RESUMEN

Aquatic products are highly susceptible to spoilage, and preparing composite edible film with essential oil is an effective solution. In this study, composite edible films were prepared using perilla essential oil (PEO)-glycerol monolaurate emulsions incorporated with chitosan and nisin, and the film formulation was optimized by response surface methodology. These films were applied to ready-to-eat fish balls and evaluated over a period of 12 days. The films with the highest inhibition rate against Staphylococcus aureus were acquired using a polymer composition of 6 µL/mL PEO, 18.4 µg/mL glycerol monolaurate, 14.2 mg/mL chitosan, and 11.0 µg/mL nisin. The fish balls coated with the optimal edible film showed minimal changes in appearance during storage and significantly reduced total bacterial counts and total volatile basic nitrogen compared to the control groups. This work indicated that the composite edible films containing essential oils possess ideal properties as antimicrobial packaging materials for aquatic foods.

Asunto(s)

Antibacterianos , Quitosano , Películas Comestibles , Emulsiones , Embalaje de Alimentos , Lauratos , Monoglicéridos , Nisina , Aceites Volátiles , Staphylococcus aureus , Nisina/farmacología , Nisina/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Lauratos/química , Lauratos/farmacología , Embalaje de Alimentos/instrumentación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Emulsiones/química , Quitosano/química , Quitosano/farmacología , Monoglicéridos/química , Monoglicéridos/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Aceites de Plantas/química , Aceites de Plantas/farmacología , Perilla/química

RESUMEN

Penicillium species are renowned for their ability to produce a wide range of secondary metabolites with medicinal properties. In this study, compounds 1-10 were isolated from Penicillium sp. Z-16, of which compound 1 is a new benzophenone derivative named methyl 2-(2,6-dihydroxy-4-methylbenzoyl)-4,5-dihydroxy-3-methoxybenzoate. The chemical structure of 1 was determined through comprehensive spectroscopic analysis, including 1D, 2D NMR (HMBC, HSQC) and HRESIMS. In addition, six other known compounds (11-16) were isolated and identified from Penicillium sp. T-5-1. The antimicrobial activity tests demonstrated that compound 1 was moderately active against Candida albicans with a MIC value of 125 µg/mL, while compound 2 showed a MIC value of 62.5 µg/mL against Staphylococcus aureus.

RESUMEN

Sonodynamic antimicrobial chemotherapy (SACT), as a novel anti-infective program, has received tremendous attention due to its good tissue penetration depth and low invasion. Ultrasound (US) frequency was one of the important parameters for SACT. To investigate the influence of different US frequencies on sonodynamic antimicrobial activity of ciprofloxacin-capped gold nanoparticles (CIP:GNPs). C. albicans and E. coli were chosen as the action objects. The bacterial survival rate was used in the assessment index and measured by plate colony-counting methods. The reactive oxygen species (ROS) produced under US irradiation were detected by ROS fluorescence probe and used to analyze the sonodynamic antibacterial mechanism of CIP:GNPs following different US frequencies. High-frequency US combined with CIP:GNPs had a good synergistic antimicrobial impact on C. albicans, while medium-frequency US showed a strong effect on E. coli. Moreover, the mechanism research experiment proved that intracellular ROS levels were closely related to changes in US frequency, and significantly affected the synergistic activity of CIP:GNPs. The injury of E. coli appearance showed more sensitivity to the change of US frequency than that of C. albicans, but its action laws were relatively complicated and needed to be further studied.

RESUMEN

This research aims to maximize the extraction of phenolic compounds (PCs) from almond hull waste (AHW) using an ultrasound-assisted extraction (UAE) method, detect the PCs, and investigate the antimicrobial activity of the extracts against pathogens and interactions with a probiotic bacterium. The impact of various parameters including sonication amplitude, solvent/AHW ratio (mL/g), and extraction time on the total phenolic content (TPC) was investigated and the optimized extraction conditions were determined. The AHW extracts' minimum bacterial concentration (MBC) and minimum inhibitory concentration (MIC) against Staphylococcus aureus, Escherichia coli, and Lactobacillus plantarum were assessed. In optimal UAE conditions total PCs of 47.37 ± 0.24 mg gallic acid equivalent (GAE)/g dry weight (DW) were extracted. The HPLC analysis revealed that the flavonoid rutin, as well as p-coumaric acid and rosmarinic acid, were only seen in the extracts obtained by UAE. Furthermore, p-coumaric acid emerged as the most prevalent PC in the UAE extract. Antimicrobial activity analysis showed that UAE extracts exhibited higher effects in inhibiting the growth of E. coli, S. aureus, and L. plantarum. The use of UAE treatment resulted in the extraction of a diverse range of PCs with increased antioxidant capacity and antimicrobial activity. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05969-3.

