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1.
J Fungi (Basel) ; 10(3)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38535233

RESUMO

The mushroom industry should implement green extraction technologies; however, there is not enough information on the differences between these techniques expressed as the chemical composition of the resulting extract. In this study, selected types of green extraction techniques (GETs) were used on Chaga (Inonotus obliquus) (Fr.) Pilát from Serbia (IS) and Mongolia (IM) to examine the differences that would enable the composition-based technology choices in the mushroom supplement industry. Subcritical water extraction (SWE), microwave-assisted (MW) extraction, and ultrasonic-assisted extraction (VAE) were used to prepare the extracts. SWE was performed at two different temperatures (120 and 200 °C), while 96% ethanol, 50% ethanol, and water were used for MW and VAE. The yield, the content of total phenols, total proteins, and carbohydrates, qualitative and quantitative analysis of phenolic compounds, carbohydrates, including α- and ß- and total glucans, and fatty acids, were determined in the obtained extracts. SWE resulted in a significantly higher yield, total polysaccharide, and glucan content than any other technique. Glucose was the most dominant monosaccharide in the SWE samples, especially those extracted at 200 °C. The MW 50% EtOH extracts showed the highest yield of total phenols. Among the tested phenolic compounds, chlorogenic acid was the most dominant. SWE can be recommended as the most efficient method for extracting commercially important compounds, especially glucans and phenols.

2.
Molecules ; 29(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38257227

RESUMO

Growing mushrooms means meeting challenges while aiming for sustainability and circularity. Wherever the producer is located, commercial strains are the same originating from several producers. Customized strains adapted to local conditions are urgently needed. Before introducing new species to the strain development pipeline, the chemical characterization and biological activity of wild ones need to be assessed. Accordingly, the mycoceutical potential of five polypore mushroom species from Serbia was evaluated including: secondary metabolite composition, oxidative damage prevention, anti-tyrosinase, and anti-angiotensin converting enzyme (ACE). The phenolic pattern was comparable in all samples, but the amounts of specific chemicals varied. Hydroxybenzoic acids were the primary components. All samples had varying quantities of ascorbic acid, carotene, and lycopene, and showed a pronounced inhibition of lipid peroxidation (LPx) and ability to scavenge HO•. Extracts were more potent tyrosinase inhibitors but unsuccessful when faced with ACE. Fomitopsis pinicola had the strongest anti-tumor efficacy while Ganoderma lucidum demonstrated strong selectivity in anti-tumor effect in comparison to normal cells. The evaluated species provided a solid foundation for commercial development while keeping local ecology in mind.


Assuntos
Agaricales , Bioprospecção , Península Balcânica , Ácido Ascórbico , Monofenol Mono-Oxigenase
3.
Chem Biodivers ; 20(11): e202301044, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37772689

RESUMO

The composition and anticholinesterase activity of the dried MeOH extracts of Hieracium scheppigianum and H. naegelianum underground parts (rhizomes and roots), as well as the anticholinesterase activity of the dried, previously chemically characterised MeOH extracts of the flowering aerial parts of these two and 26 other Hieracium species in the strict sense (s. str.), were investigated. Furthermore, the anticholinesterase activity of 12 selected secondary metabolites of these extracts was evaluated. Using semi-preparative LC-MS, five caffeoylquinic acids and the sesquiterpene lactone crepiside E were isolated from H. scheppigianum underground parts extract. All these compounds were also identified in the underground parts extract of H. naegelianum. Quantitative LC-MS analysis showed that the analysed underground parts extracts were rich in both caffeoylquinic acids (139.77 and 156.62 mg/g of extract, respectively) and crepiside E (126.88 and 116.58 mg/g). In the Ellman method, the tested extracts showed an interesting anti-AChE and/or anti-BChE activity (IC50 =0.56-1.58 mg/mL), which can be explained, at least partially, by the presence of some of their constituents. Among the metabolites tested, the best activity was revealed for the flavonoids apigenin, luteolin and diosmetin, and the sesquiterpene lactone 8-epiixerisamine A (IC50 =68.09-299.37 µM).


