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1.
World J Microbiol Biotechnol ; 35(9): 131, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432251

RESUMO

Cholesterol is a C27-sterol employed as starting material for the synthesis of valuable pharmaceutical steroids and precursors. The microbial transformations of cholesterol have been widely studied, since they are performed with high regio- and stereoselectivity and allow the production of steroidal compounds which are difficult to synthesize by classical chemical methods. In recent years, ongoing research is being conducted to discover novel biocatalysts and to develop biotechnological processes to improve existing biocatalysts and biotransformation reactions. The main objective of this review is to present the most remarkable advances in fungal and bacterial transformation of cholesterol, focusing on the different types of microbial reactions and biocatalysts, biotransformation products, and practical aspects related to sterol dispersion improvement, covering literature since 2000. It reviews the conversion of cholesterol by whole-cell biocatalysts and by purified enzymes that lead to various structural modifications, including side chain cleavage, hydroxylation, dehydrogenation/reduction, isomerization and esterification. Finally, approaches used to improve the poor solubility of cholesterol in aqueous media, such as the use of different sterol-solubilizing agents or two-phase conversion system, are also discussed.


Assuntos
Bactérias/metabolismo , Biotecnologia/métodos , Colesterol/metabolismo , Fungos/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Biotecnologia/tendências , Biotransformação , Enzimas/metabolismo , Fungos/genética , Fungos/crescimento & desenvolvimento
2.
Cell Mol Biol Lett ; 24: 40, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31223315

RESUMO

Paclitaxel is a well-known anticancer agent with a unique mechanism of action. It is considered to be one of the most successful natural anticancer drugs available. This study summarizes the recent advances in our understanding of the sources, the anticancer mechanism, and the biosynthetic pathway of paclitaxel. With the advancement of biotechnology, improvements in endophytic fungal strains, and the use of recombination techniques and microbial fermentation engineering, the yield of extracted paclitaxel has increased significantly. Recently, paclitaxel has been found to play a large role in tumor immunity, and it has a great potential for use in many cancer treatments.


Assuntos
Biotecnologia/métodos , Imunoterapia , Neoplasias/terapia , Paclitaxel/uso terapêutico , Animais , Antineoplásicos Fitogênicos/biossíntese , Antineoplásicos Fitogênicos/uso terapêutico , Fermentação , Fungos/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Paclitaxel/biossíntese , Paclitaxel/farmacologia
3.
Nat Commun ; 10(1): 2641, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201325

RESUMO

Epsilon toxin (Etx), a potent pore forming toxin (PFT) produced by Clostridium perfringens, is responsible for the pathogenesis of enterotoxaemia of ruminants and has been suggested to play a role in multiple sclerosis in humans. Etx is a member of the aerolysin family of ß-PFTs (aß-PFTs). While the Etx soluble monomer structure was solved in 2004, Etx pore structure has remained elusive due to the difficulty of isolating the pore complex. Here we show the cryo-electron microscopy structure of Etx pore assembled on the membrane of susceptible cells. The pore structure explains important mutant phenotypes and suggests that the double ß-barrel, a common feature of the aß-PFTs, may be an important structural element in driving efficient pore formation. These insights provide the framework for the development of novel therapeutics to prevent human and animal infections, and are relevant for nano-biotechnology applications.


Assuntos
Toxinas Bacterianas/química , Clostridium perfringens/ultraestrutura , Animais , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/metabolismo , Biotecnologia/métodos , Linhagem Celular , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle , Clostridium perfringens/genética , Clostridium perfringens/metabolismo , Clostridium perfringens/patogenicidade , Microscopia Crioeletrônica , Cães , Enterotoxemia/microbiologia , Enterotoxemia/prevenção & controle , Modelos Moleculares , Mutagênese Sítio-Dirigida , Nanotecnologia/métodos , Conformação Proteica em Folha beta/genética , Multimerização Proteica/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
4.
Nat Nanotechnol ; 14(6): 541-553, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31168083

