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1.
Chemosphere ; 354: 141690, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484988

RESUMO

In the present study, the northwest coast of India, bordering the Arabian Sea, was selected to evaluate the microplastic (MP) abundance. This is the first study to emphasize the effects of different seasons on MP distribution. The collected MPs were dried, segregated, and evaluated based on their morphotype, size, color, and polymer type. A total of 1756.6, 7326.6, and 202 particles/kg of sand were estimated in the pre-monsoon, monsoon and post-monsoon seasons, respectively, with a dominance of polypropylene (PP) type of plastic in the pre-monsoon and high-density polyethylene (HDPE) in monsoon and post-monsoon seasons. HDPE and PP collected MPs during the monsoon season were further characterized for associated contaminants. Metal absorbance was detected using SEM-EDX mapping and ICP-MS. The presence of organic compounds (OCs) was analyzed using GC-MS. MPs exhibit distinct associations with metals, among which the HDPE pellet morphotype exhibits a higher range of metal adsorption. Total 61 different OCs were associated with MPs. The HDPE pellets contained the highest amounts of hydrophobic organic compounds. PP pellets were found to contain triglycerides, fatty aldehydes, and alkaloids, along with HOCs. Among morphotypes, pellet forms of MPs were found to adsorb more contaminants. These co-contaminants infiltrate the study area through sewage runoff and shoreline debris deposition, subsequently interacting with MPs. Furthermore, the MP diversity was studied by employing the MP diversity integrated index, which suggests that most of the MP diversity was observed in the pre-monsoon period. The pollution load index employed an MP risk assessment, which presented a low degree of MP contamination. In contrast, the polymer hazard index was calculated as 21650.3 in post-monsoon, placing the area under the extreme danger category. It is evident from the data that the types of MP is more important than their number. Thus, MP morphotypes have importance in the adsorption of co-contaminants.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/química , Estações do Ano , Polietileno , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polipropilenos , Índia
2.
Food Chem ; 428: 136746, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37421667

RESUMO

Deep-fat frying of food develops lipid oxidation products that deteriorate oil and pose a health risk. This necessitates the development of a rapid and accurate oil quality and safety detection technique. Herein, surface-enhanced Raman spectroscopy (SERS) and sophisticated chemometric techniques were used for rapid and label-free determination of peroxide value (PV) and fatty acid composition of oil in-situ. In the study, plasmon-tuned and biocompatible Ag@Au core-shell nanoparticle-based SERS substrates were used to obtain optimum enhancement despite matrix interference to efficiently detect the oil components. The potent combination of SERS and the Artificial Neural Network (ANN) method could determine the fatty acid profile and PV with upto 99% accuracy. Moreover, the SERS-ANN method could quantify the low level of trans fats, i.e., < 2%, with 97% accuracy. Therefore, the developed algorithm-assisted SERS system enabled the sleek and rapid monitoring and on-site detection of oil oxidation.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Análise Espectral Raman/métodos , Ácidos Graxos , Oxirredução , Algoritmos , Nanopartículas Metálicas/química
3.
Microbiol Resour Announc ; 11(5): e0009622, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35435742

RESUMO

The draft genome sequence of Exiguobacterium sp. strain TBG-PICH-001, isolated from Pichavaram Mangrove Forest (Tamil Nadu, India), is reported here. Paired-end sequencing technology was used to sequence the genome on the Illumina HiSeq X Ten platform. The genome comprises 3,141,454 bp; it harbors 3,154 genes and has a G+C content of 47.34%.