Assuntos
Asteraceae , Sesquiterpenos , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Metanol/química , Antioxidantes/química , Extratos Vegetais/química , Componentes Aéreos da Planta/química , Flavonoides/análise , Asteraceae/química , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos/análise
4.
Antibiotics (Basel) ; 12(3)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36978494

RESUMO

The problem of microbial biofilms has come to the fore alongside food, pharmaceutical, and healthcare industrialization. The development of new antibiofilm products has become urgent, but it includes bioprospecting and is time and money-consuming. Contemporary efforts are directed at the pursuit of effective compounds of natural origin, also known as "green" agents. Mushrooms appear to be a possible new source of antibiofilm compounds, as has been demonstrated recently. The existing modeling methods are directed toward predicting bacterial biofilm formation, not in the presence of antibiofilm materials. Moreover, the modeling is almost exclusively targeted at biofilms in healthcare, while modeling related to the food industry remains under-researched. The present study applied an Artificial Neural Network (ANN) model to analyze the anti-adhesion and anti-biofilm-forming effects of 40 extracts from 20 mushroom species against two very important food-borne bacterial species for food and food-related industries-Listeria monocytogenes and Salmonella enteritidis. The models developed in this study exhibited high prediction quality, as indicated by high r2 values during the training cycle. The best fit between the modeled and measured values was observed for the inhibition of adhesion. This study provides a valuable contribution to the field, supporting industrial settings during the initial stage of biofilm formation, when these communities are the most vulnerable, and promoting innovative and improved safety management.

5.
Mutagenesis ; 38(1): 71-80, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35253882

RESUMO

Ultraviolet (UV) radiation can result in DNA damage, mainly through direct formation of pyrimidine dimers and generation of reactive oxygen species, which can lead to the skin disorders including cancer. In accordance with this, the use of natural antigenotoxins and/or antioxidants could contribute to human health protection. Considering that plants are rich in both, the aim of this study was to investigate UV-protective and antioxidative properties of yellow gentian (Gentiana lutea), being well established in pharmacopeias and traditional medicine. Tested extracts were derived from root and shoot of the in vitro cultivated plants. Prescreening of the genotoxic properties of UVC, UVA, and the extracts, as well as the extracts' antigenotoxicity were estimated by applying alkaline comet assay on normal fetal lung fibroblast (MRC-5) and human melanoma cells (Hs 294T). Antioxidant potential was tested in ferrous ions chelating ferric reducing antioxidant power and cupric reducing antioxidant capacity assays. Genotoxicity testing, which revealed moderate DNA-damaging potential of root extract on MRC-5 cells and high genotoxicity of shoot extract on both cell lines, pointed out nongenotoxic concentrations that could be used in antigenotoxicity assay. Doses of 63 and 3 J/cm2 for UVC and UVA, respectively, were established for antigenotoxicity study, since they induced sufficient DNA damage without notable cytotoxicity. Results of antigenotoxicity revealed strong protective effect of both extracts against UVC (the highest inhibitions 58% and 47%) and UVA (the highest inhibitions 69% and 60%), in Hs 294T and MRC-5 cells, respectively. Study of the antioxidative properties demonstrated stronger activity of shoot extract. Results obtained proved to be encouraging but further research of the UV-protective role of Gentiana lutea extracts and underlying molecular mechanisms is recommended.