RESUMO

Nanobiotechnology has the potential to enable smart plant sensors that communicate with and actuate electronic devices for improving plant productivity, optimize and automate water and agrochemical allocation, and enable high-throughput plant chemical phenotyping. Reducing crop loss due to environmental and pathogen-related stresses, improving resource use efficiency and selecting optimal plant traits are major challenges in plant agriculture industries worldwide. New technologies are required to accurately monitor, in real time and with high spatial and temporal resolution, plant physiological and developmental responses to their microenvironment. Nanomaterials are allowing the translation of plant chemical signals into digital information that can be monitored by standoff electronic devices. Herein, we discuss the design and interfacing of smart nanobiotechnology-based sensors that report plant signalling molecules associated with health status to agricultural and phenotyping devices via optical, wireless or electrical signals. We describe how nanomaterial-mediated delivery of genetically encoded sensors can act as tools for research and development of smart plant sensors. We assess performance parameters of smart nanobiotechnology-based sensors in plants (for example, resolution, sensitivity, accuracy and durability) including in vivo optical nanosensors and wearable nanoelectronic sensors. To conclude, we present an integrated and prospective vision on how nanotechnology could enable smart plant sensors that communicate with and actuate electronic devices for monitoring and optimizing individual plant productivity and resource use.


Assuntos
Técnicas Biossensoriais/métodos , Biotecnologia/métodos , Produção Agrícola/métodos , Produtos Agrícolas , Nanotecnologia/métodos , Plantas Geneticamente Modificadas , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Humanos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento
5.
Enzyme Microb Technol ; 127: 1-5, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31088611

RESUMO

A two-step strategy was employed to culture Dunaliella tertiolecta, an oleaginous unicellular green alga, combined by the salt stress and sodium azide intervention, to observe their effects on its lipid accumulation. When the algae cultured at different salt concentrations reached the logarithmic growth phase, sodium azide was added. The results showed that the addition of sodium azide significantly increased the lipid content and had no significant effect on cell biomass. The lipid yield and single cell lipid content under 50 µM sodium azide increased by 10.4% and 21.7%. Under the two-step culture condition, combining of the treatment of 50 µM sodium azide and 2.5 M salt stress, the total lipid productivity and single-cell lipid content were 10% and 70.5% higher than that of the control. It seemed that sodium azide and salinity might have a synergistic effect on the lipid accumulation of D. tertiolecta. It can be concluded that sodium azide is an effective inducer of lipid accumulation in D. tertiolecta, and two-stage cultivation is a feasible way to improve lipid accumulation in microalgae.


Assuntos
Clorofíceas/efeitos dos fármacos , Clorofíceas/metabolismo , Inibidores Enzimáticos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Estresse Salino , Azida Sódica/metabolismo , Biotecnologia/métodos , Clorofíceas/crescimento & desenvolvimento , Lipídeos/análise
6.
Environ Sci Pollut Res Int ; 26(18): 18520-18532, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31049862

RESUMO

The present work investigated the potential of the green alga Chlorella vulgaris to produce high-quality biofuel under culture stress conditions. The cultivation was carried out in a 1000 l open plate tank system, which provides biomass yields comparable to open pond systems, but with less area needed. Algal biomass and lipid content were measured repeatedly. We compared the two solvent systems n-hexane and hexane/isopropanol (HIP) for extraction efficiency of lipids and applied three different extraction methods Soxhlet, soaking, and soaking followed by Soxhlet (soak-Sox). The combination of the HIP solvent and the soak-Sox provided the highest lipid yield (15.8 ± 0.174). Volumetric biomass and lipid productivity were 0.201 g l-1 day-1 and 31.71 mg l-1 day-1, respectively, whereas areal biomass and lipid productivity were 25.73 g m-2 day-1 and 4.066 g m-2 day-1, respectively. The fatty acid profile by means of gas chromatography resulted in seven fatty acids from C12 to C18. The most abundant fatty acid methyl esters (FAMES) were palmitic (C16:0), oleic (C18:1), and stearic (C18:0) acids. Lipid synthesis enhanced by optimizing the Kuhl growth medium with replacing nitrate by urea (50% N compared to the original recipe) increased salt content (10 g/l NaCl), ferrous sulfate (0.5 g/l), and sodium acetate addition (1 g/l). With regard to density, kinematic viscosity, gravity, pour point, flash point, and cetane number, the Chlorella-biodiesel comply with ASTM and EN standards thus pointing at the high potential of lipids synthesized by Chlorella as a feedstock for biodiesel production.


