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
4.
Oral Dis ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37870077

RESUMO

OBJECTIVE: Glucosyltransferases (Gtfs) and quorum sensing (QS) mediated transduction genes play critical roles in the pathogenesis of Streptococcus mutan-mediated dental caries. Therefore, targeting gtfs and QS-mediated virulence genes have therefore emerged as an intriguing goal for efficient therapeutic approaches that block cariogenic biofilms. METHODS: Post-biotic mediators (PMs) obtained from our previously isolated and characterized beneficial bacteria Enterobacter colacae PS-74 was assessed for its antibiofilm potential against S. mutans. According to the transcriptome method, qRT-PCR analysis was performed against virulence genes. For microscopic visualization, SEM and CLSM analyses were used to confirm the inhibitory effects of PMs. RESULTS: PMs dramatically reduced the expression of QS signal transduction, glucan metabolism, and biofilm-regulated genes such gtfB, gtfC, ComDE, VicR, brpA in S. mutans, which validates the outcomes of in vitro result. Their unique metabolites may help to control biofilm formation by eluding antimicrobial resistance. CONCLUSION: Considering the above findings, PMs may deem to be an innovative, alluring, and secure method for preventing dental caries due to their biological activity. Our study unravels the inhibitory effect of PMs, which will contribute to instruct drug design strategies for effective inhibition of S. mutans biofilms.

5.
Mol Divers ; 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37395840

RESUMO

Cancer is a challenging and second most deadly disease. The epidermal growth factor receptors (EGFRs) dimerize upon ligand bindings to the extracellular domain that intiates the downstream signaling cascades and activates intracellular kinase domain. Thus, activation of autophosphrylation through kinase domain results in metastasis, cell proliferation, and angiogenesis. In this study, we unravel the binding mechanism of newly synthesized thiazolo-[2,3-b] quinazolin-6-one and evaluate their anti-cancer activity against ovary and prostate carcinoma cell lines (OVCAR-3 and PC-3). Synthesized molecules exhibited promising anti-cancer activity against OVCAR-3 and PC-3 carcinoma cell lines with inhibitory concentrations ranging from 13.4 ± 0.43 to 23.6 ± 1.22 µM and 7.5 ± 0.62 to 67.5 ± 1.24 µM, respectively. These compounds induced apoptosis and resulted in cell cycle arrest at G1 and G2/M transition phases. Next, the nude mice models were taken to investigate the toxicity of the 4bi compound, and in vivo investigations revealed no effects upon examined organs (liver and kidney) treated at different concentrations. Moreover, the combined in silico approaches, molecular docking, molecular dynamics simulations, and MM/PBSA methods were performed to assess the binding affinity and stability of bioinspired synthesized congeners with the epidermal growth factor receptor tyrosine kinase (EGFR-TK). The free binding energy (ΔGbind) of the 4bi molecule was found comparable to Erlotinib drug. The test molecule could be competent for further usage to determine its efficicacy in cancer therapeutics.

6.
Heliyon ; 9(7): e17509, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37449169

RESUMO

To commercialize functional foods, probiotics must exhibit high resistance and acceptable stability under various unfavorable conditions to maintain the quality of fruit juices. This study will provide an insight into fortification of orange juice with a plant probiotic Kocuria flava Y4 by microencapsulation. Therefore, this study investigated the colony release, physicochemical and phytochemical parameters, and antioxidant activity of the orange juice exposed to microencapsulated probiotics and the one without probiotics (control). Evaluation of orange juice on the growth of probiotic bacteria showed that the fortification with alginate and psyllium micro-particles showed highest encapsulation efficiency (99.01%) and acceptable viability of probiotic cells (8.12 ± 0.077 CFU/mL) during five weeks storage at 4 °C. The morphology and functional properties of beads was studied by SEM, Zeta-potential and FTIR analysis. The sucrose and organic acids concentrations decreased significantly during fortification period (0-72 h) except ascorbic acid. Furthermore, glucose, pH, acidity, TSS were maintained. The results affirm the suitability and feasibility of developing a plant probiotic beverage using orange juice by encapsulation method.