Assuntos
Antioxidantes , Gentiana , Humanos , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Dano ao DNA , Ensaio Cometa , Raios Ultravioleta/efeitos adversos
7.
World J Microbiol Biotechnol ; 37(1): 17, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33394203

RESUMO

Four types of mycelial extracts were derived from the airlift liquid fermentation (ALF) of Pleurotus flabellatus, namely exopolysaccharide (EX), endopolysaccharide (EN), hot water (WE), and hot alkali (AE) extracts. Such extracts were screened for their active components and biological potential. EN proved to be most effective in inhibition of lipid peroxidation (EC50 = 1.71 ± 0.02 mg/mL) and in Cupric ion reducing antioxidant capacity (CUPRAC) assay (EC50 = 2.91 ± 0.01 mg TE/g). AE exhibited most pronounced ability to chelate ferrous ions (EC50 = 4.96 ± 0.08 mg/mL) and to scavenge ABTS radicals (EC50 = 3.36 ± 0.03 mg TE/g). ß-glucans and total phenols contributed most to the chelating ability and quenching of ABTS radicals. Inhibition of lipid peroxidation correlated best with total glucans, total proteins, and ß-glucans. Total proteins contributed most to CUPRAC antioxidant capacity. Antifungal effect was determined against Candida albicans ATCC 10231 (MIC: 0.019-0.625 mg/mL; MFC: 0.039-2.5 mg/mL), and towards C. albicans clinical isolate (MIC and MFC: 10.0-20.0 mg/mL). Comparison of cytotoxicity against colorectal carcinoma HCT 116 cells (IC50: 1.8 ± 0.3-24.6 ± 4.2 mg/mL) and normal lung MRC-5 fibroblasts (IC50: 17.0 ± 4.2-42.1 ± 6.1 mg/mL) showed that EN, and especially AE possess selective anticancer activity (SI values 3.41 and 9.44, respectively). Slight genotoxicity was observed only for AE and EX, indicating the low risk concerning this feature. Notable antioxidative and anticandidal activities, selective cytotoxicity against colorectal carcinoma cells, and absence/low genotoxicity pointed out that ALF-cultivated P. flabellatus mycelium could be considered as a valuable source of bioactive substances.


Assuntos
Antifúngicos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Fatores Biológicos/isolamento & purificação , Reatores Biológicos/microbiologia , Pleurotus/crescimento & desenvolvimento , Antifúngicos/química , Antifúngicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Fatores Biológicos/química , Fatores Biológicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fermentação , Polissacarídeos Fúngicos/isolamento & purificação , Polissacarídeos Fúngicos/farmacologia , Células HCT116 , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pleurotus/química , beta-Glucanas/isolamento & purificação , beta-Glucanas/farmacologia
8.
Bioorg Chem ; 102: 104073, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32693308

RESUMO

In this study we synthesized a series of sixteen bis(imino)pyridines (BIPs) starting from 2,6-diaminopyridine and various aromatic aldehydes, and evaluated their antioxidant, antibacterial, antifungal and acetylcholinesterase (AChE) inhibitory activity. The chemical structures were elucidated by FTIR, elemental analysis, ESR and HRMS. 1H and 13C NMR spectra couldn't be acquired due to the formation of stable, carbon-centered radical cations in a solution, as confirmed by ESR spectroscopy and DFT calculations. The in vitro antioxidant potency was evaluated using four assays: free radical scavenging activity (DPPH and ABTS), reducing power and total antioxidant capacity assay. BIPs demonstrated excellent antioxidant properties, and two derivatives proved to be more potent than reference antioxidants (ascorbic acid and Trolox) in all assays. DFT calculations on ωB97XD/6-311++g(d,p) level of theory provided valuable insights into the radical scavenging mechanism of BIPs. For hydroxyl-substituted BIPs, hydrogen atom transfer (HAT) is a predominant mechanism, while the single electron transfer coupled with proton transfer (SET-PT) governs the antioxidant activity of other derivatives. Intramolecular hydrogen bonding (IHB) plays an important role in the mechanism of antioxidant activity as revealed by noncovalent interaction analysis and rotational barrier calculations. The spin density of radical cations is localized on carbon atoms of a pyridine ring, which corroborates with g-factors and multiplicity obtained from ESR analysis. The most potent BIP exhibited moderate inhibitory activity toward AChE (IC50 = 20 ± 4 µM), while molecular docking suggested binding at the peripheral anionic site of AChE with the MMFF94 binding enthalpy of -43.4 kcal/mol. Moderate in vitro antimicrobial activity of BIPs have been determined against several pathogenic bacterial strains: Pseudomonas aeruginosa, Escherichia coli, Enterococcus faecalis, Staphylococcus aureus and clinical isolate of methicillin resistant S. aureus (MRSA). The antifungal activity of BIPs toward Candida albicans was also confirmed. The similarity ensemble approach combined with molecular docking suggested leucyl aminopeptidase as the probable antimicrobial target for the three most potent BIP derivatives.


