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1.
Chemosphere ; 313: 137350, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36435317

RESUMO

There are numerous elements of daily life where plastic is employed, yet it is uncertain exactly when it will deteriorate. Poly-(3-hydroxybutyrate) (PHB), a biodegradable polymer, is viewed as a possible substitute for synthetic plastics made from petroleum. With Pseudomonas putida SS9, the current study sought to enhance operational conditions and nutritional factors to enhance PHB production. To maximize the impacts of operational factors, a combination of response surface modeling (RSM) and artificial neural networks (ANN) has been applied. PHB content was used as the response while the interaction effects of the factors were examined. The optimal parameters for PHB synthesis were further tested in a lab scale fermentor. Under optimal conditions, 13.83 g/L of C, 0.57 g/L of N, 0.59 g/L of P, the maximal productivity of PHB obtained with Pseudomonas putida SS9 is 12.89 g/L after 84 h. A mean square value of 15.7 with P < 0.0001 were obtained from the ANOVA results of quadratic polynomial model using RSM. The same construct was employed in MATLAB software to train a feed-forward ANN using the back-propagation approach, generating 12.88 g/L. The data indicated that a properly trained ANN model outperforms the RSM model in prediction. Furthermore, employing dairy waste (cheese whey) as a low-cost feedstock resulted in an equally proportionate PHB yield of 12.02 g/L. Therefore, cheese whey appeared to be a viable alternative carbon source over optimized synthetic media.


Assuntos
Pseudomonas putida , Hidroxibutiratos , Plásticos , Biopolímeros , Poliésteres
2.
Curr Drug Metab ; 21(3): 211-220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32316889

RESUMO

AIM AND OBJECTIVE: To review the applications and production studies of reported antileukemic drug L-glutaminase under Solid-state Fermentation (SSF). OVERVIEW: An amidohydrolase that gained economic importance because of its wide range of applications in the pharmaceutical industry, as well as the food industry, is L-glutaminase. The medical applications utilized it as an anti-tumor agent as well as an antiretroviral agent. L-glutaminase is employed in the food industry as an acrylamide degradation agent, as a flavor enhancer and for the synthesis of theanine. Another application includes its use in hybridoma technology as a biosensing agent. Because of its diverse applications, scientists are now focusing on enhancing the production and optimization of L-glutaminase from various sources by both Solid-state Fermentation (SSF) and submerged fermentation studies. Of both types of fermentation processes, SSF has gained importance because of its minimal cost and energy requirement. L-glutaminase can be produced by SSF from both bacteria and fungi. Single-factor studies, as well as multi-level optimization studies, were employed to enhance L-glutaminase production. It was concluded that L-glutaminase activity achieved by SSF was 1690 U/g using wheat bran and Bengal gram husk by applying feed-forward artificial neural network and genetic algorithm. The highest L-glutaminase activity achieved under SSF was 3300 U/gds from Bacillus sp., by mixture design. Purification and kinetics studies were also reported to find the molecular weight as well as the stability of L-glutaminase. CONCLUSION: The current review is focused on the production of L-glutaminase by SSF from both bacteria and fungi. It was concluded from reported literature that optimization studies enhanced L-glutaminase production. Researchers have also confirmed antileukemic and anti-tumor properties of the purified L-glutaminase on various cell lines.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Fermentação , Glutaminase/biossíntese , Glutaminase/farmacologia , Bactérias , Fungos , Humanos , Cinética
3.
Curr Drug Metab ; 21(1): 44-52, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32056519

RESUMO

Osteosarcoma is an aggressive bone cancer found in children and adolescents. The combined treatment strategy includes the surgical removal of tumour and subsequent chemotherapy to prevent the reoccurrence has been a widely accepted approach. However, the drug resistance developed by tumour cells causes recurrence of cancer. It is imperative to understand the molecular mechanism involved in the development of drug resistance and tumour progression for developing potential therapy. Tumour microenvironment and cellular cross-talk via activation of various signalling pathways are responsible for tumour progression and metastasis. The comprehensive reviews are already available on the tumour microenvironment, signalling cascades responsible for tumour progression, and cellular crosstalk between malignant cells and immune cells. Therefore, we intend to provide comprehend review postulating the importance of mesenchymal stem cells (MSCs) in osteosarcoma progression and metastasis. This paper is aimed to provide information sequentially includes: tumour microenvironment, MSCs role in osteosarcoma progression, the hypoxic environment in MSCs recruitment at the tumour site and the importance of exosomes in tumorigenesis, progression and metastasis. Overall, this review may enlighten the research on the role of MSCs and MSCs derived exosome in osteosarcoma progression and drug resistance. This possibly may result in developing novel therapeutic approaches to combat the osteosarcoma effectively and contributes for the development of prognosis tools for early diagnosis.


Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Células-Tronco/patologia , Microambiente Tumoral/fisiologia , Animais , Progressão da Doença , Humanos , Taxa de Sobrevida
4.
Curr Drug Metab ; 21(1): 11-24, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951174

RESUMO

L-glutaminase has versatile applications in pharma and food industries. In pharmaceutical industry, L-glutaminase can be used as anti-oxidant and anti-cancer agent to treat Acute Lymphocytic Leukaemia (ALL). Whereas, in the food industry, L-glutaminase is used for acrylamide degradation, theanine production, flavour enhancer, soy sauce and many. The other applications include nitrogen metabolism and its use as biosensor in hybridoma technology. Both intra-cellular and extra-cellular L-glutaminases from wide range of sources were identified. Because of its diverse applications, there is a need to improve the production of L-glutaminase by enzyme engineering technology. Effect of recombination on L-glutaminase production was also reported. Researchers also confirmed the antitumor properties of L-glutaminase by conducting in vitro, in vivo and in silico studies. Bacillus sps. and Aspergillus sps. are the commercial producers of L-glutaminase. In this review, the applications, different sources of Lglutaminase, anti-cancer properties were discussed.


Assuntos
Amidoidrolases/química , Glutaminase/química , Animais , Antineoplásicos/química , Indústria Farmacêutica/métodos , Aromatizantes/química , Indústria Alimentícia/métodos , Humanos
5.
Enzyme Microb Technol ; 117: 32-40, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30037549

RESUMO

Bioactive compounds from endophytes have been used to treat various diseases. In the present study, L-Asparaginase producing endophytes were isolated from Ocimum tenuiflorum (Tulasi) from NIT Warangal, Telangana, India to treat Acute Lymphoblastic Leukemia (ALL) in which L-Asparagine (L-Asn) deamination plays a vital role in ALL treatment. 20 (bacteria and fungi) out of 35 endophytes have been screened for L-Asparaginase production using rapid plate assay technique, in which four strains produced high amounts of L-Asparaginase. 16 s Ribosomal RNA sequencing studies were performed, Bacillus stratosphericus organism was identified, and purified L-Asparaginase sequence has been tailored using MALDI/TOF (Applied Biosystems). The homology model was developed by using MODELLER 9.15v as the endophyte lacks crystal structure of L-Asparaginase enzyme and validated by dint of quality index tools. Docking studies were performed using iGemdock 2.1v. In comparison, free energy binding efficiency of receptor towards L-Asparagine (L-Asn) is good with lesser energy -71.6 kcal/mol in comparison to L-Glutamine (L-Gln) having -67.7 kcal/mol. In order to find the stability of the docked complexes in dynamics environment, molecular dynamics and simulation studies were performed using GROMACS V4.6.5. The trajectory analysis for 10 ns shows the better RMSD, RMSF, Rg and average number of hydrogen bonds for complex 1 (L-Asparaginase + L-Asn docked complex). Hence, complex 1 was found to be more stable than Complex 2 (L-Asparaginase + L-Gln docked complex).


Assuntos
Asparaginase/química , Simulação por Computador , Endófitos/metabolismo , Simulação de Dinâmica Molecular , Ocimum sanctum/enzimologia , Asparaginase/isolamento & purificação , Asparaginase/metabolismo , Ligação de Hidrogênio , Software
6.
Sci Rep ; 7(1): 16413, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-29180764

RESUMO

Lead stands second among the deadly heavy metal pollutants owing to the incompetent mechanism possessed by the human body for its removal. A polymeric hydrogel in the form of composite was prepared using acrylic acid (monomer) and novel nanofiller that possess super adsorbent properties with restricted gel seepage into flowing ionic liquid. The filler used is an adsorbent which is biocompatible, biodegradable, economical, abundant, non-hazardous and easy to synthesize. The invariably porous nanofiller, the Nanobentonite(clay), was synthesized using ion exchange reaction by creating acidic environment for accelerated dispersion with exfoliation by CTAB to enhance cation exchange capacity. NanobentoFnite was capable of removing >97% lead ion in batch adsorption study and followed pseudo-second order kinetic model. Freundlich isotherm suggested a removal capacity of ~20 mg/g. Thus, the successfully experimented adsorbent was implicated as filler to form polyacrylic acid nanoclay hydrogel polymerized in ultrasonic bath. The amount of filler was varied from 0.25 to 2 wt% to get 94% removal, analyzed using ICP-OES. The prepared adsorbents were characterized before and after adsorption using TEM, FESEM, XRD, FTIR and DSC to understand the structural changes and metal-sorbent interaction. Thus, the novel nanosorbent/composite are promiscuous and competent in terms of availability, reusability and longevity to remove heavy metal ions.

