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1.
ACS Chem Neurosci ; 14(3): 389-399, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634245

RESUMO

The increase in proinflammatory cytokine expression causes behavioral changes consistent with sickness behavior, and this led to the suggestion that depression might be a psychoneuroimmunological phenomenon. Here, we evaluated the effects of the pretreatment with fluoxetine (10 mg/kg, i.p.) and curcumin (0.5 mg/kg, i.p.) on the immune response elicited by the inoculation of an Aeromonas hydrophila bacterin in zebrafish. Non-pretreated but A. hydrophila-inoculated and sham-inoculated groups of fish served as controls. The social preference, locomotor, exploratory activities, and cerebral expression of il1b, il6, tnfa, and bdnf mRNA were compared among the groups. Behavioral changes characteristic of sickness behavior and a significant increase in the expression of il1b and il6 cytokines were found in fish from the immunostimulated group. The behavioral alterations caused by the inflammatory process were different between males and females, which was coincident with the increased expression of cerebral BDNF. Fluoxetine and curcumin prevented the sickness behavior induced by A. hydrophila and the increased expression of proinflammatory cytokines. Our results point to the potential of zebrafish as a translational model in studies related to neuroinflammation and demonstrate for the first time the effects of fluoxetine and curcumin on zebrafish sickness behavior.


Assuntos
Curcumina , Fluoxetina , Masculino , Animais , Feminino , Fluoxetina/farmacologia , Citocinas/metabolismo , Peixe-Zebra/metabolismo , Curcumina/farmacologia , Fator Neurotrófico Derivado do Encéfalo , Interação Social , Interleucina-6
2.
Pharmacol Rep ; 74(4): 736-744, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35852770

RESUMO

BACKGROUND: Curcumin, a polyphenol extracted from the rhizome of Curcuma longa L. (Zingiberaceae), presents neuroprotective properties and can modulate neuronal pathways related to mental disorders. However, curcumin has low bioavailability, which can compromise its use. The micronization process can reduce mean particle diameter and improve this compound's bioavailability and therapeutic potential. METHODS: We compared the behavioral (open tank test, OTT) and neurochemical (thiobarbituric acid reactive substances (TBARS) and non-protein thiols (NPSH) levels) effects of non-micronized curcumin (CUR, 10 mg/kg, ip) and micronized curcumin (MC, 10 mg/kg, ip) in adult zebrafish subjected to a 90-min acute restraint stress (ARS) protocol. RESULTS: ARS increased the time spent in the central area and the number of crossings and decreased the immobility time of the animals in the OTT. These results suggest an increase in locomotor activity and a decrease in thigmotaxis behavior. Both CUR and MC were not able to prevent these effects. Furthermore, ARS also induced oxidative damage by increasing TBARS and decreasing NPSH levels. Both CUR and MC did not prevent these effects. CONCLUSION: ARS-induced behavioral and biochemical effects were not blocked by any curcumin preparation. Therefore, we conclude that curcumin does not have acute anti-stress effects in zebrafish.


Assuntos
Curcumina , Animais , Antioxidantes/farmacologia , Curcumina/farmacologia , Curcumina/uso terapêutico , Humanos , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico , Peixe-Zebra
3.
Inflammopharmacology ; 30(1): 327-341, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35006455

RESUMO

Curcumin presents a promising anti-inflammatory potential, but its low water-solubility and bioavailability hinder its application. In this sense, cocrystallization represents a tool for improving physicochemical properties, solubility, permeability, and bioavailability of new drug candidates. Thus, the aim of this work was to produce curcumin cocrystals (with n-acetylcysteine as coformer, which possesses anti-inflammatory and antioxidant activities), by the anti-solvent gas technique using supercritical carbon dioxide, and to test its antinociceptive and anti-inflammatory potential. The cocrystal was characterized by differential scanning calorimetry, powder X-ray diffraction and scanning electron microscopy. The cocrystal solubility and antichemotaxic activity were also assessed in vitro. Antinociceptive and anti-inflammatory activities were carried out in vivo using the acetic acid-induced abdominal writhing and carrageenan-induced paw oedema assays in mice. The results demonstrated the formation of a new crystalline structure, thereby confirming the successful formation of the cocrystal. The higher solubility of the cocrystal compared to pure curcumin was verified in acidic and neutral pH, and the cocrystal inhibited the chemotaxis of neutrophils in vitro. In vivo assays showed that cocrystal presents increased antinociceptive and anti-inflammatory potency when compared to pure curcumin, which could be related to an improvement in its bioavailability.