RESUMEN

One new quinazoline-containing diketopiperazine (1), along with 24 known compounds including nine alkaloids (2-9, and 25), thirteen lactones (10-22), aspterric acid (23), and catechol (24), were isolated from the marine sponge-derived Penicillium sp. SCSIO41043. Their planar structures were unequivocally elucidated by spectroscopic analysis. The absolute configuration of 1 was determined by a comparison of reported and experimental electronic circular dichroism (ECD) spectra. Compound 16 was found to notably inhibit the growth of five pathogenic bacteria and fungi with MIC values ranging from 0.5-16.0 µg/mL. Compounds 7, 17, 20, and 22 demonstrated moderate activity against Micrococcus luteus with MIC values ranging from 35.6 to 71.1 µg/mL. Moreover, 1-3 displayed different degrees of antioxidant activity with EC50 values of 0.98, 0.60, 0.46 mg/mL, respectively.

RESUMEN

The advancement of wearable supercapacitors (SCs) has recently garnered a lot of attention owing to their ease of fabrication into textiles, low cost, long cycle life, fast charging and discharging, high efficiency, and ability to bridge the energy and power gap between conventional capacitors and batteries. The present study focuses on the development of wearable textile-based SC electrodes using green-synthesised manganese oxide nanoparticles functionalised on poly(o-phenylenediamine) reinforced to a polymer nanocomposite. The prepared nanocomposite was characterized using spectroscopic techniques such as UV-visible spectroscopy, Fourier transform infrared spectroscopy, x-ray diffraction studies, and scanning electron microscopy to validate the incorporation of metal oxide nanoparticles into the polymer matrix. The thermal properties were studied using thermogravimetric analysis and differential scanning calorimetry. The electrochemical performance of the bare polymer and the nanocomposite was evaluated using cyclic voltammetry, galvanostatic charge-discharge, and impedance spectroscopy techniques. An impressive specific capacitance of 213 Fg-1was achieved at a current density of 1 Ag-1for the polymer nanocomposite and even after 1000 cycles a capacitance retention of 89% was observed. Enhanced antimicrobial activity was also observed for the nanocomposite against both gram-negative and gram-positive bacteria. Based on these attributes, the fabricated device can be used as an efficient antimicrobial wearable SC.

RESUMEN

This research studied the phenolic content compared with the antioxidant properties of various O. vulgare (Lamiaceae) cultivars grown in Poland. The research results in this paper indicate that the dominant ingredient in all oregano cultivars was rosmarinic acid, known for its strong antioxidant properties. The highest amounts of rosmarinic acid (87.16 ± 4.03 mg/g dm) were identified in the O. vulgare spp. hirtum (Link) Ietsw. Other metabolites identified in the studied extracts include luteolin O-di-glucuronide-O-di-pentoside (30.79 ± 0.38 mg/g dm in the 'Aureum' cultivar), 4'-O-glucopyranosyl-3', 4'-dihydroxy benzyl-protocatechuate (19.84 ± 0.60 mg/g dm in the 'Margerita' cultivar), and p-coumaroyl-triacetyl-hexoside (25.44 ± 0.18 mg/g dm in the 'Margerita' cultivar). 'Hot & spicy' and 'Margerita' cultivars were characterized by the highest activity in eliminating OH• and O2•- radicals. Extracts from Greek oregano had the highest ability to scavenge DPPH radicals and chelate iron ions. This research has also provided new evidence that oregano has anti-migratory, cytotoxic properties and influences the viability of gastric cancer cells (the highest cytotoxicity was attributed to the 'Hot & spicy' cultivar, which performed the worst in antioxidant properties tests). Extracts from the tested cultivars at a concentration of 0.625% effectively inhibited the growth of S. aureus and P. aeruginosa bacteria. It seems that the oregano grown in Poland is of good quality and can be successfully grown on a large scale if the appropriate use is found.