4.
Phytomed Plus ; 2(2): 100241, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35403092

RESUMO

Background: Over million people have been infected with SARS-CoV-2 virus worldwide, with around 3% reported deaths till date. A few conventional antiviral treatments have been tried to mitigate the coronavirus. However, many alternative therapeutics are being evaluated worldwide. In the present study, we investigated traditional Indian medicinal compounds antiviral potencies as an effective drug for targeting SARS-CoV-2E. SARS-CoV-2 E protein plays a key role in coronavirus life cycle and is an interesting target for the development of anti-SARS-CoV-2 E drugs. Methods: Molecular docking studies of medicinal compounds possessing wide range of pharmacological and antiviral activities against enveloped viruses were evaluated with the computer-aided drug design screening software; PyRx. Twelve medicinal compounds isolated from plants were screened and visualized on Biovia Discovery-Studio. Moreover, SARS-CoV-2 E protein's secondary structural insights were deciphered using Swiss Model and ProFunc web server. Results: Glycyrrhizic acid, triterpene glycoside isolated from plants of Glycyrrhiza (licorice) showed interactions with envelope protein at chain A: Arg 61, chain B: Phe 23, chain B: Tyr 57, and chain C: Val 25. ß- boswellic acid, an ayurvedic herb (pentacyclic terpenoid are produced by Boswellia) represented direct interactions and indirect binding with chain C. Their pharmacological aspects and drug-likeness properties were deduced by DruLiTo. Toxicological assessment, along with their ADME profiling, was validated using vNNADMET. The findings showed that ligands, ß-boswellic acid, and glycyrrhizic acid possessed the best bindings, with the target having binding affinity (-9.1 kcal/mol) amongst compounds tested against SARS-CoV-2 E. In-vitro studies reveals the promising effect as potent SARS-CoV-2 E inhibitors. Functionality loss and structural disruptions with ∼90% were observed by UV-spectra and fluorescent based analyses. Conclusion: The study demonstrated that ß-boswellic acid, and glycyrrhizic acid are strong SARS-CoV-2 E protein inhibitors. In addition, the work linked GA antiviral activity to its effect on SARS-CoV- 2 E protein that can pave the way for designing antiviral therapeutics.

5.
J Food Sci Technol ; 59(1): 86-94, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35068554

RESUMO

Deep frying of food is a common practice that leads to the formation of lipid oxidation products. These lipid oxidation products have a role in the Maillard reaction, which ultimately leads to the formation of cancer-causing and neurotoxic substance acrylamide. In this regard, the Psidium guajava leaves extract-treated sunflower oil on oxidative stability and acrylamide content in pooris a popular deep-fried staple food in India were studied and compared with synthetic antioxidant butylated hydroxytoluene (BHT) till four frying cycles. P. guajava leaves contain 173.33 ± 1.95 mg GAE/g extract total phenolic content and 20.43 ± 0.25 mg RUE/g extract total flavonoid content. Some of the phytochemicals in the extract were identified and quantified by HPTLC. P. guajava leaves extract (1 g) contained 0.039 mg gallic acid, 0.196 mg rutin, 0.021 mg naringenin, 0.059 mg ferulic acid. The IC50 values for guava leaves extract, BHT, and ascorbic acid were 61.4, 30.4, 26.6 µg/mL, respectively. The peroxide and p-anisidine values indicated that P. guajava leaves extract inhibited lipid oxidation and provided oxidative stability. Pooris fried in P. guajava leaves extract-treated, BHT treated sunflower oil contained a lower acrylamide than pooris fried in control sunflower oil. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s13197-021-04984-y).

6.
J Control Release ; 341: 555-565, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34906604

RESUMO

Antibody drug conjugates (ADCs) are an emerging therapeutic modality for targeted cancer treatment. They represent the unique amalgamation of chemotherapy and immunotherapy. ADCs comprise of monoclonal antibodies linked with drugs (payloads) through a chemical linker designed to deliver the cytotoxic moiety to the cancer cells. The present paper is a review of recent clinical advances of each component of ADCs (antibody/linker/payload) and how the individual component influences the activity of ADCs. The review discusses opportunities for improving ADCs efficiency and ways to have a better antibody-based molecular platform, which could substantially increase chemotherapy outcomes. This review casts an outlook on how ADCs enhancement in terms of their pharmacokinetics, therapeutic indexes and safety profiles can overcome the prevailing challenges like drug resistance in cancer treatment. A novel strategy of augmenting antibodies with nanoparticles anticipates a huge success in terms of targeted delivery of drugs in several diseases. Antibody conjugated nanoparticles (ACNPs) are a very promising strategy for the cutting-edge development of chemo/immunotherapies for efficient delivery of payloads at the targeted cancer cells. The avenues of a high drug to antibody ratio (DAR) owing to the selection of broad chemotherapy payloads, regulating drug release eliciting higher avidity of ACNPs over ADCs will be the modern immunotherapeutics. ACNPs carry immense potential to mark a paradigm shift in cancer chemotherapy that may be a substitute for ADCs.


