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1.
Biotechnol Lett ; 44(3): 439-459, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35147845

RESUMO

Endophytic fungi are microorganisms capable of colonizing the interior of plant tissues without causing damage to them. The study of the secondary metabolites produced by their vast biodiversity fungal is relevant for the discovery of new products for biotechnological and agrochemical applications. In addition, extract of the endophytic fungus Aspergillus sp., isolated from the almonds of Bertholletia excelsa Humn & Bonlp collected in the Brazilian Amazon, oviposition deterrent, and larvicidal activity of against Aedes aegypti. In the oviposition deterrence test was observed that females able to lay eggs preferred the control oviposition sites (46.6%). Furthermore, the extract showed larvicidal activity with LC50 26.86 µg/mL at 24 h and 18.75 µg/mL at 48 h. Molecular docking studies showed the compound Aspergillol B a potent larvicide by to inhibit the acetylcholinesterase enzyme (- 7.74 kcal/mol). These results indicate that compounds from secondary metabolites of Aspergillus sp., isolated from almonds of B. excelsa, are useful biological potential against vectors A. aegypti.


Assuntos
Aedes , Bertholletia , Inseticidas , Acetilcolinesterase , Animais , Aspergillus , Feminino , Inseticidas/farmacologia , Larva , Simulação de Acoplamento Molecular , Mosquitos Vetores , Extratos Vegetais/farmacologia
2.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500534

RESUMO

Mosquitoes can be vectors of pathogens and transmit diseases to both animals and humans. Species of the genus Culex are part of the cycle of neglected diseases, especially Culex quinquefasciatus, which is an anthropophilic vector of lymphatic filariasis. Natural products can be an alternative to synthetic insecticides for vector control; however, the main issue is the poor water availability of some compounds from plant origin. In this context, nanoemulsions are kinetic stable delivery systems of great interest for lipophilic substances. The objective of this study was to investigate the larvicidal activity of the Hyptis suaveolens essential oil nanoemulsion on Cx. quinquefasciatus. The essential oil showed a predominance of monoterpenes with retention time (RT) lower than 15 min. The average size diameter of the emulsions (sorbitan monooleate/polysorbate 20) was ≤ 200 nm. The nanoemulsion showed high larvicidal activity in concentrations of 250 and 125 ppm. CL50 values were 102.41 (77.5253−149.14) ppm and 70.8105 (44.5282−109.811) ppm after 24 and 48 h, respectively. The mortality rate in the surfactant control was lower than 9%. Scanning micrograph images showed changes in the larvae's integument. This study achieved an active nanoemulsion on Cx. quinquefasciatus through a low-energy-input technique and without using potentially toxic organic solvents. Therefore, it expands the scope of possible applications of H. suaveolens essential oil in the production of high-added-value nanosystems for tropical disease vector control.


Assuntos
Aedes , Culex , Culicidae , Inseticidas , Lamiaceae , Óleos Voláteis , Humanos , Animais , Óleos Voláteis/farmacologia , Óleos Voláteis/análise , Larva , Mosquitos Vetores , Inseticidas/química , Extratos Vegetais/química , Folhas de Planta/química
3.
Molecules ; 24(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546839

RESUMO

Brown macroalgae, particularly those from Fucus genus, are a rich and balanced source of bioactive nutrients and phytochemicals, such as dietary fibres (fucoidans, laminarins, and/or alginates), phlorotannins, and fucoxanthin, and some minerals, such as iodine, which have been demonstrated to possess numerous health-promoting properties. In fact, aqueous extracts of Fucus vesiculosus have been used as food supplements due to its rich content in bioactive compounds, though no study has been published on the optimization of this operation. Therefore, this study aimed to evaluate the impact of different extraction temperatures (25 °C, 50 °C, 75 °C, 100 °C, and 120 °C) and times (5 min, 1 h, 2 h, and 4 h) on the recovery of those bioactive compounds. The temperature was observed to positively influence the extraction of crude mass and of fucose polysaccharides only at 75 °C and above, and of iodine extraction at 50 °C and above. At these temperatures, time also showed to increase yields. Yields of crude extract, fucose, and iodine were successfully mathematically modelled with a power law, and its maximum yields were obtained at the highest temperature studied (120 °C) and longest extraction time (4 h). Iodine yield at these conditions provided extracts with relevant content to contribute to the recommended daily ingestion. Phlorotannins were significantly recovered at 120 °C though evidence of degradation was observed during time.