Assuntos
Curcumina , Acetilcisteína/farmacologia , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Cristalização/métodos , Curcumina/farmacologia , Camundongos , Solubilidade , Solventes/química
4.
Appl Biochem Biotechnol ; 194(5): 2151-2167, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35050455

RESUMO

Lipases are an important group of biocatalysts for many industrial applications. Two new commercial low-cost lipases Eversa® Transform and Eversa® Transform 2.0 was immobilized on four different hydrophobic supports: Lewatit-DVB, Purolite-DVB, Sepabeads-C18, and Purolite-C18. The performance of immobilized lipases was investigated in the transesterification of sunflower oil solvent-free in an anhydrous medium. Interesting results were obtained for both lipases and the four supports, but with Sepabeads support the lipases Eversa showed high catalytic activity. However, the more stable and efficient derivative was Eversa® Transform immobilized on Sepabeads C-18. A 98 wt% of ethyl ester of fatty acid (FAEE) was obtained, in 3 h at 40ºC, ethanol/sunflower oil molar ratio of 3:1 and a 10 wt% of the immobilized biocatalyst. After 6 reaction cycles, the immobilized biocatalyst preserved 70 wt% of activity. Both lipases immobilized in Sepabeads C-18 were highly active and stable in the presence of ethanol. The immobilization of Eversa Transform and Eversa Transform 2.0 in hydrophobic supports described in this study appears to be a promising alternative to the immobilization and application of these news lipases still unexplored.


Assuntos
Enzimas Imobilizadas , Lipase , Enzimas Imobilizadas/química , Etanol/química , Lipase/química , Solventes , Óleo de Girassol/química
5.
Appl Biochem Biotechnol ; 193(11): 3512-3527, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34292478

RESUMO

In this research, eugenyl acetate, a compound with flavoring, antioxidant, and antimicrobial properties, was obtained from essential oil of clove (Syzygium aromaticum) via liquid lipase-mediated acetylation. Clove essential oil was extracted by drag water vapor from dry flower buds and its physic-chemical characteristics were analyzed. For the enzymatic synthesis, an extensive evaluation of reaction parameters was accomplished through employment of distinct reaction temperatures, acetic anhydride to eugenol molar ratios, enzyme loads, and three different lipases (a lyophilized enzyme produced by solid-state fermentation of sunflower seed with Penicillium sumatrense microorganism and other two commercial lipases - Lipozyme TL 100L and CALB L). The product eugenyl acetate was confirmed by 1H-NMR, 13C-NMR Distortionless Enhancement by Polarization Transfer (DEPT 135), and Heteronuclear Multiple Bond Correlation (HMBC). Through optimized conditions (55 °C, acetic anhydride to eugenol molar ratio of 1:1, 10 wt% of Lipozyme TL 100L), 91.80% of conversion after 2 h was achieved to the eugenyl acetate production. With the results obtained, it was possible to conclude that the use of lipases in liquid formulation is a promising alternative for the synthesis of essential esters largely applied on food, cosmetic, and pharmaceutical industries.