Assuntos
Antineoplásicos Imunológicos , Antineoplásicos , Imunoconjugados , Nanopartículas , Anticorpos Monoclonais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Antineoplásicos Imunológicos/farmacocinética
7.
J Food Sci ; 86(12): 5159-5174, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34812504

RESUMO

Trans fats are desired by the edible oil industry as they impart firmness, plasticity, and oxidative stability to oil. However, clinical trials have demonstrated the adverse effects of trans fats in food on human health and nutrition. Regulatory actions have been taken up by government and non-government bodies worldwide to eliminate the presence of trans fats in the food supply. The World Health Organization (WHO) has launched a "REPLACE" action plan to eliminate trans-fat from the global food industry by 2023. A few enabling technologies are developed to mitigate trans fats namely, trait-enhanced oils, modification in the hydrogenation process, interesterification, fractionation, blending, and oleogelation. Some of them have the drawback of replacing trans-fat with saturated fats. Interesterification and oleogelation are in-trend techniques with excellent potential in replacing trans fats without compromising the desired functionality and nutritional quality attributes. This review presents an overview of trans fatty acid for example, its dietary intake in food products, possible adverse health impact, regulations, and approaches to reduce the usage of trans fats for food application. PRACTICAL APPLICATION: The requirement for the replacement of trans fatty acids (TFAs) in food supply globally has challenged the food industry to find a novel substitute for trans fats without compromising the desired functionality and nutritional property. This review presents detailed background on trans fats, their health impacts and current trends of reformulation of oils and fats to mitigate their presence in food supply chains. Information compiled in this paper will help food scientists and technologists, chemists, food processors, and retailers as there is an urgent need to find novel technologies and substitutes to replace trans fats in processed foods.


Assuntos
Ácidos Graxos trans , Ingestão de Alimentos , Ácidos Graxos , Abastecimento de Alimentos , Humanos , Hidrogenação , Ácidos Graxos trans/efeitos adversos
8.
Nanomaterials (Basel) ; 11(10)2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34685051

RESUMO

Rapid and simple electroanalysis of acrylamide (ACR) was feasible by a gold electrode modified with gold nanoparticles (AuNPs) and dithiothreitol (DTT) with enhanced detection sensitivity and selectivity. The roughness of bare gold (Au) increased from 0.03 µm to 0.04 µm when it was decorated with AuNPs. The self-assembly between DTT and AuNPs resulted in a surface roughness of 0.09 µm. The DTT oxidation occurred at +0.92 V. The Au/AuNPs/DTT surface exhibited a surface roughness of 0.24 µm after its exposure to ACR with repeated analysis. SEM imaging illustrated the formation of a polymer layer on the Au/AuNPs/DTT surface. Surface plasmon resonance analysis confirmed the presence of AuNPs and DTT on the gold electrode and the binding of ACR to the electrode's active surface area. The peak area obtained by differential pulse voltammetry was inversely proportional to the ACR concentrations. The limit of detection (LOD) and the limit of quantitation (LOQ) were estimated to be 3.11 × 10-9 M and 1 × 10-8 M, respectively, with wide linearity ranging from 1 × 10-8 M to 1 × 10-3 M. The estimated levels of ACR in potato chips and coffee samples by the sensor were in agreement with those of high-performance liquid chromatography.