Assuntos
Fucus/química , Compostos Fitoquímicos/isolamento & purificação , Água/química , Benzotiazóis/química , Misturas Complexas , Sequestradores de Radicais Livres/química , Fucose/análise , Iodo/análise , Cinética , Ácidos Sulfônicos/química
4.
J Nanobiotechnology ; 15(1): 2, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049483

RESUMO

BACKGROUND: Preparation of nanoformulations using natural products as bioactive substances is considered very promising for innovative larvicidal agents. On this context, oil in water nanoemulsions develop a main role, since they satisfactorily disperse poor-water soluble substances, such as herbal oils, in aqueous media. Pterodon emarginatus, popularly known as sucupira, has a promising bioactive oleoresin. However, to our knowledge, no previous studies were carried out to evaluate its potential against Culex quinquefasciatus, the main vector of the tropical neglected disease called lymphatic filariasis or elephantiasis. Thus, we aimed to investigate influence of different pairs of surfactants in nanoemulsion formation and investigate if a sucupira oleoresin-based nanoemulsion has promising larvicidal activity against this C. quinquefasciatus. We also evaluated morphological alteration, possible mechanism of insecticidal action and ecotoxicity of the nanoemulsion against a non-target organism. RESULTS: Among the different pairs of surfactants that were tested, nanoemulsions obtained with polysorbate 80/sorbitan monooleate and polysorbate 80/sorbitan trioleate presented smallest mean droplet size just afterwards preparation, respectively 151.0 ± 2.252 and 160.7 ± 1.493 nm. They presented high negative zeta potential values, low polydispersity index (<0.300) and did not present great alteration in mean droplet size and polydispersity index after 1 day of preparation. Overall, nanoemulsion prepared with polysorbate 80/sorbitan monooleate was considered more stable and was chosen for biological assays. It presented low LC50 value against larvae (34.75; 7.31-51.86 mg/L) after 48 h of treatment and some morphological alteration was observed. The nanoemulsion did not inhibit acetylcholinesterase of C. quinquefasciatus larvae. It was not toxic to green algae Chlorella vulgaris at low concentration (25 mg/L). CONCLUSIONS: Our results suggest that optimal nanoemulsions may be prepared with different surfactants using a low cost and low energy simple method. Moreover, this prototype proved to be effective against C. quinquefasciatus, being considered an ecofriendly novel nanoproduct that can be useful in integrated control programs of vector control.


Assuntos
Culicidae/efeitos dos fármacos , Emulsões/toxicidade , Fabaceae/química , Controle de Insetos , Inseticidas/toxicidade , Extratos Vegetais/toxicidade , Animais , Chlorella vulgaris/efeitos dos fármacos , Chlorella vulgaris/fisiologia , Culicidae/fisiologia , Emulsões/química , Feminino , Inseticidas/química , Larva/efeitos dos fármacos , Larva/fisiologia , Extratos Vegetais/química
5.
Foodborne Pathog Dis ; 13(8): 423-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27149657

RESUMO

Cheese whey fermented by an industrial starter consortium of lactic acid bacteria was evaluated for its antibacterial capacity to control a selection of pathogenic bacteria. For their relevance on outbreak reports related to vegetable consumption, this selection included Listeria monocytogenes, serotype 4b, Escherichia coli O157:H7, and Salmonella Goldcoast. Organically grown lettuce was inoculated with an inoculum level of ∼10(7) colony-forming unit (CFU)/mL and was left for about 1 h in a safety cabinet before washing with a perceptual solution of 75:25 (v/v) fermented whey in water, for 1 and 10 min. Cells of pathogens recovered were then counted and their number compared with that obtained for a similar treatment, but using a chlorine solution at 110 ppm. Results show that both treatments, either with chlorine or fermented whey, were able to significantly reduce (p < 0.05) the number of bacteria, in a range of 1.15-2.00 and 1.59-2.34 CFU/g, respectively, regarding the bacteria tested. Results suggest that the use of fermented whey may be as effective as the solution of chlorine used in industrial processes in reducing the pathogens under study (best efficacy shown for Salmonella), with the advantage of avoiding health risks arising from the formation of carcinogenic toxic chlorine derivates.