Assuntos
Anti-Infecciosos/uso terapêutico , Antifúngicos/uso terapêutico , Antioxidantes/uso terapêutico , Inibidores da Colinesterase/uso terapêutico , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Piridinas/síntese química , Piridinas/uso terapêutico , Candida albicans , Humanos , Piridinas/farmacologia , Relação Estrutura-Atividade
9.
Int J Med Mushrooms ; 22(9): 869-883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33389853

RESUMO

Crude polysaccharide extracts derived from Agaricus bisporus (A), A. brasiliensis (B), and Phellinus linteus (P) were used for the synthesis of silver nanoparticles (AgNPs, labeled AAgNP, BAgNP, PAgNP, respectively). UV and FT-IR spectra, size distribution, and zeta potential of the respective particles were recorded, and TEM and SEM-EDS characterization was done. UV-Vis spectroscopy showed maximum absorbance at 415 nm for A, at 400 nm for P, and at 420 nm for B. SEM-EDS analysis showed BAgNP to consist of almost 90% of silver, while silver content in AAgNP and PAgNP was much lower, 46.5 and 52.3%, respectively. Individual extracts as well as the Ag-NPs were tested against a panel of clinically isolated and ATCC derived pathogens. In almost all cases minimum inhibitory concentration (MIC) was significantly lower than those of antibiotics, suggesting up to 100 times more effectivity. BAgNP, PAgNP, and AAgNP appeared very active against Pseudomonas aeruginosa ATCC 27853 (MIC: 0.19, 0.19, 0.97 µg/mL, respectively). The same nanoparticles were also very effective toward Candida albicans ATCC 10231 (MIC: 0.39, 0.78, 0.97 µg/mL, respectively). Our study indicates that the bactericidal effect of PAgNP, AAgNP, BAgNP on E. coli 25922 ATCC (MBC: 1.56, 0.97, 6.25 µg/mL, respectively) is significantly more pronounced than that of amoxicillin. A pure solution of colloidal silver nanoparticles showed significantly weaker microbiostatic/microbiocidal potential than all tested mushroom extracts' AgNPs, as well as amoxicillin. Silver nanoparticles made with extracts of A, B, and P seem welcome as an addition to the inventory of antimicrobial compounds used in clinical medicine against bacterial and yeast infection.


Assuntos
Agaricus/química , Anti-Infecciosos/química , Basidiomycota/química , Polissacarídeos Fúngicos/química , Nanopartículas Metálicas/química , Prata/química , Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Prata/farmacologia
10.
Foods ; 8(12)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816984

RESUMO

The antioxidant and antimicrobial properties of Cantharellus cibarius decoction and the effect of mushroom addition on the physicochemical and microbiological properties of frankfurters during refrigerated storage were studied. Mushroom addition significantly reduced (p < 0.05) the formation of total aerobic mesophilic bacteria during storage. Regarding the texture, there was no negative effect in frankfurters with the mushroom added, compared to the control group of sausages. Generally, C. cibarius can be used as a natural ingredient in order to prevent the growth of microorganisms in cooked pork sausages, causing an extension in shelf life during chilled storage.