9.
Bioresour Technol ; 340: 125627, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34330004

RESUMO

Transglutaminase forms isopeptide bonds in proteins which are helpful in various industrial applications. However, low productivity and high cost are the major bottlenecks for industrial Transglutaminase production. The present study describes the regulatory mechanism of microbial Transglutaminase (MTGase) biosynthesis from Streptomyces mobaraensis and the effect of key regulators to maximize production. The transcriptional responses under the effect of various key modulators of MTGasebiosynthesis were evaluated. Productivity of MTGase with novel biosynthesis approach by regulators augmentation was correlated by transcriptional profiling. The optimization by key modulators by combinational supplementation led to 2-fold rise in activity. The functional attributes, the copy number of MTGase gene and relative changes were assessed by Real-Time quantitative PCR. Protease, MgCl2, CTAB induced upregulation, whereas PMSF, NaF and bleomycin sulphate showed inhibitory action on MTGase production and activity. The optimization by combinational supplementation of key modulators led to 4.27-fold increase (6.11 IU/mL) in production.


Assuntos
Streptomyces , Transglutaminases , Endopeptidases , Proteínas , Streptomyces/genética , Transglutaminases/genética
10.
Biotechnol Rep (Amst) ; 30: e00613, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33996521

RESUMO

Antimicrobial resistance (AMR) is one of the serious global public health threats that require immediate action. With the emergence of new resistance mechanisms in infection-causing microorganisms such as bacteria, fungi, and viruses, AMR threatens the effective prevention and treatment of diseases caused by them. This has resulted in prolonged illness, disability, and death. It has been predicted that AMR will lead to over ten million deaths by 2050. The rapid spread of multidrug-resistant bacteria is also causing old antibiotics to become ineffective. Among the diverse factors contributing to AMR, intrinsic biofilm development has been highlighted as an essential contributing facet. Moreover, biofilm-derived antibiotic tolerance leads to serious recurrent chronic infections. Therefore, the discovery of novel bioactive molecules is a potential solution that can help combat AMR. To achieve this, sustained mining of novel antimicrobial leads from actinobacteria, particularly marine actinobacteria, can be a promising strategy. Given their vast diversity and different habitats, the extraordinary capacity of actinobacteria can be tapped to synthesize new antibiotics or bioactive molecules for biofilm inhibition. Advanced screening strategies and novel approaches in the field of modern biochemical and molecular biology can be used to detect such new compounds. In view of this, the present review focuses on understanding some of the recent strategies to inhibit biofilm formation and explores the potential role of marine actinobacteria as sources of novel antibiotics and biofilm inhibitor molecules.

11.
RSC Adv ; 11(55): 34613-34630, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-35494746

RESUMO

Breast cancer is the most common malignancy among women. With the aim of decreasing the toxicity of conventional breast cancer treatments, an alternative that could provide appropriate and effective drug utilization was envisioned. Thus, we contemplated and compared the in vitro effects of microbial transglutaminase nanoflowers (MTGase NFs) on breast cancer cells (MCF-7). Transglutaminase is an important regulatory enzyme acting as a site-specific cross-linker for proteins. With the versatility of MTGase facilitating the nanoflower formation by acting as molecular glue, it was demonstrated to have anti-cancer properties. The rational drug design based on a transglutaminase enzyme-assisted approach led to the uniform shape of petals in these nanoflowers, which had the capacity to act directly as an anti-cancer drug. Herein, we report the anti-cancer characteristics portrayed by enzymatic MTGase NFs, which are biocompatible in nature. This study demonstrated the prognostic and therapeutic significance of MTGase NFs as a nano-drug in breast cancer treatment. The results on MCF-7 cells showed a significantly improved in vitro therapeutic efficacy. MTGase NFs were able to exhibit inhibitory effects on cell viability (IC50-8.23 µg ml-1) within 24 h of dosage. To further substantiate its superior anti-proliferative role, the clonogenic potential was measured to be 62.8%, along with migratory inhibition of cells (3.76-fold change). Drastic perturbations were induced (4.61-fold increase in G0/G1 phase arrest), pointed towards apoptotic induction with a 58.9% effect. These results validated the role of MTGase NFs possessing a cytotoxic nature in mitigating breast cancer. Thus, MTGase bestows distinct functionality towards therapeutic nano-modality, i.e., nanoflowers, which shows promise in cancer treatment.

