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1.
Food Chem ; 441: 138254, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38194792

RESUMO

This paper aimed to investigate the optimization of Gryllus assimilis farming production by examining the effects of replacing soybean meal with rapeseed cake (25-100%) and supplementing it with rapeseed oil. The results reveal no adverse effects of soybean meal replacement on the feed conversion ratio and weight of the harvested crickets. However, incorporating larger quantities of rapeseed cake into the diet increased crude protein and decreased fat content. Moreover, the composition of fatty acids varied significantly, with increased levels of oleic acid and decreased levels of palmitic acid, while a high rapeseed cake content led to a decrease in the atherogenic and thrombogenic index values. The amino acid composition remained unaffected. In conclusion, the study demonstrates that rapeseed cake can serve as a viable substitute for soybean meal in the diet of Gryllus assimilis.


Assuntos
Brassica napus , Brassica rapa , Brassica napus/metabolismo , Ração Animal/análise , Brassica rapa/química , Dieta , Ácidos Graxos/metabolismo , Glycine max
2.
Foods ; 12(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37569101

RESUMO

Essential oils have gained attention as natural alternatives to chemical preservatives in food preservation. However, more information is needed regarding consumer acceptance of essential oils in actual food products. This study aimed to compare the effects of conventional preservatives, heat treatment, and essential oils derived from thyme, oregano, and lemongrass on the survival and growth of pathogenic Escherichia coli in vegetable sauces. The results demonstrated a gradual decrease in pathogen numbers over time, even in untreated samples. On the fifth day of storage, heat treatment, sodium chloride, and acidification using citric acid (pH 3.2) exhibited reductions of 4.4 to 5.3 log CFU/g compared to the untreated control. Among the essential oils tested, lemongrass essential oil at a concentration of 512 mg/kg demonstrated the most remarkable effectiveness, resulting in a reduction of 1.9 log CFU/g compared to the control. Fifteen days after treatment, the control samples exhibited a contamination rate of 6.2 log CFU/g, while E. coli numbers in treated samples with heat, sodium chloride, citric acid (pH 3.2), and lemongrass essential oil (512 mg/kg) were below the detection limits. Additionally, sensory evaluation was conducted to assess the acceptability of the treated samples. The findings provide valuable insights into the potential utilisation of essential oils as natural preservatives in vegetable sauces and their impact on consumer acceptance.

3.
Sci Total Environ ; 892: 164712, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37301381

RESUMO

Emerging contaminants and their pervasive presence in freshwater ecosystems have been widely documented, but less is known about their prevalence and the harm they cause in marine ecosystems, particularly in developing countries. This study provides data on the prevalence and risk posed by microplastics, plasticisers, pharmaceuticals and personal care products (PPCPs), and heavy metal(loid)s (HMs) along the Maharashtra coast of India. The sediment and coastal water samples were collected from 17 sampling stations, processed, and subjected to FTIR-ATR, ICP-MS, SEM-EDX, LC-MS/MS, and GC-MS for further analysis. Higher MPs abundance, combined with the pollution load index, indicates that the northern zone is a high-impact zone with pollution concerns. Plasticisers in extracted MPs and HMs adsorption on MPs surface from surrounding waters reveal their roles as a source and vector for contaminants, respectively. The mean concentration of metoprolol (53.7-306 ng L-1), tramadol (16.6-198 ng L-1), venlafaxine (24.6-234 ng L-1), and triclosan (211-433 ng L-1) in Maharashtra's coastal waters were several folds higher than in other water systems, raising major health concerns. The hazard quotient (HQ) scores revealed that >70 % of study sites pose a high to medium (1 > HQ > 0.1) ecological risk to fish, crustaceans and algae, indicating serious concern. Fish and crustaceans (35.3 % each) show a higher level of risk than algae (29.5 %). Metoprolol and venlafaxine could represent greater ecological risks than tramadol. Similarly, HQ suggests that bisphenol A has larger ecological risks than bisphenol S along the Maharashtra coast. To the best of our knowledge, this is the first in-depth investigation into emerging pollutants in Indian coastal regions. This information is crucial for better policy formulation and coastal management in India in general, and Maharashtra in particular.