7.
Biotechnol Appl Biochem ; 70(6): 1915-1924, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37417692

RESUMO

Health and environmental consequences are unavoidable when it comes to management of hospital waste (HW) disposables. In order to eradicate the HW, this study isolated a novel fungus SPF21 from a hospital dumping yard to degrade Polypropylene (PP). We measured the attributes of PP inoculated with fungus using mass loss, Fourier trans-form infrared (FTIR), contact angle (CA), and scanning electron microscopy (SEM). The weight of PP exposed to SPF21 was reduced by 25% in 90 days. The SEM images reveal that there are pores all over the sample surface; they alsocaused voids during the biodegradation of PP. FTIR analysis indicates that the spectra of treated mask pieces show the absence of peak at 1746 cm-1 and the appearance of a new peak at 1643 cm-1 . A period of 90-day exposure to the fungal isolate SPF21 reduced the CA of PP by 44.8% when compared to the nonexposed PP samples, suggesting that the surface of PP turned more hydrophilic after exposure. Moreover, our study on PP degradation by the fungus Ascotricha sinuosa SPF21 appears to be promising from the perspective of environmental, health, and economic hazards. Our results indicate that biodegradation greatly facilitates fungus deposition and changes PP film morphology and hydrophilicity.


Assuntos
Fungos , Polipropilenos , Polipropilenos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura , Biodegradação Ambiental , Fungos/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-37126112

RESUMO

Phenolic compounds are the major contaminants identified from various industrial effluents, which pose an extreme threat to the environment. Therefore, investigating an effective technique to remove these toxic phenolic compounds from the contaminated environment is very essential. In the present investigation, batch tests were performed to assess the biodegradation of phenol using an indigenous Rhodococcus pyridinivorans strain PDB9T NS-1 encapsulated in a calcium alginate bead system. In order to improve the mechanical stability, silica was added to the cell-embedded Ca-alginate beads. The impact of experimental conditions such as contact time, pH, and initial phenol doses was investigated. The biodegradation of phenol was examined over a wide range of phenol, and the results showed that more than 99.6% degradation was achieved at an initial phenol dose of 1000 mg/L in 70 h at 30 °C. Among the various sorption isotherm tested, the Freundlich isotherm was the best fitted to the experimental data. This behavior indicated a multilayer biosorption process and was controlled by heterogeneous surface energy. Based on an intra-particle diffusion model, internal mass transfer or pore diffusion predominated over exterior mass transfer in controlling the entire phenol biosorption process. The biosorption of phenol onto the cell encapsulated in the Ca-alginate bead follows pseudo-first-order kinetics with a superior phenol biosorption capacity of 155 mg/g of Ca-alginate. Further stability study revealed that the bead could be recycled successfully without any substantial decline in phenol degradation efficiency, indicating that the immobilized microbe possesses exceptional operating stability.

9.
Biotechnol Appl Biochem ; 70(4): 1518-1529, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37232000

RESUMO

Streptococcus mutans plays a major role in biofilm formation and pathogenic bacterial adhesion. Here we investigated the abilities of our isolates from diverse conventional sources to characterize the beneficial bacteria for inhibition of S. mutans. Enterobacter cloacae PS-74, a beneficial bacteria isolated from yoghurt, is gram negative, rod shaped, and resistant to acid, bile salt, and amylase. PS-74 cell-free supernatants (CFS) demonstrated highest zone of inhibition of 29 ± 1.7 mm. Further, the minimum inhibitory concentration (MIC) value of CFS PS-74 was recorded to be 10 µL and its minimum bactericidal concentration (MBC) value was found to be 15µL which led to 99.9% log reduction of S. mutans. Moreover, the biofilm formation was reduced by 84.91% at MIC15 of CFS PS-74 which alleviate the dental caries formation by S. mutans. This is the first report on E. cloacae PS-74, which was studied for its probiotic properties to inhibit S. mutans MTCC-890 due to the production of organic acids and employed in oral treatment.


Assuntos
Cárie Dentária , Probióticos , Humanos , Biofilmes , Cárie Dentária/tratamento farmacológico , Cárie Dentária/prevenção & controle , Streptococcus mutans , Probióticos/farmacologia
10.
BioTechnologia (Pozn) ; 104(1): 85-91, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37064274

RESUMO

The discharge of wastewater from textile industries into aquatic bodies has severe health and environmental impacts. Textile industries generate huge amounts of effluents containing hazardous toxic dyes. Anthraquinone (AQ) dyes containing AQ chromophore groups are the second most important class of nondegradable textile dyes, preceded by azo dyes. Despite their prevalence, biodegradation of AQ dyes has not yet been completely understood because of their complex and stable structures. Currently, microbiological approaches to treating dyeing wastewater are considered economical and feasible, and reports regarding fungal degradation of AQ dyes are increasing. Structures and classification of AQ dyes were summarized in this study along with degradative fungi, and their enzyme systems with influencing factors and possible mechanisms of AQ mycoremediation were explored. Furthermore, the existing problems and present research progress were discussed. Finally, the key points with future research directions were presented.