Asunto(s)

Antioxidantes , Origanum , Extractos Vegetales , Origanum/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Polonia , Antioxidantes/farmacología , Antioxidantes/química , Humanos , Fenoles/farmacología , Fenoles/análisis , Fenoles/química , Cinamatos/química , Cinamatos/farmacología , Cinamatos/análisis , Antibacterianos/farmacología , Antibacterianos/química , Depsidos/farmacología , Depsidos/química , Ácido Rosmarínico , Línea Celular Tumoral

RESUMEN

Chalcones, secondary plant metabolites, exhibit various biological properties. The introduction of a chlorine and a glucosyl substituent to the chalcone could enhance its bioactivity and bioavailability. Such compounds can be obtained through a combination of chemical and biotechnological methods. Therefore, 4-chloro-2'-hydroxychalcone and 5'-chloro-2'-hydroxychalcone were obtained by synthesis and then glycosylated in two filamentous fungi strains cultures, i.e., Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5. The main site of the glycosylation of both compounds by I. fumosorosea KCH J2 was C-2' and C-3 when the second strain was utilized. The pharmacokinetics of these compounds were predicted using chemoinformatics tools. Furthermore, antimicrobial activity tests were performed. Compounds significantly inhibited the growth of the bacteria strains Escherichia coli 10536, Staphylococcus aureus DSM 799, and yeast Candida albicans DSM 1386. Nevertheless, the bacterial strain Pseudomonas aeruginosa DSM 939 exhibited significant resistance to their effects. The growth of lactic acid bacteria strain Lactococcus acidophilus KBiMZ 01 bacteria was moderately inhibited, but strains Lactococcus rhamnosus GG and Streptococcus thermophilus KBM-1 were completely inhibited. In summary, chalcones substituted with a chlorine demonstrated greater efficacy in inhibiting the microbial strains under examination compared to 2'-hydroxychalcone, while aglycones and their glycosides exhibited similar effectiveness.

Asunto(s)

Antiinfecciosos , Chalconas , Cloro , Glicósidos , Pruebas de Sensibilidad Microbiana , Chalconas/química , Chalconas/farmacología , Glicósidos/química , Glicósidos/farmacología , Antiinfecciosos/farmacología , Antiinfecciosos/química , Cloro/química , Beauveria

RESUMEN

Oral health is essential for both overall health and quality of life. The mouth is a window into the body's health, and nutrition can strongly impact the state of general and oral health. A healthy diet involves the synergistic effect of various nutraceutical agents, potentially capable of conferring protective actions against some inflammatory and chronic-degenerative disorders. Nutraceuticals, mostly present in plant-derived products, present multiple potential clinical, preventive, and therapeutic benefits. Accordingly, preclinical and epidemiological studies suggested a protective role for these compounds, but their real preventive and therapeutic effects in humans still await confirmation. Available evidence suggests that plant extracts are more effective than individual constituents because they contain different phytochemicals with multiple pharmacological targets and additive/synergistic effects, maximizing the benefits for oral health. Moreover, nutritional recommendations for oral health should be personalized and aligned with valid suggestions for overall health. This review is aimed to: introduce the basic concepts of nutraceuticals, including their main food sources; examine the logic that supports their relationship with oral health, and summarize and critically discuss clinical trials testing the utility of nutraceuticals in the prevention and treatment of oral diseases.