Assuntos
Desinfecção/métodos , Escherichia coli O157/isolamento & purificação , Lactuca/microbiologia , Listeria monocytogenes/isolamento & purificação , Salmonella/isolamento & purificação , Soro do Leite , Antibacterianos , Carga Bacteriana , Queijo , Desinfetantes , Fermentação , Microbiologia de Alimentos , Hipoclorito de Sódio , Soluções
6.
Mediterr J Rheumatol ; 34(2): 188-219, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37654628

RESUMO

Objective/Aims: The aims of this study are to collect the most common non-pharmacological and non-surgical interventions used by the Portuguese physical therapists in their knee osteoarthritis patients, and to deeper understand the factors associated to their intervention choices. Methods: This study incorporated a mixed-methods design. For the quantitative data it was choose an e-survey (with 25 close-end questions, plus general information of the study and a clinical vignette), retrieving sociodemographic and self-reported practice on knee osteoarthritis information. It was analysed response frequencies and associations between variables with logistic regression analyses. For the qualitative data, it was chosen to perform semi-structured interviews in purposefully selected physical therapists to include different sociodemographic factors and survey responses regarding the physical therapists' interventions chosen. After the interviews, the audios were collected, anonymised, transcribed verbatim, and the texts explored by the thematic approach. Results: From the 277 PTs that shown interest in participating in the study, 120 fully completed the questionnaire and, from those, 10 participated in the interviews. The most chosen interventions included Resistance Exercise, Manual Therapy, Nutrition/Weight Loss, Self-care/Education, Stretching and Aquatic Exercise. Furthermore, it seems that PTs' individual characteristics (age, experience, and clinical reasoning), patient's characteristics (clinical findings and preferences), and work-related factors (facility type, work environment and available resources) are the main actors responsible for an intervention chosen. Conclusions: In the Portuguese PTs context the most important interventions are Exercise, Manual Therapy, Nutrition/Weight Loss, and Self-care/Education; these interventions chosen may be influenced by PT, patient and work-related factors.

7.
J Biophotonics ; 16(1): e202200185, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36054631

RESUMO

The increase of tissue transparency through sequential optical immersion clearing treatments and treatment reversibility have high interest for clinical applications. To evaluate the clearing reversibility in a broad spectral range and the magnitude of the transparency created by a second treatment, the present study consisted on measuring the spectral collimated transmittance of lung tissues during a sequence of two treatments with electronic cigarette (e-cig) fluid, which was intercalated with an immersion in saline. The saline immersion clearly reverted the clearing effect in the lung tissue in the spectral range between 220 and 1000 nm. By a later application of a second treatment with the e-cig fluid, the magnitude of the optical clearing effect was observed to be about the double as the one observed in the first treatment, showing that the molecules of the optical clearing agent might have converted some bound water into mobile water during the first treatment.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Água/metabolismo , Pulmão , Músculo Esquelético/metabolismo , Espalhamento de Radiação
8.
Foods ; 12(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37297341

RESUMO

Opuntia ficus-indica fruits are a source of valuable compounds, presenting a high nutritional value and several health benefits. However, due to its low shelf life and increased production, there are considerable post-harvest losses of this cactus fruit. So, ways need to be found to drain the increased production of this fruit that is being wasted. The chemical composition of prickly pear makes it an appealing substrate for fermentation. This study investigates the production of fermented beverages produced from Opuntia ficus-indica cv 'Rossa' and evaluates the effects of different fermentation times (18 and 42 h) and post-fermentation pasteurization by high-pressure (500 MPa for 10 min) and temperature (71.1 °C for 30 s) on the physico-chemical and biological characteristics of the produced beverages. According to the results, the beverage produced from 48 h of fermentation has an alcohol content value of 4.90 ± 0.08% (v/v) and a pH of 3.91 ± 0.03. These values contribute to an extended shelf life and improved organoleptic characteristics compared to the sample fermented for 18 h. Additionally, the longer fermentation resulted in 50% fewer total soluble solids, 90% less turbidity, and lower pH when compared to the sample fermented for 18 h. Moreover, overall, high-pressure processing demonstrates better retention of "fresh-like" characteristics, along with higher levels of phytochemical compounds and antioxidant capacity, similar to those observed in the juice for SO•- and NO•-scavenging abilities.