Assuntos
Cosméticos , Metais Pesados , Tramadol , Poluentes Químicos da Água , Animais , Microplásticos/análise , Ecossistema , Água/análise , Plásticos/análise , Sedimentos Geológicos , Cromatografia Líquida , Metoprolol , Cloridrato de Venlafaxina , Poluentes Químicos da Água/análise , Índia , Espectrometria de Massas em Tandem , Metais Pesados/análise , Medição de Risco , Cosméticos/análise , Preparações Farmacêuticas , Monitoramento Ambiental
4.
Antioxidants (Basel) ; 11(8)2022 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-36009288

RESUMO

Within the group of higher fungi, edible medicinal mushrooms have a long history of being used as food and in folk medicine. These species contain biologically active substances with many potential beneficial effects on human health. The Pleurotus genus is representative of medicinal mushrooms because Pleurotus ostreatus is one of the most commonly cultivated culinary mushrooms. In our study, we focused on lesser-known species in the genus Pleurotus and measured their antioxidant and anti-inflammatory activity. We prepared extracts of the mushrooms and analyzed them using HPLC-HRMS, GC-MS, and 1H-NMR. Significant differences in biological activities were found among the Pleurotus spp. extracts. A MeOH extract of P. flabellatus was the most active as a radical scavenger with the highest ORAC, while a chloroform extract had significant anti-inflammatory COX-2 activity. The 80% MeOH extract of P. flabellatus contained the highest amounts of ergosterol, ergothioneine, and mannitol. The 80% MeOH extract of P. ostreatus Florida was the most active in the NF-κB inhibition assay and had the highest content of ß-glucans (43.3% by dry weight). Given the antioxidant and anti-inflammatory properties of P. flabellatus, the potential therapeutic usefulness of this species is worth evaluating through in-depth investigations and confirmation by clinical trials.

5.
Chem Biol Interact ; 353: 109800, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34995571

RESUMO

Cannabis (Cannabis sativa L.) for medical purposes has been legalized again in many countries in recent years. Currently, only two major cannabinoids (Δ9-THC and CBD) are considered in the legislation and medication, which is not sufficient in case of dried plant material or resulting extract. Other substances (mainly terpenes/terpenoids), or their specific combinations, could influence the resulting therapeutic effect for specific oncology diagnosis and specific patients. Six different genotypes (Conspiracy Kush, Jilly Bean, Jack Cleaner 2, Jack Skellington, Nordle and Nurse Jackie) were cultivated indoor at the Czech University of Life Sciences Prague. Ethanol extracts taken from the inflorescences were assayed for their content of main cannabinoids and terpenes/terpenoids. The extracts were used for in vitro cytotoxicity studies on hepatocarcinoma human cell lines Hep-G2 and colorectal carcinoma human cell lines Caco-2 and Ht-29. Healthy lung fibroblast MRC-5 and healthy intestinal cells FHs 74 Int were used to compare selectivity of cytotoxicity. The average content of Δ9-THC in extracts was 59.1 ± 2.43%, and of CBD 1.84 ± 0.17%. The content of main cannabinoids in the Nurse Jackie genotype extract was significantly greater than that of the other genotypes. Overall, more than 60 different terpenes/terpenoids were identified in the extracts. The major terpenes/terpenoids detected in most genotypes were limonene, linalool, α-terpineol, ß-caryophyllene, trans-α-bergamotene, α-humulene, ß-caryophyllene oxide, guaiol, γ-eudesmol, ß-eudesmol and α-bisabolol. Differences in the terpene composition of individual genotypes were caused by minor terpenoids, such as ß-ocimene, isopulegol acetate, ß-elemene, ß-selinene and spathulenol. All extracts were highly cytotoxic to Ht-29 colorectal carcinoma cells and showed positive selectivity compared to healthy FHs 74 Int colon cells. The Jack Cleaner 2 extract was cytotoxic to all cell lines tested at the lowest concentrations (8.48 ± 2.4-16.14 ± 0,07 µg/mL), but was positively selective only for colorectal cancer cells, especially Ht-29 and to a lesser extent for Caco-2. Similarly, the Nordle extract showed positive selectivity for Ht-29 and Caco-2 only. Jilly Bean was unique in this study, in that its extract functioned on all cell lines at the highest concentrations (20.13 ± 3.05-49.88 ± 1.5 µg/mL), whilst also being highly positively selective in all carcinoma lines (Ht-29, Caco-2 and Hep-G2 hepatocarcinoma) compared to healthy cell lines (FHs 74 Int and MRC-5). The results suggest that Δ9-THC and CBD are responsible for the in vitro cytotoxicity of the extracts, but observed differences in selectivity reveal their synergies with other substances. According to chemical analysis, higher concentrations of myrcene, ß-elemene, ß-selinene and α-bisabolol oxide found in the Jilly Bean genotype may positively affect the selectivity of cytotoxic activity. It is therefore vital that similar studies are performed on other cell lines, in order to be able to recommend these cannabis genotypes for preclinical and clinical studies, which are still lacking.