Assuntos
Eugenol/análogos & derivados , Proteínas Fúngicas/química , Lipase/química , Óleos Voláteis/química , Penicillium/enzimologia , Syzygium/química , Biocatálise , Eugenol/síntese química , Eugenol/química
6.
Biomed J ; 44(6 Suppl 1): S63-S72, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35747996

RESUMO

BACKGROUND: A. gratissima is a shrub used in folk medicine as analgesic and sedative. However, studies on its antinociceptive activity are scarce. This research aimed to evaluate the antinociceptive effect of a supercritical carbon dioxide (SCCO2) extract of A. gratissima leaves (EAG) in mice. METHODS: A. gratissima leaves were subjected to extraction with supercritical CO2 (60 °C, 200 bar). The chemical composition of EAG was determined by gas chromatography-mass spectrometry (GC-MS). The antinociceptive profile of the extract (1, 10 and 30 mg/kg, p.o.) was established using acetic acid-induced abdominal contraction tests and formalin-induced paw-licking tests. The open field and rota-rod tests were used to evaluate a possible interference of EAG on mice motor performance. The contribution of the opioid system and adenosine triphosphate (ATP) sensitive K+ channels in the mechanism(s) of EAG action was evaluated by specific receptor blockers. EAG's acute toxicity was investigated using OECD 423 guideline. RESULTS: The GC-MS revealed the presence of sesquiterpenes (guaiol and pinocamphone) in the EAG. Doses of 10 mg/kg and 30 mg/kg significantly reduced the number of abdominal writhes and paw licking time in mice in the formalin test. The EAG did not affect the locomotor activity and motor coordination of the mice. The antinociceptive effect of the EAG was prevented by glibenclamide in the mice formalin test, unlike naloxone pre-treatment. The acute administration of EAG caused no mortality. CONCLUSION: A. gratissima leaves possess antinociceptive effect, mediated by K+ channels sensitive to ATP.


Assuntos
Analgésicos , Extratos Vegetais , Verbenaceae , Analgésicos/farmacologia , Animais , Dióxido de Carbono , Canais KATP/metabolismo , Camundongos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Verbenaceae/química
7.
Neurochem Res ; 46(2): 241-251, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33108629

RESUMO

Epilepsy affects 50 million people around the world, and the patients experience cognitive, psychological and social consequences. Despite the considerable quantity of antiepileptic drugs available, 30% of patients still suffer in seizure. Therefore, the advance in therapeutic alternatives is mandatory. Resveratrol has been attracting the attention of many researchers because of its pharmacological potential. However, despite its neuroprotective and anti-epileptic effects, clinical resveratrol use is impaired by its low bioavailability. Here, we applied the supercritical fluid micronization technology (SEDS) to overcome this deficit, and investigated the anticonvulsant potential of micronized resveratrol in a PTZ-induced seizure model in adult zebrafish (Danio rerio). SEDS permits obtaining significantly reduced particle size with a fine size distribution in comparison with the starting material. It can improve the pharmacotherapeutic efficacy. Our data showed that micronized resveratrol decreased the occurrence of the tonic-clonic seizure stage and slowed the development of the seizures in a similar manner of diazepam. Non-processed resveratrol was not able to protect the animals. Furthermore, diazepam decreased the locomotion and exploratory behavior. Differently from diazepam, the micronized resveratrol did not induce behavioral adverse events. In addition, our data showed that the PTZ-induced seizures increased the c-fos transcript levels following the neural excitability. However, the increase in c-fos levels was prevented by micronized resveratrol. In conclusion, our results demonstrate that the micronized resveratrol shows anticonvulsant effect, like the classical antiepileptic drug diazepam in a PTZ-induced seizure model. Excitingly, different from diazepam, micronized resveratrol did not provoke behavioral adverse events.