Assuntos
Biocombustíveis/análise , Biotecnologia/métodos , Chlorella vulgaris/crescimento & desenvolvimento , Ácidos Graxos/análise , Microalgas/crescimento & desenvolvimento , Biomassa , Biotecnologia/instrumentação , Chlorella vulgaris/metabolismo , Meios de Cultura/química , Microalgas/metabolismo
7.
Prep Biochem Biotechnol ; 49(8): 744-758, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31050587

RESUMO

Lignocellulosic biomass (LB) is the renewable feedstock for the production of fuel/energy, feed/food, chemicals, and materials. LB could also be the versatile source of the functional oligosaccharides, which are non-digestible food ingredients having numerous applications in food, cosmetics, pharmaceutical industries, and others. The burgeoning functional food demand is expected to be more than US$440 billion in 2022. Because of higher stability at low pH and high temperature, oligosaccharides stimulate the growth of prebiotic bifidobacteria and lactic acid bacteria. Xylooligosaccharides (XOS) are major constituents of oligosaccharides consisting of 2-7 xylose monomeric units linked via ß-(1,4)-linkages. XOS can be obtained from various agro-residues by thermochemical pretreatment, enzymatic or chemoenzymatic methods. While thermochemical methods are fast, reproducible, enzymatic methods are substrate specific, costly, and produce minimum side products. Enzymatic methods are preferred for the production of food grade and pharmaceutically important oligosaccharides. XOS are potent prebiotics having antioxidant properties and enhance the bio-adsorption of calcium and improving bowel functions, etc. LB can cater to the increasing demand of oligosaccharides because of their foreseeable amount and the advancements in technology to recover oligosaccharides. This paper summarizes the methods for oligosaccharides production from LB, classification, and benefits of oligosaccharides on human health.


Assuntos
Biotecnologia/métodos , Glucuronatos/metabolismo , Lignina/metabolismo , Oligossacarídeos/metabolismo , Biomassa , Fibras na Dieta/análise , Humanos , Plantas/enzimologia , Plantas/metabolismo , Xilosidases/metabolismo
8.
Molecules ; 24(9)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086077

RESUMO

It is well known that terrestrial environments host an immense microbial biodiversity. Exposed to different types of stress, such as UV radiation, temperature fluctuations, water availability and the inter- / intra-specific competition for resources, terrestrial microorganisms have been evolved to produce a large spectrum of bioactive molecules. Bacteria, archaea, protists, fungi and algae have shown a high potential of producing biomolecules for pharmaceutical or other industrial purposes as they combine a sustainable, relatively low-cost and fast-production process. Herein, we provide an overview of the different bioactive molecules produced by terrestrial microorganisms with skin protecting applications. The high content in polyphenolic and carotenoid compounds produced by several strains, as well as the presence of exopolysaccharides, melanins, indole and pyrrole derivatives, mycosporines, carboxylic acids and other molecules, are discussed in the context of their antioxidant, photo-protective and skin-whitening activity. Relevant biotechnological tools developed for the enhanced production of high added value natural products, as well as the protecting effect of some antioxidant, hydrolytic and degrading enzymes are also discussed. Furthermore, we describe classes of microbial compounds that are used or have the potential to be used as antimicrobials, moisturizers, biosurfactants, pigments, flavorings and fragrances.


Assuntos
Produtos Biológicos/análise , Biotecnologia/métodos , Cosméticos/análise , Antioxidantes/análise , Archaea/metabolismo , Bactérias/metabolismo , Cosméticos/metabolismo , Fungos/metabolismo
9.
Nat Commun ; 10(1): 2013, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043592

RESUMO

Tight control over protein degradation is a fundamental requirement for cells to respond rapidly to various stimuli and adapt to a fluctuating environment. Here we develop a versatile, easy-to-handle library of destabilizing tags (degrons) for the precise regulation of protein expression profiles in mammalian cells by modulating target protein half-lives in a predictable manner. Using the well-established tetracycline gene-regulation system as a model, we show that the dynamics of protein expression can be tuned by fusing appropriate degron tags to gene regulators. Next, we apply this degron library to tune a synthetic pulse-generating circuit in mammalian cells. With this toolbox we establish a set of pulse generators with tailored pulse lengths and magnitudes of protein expression. This methodology will prove useful in the functional roles of essential proteins, fine-tuning of gene-expression systems, and enabling a higher complexity in the design of synthetic biological systems in mammalian cells.