Asunto(s)

Suplementos Dietéticos , Salud Bucal , Humanos , Extractos Vegetales/uso terapéutico , Extractos Vegetales/farmacología , Fitoquímicos/uso terapéutico , Fitoquímicos/farmacología , Calidad de Vida , Animales

RESUMEN

The utilization of biopolymers incorporated with antimicrobial agents is extremely interesting in the development of environmentally friendly functional materials for food packaging and other applications. In this study, the effect of calcium oxide (CaO) on the morphological, mechanical, thermal, and hydrophilic properties as well as the antimicrobial activity of carboxymethyl chitosan (CMCH) bio-composite films was investigated. The CMCH was synthesized from shrimp chitosan through carboxymethylation, whereas the CaO was synthesized via a co-precipitation method with polyethylene glycol as a stabilizer. The CMCH-CaO bio-composite films were prepared by the addition of synthesized CaO into the synthesized CMCH using a facile solution casting method. As confirmed by XRD and SEM, the synthesized CaO has a cubic shape, with an average crystalline size of 25.84 nm. The synthesized CaO exhibited excellent antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) (>99.9% R). The addition of CaO into CMCH improved the mechanical and hydrophobic properties of the CMCH-CaO films. However, it resulted in a slight decrease in thermal stability. Notably, the CMCH-CaO10% films exhibited exceptional antimicrobial activity against E. coli (98.8% R) and S. aureus (91.8% R). As a result, such bio-composite films can be applied as an active packaging material for fruit, vegetable, or meat products.

RESUMEN

This article investigates the activation of surface groups of poly(ethylene terephthalate) (PET) fibers in woven fabric by hydrolysis and their functionalization with chitosan. Two types of hydrolysis were performed-alkaline and enzymatic. The alkaline hydrolysis was performed in a more sustainable process at reduced temperature and time (80 °C, 10 min) with the addition of the cationic surfactant hexadecyltrimethylammonium chloride as an accelerator. The enzymatic hydrolysis was performed using Amano Lipase A from Aspergillus niger (2 g/L enzyme, 60 °C, 60 min, pH 9). The surface of the PET fabric was functionalized with the homogenized gel of biopolymer chitosan using a pad-dry-cure process. The durability of functionalization was tested after the first and tenth washing cycle of a modified industrial washing process according to ISO 15797:2017, in which the temperature was lowered from 75 °C to 50 °C, and ε-(phthalimido) peroxyhexanoic acid (PAP) was used as an environmentally friendly agent for chemical bleaching and disinfection. The influence of the above treatments was analyzed by weight loss, tensile properties, horizontal wicking, the FTIR-ATR technique, zeta potential measurement and SEM micrographs. The results indicate better hydrophilicity and effectiveness of both types of hydrolysis, but enzymatic hydrolysis is more environmentally friendly and favorable. In addition, alkaline hydrolysis led to a 20% reduction in tensile properties, while the action of the enzyme resulted in a change of only 2%. The presence of chitosan on polyester fibers after repeated washing was confirmed on both fabrics by zeta potential and SEM micrographs. However, functionalization with chitosan on the enzymatically bioactivated surface showed better durability after 10 washing cycles than the alkaline-hydrolyzed one. The antibacterial activity of such a bio-innovative modified PET fabric is kept after the first and tenth washing cycles. In addition, applied processes can be easily introduced to any textile factory.

RESUMEN

Research on lemon grass (Cymbopogon citratus L.) revealed a variety of active molecules and examined their biological characteristics. However, most of these studies were conducted on wild varieties, while cultivated plants were addressed less. This study aimed to characterize the biomolecules and biological activities of lemon grass growing under North African conditions in Morocco. Phenolic compound profiles of aqueous (AE), ethanol (EE), and methanol (ME) extracts and their fractions were obtained with steric exclusion chromatography on Sephadex G50 gel and identified by LC-MS/MS. Then, total polyphenols (TPC), flavonoids (TFC), and antioxidant activities (FRAP: scavenging value and TAC: Total Antioxidant Capacity) of the fraction were evaluated, as well as the antimicrobial activity. The obtained results showed that the ME contained eight major compounds (i.e., apigenine-7-O-rutinoside and myricitine-3-O-rutinoside). The AE showed the presence of five molecules (i.e., kaempferol-3-O-glucuronide), while EE showed the presence of three molecules (i.e., quercetine-3-O-rutinoside). Regarding the chemical characterization, the highest value of total phenolic content (TPC) was obtained in AE (25) (4.60 ± 0.29 mg/g), and the highest value of total flavonoid content (TFC) was obtained in ME (29) (0.7 ± 0.08 mg/g). Concerning the antioxidant activity, the highest FRAP was obtained in ME (29) (97.89%), and the highest total antioxidant capacity (TAC) was obtained in ME (29) (89.89%). Correlation between FRAP, TPC, and TFC was noted only in fractions of AE and ME. All tested extracts of C. citratus and their fractions showed a significant antimicrobial effect. The lowest minimum inhibitory concentration (MIC) was recorded for ME against E. coli. Extracts' biological activities and their fractions were governed by their active molecules. These data are new and clarify a novel aspect of bioactive molecules in the extracts of cultivated C. citratus. Equally, throughout this research, we clarified the relationship between identified molecules and their biological properties, including antioxidant and anti-microbial activities, which is new for the study area. This study is suggested as a reference for comparative studies and other assays of other biological activities for the study plant.

