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1.
Meat Sci ; 210: 109424, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38219545

RESUMO

Droëwors (dried sausage) is a unique dried meat product from South Africa, which is not smoked, fermented, nor is nitrite used in its production. The objective of the study was to compare the quality parameters and consumer acceptance of common eland meat droëwors with different quantities of added beef fat. Three treatments containing either 10, 15, or 20% (by weight) added beef fat were compared regarding chemical composition, fatty acid profiles, and sensory properties. Increasing the amount of fat in the dried product resulted in a significant decrease in the protein and ash percentages. The sausages with 10% added fat had the most favourable fatty acid profile in terms of nutritional value. Several differences were found in the sensory profiles of the products evaluated by the trained sensory panel; in particular, the evaluation scores for texture improved with increasing fat content. No differences were found between the products by the untrained consumer panel for appearance and taste. When the dataset was analysed according to gender, it was found that women evaluated the 10% fat samples more favourably. This is in line with their stated preference for low-fat meat products. For these reasons, the production of sausages with the lowest fat content can be recommended as they best meet consumer expectations.


Assuntos
Produtos da Carne , Animais , Bovinos , Humanos , Feminino , Produtos da Carne/análise , Manipulação de Alimentos/métodos , Paladar , Carne/análise , Ácidos Graxos/análise , Comportamento do Consumidor
2.
Front Pharmacol ; 14: 1230728, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37593173

RESUMO

Although medical cannabis was legalized in Czechia in 2013 and its use in topical treatments of skin disorders is now allowed, galenic formulations prepared from medical cannabis have not been widely implemented in the Czech healthcare system. One of the main reasons is the lack of a straightforward standardized protocol for their preparation. Cannabinoids, e.g., cannabidiol (CBD) and tetrahydrocannabinol (THC), have been shown to have therapeutic effects on various skin conditions, such as atopic dermatitis, psoriasis, scleroderma, acne and skin pigmentation. Recognizing the potential of dermatological treatment with medical cannabis, the present study aimed to evaluate the extraction capacity of various pharmaceutical bases for cannabinoids and the stability of prepared galenic formulations for dermatological applications with respect to cannabinoid content. The results showed that the stability of cannabinoids in formulations depended on the bases' physical and chemical properties. The highest THC decomposition was observed in cream bases and Vaseline, with estimated percentage loss of total content of up to 5.4% and 5.6% per week, respectively. In contrast, CBD was more stable than THC. Overall, the tested bases were comparably effective in extracting cannabinoids from plant material. However, olive oil and Synderman bases exhibited the highest cannabinoid extraction efficiencies (approximately 70%) and the best storage stabilities in terms of the content of monitored compounds. The proposed preparation protocol is fast and easily implementable in pharmacies and medical facilities.

3.
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.

4.
Animals (Basel) ; 13(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37370551

RESUMO

Antiepileptic drugs (e.g., carbamazepine; CBZ) are widely prescribed for various conditions beyond epilepsy, including neurologic and psychiatric disorders. These medications can have both favorable and unfavorable impacts on mood, anxiety, depression, and psychosis. CBZ has been found at low concentrations (in the unit of nanograms per liter) in rivers, surface water, and even drinking water. As a result, when reclaimed wastewater is used for irrigation in agricultural ecosystems, CBZ can be reintroduced into the environment. That is why we tested different doses of CBZ in rabbits' feed as the meat is consumed in every community, has no religious barriers, and the potential risk of consuming meat which has been exposed to CBZ treatment is not known. Also, the evidence of the effect of CBZ on rabbits is missing. Mainly, the CBZ doses affected the count of leukocytes and other blood traits, meaning the higher the dose, the higher the reduction. Moreover, there were only low amounts of CBZ in rabbits' meat or tissues when they were exposed to the treatment.

5.
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
6.
Chemosphere ; 329: 138689, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059200

RESUMO

The presence of pharmaceuticals in the environment is a matter of great concern. They are consistently found in the environment, raising concerns regarding human exposure through dietary intake. In this study, we observed the effect of the application of carbamazepine at 0.1, 1, 10, and 1000 µg per kg of soil contamination levels to assess stress metabolism in Zea mays L. cv. Ronaldinio at the 4th leaf, tasselling, and dent phenological stages. The transfer of carbamazepine to the aboveground and root biomass was assessed, and uptake increased dose-dependently. No direct effect on biomass production was observed, but multiple physiological and chemical changes were observed. Major effects were consistently observed at the 4th leaf phenological stage for all contamination levels, including reduced photosynthetic rate, reduced maximal and potential activity of photosystem II, decreased water potential, decreased carbohydrates (glucose and fructose) and γ-aminobutyric acid in roots, and increased maleic acid and phenylpropanoids (chlorogenic acid and its isomer, 5-O-caffeoylquinic acid) in aboveground biomass. A reduction in net photosynthesis was observed for the older phenological stages, whereas no other relevant and consistent physiological and metabolic changes related to contamination exposure were detected. Our results indicate that Z. mays can overcome the environmental stress caused by the accumulation of carbamazepine with notable metabolic changes at the early phenological stage; however, older plants adapted and only exhibited minor effects in the presence of the contaminant. The potential implications for agricultural practice could be associated with the plant's response to simultaneous stresses due to metabolite changes associated with oxidative stress.