12.
Bioresour Technol ; 323: 124563, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33360946

RESUMO

Production of platform chemicals has been advocated as a sustainable option to tackle the problems associated with agro-waste management. In this report, for the first time, efforts were made to effectively produce second-generation lactic acid from rice straw pretreated with imidazolium ionic liquid [EMIM][OAc] and subsequently fermented with a promising Lactobacillus plantarum SKL-22 strain saccharified with a commercial cellulase enzyme. Medium optimization was carried out to enhance the lactic acid (LA) yield by response surface methodology. In a 5 L bioreactor, the process was further upscale, and a yield increment of 1.11% was observed. The process using rice straw as substrate led to a LA yield of 36.75 g/L from L. plantarum SKL-22 in a single pot bioprocess. Overall, the above finding has shown the ability of L. plantarum SKL-22 to produce LA from the hydrolysate of rice straw. This study presented a novel environmental-friendly method for LA production.


Assuntos
Celulase , Líquidos Iônicos , Lactobacillus plantarum , Oryza , Celulase/metabolismo , Fermentação , Ácido Láctico , Lactobacillus plantarum/metabolismo , Oryza/metabolismo
13.
J Basic Microbiol ; 61(1): 4-14, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32896907

RESUMO

Implementing two-way strategies to enhance the lipid production in Rhodotorula mucilaginosa with the help of metabolic engineering was focused on the overexpression of acetyl coenzyme A carboxylase (ACC1 carboxylase) gene and repression of 3-hydroxy 3-methylglutaryl reductase (HMG-CoA reductase). Using an inducer (sodium citrate) and inhibitor (rosuvastatin), the amounts of biomass, lipid, and carotenoid were estimated. In the presence of inhibitor (200 mM), 62% higher lipid concentration was observed, while 44% enhancement was recorded when inducer (3 mM) was used. A combination of both inhibitor and inducer resulted in a 57% increase in lipid concentration by the oleaginous yeast. These results were again confirmed by real-time polymerase chain reaction by targeting the expression of the genes coding for ACC1 carboxylase and 13-fold increase was recorded in the presence of inducer as compared with control. This combined strategy (inducer and inhibitor use) has been reported for the first time as far as the best of our knowledge. The metabolic engineering strategies reported here will be a powerful approach for the enhanced commercial production of lipids.


Assuntos
Acetil-CoA Carboxilase/genética , Ácidos Graxos/metabolismo , Hidroximetilglutaril-CoA Redutases/genética , Rhodotorula/metabolismo , Biomassa , Carotenoides/metabolismo , Expressão Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Engenharia Metabólica , Rhodotorula/efeitos dos fármacos , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento , Rosuvastatina Cálcica/farmacologia , Citrato de Sódio/farmacologia
14.
Int J Biol Macromol ; 163: 1747-1758, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32961179

RESUMO

The chemical cross-linkers are difficult to be removed from the scaffold materials, which limit their application in tissue engineering; designing an efficient biocompatible hydrogel is though challenging is desirable. The aim of the present study was to immobilize microbial Transglutaminase (MTGase) enzyme on multi-walled carbon nanotubes (MWCNTs) for its application in hydrogel scaffolds designing. MTGase from Streptomyces mobaraensis, a non-toxic biological cross-linker, was employed for a greener approach with enhanced biochemical and structural properties. The maximum immobilization efficiency of 58% was achieved when MTGase was covalently coupled on MWCNTs. The kinetic studies showed 4.76-fold increase in catalytic efficiency and good reusability upto seven cycles. Attachment of enzyme on MWCNTs surface was studied through SEM and FTIR. The immobilized enzyme showed good cross-linking efficiency in gelatin hydrogel scaffold resulting decrease in swelling ratio of hydrogel. Our findings report for the first time the development of novel biocompatible hydrogel scaffolds with immobilized MTGase onto MWCNTS. Inevitable damage of hydrogels are incurred during their applications. To offset the damage of hydrogels, the creation of bioinspired hydrogels emulating native tissue microenvironment is highly significant. Microbial TGase holds promising future with its applicability as a cross-linker of hydrogel scaffolds in the area of tissue engineering.