Asunto(s)

Antioxidantes , Cymbopogon , Flavonoides , Extractos Vegetales , Antioxidantes/farmacología , Antioxidantes/química , Cymbopogon/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Flavonoides/química , Flavonoides/farmacología , Flavonoides/análisis , Marruecos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Peso Molecular , Espectrometría de Masas en Tándem , Polifenoles/química , Polifenoles/farmacología , Fenoles/química , Fenoles/farmacología , Fenoles/análisis , Pruebas de Sensibilidad Microbiana , Cromatografía Liquida

RESUMEN

This work presents the results of studying dilute aqueous solutions of commercial Ln(NO3)3 · xH2O salts with Ln = Ce-Lu using X-ray diffraction (XRD), IR spectroscopy, X-ray absorption spectroscopy (XAS: EXAFS/XANES), and pH measurements. As a reference point, XRD and XAS measurements for characterized Ln(NO3)3 · xH2O microcrystalline powder samples were performed. The local structure of Ln-nitrate complexes in 20 mM Ln(NO3)3 · xH2O aqueous solution was studied under total external reflection conditions and EXAFS geometry was applied to obtain high-quality EXAFS data for solutions with low concentrations of Ln3+ ions. Results obtained by EXAFS spectroscopy showed significant contraction of the first coordination sphere during the dissolution process for metal ions located in the middle of the lanthanide series. It was established that in Ln(NO3)3 · xH2O solutions with Ln = Ce, Sm, Gd, Yb (c = 134, 100, 50 and 20 mM) there are coordinated and, to a greater extent, non-coordinated nitrate groups with bidentate and predominantly monodentate bonds with Ln ions, the number of which increases upon transition from cerium to ytterbium. For the first time, the antibacterial and antifungal activity of Ln(NO3)3 · xH2O Ln = Ce, Sm, Gd, Tb, Yb solutions with different concentrations and pH was presented. Cross-relationships between the concentration of solutions and antimicrobial activity with the type of Ln = Ce, Sm, Gd, Tb, Yb were established, as well as the absence of biocidal properties of solutions with a concentration of 20 mM, except for Ln = Yb. The important role of experimental conditions in obtaining and interpreting the results was noted.

RESUMEN

As an important small organic molecule, cyclopropane is widely used in drug design. In this paper, fifty-three amide derivatives containing cyclopropane were designed and synthesized by introducing amide groups and aryl groups into cyclopropane through the active splicing method, and their antibacterial and antifungal activities were evaluated in vitro. Among them, thirty-five compounds were new compounds, and eighteen compounds were known compounds (F14, F15, F18, F20-F26, F36, and F38-F44). Bioassay results disclosed that four, three, and nine of the compounds showed moderate activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, respectively. Three compounds were sensitive to Candida albicans, with excellent antifungal activity (MIC80 = 16 µg/mL). The molecular docking results show that compounds F8, F24, and F42 have good affinity with the potential antifungal drug target CYP51 protein.