Assuntos
Anticonvulsivantes/uso terapêutico , Resveratrol/uso terapêutico , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/química , Diazepam/uso terapêutico , Feminino , Locomoção/efeitos dos fármacos , Masculino , Tamanho da Partícula , Pentilenotetrazol , Proteínas Proto-Oncogênicas c-fos/metabolismo , Resveratrol/química , Convulsões/induzido quimicamente , Peixe-Zebra
8.
Food Chem ; 344: 128620, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33223301

RESUMO

This work investigated the efficiency of pressurized liquid extraction (PLE) and supercritical fluid extraction with cosolvent (SFE) in obtaining feijoa leaf extracts with high antioxidant and antibacterial activities. PLE was performed in customized equipment with environmentally friendly solvents, at 40/80 °C, in dynamic and static mode, and SFE was carried out for 210 min at 30 MPa, 55 °C and 15% ethanol-water as cosolvent. PLE extract (80 °C/ethanol-water/dynamic) provided the highest yield, total phenolic content, and antioxidant activities, but it was not effective as antibacterial agent. In contrast, SFE extract exhibited effectiveness against S. aureus, E. coli, and S. typhimurium, with minimum inhibitory concentration values from 14,211 to 3,553 µg.mL-1. Finally, gallic acid, catechin and isoquercetin were the major phenolics identified by liquid chromatography. Our findings revealed that feijoa leaf extracts by PLE and SFE have remarkable bioactivity, presenting a great potential to be used as natural food additives.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Fracionamento Químico/métodos , Feijoa/química , Extratos Vegetais/química , Antibacterianos/química , Antioxidantes/química , Cromatografia com Fluido Supercrítico/métodos , Escherichia coli/efeitos dos fármacos , Etanol/química , Testes de Sensibilidade Microbiana , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/farmacologia , Pressão , Solventes/química , Staphylococcus aureus/efeitos dos fármacos
9.
Epilepsy Res ; 159: 106243, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31786493

RESUMO

Resveratrol is a natural non-flavonoid polyphenolic that has been emerging in epilepsy treatment. Despite its pharmacological properties, the poor bioavailability of resveratrol has been an important barrier that hinders its application as an anticonvulsant. The aim of this work was to improve resveratrol's anticonvulsant effects by micronizing this compound through supercritical fluid micronization technology, which promotes an increase of the particles' surface area and allows significantly reduced particle size to be obtained. We obtained commercial and micronized resveratrol and investigated the anticonvulsant effects of resveratrol as commercially found and micronized resveratrol in a pentylenetetrazole-induced seizure model in zebrafish (Danio rerio) larvae. Diazepam was used as the positive control. Also, animals had their locomotor and exploratory activity analyzed 24 h after the seizure occurrence. The occurrence of the tonic-clonic seizure stage was only prevented by diazepam and micronized resveratrol, unlike the non-processed compound. The seizure development was significantly slowed by diazepam and micronized resveratrol, while non-micronized resveratrol was not able to increase the latency of seizure stages. In addition, diazepam and micronized resveratrol prevented the deleterious effects of pentylenetetrazole-induced seizures on animals' locomotor and exploratory behaviour. Obtained data demonstrates that the micronization process potentiates the anticonvulsant effect of resveratrol. Micronized resveratrol achieved a similar effect to the classical drug diazepam, with the benefit that it may be a safe drug candidate to be used during the neurodevelopmental stage.


Assuntos
Anticonvulsivantes/uso terapêutico , Resveratrol/uso terapêutico , Convulsões/tratamento farmacológico , Animais , Modelos Animais de Doenças , Pentilenotetrazol , Convulsões/induzido quimicamente , Resultado do Tratamento , Peixe-Zebra
10.
Appl Biochem Biotechnol ; 188(4): 914-926, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30729422

RESUMO

The performance of lipase NS 40116, a novel and promising soluble enzyme obtained from modified Thermomyces lanuginosus microorganism, was investigated in the production of biodiesel (fatty acid methyl esters-FAME) by hydroesterification. In order to investigate the potential of the biocatalyst in its soluble form, this work reports the effect of water content and enzyme load, as well as the recovery and reuse of the biocatalyst. A FAME yield of 94.30% after 12 h was achieved at 35 °C by combining 0.50 wt% of lipase, 15 wt% of water, and a methanol:oil molar ratio of 4.5:1. The analysis of the time course reaction suggests that the triacylglycerides (TAGs) are hydrolyzed by the enzyme in a first step, generating free fatty acids (FFAs), followed by the esterification of these FFAs into FAME. In relation to the reusability assays, the lipase kept approximately 90% of its catalytic activity after five cycles of reuse. In this context, the findings of this study demonstrate that lipase NS 40116 can efficiently catalyze hydroesterification reactions under mild conditions, arising as a competitive alternative for biodiesel synthesis.