Assuntos
Enzimas Imobilizadas/química , Hidrogéis/química , Nanotubos de Carbono/química , Alicerces Teciduais/química , Transglutaminases/química , Materiais Biocompatíveis/química , Materiais Biomiméticos/química , Gelatina/química , Cinética , Streptomyces/química , Engenharia Tecidual/métodos
15.
3 Biotech ; 9(6): 240, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31168433

RESUMO

Sporotrichum thermophile, a known producer of industrial enzymes exhibited stability in the presence of ionic liquids (ILs).The study reports, for the first time, the stress response of S. thermophile upon exposure to ILs. In vitro assay showed increased anti-oxidative enzyme levels indicating ROS-mediated oxidative stress by ILs. The proteomic profile and identification of differential proteins confirmed the fungal adaptations by (i) increased expression of glycolytic enzymes and ATP synthases (ii) downregulation of TCA cycle and protein synthesis machinery components (iii) expression of HSP70 and catalase/peroxidase. These changes are indicative of metabolic regulation of many important pathways and how ILs can be used to manipulate protein behavior.

16.
Bioresour Technol ; 287: 121391, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31076295

RESUMO

This work studied the production of Transglutaminase (TGase) using wheat bran as carbon source. The medium components and culture conditions were optimized by statistical Box-Behnken response surface methodology. The release of active Transglutaminase was enhanced by adding (i) protease to remove pro-region to make inactive enzyme to active form, (ii) Cetyl trimethyl ammonium bromide (CTAB) which facilitated more secretion. Under finally optimized conditions viz. 5 g wheat bran, protease: 39.14 U, magnesium chloride (MgCl2): 0.10 M, CTAB: 0.08% and inoculation size: 2% led to 4-fold (12.949 ±â€¯0.061 IU/g) increased TGase production over that of un-optimized conditions. The application of TGase was shown to be useful in effective casein cross-linking.


Assuntos
Streptomyces , Endopeptidases , Fermentação , Resíduos Industriais , Cloreto de Magnésio , Transglutaminases
17.
Bioresour Technol ; 288: 121494, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31128540

RESUMO

Statistical optimization using industrial rice-straw hydrolysate (C6 stream) containing 5.0% total sugars was carried out for enhancing the rhamnolipid production from Achromobacter sp. (PS1) with subsequent adoption of a sequential fermentation approach with fill-and-draw operation for further increment. The interactive effects of six influential variables obtained from one-factor-at-a-time approach as sodium nitrate, yeast extract, ferrous sulphate, phosphate concentrations and agitation in presence of lignocellulosic hydrolyzed sugars as a basal medium using central composite design revealed the experimental rhamnolipid yield of 5.46 g/L at optimum conditions of total sugars 40 g/L (w/v), sodium nitrate 6.0 (g/L), yeast extract 2 (g/L), ferrous sulphate 0.2 (mg/L) and phosphate 1000 mM at 100 rpm at 30 °C in 8 days. The sequential approach further resulted in an overall yield of 19.35 g/L of rhamnolpid in five sequential-cycles with an increase of 258% over the batch process on account of nutrients replenishment and dilution of toxic by-products.