11.
Probiotics Antimicrob Proteins ; 15(3): 614-629, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34825308

RESUMO

This aim of the study was to isolate and screen potential probiotics from Dioscorea villosa leaves. The potential isolate Y4 was obtained from the Dioscorea villosa leaves, and its ability to grow in a medium containing high NaCl concentrations (2-10%) indicated its negative hemolytic activity. Furthermore, Y4 demonstrated inhibitory activity against human pathogens, such as Klebsiella pneumonia, Staphylococcus aureus, Citrobacter koseri, and Vibrio cholerae, as well as towards a plant pathogen isolate OR-2 (obtained from Citrus sinensis). Some biologically important functional groups of Y4 metabolites, such as sulfoxide; aliphatic ether; 1, 2, 3-trisubstituted, tertiary alcohol: vinyl ether; aromatic amine; carboxylic acid; nitro compound; alkene mono-substituted; and alcohol, were identified through FTIR analysis. The 16S rRNA sequencing and subsequent phylogenetic tree analysis indicated that Y4 and OR-2 are the closest neighbors to Kocuria flava (GenBank accession no. MT773277) and Pantoea dispersa (GenBank accession no. MT766308), respectively. The potential isolate Y4 was found to exhibit adhesion, auto-aggregation, co-aggregation, and weak biofilm activity. It also exhibited a high level of antimicrobial activity and antibiotic susceptibility. The safety of K. flava Y4 isolate, which is proposed to be a probiotic, was evaluated through acute oral toxicity test and biogenic amine production test. Moreover, the preservation potential of isolate Y4 was assessed through application on fruits under different temperatures. Thus, our results confirmed that Kocuria flava Y4 is a prospective probiotic and could also be used for the preservation of fruits.


Assuntos
Dioscorea , Probióticos , Humanos , Dioscorea/genética , Filogenia , RNA Ribossômico 16S/genética , Estudos Prospectivos , Probióticos/farmacologia
12.
Int J Anal Chem ; 2022: 6403090, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35169395

RESUMO

The exogenous lipolytic activities of Kocuria sp. have been recognized earlier but the genus further contains many more unexplored strains. In this study, the extracellular lipase activity of Kocuria flava Y4 (GenBank accession no. MT773277), isolated from Dioscorea villosa during our previous study, was regulated by different physicochemical parameters, such as pH, temperature, shaking speed, and incubation time. For efficient immobilization of the extracellular lipase, 4% sodium alginate, 50 mL of 25 nM CaCl2.2H2O solution, and 15 min. Hardening time of gel beads in calcium chloride was used. For the first time, K. flava Y4 lipase was purified using ammonium sulphate precipitation followed by dialysis and DEAE-Sepharose anion exchange chromatography with Sepharose-6B gel filtration chromatography, yielding ∼15-fold purified lipase with a final yield of 96 U/mL. The SDS-PAGE of purified lipase displayed a single strong band, indicating a monomeric protein of 45 kDa. At a temperature of 35°C and pH 8, the purified lipase showed maximum hydrolytic activity. Using p-nitrophenyl acetate (p-NPA) as the hydrolysis substrate, the values of K m and V max derived from the Lineweaver-Burk plot were 4.625 mM and 125 mol/min-1mg-1, respectively.