Asunto(s)

Amidas , Antifúngicos , Candida albicans , Ciclopropanos , Diseño de Fármacos , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Staphylococcus aureus , Ciclopropanos/farmacología , Ciclopropanos/química , Ciclopropanos/síntesis química , Amidas/química , Amidas/farmacología , Amidas/síntesis química , Candida albicans/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antifúngicos/farmacología , Antifúngicos/síntesis química , Antifúngicos/química , Escherichia coli/efectos de los fármacos , Relación Estructura-Actividad , Antiinfecciosos/farmacología , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Estructura Molecular

RESUMEN

Waste from the agri-food chain represents a valuable reservoir of organic compounds with health-promoting properties. Momast Plus 30 Bio (MP30B) is a derivative obtained from olive-oil wastewater. Its enrichment in hydroxytyrosol (HT) via a patented technique has paved the way for its potential application as a dietary supplement in preventing cardiovascular diseases. MP30B demonstrates no significant alteration in cardiac and vascular parameters in "ex vivo" studies. However, it exhibits a strong ability to remove reactive oxygen species and exerts anti-inflammatory effects, notably reducing the concentration of iNOS and mitigating heart infections in "in vitro" experiments. Furthermore, MP30B slightly decreases the stiffness of the "ex vivo" thoracic aorta, potentially resulting in lowered arterial pressure and enhanced energy transfer to a normal ventricle. Based on these findings, we posit MP30B as a promising extract for cardiovascular disease prevention, and its specific antibacterial properties suggest its utility in preventing cardiac infections.

Asunto(s)

Enfermedades Cardiovasculares , Olea , Aguas Residuales , Aguas Residuales/química , Enfermedades Cardiovasculares/prevención & control , Olea/química , Humanos , Aceite de Oliva/química , Animales , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/farmacología , Especies Reactivas de Oxígeno/metabolismo , Suplementos Dietéticos , Residuos Industriales/análisis , Antiinflamatorios/farmacología

RESUMEN

Gelatin (Gel) based water-insoluble films with antimicrobial properties were developed by the green method using trans-cinnamaldehyde (TCA) and low-energy X-ray irradiation as dual crosslinkers. The Gel/TCA composite films (GTCF) were prepared at different pH (4, 6, 8, and 10) and crosslinked by incorporating 5 % (w/w, based on Gel) TCA and X-ray irradiation (350 kV and 11.4 mA) with doses of 0, 5, 10 and 15 kGy. The presence of TCA in GTCF forms dense, flexible, and strong films when exposed to X-ray irradiation. The GTCF at pH 6, incorporated with 5 wt% TCA and irradiated with 10 kGy X-ray, displayed the highest degree of crosslinking (DOC) (93.4 ±â€¯3.4 %), tensile strength, excellent UV-barrier (> 99.9 %), antimicrobial (inhibitory capacity of >50 %), and water vapor permeability (4.1 ±â€¯0.6 g.mm/m2.day. kPa), and low solubility in water (0.5 ±â€¯0.3 %), and oxygen permeability. The GTCF, crosslinked with X-ray irradiation, has multifunctional properties and strong potential in the sustainable packaging industry to augment the shelf life of food and reduce food waste. To the best of our information, this is the first and novel report investigating the effects of pH on the properties of GTCF crosslinked with X-ray.

RESUMEN

This research adopted the Fischer indole synthesis method to continue constructing a novel drug-like chemical entity based on the guidance of isocryptolepine and obtained four series of derivatives: Y, Da, Db, and Dc. The antimicrobial activity of these derivatives against plant pathogens was further evaluated. The results showed that Dc-2 had the best antifungal effect against Botrytis cinerea, and its EC50 value was up to 1.29 µg/mL. In addition, an in vivo activity test showed that the protective effect of Dc-2 on apples was 82.2% at 200 µg/mL, which was better than that of Pyrimethanil (45.4%). Meanwhile, it was found by scanning electron microscopy and transmission electron microscopy that the compound Dc-2 affected the morphology of mycelia. The compound Dc-2 was found to damage the cell membrane by PI and ROS staining. Through experiments such as leakage of cell contents, it was found that the compound Dc-2 changed the permeability of the cell membrane and caused the leakage of substances in the cell. According to the above studies, compound Dc-2 can be used as a candidate lead compound for further structural optimization and development.