Assuntos
Canabinoides/química , Cannabis/química , Extratos Vegetais/química , Terpenos/química , Canabinoides/análise , Cannabis/genética , Cannabis/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Etanol/química , Cromatografia Gasosa-Espectrometria de Massas , Genótipo , Humanos , Extratos Vegetais/farmacologia , Terpenos/análise , Terpenos/farmacologia
6.
Biomacromolecules ; 23(1): 276-290, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-34928129

RESUMO

The complexity of drug delivery mechanisms calls for the development of new transport system designs. Here, we report a robust synthetic procedure toward stable glycodendrimer (glyco-DDM) series bearing glucose, galactose, and oligo(ethylene glycol)-modified galactose peripheral units. In vitro cytotoxicity assays showed exceptional biocompatibility of the glyco-DDMs. To demonstrate applicability in drug delivery, the anticancer agent doxorubicin (DOX) was encapsulated in the glyco-DDM structure. The anticancer activity of the resulting glyco-DDM/DOX complexes was evaluated on the noncancerous (BJ) and cancerous (MCF-7 and A2780) cell lines, revealing their promising generation- and concentration-dependent effect. The glyco-DDM/DOX complexes show gradual and pH-dependent DOX release profiles. Fluorescence spectra elucidated the encapsulation process. Confocal fluorescence microscopy demonstrated preferential cancer cell internalization of the glyco-DDM/DOX complexes. The conclusions were supported by computer modeling. Overall, our results are consistent with the assumption that novel glyco-DDMs and their drug complexes are very promising in drug delivery and related applications.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Humanos , Polietilenoglicóis/química , Silanos
7.
Foods ; 10(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34945545

RESUMO

The main objective of this study is to evaluate the effect of selected essential oils thyme chemotype linalool (Thymus zygis L.), thyme chemotype tymol (Thymus vulgaris L.), eucalyptus (Eucalyptus globulus Labill.), lavender (Lavandula angustifolia Mill.), mint (Mentha piperita L.), almond (Prunbus dulcis Mill.), cinnamon bark (Cinnamomum zeylanicum Nees), litsea (Litsea cubeba Lour. Pers), lemongrass (Cympogon citrati L. Stapf), and ginger (Zingiber officinalis Rosc.) in the vapor phase on growth, sporulation, and mycotoxins production of two Aspergillus strains (Aspergillus parasiticus CGC34 and Aspergillus ochraceus CGC87), important postharvest pathogens of green and roasted coffee beans. Moreover, the effect of the essential oils (EOs) on the sensory profile of the coffee samples treated with EOs was evaluated. The major components of tested EOs were determined by gas chromatography and mass spectrometry (GC-MS) and gas chromatography with flame ionization detector (GC-FID). The results showed that almond, cinnamon bark, lemongrass, and litsea EOs are able to significantly inhibit the growth, sporulation, and mycotoxins production by toxigenic fungi. Sensory evaluation of coffee beans treated with EOs before and after roasting showed that some EOs (except lemongrass and litsea) do not adversely affect the taste and aroma of coffee beverages. Thus, application of the vapors of almond and cinnamon EOs appears to be an effective way that could serve to protect coffee during its transport and storage from toxigenic fungi.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34705616

RESUMO

The study aimed to assess the antifungal activity of twenty-five essential oils (EOs) and the potential synergistic activity of the most effective EOs against significant indoor fungi of the genus Aspergillus [A. fumigatus (KBio-122), A. flavus (KBio-134), A. terreus (KBio-145) and A. niger (KBio-202)]. The chemical composition of all EOs was evaluated by the gas chromatography coupled with mass spectrometry (GC/MS) and gas chromatography with flame ionization detector (GC-FID) analysis. The antifungal susceptibility of EOs was evaluated by using the broth microdilution method. The most effective EOs were selected to determine the minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) at a concentration range from 256 to 0.125 µg/mL. For the synergistic activities, the most effective EOs were tested using the chessboard pattern. The most sensitive strain to treatments with essential oils alone and in the combination of EOs was A. flavus (KBio-134). The chessboard assay showed that combinations of lemongrass and thyme EOs proved the most potent synergistic antifungal activity (FICI = 0.1875) against A. fumigatus (KBio-122). The synergy displayed by a combination of some EOs may be used to control fungal growth or increasing resistance to available synthetic antifungals, consequently permitting the reduction of their most active doses.