Assuntos
Sequência de Aminoácidos/genética , Regulação da Expressão Gênica , Engenharia de Proteínas/métodos , Proteólise , Biotecnologia/métodos , Células HEK293 , Meia-Vida , Células HeLa , Humanos , Microscopia Intravital/métodos , Células-Tronco Mesenquimais , Microscopia de Fluorescência , Biologia Sintética/métodos
10.
J Agric Food Chem ; 67(22): 6248-6256, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31090409

RESUMO

A lignin amphoteric surfactant and betaine could enhance the enzymatic hydrolysis of lignocellulose and recover cellulase. The effects of lignosulfonate quaternary ammonium salt (SLQA) and dodecyl dimethyl betaine (BS12) on enzymatic hydrolysis digestibility, ethanol yield, yeast cell viability, and other properties of high-solid enzymatic hydrolysis and fermentation of a corncob residue were studied in this research. The results suggested that SLQA and 1 g/L BS12 effectively improved the ethanol yield through enhancing enzymatic hydrolysis. SLQA had no significant effect on the yeast cell membrane and glucose fermentation. However, 5 g/L BS12 reduced the ethanol yield as a result of the fact that 5 g/L BS12 damaged the yeast cell membrane and inhibited the conversion of glucose to ethanol. Our research also suggested that 1 g/L BS12 enhanced the ethanol yield of corncob residue fermentation, which was attributed to the fact that lignin in the corncob adsorbed BS12 and decreased its concentration in solution to a safe level for the yeast.


Assuntos
Biotecnologia/métodos , Celulose/metabolismo , Etanol/química , Etanol/metabolismo , Lignina/metabolismo , Resíduos/análise , Leveduras/metabolismo , Zea mays/microbiologia , Biocatálise , Biotecnologia/instrumentação , Celulase/química , Fermentação , Glucose/metabolismo , Hidrólise , Lignina/química , Tensoativos/química , Zea mays/metabolismo
11.
Nat Commun ; 10(1): 1734, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30988307

RESUMO

Peptide tags are a key resource, introducing minimal change while enabling a consistent process to purify diverse proteins. However, peptide tags often provide minimal benefit post-purification. We previously designed SpyTag, forming an irreversible bond with its protein partner SpyCatcher. SpyTag provides an easy route to anchor, bridge or multimerize proteins. Here we establish Spy&Go, enabling protein purification using SpyTag. Through rational engineering we generated SpyDock, which captures SpyTag-fusions and allows efficient elution. Spy&Go enabled sensitive purification of SpyTag-fusions from Escherichia coli, giving superior purity than His-tag/nickel-nitrilotriacetic acid. Spy&Go allowed purification of mammalian-expressed, N-terminal, C-terminal or internal SpyTag. As an oligomerization toolbox, we established a panel of SpyCatcher-linked coiled coils, so SpyTag-fusions can be dimerized, trimerized, tetramerized, pentamerized, hexamerized or heptamerized. Assembling oligomers for Death Receptor 5 stimulation, we probed multivalency effects on cancer cell death. Spy&Go, combined with simple oligomerization, should have broad application for exploring multivalency in signaling.


Assuntos
Biotecnologia/métodos , Proteínas/isolamento & purificação , Proteínas de Escherichia coli , Modelos Moleculares , Peptídeos/química , Proteínas Periplásmicas
12.
J Appl Microbiol ; 126(6): 1785-1796, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30953595