9.
Int J Exerc Sci ; 15(3): 861-883, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991349

RESUMO

Introduction: Currently, the use of self-myofascial release (SMR) instruments is not uncommon in our society, especially in sports. The most common SMR instruments are foam rollers, roller massagers, and balls. Regardless of the instrument used, the main objectives are to enhance performance and recovery. Nevertheless, many studies point out that there is still a lack of robust scientific evidence documenting the exact mechanisms that explain its true effects, therefore some authors affirm that the reported benefits are anecdotal in nature. Objective: This overview aims to summarize, from systematic reviews, the effectiveness of SMR instruments on performance and recovery. Material and Methods: This study followed the PRISMA principles. Systematic reviews were found on the electronic databases according to an established P (healthy active individuals) I (SMR using instruments) C (other treatment, placebo, sham, or no treatment) O (performance and recovery) S (systematic reviews) search strategy. Additionally, methodological analysis was performed using R-AMSTAR. Results: Initially, it was found 15 systematic reviews. However, after methodological analysis, only 7 systematic reviews had sufficient quality to be included. From those, it was found that SMR using instruments is beneficial to enhancing short-term flexibility-related and recovery-related outcomes. Inconstant data was reported in muscular-related outcomes. Nevertheless, beyond pain during SMR, no major adverse effects were found. Different effects between time, pressure and other instrument characteristics were also found. Conclusion: SMR using instruments can be a safe intervention used in sports to enhance performance and recovery from previous training/competition or between matches.

10.
PeerJ ; 9: e12666, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35036149

RESUMO

BACKGROUND: Evidence-based practice (EBP) is considered the "holy grail" to manage patients by health practitioners (such as physical therapists). However, sometimes, patients are not treated with the best interventions for their condition. Although studies already explored the facilitators and barriers for this issue, they increase in the level of importance if the information gathered are context appropriated. As the profession is relatively new in Portugal, currently little is known about the implementation of EBP in Portuguese physical therapists context. So, the aim of this study is to know if the Portuguese physical therapists use an EBP, and collect and deeper understand the factors, barriers and facilitators associated with EBP. METHODS: This study incorporated a mixed-methods design (quantitative and qualitative). In an attempt to ensure the correct population sample, a national professional association e-mail database and the e-mails of past students from national schools were requested. For the quantitative data it was choose an e-survey, adapted from the EBP: Beliefs, Attitudes, Knowledge, and Behaviors of Physical Therapists Portuguese version questionnaire, consisted of 55 close-ended questions. It was analyzed response frequencies and associations between variables with logistic regression analyses. For the qualitative data, it was choose to perform semi-structured interviews in purposefully selected physical therapists to include different sociodemographic factors (especially those found to be statistically significant in the logistic regression) and survey responses regarding the physical therapists' beliefs, attitudes, knowledge, and behaviors. The interviews were performed in an online software, where only audio contact was performed. The audios were anonymized and verbatim transcribed, and the texts explored by the thematic approach. RESULTS: From the 277 physical therapists that shown interest in participating in the study, 193 fully completed the questionnaire and, from those, 10 participated in the interviews. The Portuguese physical therapists reported positive beliefs, attitudes, knowledge, and behaviors regarding EBP. Among the physical therapists characteristics it seems that age (younger therapists), education (participating in continuing education courses; belonging to practice-orientated organizations; having a doctorate degree; pursuing a higher academic degree; and being a clinical instructor), and workplace (working for someone else account; and academic sector) are the main factors in the Portuguese EBP implementation. The Portuguese physical therapists, beyond the physical therapists individual characteristics and workplace, also stated that evidence, patients, clinical experience, schools, country and physical therapy characteristics, may behave as facilitators or barriers when performing an EBP.