11.
Sci Rep ; 9(1): 16109, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31695087

RESUMO

The fluctuation of domestic wastewater characteristic inhibits the current conventional microbial-based treatment. The bioremediation fungi has received attention and reported to be an effective alternative to treat industrial wastewater. Similar efficient performance is envisaged for domestic wastewater whereby assessed performance of fungi for varying carbon-to-nitrogen ratios in domestic wastewater is crucial. Thus, the performance of pre-grown wild-Serbian Ganoderma lucidum mycelial pellets (GLMPs) was evaluated on four different synthetic domestic wastewaters under different conditions of initial pH (pH 4, 5, and 7) and chemical oxygen demand (COD) to nitrogen (COD/N) ratio of 3.6:1, 7.1:1, 14.2:1, and 17.8:1 (C3.6N1, C7.1N1, C14.2N1, and C17.8N1). The COD/N ratios with a constant concentration of ammonia-nitrogen (NH3-N) were chosen on the basis of the urban domestic wastewater characteristics sampled at the inlet basin of a sewage treatment plant (STP). The parameters of pH, COD, and NH3-N were measured periodically during the experiment. The wild-Serbian GLMPs efficiently removed the pollutants from the synthetic sewage. The COD/N ratio of C17.8N1 wastewater had the best COD and NH3-N removal, as compared to the lower COD/N ratio, and the shortest treatment time was obtained in an acidic environment at pH 4. The highest percentage for COD and NH3-N removal achieved was 96.0% and 93.2%, respectively. The results proved that the mycelium of GLMP has high potential in treating domestic wastewater, particularly at high organic content as a naturally sustainable bioremediation system.


Assuntos
Micélio/metabolismo , Reishi/crescimento & desenvolvimento , Esgotos/microbiologia , Purificação da Água/métodos , Amônia/análise , Amônia/metabolismo , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Micélio/crescimento & desenvolvimento , Nitrogênio/análise , Nitrogênio/metabolismo , Oxigênio/análise , Oxigênio/metabolismo , Reishi/metabolismo , Esgotos/química , Purificação da Água/instrumentação
12.
AIMS Microbiol ; 5(1): 19-38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384700

RESUMO

Wild-cultivated medicinal mushroom Ganoderma lucidum was morphologically identified and sequenced using phylogenetic software. In submerged-liquid fermentation (SLF), biomass, exopolysaccharide (EPS) and intracellular polysaccharide (IPS) production of the identified G. lucidum was optimised based on initial pH, starting glucose concentration and agitation rate parameters using response surface methodology (RSM). Molecularly, the G. lucidum strain QRS 5120 generated 637 base pairs, which was commensurate with related Ganoderma species. In RSM, by applying central composite design (CCD), a polynomial model was fitted to the experimental data and was found to be significant in all parameters investigated. The strongest effect (p < 0.0001) was observed for initial pH for biomass, EPS and IPS production, while agitation showed a significant value (p < 0.005) for biomass. By applying the optimized conditions, the model was validated and generated 5.12 g/L of biomass (initial pH 4.01, 32.09 g/L of glucose and 102 rpm), 2.49 g/L EPS (initial pH 4, 24.25 g/L of glucose and 110 rpm) and 1.52 g/L of IPS (and initial pH 4, 40.43 g/L of glucose, 103 rpm) in 500 mL shake flask fermentation. The optimized parameters can be upscaled for efficient biomass, EPS and IPS production using G. lucidum.

13.
Food Sci Biotechnol ; 26(1): 159-165, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263523

RESUMO

Underutilized mycelium of Ganoderma lucidum BCCM 31549 has been a significant source of a glucan sulfate (GS) possessing therapeutic activities. GS have been evaluated for their antifungaldemelanizing properties and nitrite oxide production from stimulated RAW264.7 macrophages. GS exhibited antifungal activity against Aspergillus niger A60 with a minimum inhibitory concentration of 60 mg/mL and a minimum fungicidal concentration of 100 mg/mL. At 60mg/mL (sublethal) and 30mg/mL (subinhibitory) doses of GS, the mycelium of A. niger A60 was successfully demelanized with a conidiophore head and black pigment reduction. Additionally, GS successfully stimulated RAW264.7 macrophage cells at a concentration of 500 µg/mL to produce 0.45 µM of nitric oxide. The GS-stimulated RAW264.7 macrophages were morphologically similar to those treated with lipopolysaccharide. The results highlight a novel bifunctional property of mycelial GS from G. lucidum.