RESUMO

AIMS: This study reports the results of the application of a new agar-gauze biogel system activated with viable bacterial cells to altered wall paintings. METHODS AND RESULTS: Biocleaning using agar biogel and agar-gauze biogel systems was performed onsite by direct application to altered wall painting surfaces (25-1000 cm2 ). The treatments were performed for the restoration of two original Italian sites: (i) at the Vatican Museums, Cristo che salva Pietro dalle acque-La Navicella, a wall painting by Giovanni Lanfranco (1627-1628) and (ii) at Pisa Cathedral Cupola, Incarnato, a wall painting by Orazio Riminaldi (1593-1630) and his brother Girolamo Riminaldi. The novelty of this study is the use of viable Pseudomonas stutzeri A29 cells in an advanced agar-gauze biogel system and the short bio-application contact times of between 3 and 12 h. The historical artworks were altered by lipid and protein residues from past restoration, as confirmed by Py-gas chromatography-mass spectrometry and FT-IR data. The effectiveness of the biological treatment was assessed, and general considerations were discussed. CONCLUSIONS: The short bio-application contact time of advanced agar-gauze gel activated with viable P. stutzeri cells makes this biotechnology promising as an alternative method to the traditional onsite cleaning techniques currently in use for altered historical wall paintings. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, we report for the first time the biocleaning of altered materials located in vertical and vaulted areas using agar-gauze biogel with short application times. These findings are of great significance for future restoration activities and are crucial for determining the best preservation strategies in this field.


Assuntos
Biotecnologia/métodos , Poluentes Ambientais/metabolismo , Pinturas , Pseudomonas stutzeri/metabolismo , Ágar , Bandagens , Biodegradação Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Itália , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Molecules ; 24(7)2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934947

RESUMO

In this work, we explore the current knowledge about the phytochemistry and in vitro and in vivo evaluations of the extracts and, where appropriate, the main active components characterized and isolated from the Allamanda cathartica. Of the 15 Allamanda species, most phytochemical, pharmacological, and toxicological studies have focused on A. cathartica. These plants are used for the treatment of various health disorders. Numerous phytochemical investigations of plants from the A. cathartica have shown the presence of hydrocarbons, alcohols, esters, ethers, aldehydes, ketones, fatty acids, phospholipids, volatile compounds, phenolic compounds, flavonoids, alkaloids, steroids, terpenes, lactones, and carbohydrates. Various studies have confirmed that extracts and active substances isolated from the A. cathartica have multiple pharmacological activities. The species A. cathartica has emerged as a source of traditional medicine used for human health. Further studies on the phytochemical, pharmacological, and toxicological properties and their mechanisms of action, safety, and efficacy in the species of A. cathartica is recommended.


Assuntos
Apocynaceae/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Biotecnologia/métodos , Etnofarmacologia/métodos , Medicina Tradicional , Estrutura Molecular , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/toxicidade , Plantas Medicinais/química , Toxicologia/métodos
15.
Appl Microbiol Biotechnol ; 103(10): 3965-3978, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30941462

RESUMO

Azoreductases reductively cleave azo linkages by using NAD(P)H as an electron donor. The enzymes are widely found in bacteria and act on numerous azo dyes, which allow various unique applications. This review describes primary amino acid sequences, structures, substrates, physiological roles, and biotechnological applications of bacterial azoreductases to discuss their remarkable diversification. According to primary sequences, azoreductases were classified phylogenetically into four main clades. Most members of clades I-III are flavoproteins, whereas clade IV members include flavin-free azoreductases. Clades I and II prefer NADPH and NADH, respectively, as electron donors, whereas other members generally use both. Several enzymes formed no clades; moreover, some bacteria produce azoreductases with longer primary structures than those hitherto identified, which implies further diversification of bacterial azoreductases. The crystal structures commonly reveal the Rossmann folds; however, ternary structures are moderately varied with different quaternary conformation. Although physiological roles are obscure, several azoreductases have been shown to act on metabolites such as flavins, quinones, and metal ions more efficiently than on azo dyes. Considering that many homologs exclusively act on these metabolites, it is possible that azoreductases are actually side activities of versatile reductases that act on various substrates with different specificities. In parallel, this idea raises the possibility that homologous enzymes, even if these are already defined as other types of reductases, widely harbor azoreductase activities. Although azoreductases for which their genes have been identified are not abundant, it may be simple to identify azoreductases of biotechnological importance that have novel substrate specificities.