Assuntos
Biocombustíveis , Lipase/metabolismo , Proteínas de Plantas/metabolismo , Óleo de Soja/metabolismo , Catálise , Hidrólise , Óleo de Soja/química
11.
Appl Biochem Biotechnol ; 185(3): 705-716, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29297136

RESUMO

The performance of two new commercial low-cost lipases Eversa® Transform and Eversa® Transform 2.0 immobilized in different supports was investigated. The two lipases were adsorbed on four different hydrophobic supports. Interesting results were obtained for both lipases and for the four supports. However, the most active derivative was prepared by immobilization of Eversa® Transform 2.0 on Sepabeads C-18. Ninety-nine percent of fatty acid ethyl ester was obtained, in 3 h at 40 °C, by using hexane as solvent, a molar ratio of 4:1 (ethanol/oil), and 10 wt% of immobilized biocatalyst. The final reaction mixture contained traces of monoacylglycerols but was completely free of diacylglycerols. After four reaction cycles, the immobilized biocatalyst preserved 75% of activity. Both lipases immobilized in Sepabeads C-18 were very active with ethanol and methanol as acceptors, but they were much more stable in the presence of ethanol.


Assuntos
Enzimas Imobilizadas/química , Etanol/química , Ácidos Graxos/biossíntese , Lipase/química , Óleo de Girassol/química , Biocatálise , Cromatografia Líquida de Alta Pressão , Diglicerídeos/análise , Esterificação , Ésteres , Hexanos/química , Interações Hidrofóbicas e Hidrofílicas , Monoglicerídeos/análise , Polímeros/química
12.
J Food Sci Technol ; 54(1): 98-104, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28242908

RESUMO

Traditionally, Ilex paraguariensis leaves are consumed in tea form or as typical drinks like mate and terere, while the fruits are discarded processing and has no commercial value. The aim of this work to evaluate phytochemical properties, total phenolic compounds, antioxidant and antimicrobial activity of extracts of Ilex paraguariensis fruits obtained from supercritical CO2 and compressed propane extraction. The extraction with compressed propane yielded 2.72 wt%, whereas with supercritical CO2 1.51 wt% was obtained. The compound extracted in larger amount by the two extraction solvents was caffeine, 163.28 and 54.17 mg/g by supercritical CO2 and pressurized propane, respectively. The antioxidant activity was more pronounced for the supercritical CO2 extract, with no difference found in terms of minimum inhibitory concentration for Staphylococcus aureus for the two extracts and better results observed for Escherichia coli when using supercritical CO2.

13.
J Food Sci Technol ; 54(3): 846-851, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28298700

RESUMO

The extraction of litchi (Litchi chinensis Sonn.) and oat (Avena sativa L.) seeds were investigated using n-butane as pressurized solvent by evaluating the effect of pressure in the range of 7-100 bar and temperature from 25 to 70 °C on the extract yield and chemical composition together with the antioxidant activity of the extracts obtained. It was experimentally observed extraction yields for both seeds up to ~3.5 wt%, with a total phenolic content around 126.4 mg GAE/100 g of extract, and an antioxidant activity up to 78.36%. Oat seeds extract presented higher values of these parameters evaluated compared to litchi extract. Based on the results found, it seems that n-butane may be a promising solvent to conventional extraction methods, as mild operating conditions and eco-friendly solvent can be used to provide good results without any residues in the final product.