RESUMEN

Herbal medicines are important for ensuring sustainable development goals (SDGs) in healthcare, particularly in developing countries with high rates of antimicrobial resistance (AMR) and little access to medical facilities. Thymus vulgaris is a widely used herbal medicinal plant known for its secondary metabolites and antimicrobial properties. The present study involved a comprehensive examination of the isolation, characterization, and antibacterial activity of Thymus vulgaris obtained from Ethiopia. The aerial part of the plant Thymus vulgaris was successively extracted with hexane, chloroform, and methanol based on differences in polarity. Phytochemical screening tests conducted against hexane, chloroform and MeOH crude extracts indicated the presence of some secondary metabolites. Based on the thin-layer chromatography tests, the chloroform extract was subjected to column chromatography, yielding Tv-2 compounds, namely 5-isopropyl-2-methylphenol. The structures of the compounds were elucidated via spectroscopic methods (UV-Vis, FT-IR and NMR). We investigated the antibacterial properties of hexane crude extract, chloroform crude extract, MeOH crude extract, and isolated fractions derived from T. vulgaris against various bacterial strains. This study contributes to a better understanding of the bioactive components present in Thymus vulgaris crude extracts and their potential role in tackling microbial infections.

Asunto(s)

Antibacterianos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Thymus (Planta) , Thymus (Planta)/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Etiopía , Bacterias/efectos de los fármacos , Fitoquímicos/farmacología , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación

RESUMEN

Historically, tree sap has been used globally for medicinal purposes, in fermented beverages, and for syrup production. Maple tree sap is notably concentrated into syrup and is valued as a natural sweetener rich in phenolic compounds and minerals compared to refined sugar. Recently, syrups from other trees like black walnut (Juglans nigra) and sycamore (Platanus occidentalis) have gained popularity, yet their properties are not well understood scientifically. To address this gap, we collected sycamore, black walnut, and maple syrup samples and analyzed their physicochemical and functional properties. Our findings showed significant differences among the syrups in pH, browning intensity, and water activity (p < 0.05). Sycamore syrup had the highest total phenolic content, followed by black walnut and maple syrups. Both black walnut and sycamore syrups exhibited similar antioxidant activity, significantly higher than maple syrup (p < 0.05). High-resolution mass spectrometry identified 54 phenolic acids and 22 flavonoids in these syrups, including Acetylsalicylic acid, 3,5-Dihydroxybenzoic acid, and syringic acid, known for their antioxidant and anti-inflammatory properties. Additionally, sycamore syrups and most black walnut syrups displayed varying degrees of antimicrobial activity against Gram-positive and/or Gram-negative microorganisms. This study offers insights into the properties and potential health benefits of these specialty tree syrups.

RESUMEN

Bacteriocins are a class of proteins produced by bacteria that are toxic to other bacteria. These bacteriocins play a role in bacterial competition by helping to inhibit potential competitors. In this study, we isolated and purified a novel bacteriocin Pkmh, different from the previously reported bacteriocin PA166, from Pseudomonas sp. strain 166 by ammonium sulfate precipitation, dialysis membrane method, ion exchange chromatography, and gel filtration chromatography. SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) revealed that the molecular weight of Pkmh is approximately 35 kDa. Pkmh exhibited potent antimicrobial activity against bovine Mannheimia haemolytica (M. haemolytica) with low cytotoxicity, and lower hemolytic activity was observed. In addition, Pkmh retained antimicrobial activity at different pH ranges (2-10) and temperature conditions (40, 60, 80, 100 °C). Our analysis of its antimicrobial mechanism showed that Pkmh acts on bacterial cell membranes, increasing their permeability and leading to cell membrane rupture and death. In conclusion, Pkmh exhibited low hemolytic activity, low toxicity, and potent antibacterial effects, suggesting its potential as a promising candidate for clinical therapeutic drugs.

Asunto(s)

Antibacterianos , Bacteriocinas , Bacteriocinas/farmacología , Bacteriocinas/química , Antibacterianos/farmacología , Antibacterianos/química , Animales , Hemólisis/efectos de los fármacos , Mannheimia haemolytica/efectos de los fármacos , Pseudomonas/efectos de los fármacos , Bovinos , Pruebas de Sensibilidad Microbiana , Humanos , Peso Molecular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Temperatura , Concentración de Iones de Hidrógeno