Assuntos
Óleos Voláteis , Antifúngicos/farmacologia , Aspergillus , Fungos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia
9.
PeerJ ; 9: e11662, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34322319

RESUMO

The number of described species of the oomycete genus Phytophthora is growing rapidly, highlighting the need for low-cost, rapid tools for species identification. Here, a collection of 24 Phytophthora species (42 samples) from natural as well as anthropogenic habitats were genetically identified using the internal transcribed spacer (ITS) and cytochrome c oxidase subunit I (COI) regions. Because genetic identification is time consuming, we have created a complementary method based on by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Both methods were compared and hypothesis that the MALDI-TOF MS method can be a fast and reliable method for the identification of oomycetes was confirmed. Over 3500 mass spectra were acquired, manually reviewed for quality control, and consolidated into a single reference library using the Bruker MALDI Biotyper platform. Finally, a database containing 144 main spectra (MSPs) was created and published in repository. The method presented in this study will facilitate the use of MALDI-TOF MS as a complement to existing approaches for fast, reliable identification of Phytophthora isolates.

10.
Nanomaterials (Basel) ; 11(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068155

RESUMO

Essential oil components (EOCs) such as eugenol play a significant role in plant antimicrobial defense. Due to the volatility and general reactivity of these molecules, plants have evolved smart systems for their storage and release, which are key prerequisites for their efficient use. In this study, biomimetic systems for the controlled release of eugenol, inspired by natural plant defense mechanisms, were prepared and their antifungal activity is described. Delivery and antifungal studies of mesoporous silica nanoparticles (MSN) loaded with eugenol and capped with different saccharide gates-starch, maltodextrin, maltose and glucose-against fungus Aspergillus niger-were performed. The maltodextrin- and maltose-capped systems show very low eugenol release in the absence of the fungus Aspergillus niger but high cargo delivery in its presence. The anchored saccharides are degraded by exogenous enzymes, resulting in eugenol release and efficient inhibition of fungal growth.

11.
Molecules ; 26(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804452

RESUMO

Fungal contamination in stored food grains is a global concern and affects food economics and human and animal health. It is clear that there is a need to develop new technologies with improved performances that are also eco-friendly in nature. Due to the bioactivity of essential oils (EOs) in the vapor phase, their low toxicity for humans, and their biodegradability and antifungal properties, EOs could be a suitable solution. In this study, we explored the potential of thyme, oregano, lemongrass, clove, and cajeput EOs in the vapor phase. For 17 days, inhibitory activity was assessed against five strains of postharvest pathogens-Aspergillus spp., Fusarium s. l. spp., and Penicilliumochrochloron-isolated from cereal grains. A modified disc volatilization method was used, which is more effective in comparison to traditional screening methods. Three concentrations were tested (250, 125, and 62.5 µL/L). The two highest concentrations resulted in complete inhibition of fungal growth; however, even 62.5 µL/L showed a significant antifungal effect. The efficiency of EOs followed this order: thyme > oregano > lemongrass > clove > cajeput. From our findings, it appears that the use of EOs vapors is a better option not only for laboratory experiments, but for subsequent practice.


Assuntos
Antifúngicos/farmacologia , Grão Comestível/química , Fungos/crescimento & desenvolvimento , Óleos Voláteis/farmacologia , Fungos/efeitos dos fármacos , Fungos/isolamento & purificação
12.
Food Chem ; 328: 127131, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32485586

RESUMO

Carvacrol (CAR) is a natural bioactive compound with antioxidant and antimicrobial activity that is present in essential oils. The application of CAR in food preservation is hampered by its high volatility, low solubility in water, and susceptibility to light, heat and oxygen degradation. Polylactide (PLA) is an FDA-approved polymer derived from renewable resources. Controlled release of CAR from PLA nanoparticles (NPs) could improve its antimicrobial efficacy and storage. In this study, negatively charged CAR-NPs and positively charged polyethylenimine (PEI)-coated CAR-(PEI)NPs were formulated by nanoprecipitation methods and characterised by dynamic light scattering, electron microscopy, encapsulation efficiency, and drug loading capacity. The positively charged (PEI)NPs enhanced the in vitro antimicrobial activity of CAR against Escherichia coli, Listeria monocytogenes, Salmonella enterica and Staphylococcus aureus. Bacterial uptake, evaporation tests, release studies and NP stability after storage were assessed to provide evidence supporting CAR-(PEI)NPs as a potential nanocarrier for further development in food preservation.