14.
J Sci Food Agric ; 97(9): 3013-3021, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27859282

RESUMO

BACKGROUND: The aim of this study was to develop a total quality index and examine the effects of modified atmosphere packaging (MAP) on the quality of Agaricus bisporus mushrooms stored for 22 days at 4 °C. Mushrooms were packaged under three MAPs: high nitrogen packaging (HNP), low carbon dioxide packaging (LCP) and low oxygen packaging (LOP). Passive MAP with air inside initially was used as the atmosphere treatment (AIR). RESULTS: This research revealed two phases in quality deterioration of A. bisporus mushrooms. During the first week, most of the quality parameters were not statistically different. Thereafter, odor intensities were stronger for all four types of packaging. Color difference and browning index values showed significantly lower color changes for AIR and LOP compared with HNP and LCP mushrooms. CONCLUSION: The best total quality index was calculated for LOP, followed by LCP and AIR. The findings of this study are useful with respect to examining two-component MAPs, separating the limiting factors (O2 and CO2 ) and evaluating quality deterioration effects and the total quality index of A. bisporus mushrooms. © 2016 Society of Chemical Industry.


Assuntos
Agaricus/química , Embalagem de Alimentos/métodos , Verduras/química , Embalagem de Alimentos/instrumentação , Oxigênio/análise , Controle de Qualidade , Temperatura
15.
Int J Med Mushrooms ; 18(9): 781-792, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27910770

RESUMO

Kaolinite and the modified natural zeolite minazel plus (M+) were used as supplements in substrate used for the production of the medicinal mushroom Grifola frondosa. Growth stimulation, expressed as yield and biological efficiency, was observed when M+ (1%) was added. The production cycle was shortened by half as a result of the zeolites' ion-exchange ability, stimulation of enzyme activity, and water retain capacity. Inductively coupled plasma optical emission spectrometry of fruiting bodies showed the absence of heavy metals (arsenic, cadmium, and lead), whereas the concentration of calcium increased greatly and the concentrations of iron, magnesium, and zinc increased moderately under the influence of M+. Solid-state nuclear magnetic resonance showed a positive impact on the ß-glucan ratio, which could have been caused by the epimerization reaction stimulated by zeolites. The functionality of the mushroom was evaluated through several antioxidant activity assays, and in all cases a positive effect was established: M+ was statistically more effective in comparison with kaolinite. A strong correlation was established between the antioxidative activity of cultivated fruiting bodies and the tested compounds (total phenolic compounds, carbohydrates, and minerals).


Assuntos
Carpóforos/fisiologia , Grifola/fisiologia , Zeolitas , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo , Carboidratos , Meios de Cultura , Espectroscopia de Ressonância Magnética , Picratos , Polissacarídeos/química , Polissacarídeos/metabolismo , Esporos Fúngicos
16.
Jundishapur J Microbiol ; 9(9): e34804, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27800143

RESUMO

BACKGROUND: The highest incidence of listeriosis, due to consumption of ready-to-eat foods and fresh, shredded, minimally processed vegetables, occurs among pregnant women and the elderly. In order to reduce the prevalence of listeriosis among consumers, better protective measures are recommended. Chitosan films, with or without added essential oils, represent a modern, safe method of preserving the quality of such vegetables and significantly reducing the incidence of Listeria monocytogenes in these foods. OBJECTIVES: The present study was conducted to evaluate the antimicrobial properties of composite chitosan-gelatin films with and without essential oils against two strains of L. monocytogenes, ATCC 19115 and ATCC 19112, in fresh shredded cabbage. METHODS: Shredded cabbage was inoculated with L. monocytogenes and packed between two layers of the chitosan composite film, then placed in Petri dishes. The prepared samples were stored at 4°C then analyzed for total viable count on PALCAM agar while incubated at 37°C, every 24 hours for 7 days. RESULTS: Average L. monocytogenes content ranged from 4.2 - 5.4 log CFU/g, reaching values of 7.2 - 8.6 log CFU/g in samples of untreated cabbage. A complete reduction of L. monocytogenes ATCC 19115 on cabbage was achieved after 120 hours in the presence of 0.5% chitosan film, whereas reduction of L. monocytogenes ATCC 19112 was achieved after 144 hours. In the presence of 1% chitosan film, the bacteria withered more quickly and complete reduction of both species of L. monocytogenes was achieved after 96 hours. CONCLUSIONS: All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of both strains of L. monocytogenes on cabbage. The best effect was achieved with a 1% chitosan concentration. The addition of essential oils increased the antimicrobial activity of all tested films.