11.
Foods ; 11(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35681311

RESUMO

Fucus vesiculosus is a brown seaweed rich in iodine, fucoxanthin, and phlorotannins, all known to be bioactive compounds associated with health-promoting events. The enrichment of a staple food such as pasta with seaweed flour, could convey health benefits without changing eating habits. In this work, F. vesiculosus flour (FVF) was incorporated into durum wheat pasta at 1, 5.5, and 10% gradient levels. The pasta enriched with FVF needed additional water during dough formation and required more cooking time, resulting in higher weight gain but also increased cooking loss (observed with 5.5 and 10%). The fracturability of raw pasta decreased for all the FVF pasta, though the cooked firmness and hardness were only affected with the inclusion of 10% FVF. The substitution of wheat semolina with FVF at a 10% level caused an increase in the pasta's fiber content, which resulted in a more discontinuous protein-matrix structure, as observed at the microscopic level. Untrained consumers were very positive about the overall sensory traits of the pasta with low supplementation levels (1 and 5.5%). About 72% of panelists selected the 1% FVF pasta as their favorite sample. The utilization of FVF in pasta should be targeted at low inclusion levels to cope with the expected texture quality and prevent the impairment of the sensory traits.

12.
Antioxidants (Basel) ; 10(2)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498465

RESUMO

The present work aimed at the valorization of biomass derived compounds by their transformation into new added-value compounds with enhanced antioxidant properties. In this context, betulinic acid (BA) was decorated with polyphenolic fragments, and polyhydroxylated (E)-2-benzylidene-19,28-epoxyoleanane-3,28-diones 4a-d were obtained. For that, the synthetic strategy relied on base-promoted aldol condensation reactions of methyl betulonate, which was previously prepared from natural BA, with appropriate benzaldehydes, followed by cleavage of the methyl protecting groups with BBr3. It is noteworthy that the HBr release during the work-up of the cleavage reactions led to the rearrangement of the lupane-type skeleton of the expected betulonic acid derivatives into oleanane-type compounds 4a-d. The synthesized compounds 4a-d were designed to have specific substitution patterns at C-2 of the triterpene scaffold, allowing the establishment of a structure-activity relationship. The radical scavenging ability of 4a-d was evaluated using the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+) scavenging assays. In particular, derivative 4c, bearing a catechol unit, revealed to be the most efficient scavenger against both free radicals DPPH• and ABTS•+. Subsequently, we designed two analogues of the hit derivative 4c in order to achieve more potent antioxidant agents: (i) the first analogue carries an additional unsaturation in its lateral chain at C-2 (analogue 5) and (ii) in the second analogue, E-ring was kept in its open form (analogue 6). It was observed that the presence of an extended π-conjugated system at C-2 contributed to an increased scavenging effect, since analogue 5 was more active than 6, α-tocopherol, and 4c in the ABTS•+ assay.

13.
Clin Transl Sci ; 13(6): 1137-1149, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32415749

RESUMO

Mycophenolic acid (MPA) is an immunosuppressant commonly used to prevent renal transplant rejection and treat glomerulonephritis. MPA inhibits IMPDH2 within stimulated lymphocytes, reducing guanosine synthesis. Despite the widespread use of MPA, interindividual variability in response remains with rates of allograft rejection up to 15% and approximately half of individuals fail to achieve complete remission to lupus nephritis. We sought to identify contributors to interindividual variability in MPA response, hypothesizing that the HPRT1 salvage guanosine synthesis contributes to variability. MPA sensitivity was measured in 40 healthy individuals using an ex vivo lymphocyte viability assay. Measurement of candidate gene expression (n ± 40) and single-cell RNA-sequencing (n ± 6) in lymphocytes was performed at baseline, poststimulation, and post-MPA treatment. After stimulation, HPRT1 expression was 2.1-fold higher in resistant individuals compared with sensitive individuals (P ± 0.049). Knockdown of HPRT1 increased MPA sensitivity (12%; P ± 0.003), consistent with higher expression levels in resistant individuals. Sensitive individuals had higher IMPDH2 expression and 132% greater stimulation. In lymphocyte subpopulations, differentially expressed genes between sensitive and resistant individuals included KLF2 and LTB. Knockdown of KLF2 and LTB aligned with the predicted direction of effect on proliferation. In sensitive individuals, more frequent receptor-ligand interactions were observed after stimulation (P ± 0.0004), but fewer interactions remained after MPA treatment (P ± 0.0014). These data identify a polygenic transcriptomic signature in lymphocyte subpopulations predictive of MPA response. The degree of lymphocyte stimulation, HPRT1, KLF2, and LTB expression may serve as markers of MPA efficacy.