13.
Ecotoxicology ; 31(4): 602-614, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35059927

RESUMO

Brominated phenols are listed as priority pollutants together with nitrophenol and chlorophenol are the key components of paper pulp wastewater. However, the biodegradation of bromophenol in a mixed substrate system is very scanty. In the present investigation, simultaneous biodegradation kinetics of three substituted phenols 4-bromophenol (4-BP), 4-nitrophenol (4-NP), and 4-chlorophenol (4-CP) were investigated using Arthrobacter chlorophenolicus A6. A 23 full factorial design was applied with varying 4-BP and 4-CP from 75-125 mg/L and 4-NP from 50-100 mg/L. Almost complete degradation of this mixture of substituted phenols was achieved at initial concentration combinations of 125, 125, and 100 mg/L of 4-CP, 4-BP, and 4-NP, respectively, in 68 h. Statistical analysis of the results revealed that, among the three variables, 4-NP had the most prominent influence on the degradation of both 4-CP and 4-BP, while the concentration of 4-CP had a strong negative interaction effect on the biodegradation of 4-NP. Irrespective of the concentration levels of these three substrates, 4-NP was preferentially biodegraded over 4-CP and 4-BP. Furthermore, 4-BP biodegradation rates were found to be higher than those of 4-CP, followed by 4-NP. Besides, the variation of the biomass yield coefficient of the culture was investigated at different initial concentration combinations of these substituted phenols. Although the actinomycetes consumed 4-NP at a faster rate, the biomass yield was very poor. This revealed that the microbial cells were more stressed when grown on 4-NP compared to 4-BP and 4-CP. Overall, this study revealed the potential of A. chlorophenolicus A6 for the degradation of 4-BP in mixed substrate systems.


Assuntos
Arthrobacter , Poluentes Ambientais , Arthrobacter/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/metabolismo , Micrococcaceae , Fenóis
14.
Sci Rep ; 11(1): 15978, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354096

RESUMO

Globally, textile industries are one of the major sectors releasing dye pollutants. This is the first report on the positive correlation between toxicity and chemical oxygen demand (COD) of textile effluent along with the proposed pathway for enzymatic degradation of acid orange 10 using Geotrichum candidum within a very short stretch of time (18 h). Removal efficiency of this mycoremedial approach after 18 h in terms of chemical oxygen demand, biological oxygen demand, total suspended solids, salinity, color and dye concentration in the treated effluent reached to 98.5%, 56.3%,73.2%, 64%, 89% and 87% respectively. Also there was a decrease in pH of the treated effluent. FTIR analysis of the treated effluent confirmed biodegradation. The LCMS analysis showed the degradation of acid orange 10, which was confirmed by the formation of two biodegradation products, 7-oxo-8-iminonapthalene-1,3-disulfonate and nitrosobenzene, which subsequently undergoes stepwise hydrogenation and dehydration to form aniline via phenyl hydroxyl amine as intermediate. The X-ray diffraction studies showed that heavy metal content in the treated effluent has reduced along with decrease in % crystallinity, indicating biodegradation. The connection between toxicity and COD was also inveterated using Pearson's correlation coefficient. Further the toxicological studies indicated the toxicity of raw textile effluent and relatively lower toxic nature of metabolites generated after biodegradation by G. candidum.

15.
BioTechnologia (Pozn) ; 102(4): 445-455, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36605603

RESUMO

Currently, globalization, urbanization and industrialization have led to several environmental issues. In many industries, particularly in textile industries, the extensive use of synthetic dyes has increased. Dye is an integral element used to impart color to textile materials. Wastes generated during the processing and treatment of the dye contain inorganic and organic compounds that are hazardous, thereby posing a serious threat to the ecosystem. It is therefore important to implement cost-efficient and successful measures against these emissions in order to preserve habitats and natural resources. In this context, biodegradation by fungi or mycoremediation of dyes using potential fungi is a fairly inexpensive and environmental friendly method for decomposing or mineralizing barely or less decaying dye compounds. Fungi play a crucial role in degrading and decolorizing organic dyes by enzymes and processes such as absorption, adsorption and aggregation of effluent colorants. The factors affecting the decolorization and biodegradation of dye compounds through fungal bioremediation, such as pH, temperature, dye concentration, agitation, effects of carbon and nitrogen sources, dye structure, enzymes, electron donor and redox mediators are discussed in this review. The review also includes a summary on the mechanism and kinetics of dye degradation as well as recent advances and future perspectives in mycoremediation of dyes.