17.
Rev. argent. microbiol ; 48(2): 128-136, jun. 2016. graf, tab
Artigo em Inglês | LILACS | ID: biblio-843157

RESUMO

The antibacterial activity of chitosan coatings prepared with acetic or lactic acid, as well as of composite chitosan-gelatin films prepared with essential oils, was evaluated in fresh shredded black radish samples inoculated with Listeria monocytogenes ATCC 19115 and L. monocytogenes ATCC 19112 during seven days of storage at 4 °C. The chitosan coating prepared with acetic acid showed the most effective antibacterial activity. All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of L. monocytogenes on black radish, although a higher inhibition of pathogens was achieved at higher concentrations of chitosan. The antimicrobial effect of chitosan films was even more pronounced with the addition of essential oils. Chitosan-gelatin films with thyme essential oils showed the most effective antimicrobial activity. A reduction of 2.4 log10 CFU/g for L. monocytogenes ATCC 19115 and 2.1 log10 CFU/g for L. monocytogenes ATCC 19112 was achieved in the presence of 1% chitosan film containing 0.2% of thyme essential oil after 24 h of storage.


Se evaluó la actividad antimicrobiana de coberturas del quitosano y de películas compuestas de quitosano-gelatina en muestras frescas de rábano negro cortado inoculadas con las cepas de Listeria monocytogenes ATCC 19115 y ATCC 19112, almacenadas durante 7 días a 4 °C. Las primeras fueron preparadas con ácido acético o ácido láctico, las segundas con aceites esenciales. Las coberturas de quitosano preparadas con ácido acético mostraron la actividad antimicrobiana más eficaz. Todas las formulaciones de películas de quitosano exploradas mostraron una fuerte actividad antimicrobiana sobre el crecimiento de L. monocytogenes, aunque la mayor inhibición de estos patógenos se logró con las mayores concentraciones de quitosano. La actividad antimicrobiana de las películas de quitosano fue mayor con la adición de aceite esencial. Las películas de quitosano-gelatina con aceite esencial del tomillo fueron las que mostraron la actividad antimicrobiana más eficiente. A las 24 h de almacenamiento, la película con 1% de quitosano y 0,2% de aceite esencial de tomillo produjo una reducción de 2,4 log10 UFC/g en L. monocytogenes ATCC 19115, y de 2,1 log10 UFC/g en L. monocytogenes ATCC 19112.


Assuntos
Humanos , Óleos Voláteis/farmacologia , Raphanus/microbiologia , Thymus (Planta)/química , Quitosana/farmacologia , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Sensação , Solventes/farmacologia , Qualidade dos Alimentos , Ácido Acético/farmacologia , Ácido Láctico/farmacologia , Armazenamento de Alimentos , Carga Bacteriana , Manipulação de Alimentos , Gelatina
18.
Rev Argent Microbiol ; 48(2): 128-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27237426