7.
3 Biotech ; 7(3): 217, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28669076

RESUMO

Deep sea sediment samples of Bay of Bengal (Visakhapatnam) have been analyzed for actinomycetes as an elite source to screen for the production of bioactive metabolites. The actinomycetes strain VSM-30 has an exciting bioactivity profile and was isolated during our systemic screening of marine actinomycetes. It was identified as Streptomyces sparsus based on morphological, physiological, biochemical, and molecular approaches. Response surface methodology regression analysis was carried out to fit the experimental data of each response by the second-order polynomial. The results have proven right interaction among process variables at optimized values of incubation time at 12 days, pH at 8, temperature at 30 °C, concentrations of starch at 1%, and tryptone at 1% and the data have been adequately fitted into the second-order polynomial models. Under these conditions, the responses (zones of inhibition) of plant pathogenic fungi Aspergillus niger, Aspergillus flavus, Fusarium oxysporum, Fusarium solani, and Penicillium citrinum were also matched with experimental and predicted results. Chemotypic analysis of ethyl acetate extract of the strain was done using LC-Q-TOF-MS revealed the presence of bioactive compounds including tryptophan dehydrobutyrine diketopiperazine, maculosin, 7-o-demethyl albocycline, albocycline M-2, and 7-o-demethoxy-7-oxo albocycline in a negative ion mode. The ethyl acetate extract of actinobacterium has been subjected to gas chromatography and mass spectroscopy (GC-MS) revealed the presence of diverse compounds such as dotriacontane, tetracosane 11-decyl-, diheptyl phthalate, 1-hexadecanesulfonyl chloride, L-alanyl-L-tryptophan, phthalic acid ethyl pentyl ester, 4-trifluoroacetoxyhexadecane, and 1H-imidazole 4,5-dihydro-2,4-dimethyl. Hence, the ethyl acetate extract of Streptomyces sparsus VSM-30 may have antibacterial, antifungal, and antioxidant activities due to the presence of secondary metabolites in ethyl acetate extract. The study also supports marine sediment samples of Bay of Bengal, a promising marine ecosystem remained to be explored for new bioactive compounds.

8.
Prep Biochem Biotechnol ; 47(3): 219-228, 2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-27340934

RESUMO

The culture conditions and nutritional rations influencing the production of extra cellular antileukemic enzyme by novel Enterobacter aerogenes KCTC2190/MTCC111 were optimized in shake-flask culture. Process variables like pH, temperature, incubation time, carbon and nitrogen sources, inducer concentration, and inoculum size were taken into account. In the present study, finest enzyme activity achieved by traditional one variable at a time method was 7.6 IU/mL which was a 2.6-fold increase compared to the initial value. Further, the L-asparaginase production was optimized using response surface methodology, and validated experimental result at optimized process variables gave 18.35 IU/mL of L-asparaginase activity, which is 2.4-times higher than the traditional optimization approach. The study explored the E. aerogenes MTCC111 as a potent and potential bacterial source for high yield of antileukemic drug.


Assuntos
Antineoplásicos/metabolismo , Asparaginase/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Enterobacter aerogenes/enzimologia , Fermentação , Microbiologia Industrial/métodos , Asparagina/metabolismo , Carbono/metabolismo , Enterobacter aerogenes/metabolismo , Nitrogênio/metabolismo , Especificidade por Substrato , Temperatura
9.
3 Biotech ; 6(1): 2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28330072

RESUMO

Acute lymphocytic leukemia (ALL) is an outrageous disease worldwide. L-Asparagine (L-Asn) and L-Glutamine (L-Gln) deamination play a crucial role in ALL treatment. Role of Elspar® (L-asparaginase from Escherichia coli) in regulation of L-Asn and L-Gln has been confirmed by the other researchers through experimental studies. Therapeutic research against ALL remained elusive with the lack of information on molecular interactions of Elspar® with amino acid substrates. In the present study, using different docking tools binding cavities, key residues in binding and ligand binding mechanisms were identified. For the apo state enzyme and ligand bound state complexes, MD simulations were performed. Trajectory analysis for 30 ns run confirmed the kinship of L-Asn with L-asparaginase enzyme in the dynamic system with less stability in comparison to L-Gln docked complex. Overall findings strongly supported the bi-functional nature of the enzyme drug. A good number of conformational changes were observed with 1NNS structure due to ligand binding. Results of present study give much more information on structural and functional aspects of E. coli L-asparaginase upon the interaction with its ligands which may be useful in designing effective therapeutics for ALL.

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