Assuntos
Poluentes Ambientais , Zea mays , Humanos , Zea mays/metabolismo , Poluentes Ambientais/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Carbamazepina/metabolismo , Preparações Farmacêuticas/metabolismo
7.
J Fungi (Basel) ; 10(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38248933

RESUMO

Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was proposed for rapid, versatile, and non-invasive screening of Ganoderma basidiocarps to assess their potential for specific applications. Fifteen species and strains of this fungus were selected for analysis, and fine sections at different parts of young and mature basidiocarps were obtained. The spectra of fungal samples showed significant differences interpreted in terms of biochemical composition using characteristic bands of proteins, polysaccharides, lipids, and triterpenoids. Obviously, for the transverse sections in trama, especially in the basal part, the most intense bands at 950-1200 cm-1 corresponded to polysaccharide vibrations, while for the superficial sections, the bands of carbonyl and aliphatic groups of triterpenoids at 1310-1470, 1550-1740, and 2850-2980 cm-1 predominated. The pilei, especially hymenium tubes, apparently contained more proteins than the bases and stipes, as evidenced by the intense bands of amide vibrations at 1648 and 1545-1550 cm-1. The specificity of the Ganoderma basidiocarp is a densely pigmented surface layer rich in triterpenoids, as proved by ATR-FTIR spectroscopy. The spectral differences corresponding to the specificity of the triterpenoid composition may indicate the prospects of individual strains and species of this genus for cultivation and further use in food, cosmetics, or medicine.

8.
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.

9.
Meat Sci ; 192: 108912, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35863209

RESUMO

Understanding the factors affecting meat eating quality and consumer demand is essential for estimating future trends in meat consumption. The objective of the study was therefore to compare Czech and Spanish consumer attitudes and preferences in relation to beef intramuscular fat content. Three hundred and one consumers participated in the study; they completed a sociodemographic questionnaire and evaluated grilled beef samples of three varying intramuscular fat contents (low, medium, high). The low-fat meat had an average intramuscular fat content of 1.3%, medium had 3.1% and high-fat had 5.2%. Sensory assessment scores tended to show a positive linear relationship with beef intramuscular fat content. While Czech assessors only noted differences in tenderness and overall acceptance between the beef samples, Spanish assessors were able to detect significant differences in all the descriptors evaluated. Age and gender affected the assessment scores of beef with different intramuscular fat contents.


Assuntos
Comportamento do Consumidor , Paladar , Animais , Bovinos , República Tcheca , Carne/análise , Inquéritos e Questionários
10.
J Econ Entomol ; 115(5): 1472-1479, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-35674716

RESUMO

The northern yellow sac spider Cheiracanthium mildei L. Koch, is expanding its range to Central Europe, especially to synanthropic habitats. The spiders become unwanted companions because of the unreasonable fear - arachnophobia, and estetic reason - silk retreats in corners, capturing dust. The most commonly used substances against spiders are pesticides, which are, however, toxic. In our work we tested the attraction or repellence of 15 essential oils (EO) from plants representing eight families to C. mildei. Our research has shown a significant repellent effect of EO from three plants, namely Syzygium aromaticum (L.) Merr. et L. M. Perry (Myrtales: Myrtaceae), Ananas comosus (L.) Merr. (Poales: Bromeliaceae) and Musa sp. (L.) (Zingiberales: Musaceae). In contrast, some EOs appeared to have an attraction effect, particularly Carum carvi L. (Apiales: Apiaceae). Zingiber officinale Roscoe (Zingiberales: Zingiberaceae) reduced the tendency of spiders to construct the silken retreat. S. aromaticum, A. sativus, Musa sp. and Z. officinale have the potential to be used as natural repellents against spiders.


Assuntos
Repelentes de Insetos , Musa , Óleos Voláteis , Aranhas , Animais , Poeira , Repelentes de Insetos/farmacologia , Óleos Voláteis/farmacologia , Transtornos Fóbicos , Óleos de Plantas/farmacologia , Plantas , Seda
11.
Front Plant Sci ; 13: 868350, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432432