14.
Environ Technol ; 38(16): 1969-1979, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27735225

RESUMO

This work investigates the use of ceramic membranes with different molecular weight cut-offs (MWCOs: 5, 10 and 20 kDa) to desolventize azeotropic solvent mixtures (ethanol/n-hexane and isopropyl alcohol/n-hexane) from soybean oil/azeotrope micelles. Results show that a decrease in the MWCO of a membrane and an increase in the solvent mass ratio in the mixture resulted in a significant reduction in the permeate flux. The 20 kDa membrane presented the highest permeate flux, 80 and 60 kg/m2h for the soybean oil/n-hexane/isopropyl alcohol and soybean oil/n-hexane/ethanol azeotropes, respectively, for an oil to solvent ratio of 1:3 (w/w). The highest oil retention was found using the n-hexane/isopropyl alcohol azeotrope, around 25% in the membrane with the lowest MWCO, that is, 5 kDa. It is shown that the azeotropic mixtures provided intermediate characteristics compared to the original pure solvent behavior.


Assuntos
Cerâmica , Óleo de Soja , 2-Propanol , Membranas Artificiais , Solventes
15.
Bioprocess Biosyst Eng ; 38(8): 1447-53, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25759162

RESUMO

Some of the noxious atmospheric pollutants such as nitrogen and sulfur dioxides come from the fossil fuel combustion. Biodesulfurization and biodenitrogenation are processes which remove those pollutants through the action of microorganisms. The ability of sulfur and nitrogen removal by the strain Rhodococcus erythropolis ATCC 4277 was tested in a biphasic system containing different heavy gas oil concentrations in a batch reactor. Heavy gas oil is an important fraction of petroleum, because after passing through, the vacuum distillation is incorporated into diesel oil. This strain was able to remove about 40% of the nitrogen and sulfur present in the gas heavy oil. Additionally, no growth inhibition occurred even when in the presence of pure heavy gas oil. Results present in this work are considered relevant for the development of biocatalytic processes for nitrogen and sulfur removal toward building feasible industrial applications.


Assuntos
Gases/metabolismo , Dióxido de Nitrogênio/metabolismo , Petróleo , Rhodococcus/crescimento & desenvolvimento , Dióxido de Enxofre/metabolismo
16.
Bioprocess Biosyst Eng ; 38(3): 437-48, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25362889

RESUMO

This work reports the transesterification of soybean oil with ethanol using a commercial immobilized lipase, Novozym 435, under the influence of ultrasound irradiation, in a solvent-free s. The experiments were performed in an ultrasonic water bath, following a sequence of experimental designs to evaluate the effects of temperature, enzyme and water concentrations, oil to ethanol molar ratio and output irradiation power on the reaction yield. Besides, a kinetic study varying the substrates molar ratio and enzyme concentration was also carried out. Results show that ultrasound-assisted lipase-catalyzed transesterification of soybean oil with ethanol in solvent-free system might be a potential alternative route to conventional alkali-catalyzed and/or traditional enzymatic methods, as high reaction yields (~78 wt%) were obtained at mild irradiation power supply (~132 W), and temperature (63 °C) in a relatively short reaction time, 1 h. Additionally, a study regarding the enzyme reuse was carried out at the experimental condition that afforded the best reaction yield.


Assuntos
Biocombustíveis , Lipase/química , Som , Óleo de Soja/química , Catálise , Enzimas Imobilizadas , Proteínas Fúngicas
17.
Bioprocess Biosyst Eng ; 37(5): 841-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24078183

RESUMO

This work investigates the continuous production of alkyl esters from soybean fatty acid (FA) charges using immobilized Novozym 435 as catalyst. The experiments were performed in a packed-bed bioreactor evaluating the effects of FA charge to alcohol (methanol and ethanol) molar ratio, from 1:1 to 1:6, substrate flow rate in the range of 0.5-2.5 mL/min and output irradiation power up to 154 W, at fixed temperature of 65 °C, on the reaction conversion. Results showed that almost complete conversions to fatty acids ethyl esters were achieved at mild ultrasonic power (61.6 W), FA to ethanol molar ratio of 1:6, operating temperature (65 °C) and remained nearly constant for long-term reactions without negligible enzyme activity losses.