Assuntos
Imunossupressores/farmacologia , Ativação Linfocitária/genética , Linfócitos/efeitos dos fármacos , Ácido Micofenólico/farmacologia , Adulto , Idoso , Variação Biológica da População/imunologia , Biomarcadores Farmacológicos , Resistência a Medicamentos/genética , Feminino , Regulação da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Voluntários Saudáveis , Humanos , Hipoxantina Fosforribosiltransferase/genética , Imunossupressores/uso terapêutico , Transplante de Rim/efeitos adversos , Fatores de Transcrição Kruppel-Like/genética , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Linfotoxina-beta/genética , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/uso terapêutico , Cultura Primária de Células , RNA-Seq , Análise de Célula Única , Adulto Jovem
14.
Food Res Int ; 115: 352-359, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599952

RESUMO

Saccharomyces cerevisiae is a yeast of great importance in many industries and it has been frequently used to produce food products and beverages. More recently, other uses have also been described for this microorganism, such as the production of bioethanol, as a clean, renewable and sustainable alternative fuel. High pressure processing (HPP) is a technology that has attracted a lot of interest and is increasingly being used in the food industry as a non-thermal method of food processing. However, other applications of high pressure (HP) are being studied with this technology in different areas, for example, for fermentation processes, because microbial cells can resist to pressure sub-lethal levels, due to the development of different adaptation mechanisms. The present work intended to study the adaptation of S. cerevisiae to high pressure, using consecutive cycles of fermentation under pressure (at sub-lethal levels), in an attempt to enhance the production of bioethanol. In this context, three pressure levels (15, 25 and 35 MPa) were tested, with each of them showing different effects on S. cerevisiae fermentation behavior. After each cycle at 15 and 25 MPa, both cell growth and ethanol production showed a tendency to increase, suggesting the adaptation of S. cerevisiae to these pressure levels. In fact, at the end of the 4th cycle, the ethanol production was higher under pressure than at atmospheric pressure (0.1 MPa) (8.75 g.L-1 and 10.69 g.L-1 at 15 and 25 MPa, respectively, compared to 8.02 g.L-1 at atmospheric pressure). However, when the pressure was increased to 35 MPa, cell growth and bioethanol production decreased, with minimal production after the 4 consecutive fermentation cycles. In general, the results of this work suggest that consecutive cycles of fermentation under sub-lethal pressure conditions (15 and 25 MPa) can stimulate adaptation to pressure and improve the bioethanol production capacity by S. cerevisiae; hence, this technology can be used to increase rates, yields and productivities of alcoholic fermentation.


Assuntos
Adaptação Fisiológica , Etanol/metabolismo , Pressão/efeitos adversos , Saccharomyces cerevisiae/fisiologia , Biocombustíveis , Biomassa , Fermentação , Cinética , Viabilidade Microbiana , Saccharomyces cerevisiae/crescimento & desenvolvimento , Açúcares/análise
15.
Artigo em Inglês | MEDLINE | ID: mdl-28798803

RESUMO

Andiroba (Carapa guianensis) seeds are the source of an oil with a wide range of biological activities and ethnopharmacological uses. However, few studies have devoted attention to innovative formulations, including nanoemulsions. The present study aimed to obtain a colloidal system with the andiroba oil using a low-energy and organic-solvent-free method. Moreover, the preliminary residual larvicidal activity of the nanoemulsion against Aedes aegypti was evaluated. Oleic and palmitic acids were the major fatty acids, in addition to the phytosterol ß-sitosterol and limonoids (tetranortriterpenoids). The required hydrophile-lipophile was around 11.0 and the optimal nanoemulsion was obtained using polysorbate 85. The particle size distribution suggested the presence of small droplets (mean diameter around 150 nm) and low polydispersity index (around 0.150). The effect of temperature on particle size distribution revealed that no major droplet size increase occurred. The preliminary residual larvicidal assay suggested that the mortality increased as a function of time. The present study allowed achievement of a potential bioactive oil in water nanoemulsion that may be a promising controlled release system. Moreover, the ecofriendly approach involved in the preparation associated with the great bioactive potential of C. guianensis makes this nanoemulsion very promising for valorization of this Amazon raw material.