RESUMO

There is growing evidence to support the involvement of nutrients and biostimulants in plant secondary metabolism. Therefore, this study evaluated the potential of amino acid-based supplements that can influence different hydroponic nutrient cycles (systems) to enhance the cannabinoid and terpene profiles of medical cannabis plants. The results demonstrate that amino acid biostimulation significantly affected ion levels in different plant tissues (the "ionome"), increasing nitrogen and sulfur content but reducing calcium and iron content in both nutrient cycles. A significantly higher accumulation of nitrogen and sulfur was observed during the recirculation cycle, but the calcium level was lower in the whole plant. Medical cannabis plants in the drain-to-waste cycle matured 4 weeks earlier, but at the expense of a 196% lower maximum tetrahydrocannabinolic acid yield from flowers and a significantly lower concentration of monoterpene compounds than in the recirculation cycle. The amino acid treatments reduced the cannabinolic acid content in flowers by 44% compared to control in both nutritional cycles and increased the monoterpene content (limonene) up to 81% in the recirculation cycle and up to 123% in the drain-to-waste cycle; ß-myrcene content was increased up to 139% in the recirculation cycle and up to 167% in the drain-to-waste cycle. Our results suggest that amino acid biostimulant supplements may help standardize the content of secondary metabolites in medical cannabis. Further experiments are needed to identify the optimal nutrient dosage and method of administration for various cannabis chemotypes grown in different media.

12.
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
13.
Polymers (Basel) ; 14(2)2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35054662

RESUMO

In this study, we focused on the isolation and structural characterization of polysaccharides from a basidiocarp of polypore fungus Ganoderma resinaceum. Polysaccharide fractions were obtained by successive extractions with cold water at room temperature (20 °C), hot water under reflux (100 °C), and a solution of 1 mol L-1 sodium hydroxide. The purity of all fractions was controlled mainly by Fourier transform infrared (FTIR) spectroscopy, and their composition and structure were characterized by organic elemental analysis; neutral sugar and methylation analyses by gas chromatography equipped with flame ionization detector (GC/FID) and mass spectrometry detector (GC/MS), respectively; and by correlation nuclear magnetic resonance (NMR) spectroscopy. The aqueous extracts contained two main polysaccharides identified as a branched O-2-ß-d-mannosyl-(1→6)-α-d-galactan and a highly branched (1→3)(1→4)(1→6)-ß-d-glucan. Mannogalactan predominated in the cold water extract, and ß-d-glucan was the main product of the hot water extract. The hot water soluble fraction was further separated by preparative anion exchange chromatography into three sub-fractions; two of them were identified as branched ß-d-glucans with a structure similar to the corresponding polysaccharide of the original fraction. The alkaline extract contained a linear (1→3)-α-d-glucan and a weakly branched (1→3)-ß-d-glucan having terminal ß-d-glucosyl residues attached to O-6 of the backbone. The insoluble part after all extractions was identified as a polysaccharide complex containing chitin and ß-d-glucans.

14.
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.

15.
Foods ; 10(11)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34829035

RESUMO

2-arylbenzofurans represent a small group of bioactive compounds found in the plant family Moraceae. As it has not been investigated whether these substances are stable during passage through the gastrointestinal tract, their biological effects may be altered by the metabolism of intestinal microbiota or cells. The aim of the present study was to investigate and compare mulberrofuran Y (1), moracin C (2), and mulberrofuran G (3) in an in vitro model of human intestinal bacterial fermentation and in an epithelial model using the Caco-2 cell line. The analysis of compounds by LC-MS-Q-TOF showed sufficient stability in the fermentation model, with no bacterial metabolites detected. However, great differences in the quantity of permeation were observed in the permeability assay. Moreover, mulberrofuran Y (1) and moracin C (2) were observed to be transformed into polar metabolites by conjugation. Among the test compounds, mulberrofuran Y (1) was mostly stable and accumulated in endothelial cells (85.3%) compared with mulberrofuran G (3) and moracin C (2) (14% and 8.2%, respectively). Thus, only a small amount of mulberrofuran Y (1) was conjugated. Moracin C (2) and mulberrofuran G (3) were metabolized almost completely, with only traces of the unchanged molecule being found on the apical and cellular sides of the system. Only conjugates of mulberrofuran Y (1) and moracin C (2) were able to reach the basolateral side. Our results provide the basic description of bioavailability of these three compounds, which is a necessary characteristic for final evaluation of bio-efficacy.

16.
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
17.
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.

18.
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.

19.
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
20.
Front Plant Sci ; 12: 790907, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069647

RESUMO

Powdery mildew is a common disease affecting the commercial production of gerbera flowers (Gerbera hybrida, Asteraceae). Some varieties show a certain degree of resistance to it. Our objective was to identify biomarkers of resistance to powdery mildew using an 1H nuclear magnetic resonance spectroscopy and chemometrics approach in a complex, fully factorial experiment to suggest a target for selection and breeding. Resistant varieties were found to differ from those that were susceptible in the metabolites of the polyketide pathway, such as gerberin, parasorboside, and gerberinside. A new compound probably involved in resistance, 5-hydroxyhexanoic acid 3-O-ß-D-glucoside, was described for the first time. A decision tree model was built to distinguish resistant varieties, with an accuracy of 57.7%, sensitivity of 72%, and specificity of 44.44% in an independent test. Our results suggest the mechanism of resistance to powdery mildew in gerbera and provide a potential tool for resistance screening in breeding programs.

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