Assuntos
Compostos Azo/metabolismo , Bactérias/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Variação Genética , NADH NADPH Oxirredutases/genética , NADH NADPH Oxirredutases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , Biotecnologia/métodos , NADH NADPH Oxirredutases/química , NADH NADPH Oxirredutases/classificação , Conformação Proteica , Especificidade por Substrato
16.
IEEE Pulse ; 10(2): 3-7, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31021750

RESUMO

Could biotechnology stop aging? The answer may be yes, no, or something in between, depending on who is being asked and what it means to "stop" aging. For those at one end of the spectrum- life extension seekers (including some deep-pocketed Silicon Valley investors)-the answer is "yes." They believe biotechnology will lengthen human life spans to range anywhere from 1,000 years to forever. But for most, the answer is more nuanced and in- volves a dream of extended healthspan, rather than immortality. They imagine a future in which people over the age of 65 years are healthy, active, independent, and not burdened by disease, and that this is the norm rather than the exception. "Healthspanners" believe that one day, science will delay the onset of aging-related conditions and, as a side-effect, modestly extend life. Aging as we know it-and dread it-could become ancient history.


Assuntos
Biotecnologia/métodos , Biotecnologia/tendências , Longevidade , Humanos
17.
Lipids ; 54(4): 245-253, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30957876

RESUMO

Bacillus licheniformis I89 is a Gram-positive bacterium, a producer of the lantibiotic lichenicidin. No information is available on its fatty acid (FA) composition. Bacillus species are rich in branched FA (BrFA), claimed to be beneficial to human health and to treat diseases. Herein, the FA profile of B. licheniformis I89 was evaluated under different growth conditions: at two growth temperatures (37 and 50 °C) and at different growth phases (lag, exponential, and stationary), using gas chromatography-mass spectrometry. The FA profile revealed predominant BrFA of the iso-series and anteiso-series (i-15:0, ai-15:0, i-16:0, i-17:0, and ai-17:0) and low amounts of saturated FA (14:0, 16:0, and 18:0). Comparing the FA profiles at different temperatures, in the lag phase, at 50 °C, there was a decrease of ai-17:0 and a decrease of i-15:0 in the exponential phase, in comparison with 37 °C. In all growth phases, there was a decrease of ai-15:0 and an increase of i-17:0. From the lag to the stationary phase, at 50 °C, there was a decrease of ai-17:0 and i-16:0, whereas i-15:0 increased, while at 37 °C, there was an increase of i-15:0 and i-16:0, and a decrease in ai-15:0 and ai-17:0. B. licheniformis I89 can adapt its FA profile, at moderate temperatures, by changing the iso-FA and anteiso-FA composition and the iso/anteiso ratio. This nonpathogenic bacterium species can be used as a source of BrFA with putative beneficial health effects for gut protection and with reported antitumor properties, foreseeing its use for producing compounds with biotechnological applications.


Assuntos
Bacillus licheniformis/metabolismo , Biotecnologia/métodos , Ácidos Graxos/análise , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas
18.
Environ Sci Pollut Res Int ; 26(15): 14867-14882, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30968292

RESUMO

Fossil fuel resource is on the draining stage which leads to an increment in the cost of the petroleum products. Nowadays, research is focused on the development of environment-friendly lubricants which are derivatives of renewable sources. Bio-lubricants based on non-edible oil sources are environmentally friendly because they are non-hazardous and biodegradable and no emission of toxic gases were detected when they are used. This study involves the characterizations and advantages, as well as utilization of inedible plant oil-driven bio-lubricants as an alternative for tribological applications. This report also presents the status of the global lubricant market as well as the potential outlook of the bio-lubricants for their future usage. Non-edible plant oil-driven bio-lubricants bear high viscosity, high lubricity, and high viscosity index which can enhance the equipment service life and deserve the ability to carry the high load and results in a minimum amount of metal traces during combustion while applied to engines. Beside their advantages, some of the disadvantages are also there which can be addressed by the employment of certain additives available according to the applications. The detailed study about the different additives utilized during their use in the internal combustion engine is also described in detail during this study. This study provides a detailed description of the possibilities associated with bio-lubricant based on non-edible oil feedstocks to the automotive sector applications.