16.
PLoS One ; 11(1): e0145835, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26742099

RESUMO

Pterodon emarginatus Vogel is a Brazilian species that belongs to the family Fabaceae, popularly known as sucupira. Its oil has several biological activities, including potent larvicidal property against Aedes aegypti. This insect is the vector of dengue, a tropical disease that has been considered a critical health problem in developing countries, such as Brazil. Most of dengue control methods involve larvicidal agents suspended or diluted in water and making active lipophilic natural products available is therefore considered a technological challenge. In this context, nanoemulsions appear as viable alternatives to solve this major problem. The present study describes the development of a novel nanoemulsion with larvicidal activity against A. aegypti along with the required Hydrophile Lipophile Balance determination of this oil. It was suggested that the mechanism of action might involve reversible inhibition of acetylcholinesterase and our results also suggest that the P. emarginatus nanoemulsion is not toxic for mammals. Thus, it contributes significantly to alternative integrative practices of dengue control, as well as to develop sucupira based nanoproducts for application in aqueous media.


Assuntos
Aedes/efeitos dos fármacos , Fabaceae/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Nanoestruturas/química , Óleos Voláteis/farmacologia , Acetilcolinesterase/metabolismo , Aedes/enzimologia , Aedes/crescimento & desenvolvimento , Animais , Comportamento Animal/efeitos dos fármacos , Dengue/prevenção & controle , Emulsões , Feminino , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Inseticidas/isolamento & purificação , Larva/enzimologia , Larva/crescimento & desenvolvimento , Dose Letal Mediana , Camundongos , Controle de Mosquitos/métodos , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química
17.
Rev. bras. farmacogn ; 29(6): 778-784, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1057844

RESUMO

ABSTRACT Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson, Verbenaceae, is considered a great source of a bioactive volatile oil. Due to the wide range of known chemotypes, its chemical analysis is very important. Among the several activities of this volatile oil, a potential larvicidal action against Culicidae species is highlighted. However, the low water miscibility of volatile oils limits their application in aqueous media. Oil in water nano-emulsions are in the spotlight of novelty to solve this main problem. Thus, the aim of the present study was to obtain this nanostructured system with L. alba volatile oil (citral chemotype) and evaluate its larvicidal activity against Aedes aegypti and Culex quinquefasciatus larvae. The major compounds were geranial (30.02%) and neral (25.26%). Low mean droplet size (117.0 ± 1.0 nm) and low polydispersity index (0.231 ± 0.004) were observed and no major changes were observed after seven days of storage. LC50 values against C. quinquefasciatus and A. aegypti third-instar larvae were respectively 38.22 and 31.02 ppm, while LC90 values were, respectively, 59.42 and 47.19 ppm. The present study makes use of a low energy, solvent-free and ecofriendly method with reduced costs. Thus, this paper contributes significantly to phyto-nanobiotechnology of larvicidal agents, opening perspectives for the utilization of L. alba volatile oil in integrated practices of vector control.

18.
PLoS One ; 8(2): e56579, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23468868

RESUMO

Whole genome protein-protein association networks are not random and their topological properties stem from genome evolution mechanisms. In fact, more connected, but less clustered proteins are related to genes that, in general, present more paralogs as compared to other genes, indicating frequent previous gene duplication episodes. On the other hand, genes related to conserved biological functions present few or no paralogs and yield proteins that are highly connected and clustered. These general network characteristics must have an evolutionary explanation. Considering data from STRING database, we present here experimental evidence that, more than not being scale free, protein degree distributions of organisms present an increased probability for high degree nodes. Furthermore, based on this experimental evidence, we propose a simulation model for genome evolution, where genes in a network are either acquired de novo using a preferential attachment rule, or duplicated with a probability that linearly grows with gene degree and decreases with its clustering coefficient. For the first time a model yields results that simultaneously describe different topological distributions. Also, this model correctly predicts that, to produce protein-protein association networks with number of links and number of nodes in the observed range for Eukaryotes, it is necessary 90% of gene duplication and 10% of de novo gene acquisition. This scenario implies a universal mechanism for genome evolution.


Assuntos
Células Eucarióticas/metabolismo , Evolução Molecular , Duplicação Gênica , Genoma , Algoritmos , Simulação por Computador , Bases de Dados Genéticas , Eucariotos/genética , Eucariotos/metabolismo , Redes Reguladoras de Genes , Modelos Genéticos , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas
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