Assuntos
Ácidos Graxos/química , Glycine max/química , Lipase/química , Som , Enzimas Imobilizadas , Esterificação , Proteínas Fúngicas , Temperatura Alta
18.
Braz. j. microbiol ; 45(1): 294-301, 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-709490

RESUMO

Lipases produced by a newly isolated Sporidiobolus pararoseus strain have potential catalytic ability for esterification reactions. After production, the enzymatic extracts (conventional crude and precipitated, 'CC' and 'CP', and industrial crude and precipitated, 'IC' e 'IP') were partially characterized. The enzymes presented, in general, higher specificity for short chain alcohols and fatty acids. The precipitated extract showed a good thermal stability, higher than that for crude enzymatic extracts. The 'CC' and 'CP' enzymes presented high activities after exposure to pH 6.5 and 40 ºC. On the other hand, the 'IC' and 'IP' extracts kept their activities in a wide range of pH memory but presented preference for higher reaction temperatures. Preliminary studies of application of the crude lipase extract in the enzymatic production of geranyl propionate using geraniol and propionic acid as substrates in solvent-free system led to a reaction conversion of 42 ± 1.5%.


Assuntos
Basidiomycota/enzimologia , Lipase/isolamento & purificação , Lipase/metabolismo , Álcoois/metabolismo , Basidiomycota/crescimento & desenvolvimento , Estabilidade Enzimática , Ácidos Graxos/metabolismo , Concentração de Íons de Hidrogênio , Lipase/química , Especificidade por Substrato , Temperatura
19.
Braz. j. microbiol ; 43(4): 1490-1498, Oct.-Dec. 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-665836

RESUMO

The lipase produced by a newly isolate Sporidiobolus pararoseus strain has potential catalysis ability for esterification reactions. In order to improve its synthetic activity, this work aimed at optimizing 'synthetic lipase' production by submerged fermentation of a conventional media based on peptone, yeast extract, NaCl and olive oil using experimental design technique. According to the results obtained in the first experimental design (2(4-1)), yeast extract and NaCl concentrations were tested to further optimization by response surface methodology. The maximum 'synthetic lipase' activity obtained was 26.9 U/mL in the optimized media (5.0, 6.8, 7.0 and 1.0% (wt/v) of peptone, yeast extract, NaCl and olive oil, respectively), representing a 6.36-fold increase compared to the initial medium. The time course of 'synthetic lipase' production in the optimized condition was evaluated in terms of synthetic activity, protease activity, biomass and total carbon and the maximum synthetic activity was observed during the stationary phase of growth.


Assuntos
Sequência de Bases , Blastomyces/isolamento & purificação , Fermentação , Fungos Mitospóricos/genética , Fungos Mitospóricos/isolamento & purificação , Leveduras/isolamento & purificação , Lipase/análise , Lipase/isolamento & purificação , Ativação Enzimática , Microbiologia Industrial , Metodologia como Assunto
20.
Appl Biochem Biotechnol ; 166(1): 13-21, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21976151

RESUMO

Enzymatic esterification of citronella essential oil towards the production of geranyl and citronellyl esters may present great scientific and technological interest due to the well-known drawbacks of the chemical-catalyzed route. In this context, this work reports the maximization of geranyl and citronellyl esters production by esterification of oleic and propionic acids in a solvent-free system using a commercial immobilized lipase as catalyst. Results of the reactions showed that the strategy adopted for the experimental design proved to be useful in evaluating the effects of the studied variables on the reaction conversion using Novozym 435 as catalyst. The operating conditions that maximized the production of each ester were determined, leading, in a general way, to conversions of about 90% for all systems. New experimental data on enzymatic esterification of crude citronella essential oil for geranyl and citronellyl esters production in solvent-free system are reported in this work.


Assuntos
Cymbopogon/química , Aromatizantes/síntese química , Óleos Voláteis/química , Esterificação , Solventes/química
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