Assuntos
Biotecnologia/métodos , Lubrificantes , Óleos Vegetais/química , Biodegradação Ambiental , Corrosão , Lubrificantes/química , Lubrificantes/metabolismo , Metais , Veículos Automotores , Viscosidade
19.
Environ Sci Pollut Res Int ; 26(16): 16115-16124, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30972671

RESUMO

The present study reports the use of Citrus limetta (CL) residue for cultivating Chlorella sp. mixotrophically to augment production of biodiesel. The cultivation of Chlorella sp. using CL as media was carried out by employing a fed-batch technique in open tray (open tray+CL) and in software (BioXpert V2)-attached automated photobioreactor (PBR+CL) systems. Data showed the limit of nitrogen substituent and satisfactory organic source of carbon (OSC) in CL, causing > 2-fold higher lipid content in cells, cultivated in both the systems than in control. For the cells grown in both the systems, ≥ 3-fold enhancement in lipid productivity was observed than in control. The total fatty acid methyl ester (FAME) concentrations from lipids extracted from cells grew in PBR+CL and in open tray+CL techniques were calculated as 50.59% and 38.31%, respectively. The PBR+CL system showed improved outcomes for lipid content, lipid and biomass productivity, FAME characteristics and physical property parameters of biodiesel than those obtained from the open tray+CL system. The physical property parameters of biodiesel produced from algal cells grown in PBR+CL were comparable to existing fuel standards. The results have shown lower cold filter plugging point (- 6.57 °C), higher cetane number (58.04) and average oxidative stability (3.60 h). Collectively, this investigation unveils the novel deployment of CL as a cost-effective feedstock for commercialisation of biodiesel production.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Chlorella/crescimento & desenvolvimento , Citrus , Resíduos Industriais , Técnicas de Cultura Celular por Lotes , Biocombustíveis/análise , Biomassa , Biotecnologia/instrumentação , Carbono/metabolismo , Chlorella/metabolismo , Esterificação , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Metabolismo dos Lipídeos , Lipídeos/análise , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Nitrogênio/metabolismo , Fotobiorreatores
20.
Environ Sci Pollut Res Int ; 26(16): 16195-16209, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30972683

RESUMO

CO2, SO2, and NO are the main components of flue gas and can cause serious environmental issues. Utilization of these compounds in oleaginous microalgae cultivation not only could reduce air pollution but could also produce feedstock for biodiesel production. However, the continuous input of SO2 and NO inhibits microalgal growth. In this study, the toxicity of simulated flue gas (15% CO2, 0.03% SO2, and 0.03% NO, balanced with N2) was reduced through automatic pH feedback control. Integrated lipid production and CO2 fixation with the removal of SO2 and NO was achieved. Using this technique, a lipid content of 38.0% DW was achieved in Chlorella pyrenoidosa XQ-20044. The lipid composition and fatty acid profile indicated that lipid production by C. pyrenoidosa XQ-20044 cultured with flue gas is suitable as a biodiesel feedstock; 81.2% of the total lipids were neutral lipids and 99.5% of the total fatty acids were C16 and C18. The ratio of saturated fatty acids to monounsaturated fatty acids in the microalgal lipid content was 74.5%. In addition, CO2, SO2, and NO from the simulated flue gas were fixed and converted to biomass and lipids with a removal efficiency of 95.9%, 100%, and 84.2%, respectively. Furthermore, the utilization efficiencies of CO2, SO2, and NO were equal to or very close to their removal efficiencies. These results provide a novel strategy for combining biodiesel production with biofixation of flue gas.


Assuntos
Biotecnologia/métodos , Chlorella/efeitos dos fármacos , Chlorella/metabolismo , Lipídeos/biossíntese , Poluentes Atmosféricos/química , Poluentes Atmosféricos/isolamento & purificação , Poluentes Atmosféricos/toxicidade , Biocombustíveis , Biomassa , Biotecnologia/instrumentação , Dióxido de Carbono/isolamento & purificação , Dióxido de Carbono/toxicidade , Chlorella/crescimento & desenvolvimento , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Concentração de Íons de Hidrogênio , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Microalgas/metabolismo , Óxido Nítrico/isolamento & purificação , Óxido Nítrico/toxicidade , Dióxido de Enxofre/isolamento & purificação , Dióxido de Enxofre/toxicidade
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