Assuntos
Antibacterianos/farmacologia , Cimenos/farmacologia , Nanopartículas/química , Poliésteres/química , Antibacterianos/química , Cimenos/química , Cimenos/farmacocinética , Portadores de Fármacos/química , Escherichia coli/efeitos dos fármacos , Microbiologia de Alimentos , Listeria monocytogenes , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Polietilenoimina/química , Salmonella enterica/efeitos dos fármacos , Solubilidade , Staphylococcus aureus/efeitos dos fármacos
13.
J Econ Entomol ; 113(1): 255-262, 2020 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-31687745

RESUMO

The Colorado potato beetle ranks as one of the most important potato pests, mainly due to its high feeding rate during all developmental stages, particularly third and fourth larval instar, and high fecundity. The effect of essential oil (EO) from anise (Pimpinella anisum L. [Apiales: Apiaceae]) prepared as conventional and encapsulated (EN) formulations on the mortality and antifeedant responses of young larvae of Colorado potato beetles was studied to evaluate the insecticidal and antifeedant effects of five concentrations of this EO and to assess the persistence of both formulations on potato plants. The EN formulation had a significantly higher residual amount compared with that of the conventionally formulated EO. Significantly different values of LC50 and LC90 (ppm) were established for the EO (LC50 = 1,700 and LC90 = 9500) and EN (LC50 = 3,100 and LC90 = 14,300) formulations. The effects of both P. anisum formulations (EO and EN) applied topically to Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae) larvae were distinctly different from those observed with the contact treatment. At the highest concentration of 20,000 ppm, the mortality of the second instars of the L. decemlineata larvae did not exceed 25%. On the other hand, both tested formulations of P. anisum were highly effective when administered orally. The encapsulated EO formulation achieved a distinctly higher biological activity. Our results confirm that the EO from P. anisum, especially the encapsulated formulation, has high insecticidal properties that may lead to the development of new organic products for the control of Colorado potato beetles.


Assuntos
Besouros , Óleos Voláteis , Pimpinella , Solanum tuberosum , Animais , Colorado , Larva
14.
Food Chem ; 272: 267-272, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309543

RESUMO

Since January 2018, insects have been recognised as novel foods in the EU, but their nutritional value varies, and factors affecting their nutritional composition have been debated. We investigated the effect of sex on the nutritional value and chemical composition of the house cricket (Acheta domestica L.). Both sexes were rich in protein and lipids. The proximate composition was partly influenced by sex; females contained a significantly higher amount of lipids (18.3-21.7 vs 12.9-16.1 g/100 g dry matter, p = 0.0001) and fewer proteins than males (61.2-64.9 vs 66.3-69.6 g/100 g dry matter, p = 0.0001). Males contained more chitin (p = 0.0015) and nitrogen chains (p = 0.0003) than females. Only the ash (p = 0.4314) and nitrogen-free extract (p = 0.4871) were uninfluenced by sex. Furthermore, nutrient quality expressed as essential amino acid (72.3-77.1), thrombogenicity (1.22-1.45), and atherogenicity indices (0.53-0.58) did not differ between sexes (p > 0.05).


Assuntos
Gryllidae/química , Valor Nutritivo , Animais , Feminino , Proteínas de Insetos/análise , Lipídeos/análise , Masculino , Fatores Sexuais
15.
Data Brief ; 21: 962-965, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30426052

RESUMO

In this dataset we provide MALDI-TOF MS spectra of Escherichia coli. The data presented in this article are related to the article entitled "Stress response of Escherichia coli to essential oil components - insights on low-molecular-weight proteins from MALDI-TOF" (Bozik et al., 2018) [1]. Essential oils and their components are known for their antibacterial effect. Many studies evaluated the effect of essential oil components (EOCs) on the cell wall, bacterial membranes, and energetic metabolism. But data about low molecular weight proteins (<20 kDa) are limited. Provided data are focused on bacterial response to EOCs; tetracycline, peroxide and chlorine was used as control as common antibiotic and disinfectant agents used against bacteria. These data describe the effect of tested substances to bacterial protein synthesis.