16.
Indian J Microbiol ; 55(3): 258-68, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26063935

RESUMO

ABSTRACT: In the present study, artificial neural network (ANN) modelling coupled with particle swarm optimization (PSO) algorithm was used to optimize the process variables for enhanced low density polyethylene (LDPE) degradation by Curvularia lunata SG1. In the non-linear ANN model, temperature, pH, contact time and agitation were used as input variables and polyethylene bio-degradation as the output variable. Further, on application of PSO to the ANN model, the optimum values of the process parameters were as follows: pH = 7.6, temperature = 37.97 °C, agitation rate = 190.48 rpm and incubation time = 261.95 days. A comparison between the model results and experimental data gave a high correlation coefficient ([Formula: see text]). Significant enhancement of LDPE bio-degradation using C. lunata SG1by about 48 % was achieved under optimum conditions. Thus, the novelty of the work lies in the application of combination of ANN-PSO as optimization strategy to enhance the bio-degradation of LDPE.

17.
Jundishapur J Microbiol ; 7(12): e11800, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25741425

RESUMO

BACKGROUND: Amylases play a vital role in biotechnological studies and rank an important position in the world enzyme market (25% to 33%). Bioprocess method of amylase production is more effective than the other sources, since the technique is easy, cost effective, fast, and the enzymes of required properties can be procured. OBJECTIVES: The current study aimed to report the characteristics of novel amylase producing bacterial strains isolated from Taptapani hot spring, Odisha, India. MATERIALS AND METHODS: Bacterial strains were isolated by dilution plating method from the water samples collected from Taptapani Hot Spring, Odisha and screened for amylase production through starch hydrolysis. The bacterial isolates were identified morphologically, biochemically, and finally by 16S rDNA profiling. RESULTS: Based on the morphological, physiological, biochemical characteristics and the molecular characterization, the isolates SS1, SS2, and SS3 were identified as Bacillus barbaricus, Aeromonas veroni, and Stenotrophomonas maltophilia, respectively. The approximate molecular weight of enzymes from SS1, SS2, and SS3 strains were 19 kDa, 56 kDa and 49 kDa, respectively. CONCLUSIONS: The current report isolates, characterizes, and demonstrates the novel heat-adapted amylase-producing bacteria SS1, SS2 and SS3 from Taptapani hot spring, indicating its potentiality and stability under acidic conditions.

18.
J Hazard Mater ; 265: 47-60, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-24333714

RESUMO

In the present investigation, a number of experiments have been conducted to isolate microbial strains from Taptapani Hot Spring Odisha, India for bioremediation of cadmium and lead. The strains Stenotrophomonas maltophilia (SS1), Aeromonas veronii (SS2) and Bacillus barbaricus (SS3) have shown better adaptation to metal tolerance test, with different concentrations of cadmium and lead and hence have been selected for further studies of metal microbial interaction and optimization. The results of bioremediation process indicate that consortium of thermophilic isolates adsorbed heavy metals more effectively than the individually treated isolates. Therefore, A 24 full factorial central composite design has been employed to analyze the effect of metal ion concentration, microbial concentration and time on removal of heavy metals with consortium. Analysis of variance (ANOVA) shows a high coefficient of determination value. The kinetic data have been fitted to pseudo-first order and second-order models. The isotherm equilibrium data have been well fitted by the Langmuir and Freundlich models. The optimum removal conditions determined for initial ion concentration was 0.3g/l; contact time 72h; microbial concentration, 3ml/l; and pH 7. At optimum adsorption conditions, the adsorption of cadmium and lead are found to be 92% and 93%, respectively, and presence of metals was confirmed through EDS analysis.


Assuntos
Bactérias/química , Cádmio/química , Fontes Termais/microbiologia , Chumbo/química , Poluentes Químicos da Água/química , Adsorção , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , DNA Bacteriano/genética , DNA Ribossômico/genética , Índia , Modelos Teóricos , Águas Residuárias , Microbiologia da Água
19.
Bioinformation ; 8(7): 326-30, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22553390

RESUMO

Bacterial samples isolated from the upper respiratory tract of a healthy broiler chicken and a wild chicken suffering from influenza which were collected locally revealed proteolytic activity as detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis. Among five protease producing strains screened, one was selected as promising protease producer. The activity of the protease produced by this organism is stable up to 620C. Optimum yield was achieved after 19 hours of culture, at pH 9.0 and 450C. The desired protein was precipitated from the crude extract by using ammonium sulfate (60%) followed by dialysis and purified by Ion-exchange chromatography. Further investigations are needed to know about the structure elucidation of the purified protein for industrial exploitation.

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