RESUMO

The antibacterial activity of chitosan coatings prepared with acetic or lactic acid, as well as of composite chitosan-gelatin films prepared with essential oils, was evaluated in fresh shredded black radish samples inoculated with Listeria monocytogenes ATCC 19115 and L. monocytogenes ATCC 19112 during seven days of storage at 4°C. The chitosan coating prepared with acetic acid showed the most effective antibacterial activity. All tested formulations of chitosan films exhibited strong antimicrobial activity on the growth of L. monocytogenes on black radish, although a higher inhibition of pathogens was achieved at higher concentrations of chitosan. The antimicrobial effect of chitosan films was even more pronounced with the addition of essential oils. Chitosan-gelatin films with thyme essential oils showed the most effective antimicrobial activity. A reduction of 2.4log10CFU/g for L. monocytogenes ATCC 19115 and 2.1log10CFU/g for L. monocytogenes ATCC 19112 was achieved in the presence of 1% chitosan film containing 0.2% of thyme essential oil after 24h of storage.


Assuntos
Quitosana/farmacologia , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Óleos Voláteis/farmacologia , Raphanus/microbiologia , Thymus (Planta)/química , Ácido Acético/farmacologia , Carga Bacteriana , Manipulação de Alimentos , Qualidade dos Alimentos , Armazenamento de Alimentos , Gelatina , Humanos , Ácido Láctico/farmacologia , Sensação , Solventes/farmacologia
19.
J Enzyme Inhib Med Chem ; 31(6): 915-23, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26247353

RESUMO

Antiproliferative and antibacterial activities of nine glutarimide derivatives (1-9) were reported. Cytotoxicity of compounds was tested toward three human cancer cell lines, HeLa, K562 and MDA-MB-453 by MTT assay. Compound 7 (2-benzyl-2-azaspiro[5.11]heptadecane-1,3,7-trione), containing 12-membered ketone ring, was found to be the most potent toward all tested cell lines (IC50 = 9-27 µM). Preliminary screening of antibacterial activity by a disk diffusion method showed that Gram-positive bacteria were more susceptible to the tested compounds than Gram-negative bacteria. Minimum inhibitory concentration (MIC) determined by a broth microdilution method confirmed that compounds 1, 2, 4, 6-8 and 9 inhibited the growth of all tested Gram-positive and some of the Gram-negative bacteria. The best antibacterial potential was achieved with compound 9 (ethyl 4-(1-benzyl-2,6-dioxopiperidin-3-yl)butanoate) against Bacillus cereus (MIC 0.625 mg/mL; 1.97 × 10(-3 )mol/L). Distinction between more and less active/inactive compounds was assessed from the pharmacophoric patterns obtained by molecular interaction fields.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Piperidonas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células HeLa , Humanos , Células K562 , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Piperidonas/síntese química , Piperidonas/química , Relação Estrutura-Atividade
20.
Molecules ; 20(10): 19489-525, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26516828

RESUMO

Oxidative stress caused by an imbalanced metabolism and an excess of reactive oxygen species (ROS) lead to a range of health disorders in humans. Our endogenous antioxidant defense mechanisms and our dietary intake of antioxidants potentially regulate our oxidative homeostasis. Numerous synthetic antioxidants can effectively improve defense mechanisms, but because of their adverse toxic effects under certain conditions, preference is given to natural compounds. Consequently, the requirements for natural, alternative sources of antioxidant foods identified in edible mushrooms, as well as the mechanistic action involved in their antioxidant properties, have increased rapidly. Chemical composition and antioxidant potential of mushrooms have been intensively studied. Edible mushrooms might be used directly in enhancement of antioxidant defenses through dietary supplementation to reduce the level of oxidative stress. Wild or cultivated, they have been related to significant antioxidant properties due to their bioactive compounds, such as polyphenols, polysaccharides, vitamins, carotenoids and minerals. Antioxidant and health benefits, observed in edible mushrooms, seem an additional reason for their traditional use as a popular delicacy food. This review discusses the consumption of edible mushrooms as a powerful instrument in maintaining health, longevity and life quality.


Assuntos
Agaricales/química , Antioxidantes/química , Extratos Vegetais/farmacologia , Verduras/química , Antioxidantes/farmacologia , Suplementos Nutricionais/análise , Humanos , Longevidade/efeitos dos fármacos , Extratos Vegetais/química , Qualidade de Vida
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