16.
Sci Rep ; 8(1): 13042, 2018 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158663

RESUMO

The antibacterial effects of essential oils and their components (EOCs) are usually attributed to effects on membranes and metabolism. Studies of the effects of EOCs on protein expression have primarily analysed proteins larger than 10 kDa using gel electrophoresis. In the present study, we used MALDI-TOF-MS to investigate the effects of EOCs on low-molecular-weight proteins. From 297 m/z features, we identified 94 proteins with important differences in expression among untreated samples, samples treated with EOCs, and samples treated with antibiotics, peroxide, or chlorine. The targets of these treatments obviously differ, even among EOCs. In addition to ribosomal proteins, stress-, membrane- and biofilm-related proteins were affected. These findings may provide a basis for identifying new targets of essential oils and synergies with other antibiotics.


Assuntos
Antibacterianos/metabolismo , Proteínas de Escherichia coli/análise , Escherichia coli/efeitos dos fármacos , Óleos Voláteis/metabolismo , Proteoma/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estresse Fisiológico , Escherichia coli/fisiologia , Proteínas de Escherichia coli/química , Peso Molecular
17.
Artigo em Inglês | MEDLINE | ID: mdl-29842823

RESUMO

The main objective of this study was using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for assembling of DSM (German Collection of Microorganisms) Streptomyces spectral database and identification of wild Streptomyces cultures, which were clustered by MALDI-TOF Biotyper OC software as well as for teracycline detection by observing of obtained spectra using flexAnalysis software. Production of tetracycline was confirmed by thin-layer chromatography. Presence of tetracycline mass spectrum was verified by several tetracycline producers (Streptomyces aureofaciens LMG 5968, S. aureofaciens 84/25, and S. aureofaciens BMK) and by pure tetracycline mass. Our results showed that it is possible to use MALDI-TOF MS for identification of tetracycline producers within Streptomyces genera by several easy steps. The purpose of this study was to establish cheap and quick detection of tetracycline producers.


Assuntos
Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Streptomyces/isolamento & purificação , Streptomyces/metabolismo , Tetraciclina/metabolismo , Bases de Dados Factuais , Ensaios de Triagem em Larga Escala/métodos , Humanos , Software , Tetraciclina/química , Tetraciclina/isolamento & purificação
18.
Folia Microbiol (Praha) ; 57(4): 273-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22528302

RESUMO

Fecal bacteria from 33 infants (aged 1 to 6 months) were tested for growth on commercial prebiotics. The children were born vaginally (20) or by caesarean section (13). Bifidobacteria, lactobacilli, gram-negative bacteria, Escherichia coli, and total anaerobes in fecal samples were enumerated by selective agars and fluorescence in situ hybridization. The total fecal bacteria were inoculated into cultivation media containing 2 % Vivinal® (galactooligosaccharides-GOS) or Raftilose® P95 (fructooligosaccharides-FOS) as a single carbon source and bacteria were enumerated again after 24 h of anaerobic cultivation. Bifidobacteria dominated, reaching counts of 9-10 log colony-forming units (CFU)/g in 17 children born vaginally and in seven children delivered by caesarean section. In these infants, lactobacilli were more frequently detected and a lower number of E. coli and gram-negative bacteria were determined compared to bifidobacteria-negative infants. Clostridia dominated in children without bifidobacteria, reaching counts from 7 to 9 log CFU/g. Both prebiotics supported all groups of bacteria tested. In children with naturally high counts of bifidobacteria, bifidobacteria dominated also after cultivation on prebiotics, reaching counts from 8.23 to 8.77 log CFU/mL. In bifidobacteria-negative samples, clostridia were supported by prebiotics, reaching counts from 7.17 to 7.69 log CFU/mL. There were no significant differences between bacterial growth on Vivinal® and Raftilose® P95 and counts determined by cultivation and FISH. Prebiotics should selectively stimulate the growth of desirable bacteria such as bifidobacteria and lactobacilli. However, our results showed that commercially available FOS and GOS may stimulate also other fecal bacteria.


Assuntos
Bactérias/crescimento & desenvolvimento , Fezes/microbiologia , Prebióticos/análise , Bactérias/isolamento & purificação , Feminino , Humanos , Lactente , Masculino
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