Assuntos
Achromobacter , Fermentação , Glicolipídeos , Lignina , Rios
18.
Bioprocess Biosyst Eng ; 42(8): 1301-1315, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31028463

RESUMO

With the ever growing increase in the demands of biosurfactants, the present study was focused in developing a set of parameters influencing biosurfactant production using one-factor-at-a-time (OFAT) approach in chemically defined medium from an indigenous isolate of Achromobacter sp. (PS1). Subsequently, the feasibility of biosurfactant production was examined using influential OFAT parameters in same medium, replacing only carbon source with lignocellulosic hydrolyzed sugars. These sugars were obtained from ammonia (15% v/v) soaking pretreatment of lignocellulosic residues (7.5% solid loading at 70 °C for 72 h) with subsequent saccharification using lignocellulolytic enzymes. OFAT influential parameters observed were dextrose (3-4% w/v); C/N ratio 8.3 using sodium nitrate and beef extract; 2 × 10-5 grams equivalents Fe2+; 1500 mM PO43- in minimal salt medium (MSM) at pH 7.0, 120 rpm, 30 °C resulting in 4.13 ± 0.12 g/L rhamnolipid in 192 h with 30.42 mN/m surface tension and 136 mg/L critical micelle concentration (CMC). Biosurfactant was characterized using tandem-MS and NMR as rhamnolipid with six-congeners, Rha-C10-C10 and Rha-Rha-C10-C10 being the most abundant. Rhamnolipid showed broad range stability at temperatures (30-121 °C), pH (6-12), and salinity (0.5-5% w/v) of NaCl. In Rice-straw (RS) hydrolysate, maximum glucan (73.10%) and xylan (91.13%) were obtained and the RS-hydrolysate medium with a total of 4.55% (w/v) sugars under optimum OFAT parameters (other than dextrose) showed at par production of 3.55 ± 0.06 g/L of rhamnolipid in 192 h with YBS/S (biosurfactant yield per gram of sugar consumed) of 0.08 g/g and YBS/CDW (biosurfactant yield per gram of cell biomass) of 0.68 g/g.


Assuntos
Achromobacter/crescimento & desenvolvimento , Amônia/química , Glicolipídeos/biossíntese , Lignina/química , Tensoativos/metabolismo
19.
Bioresour Technol ; 278: 372-382, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30709766

RESUMO

In today's scenario of global climate change, there is a colossal demand for sustainable industrial processes and enzymes from thermophiles. Plausibly, thermozymes are an important toolkit, as they are known to be polyextremophilic in nature. Small genome size and diverse molecular conformational modifications have been implicated in devising adaptive strategies. Besides, the utilization of chemical technology and gene editing attributions according to mechanical necessities are the additional key factor for efficacious bioprocess development. Microbial thermozymes have been extensively used in waste management, biofuel, food, paper, detergent, medicinal and pharmaceutical industries. To understand the strength of enzymes at higher temperatures different models utilize X-ray structures of thermostable proteins, machine learning calculations, neural networks, but unified adaptive measures are yet to be totally comprehended. The present review provides a recent updates on thermozymes and various interdisciplinary applications including the aspects of thermophiles bioengineering utilizing synthetic biology and gene editing tools.


Assuntos
Biotecnologia , Biocombustíveis , Edição de Genes , Temperatura Alta
20.
Int J Biol Macromol ; 122: 962-968, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30408454

RESUMO

An ascorbate peroxidase from a new source Musa paradisiaca leaf juice has been purified to homogeneity using a simple procedure involving concentration by ultra filtration and anion exchange chromatography on diethyl amino ethyl [DEAE] cellulose column. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis [SDS-PAGE] analysis of the purified enzyme has shown a single protein band of molecular mass 208.9 kDa which has been confirmed by native-PAGE and intact mass analysis by mass spectrometry. The Km and kcat values of the enzyme using ascorbate and H2O2 as the variable substrates were 0.13 m mol L-1, 40.42 s-1 and 0.23 m mol L-1, 27.24 s-1, respectively. The pH and temperature optima of the enzyme were 7.0 and 298 K, respectively. The enzyme transformed approximately 97% methyl phenyl sulfide to its sulfoxide. The product was racemic mixture.


Assuntos
Ascorbato Peroxidases/metabolismo , Musa/enzimologia , Safrol/análogos & derivados , Sulfetos/metabolismo , Sequência de Aminoácidos , Ascorbato Peroxidases/química , Biotransformação , Concentração de Íons de Hidrogênio , Folhas de Planta/enzimologia , Safrol/metabolismo , Temperatura
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