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This research describes the synthesis by an environmentally-friendly method, microwave irradiation, development and analysis of three novel and one previously identified Schiff base derivative as a potential inhibitor of bovine xanthine oxidase (BXO), a key enzyme implicated in the progression of gout. Meticulous experimentation revealed that these compounds (10, 9, 4, and 7) have noteworthy inhibitory effects on BXO, with IC50 values ranging from 149.56 µM to 263.60 µM, indicating their good efficacy compared to that of the standard control. The validation of these results was further enhanced through comprehensive in silico studies, which revealed the pivotal interactions between the inhibitors and the catalytic sites of BXO, with a particular emphasis on the imine group (-C = N-) functionalities. Intriguingly, the compounds exhibiting the highest inhibition rates also showcase advantageous ADMET profiles, alongside encouraging initial assessments via PASS, hinting at their broad-spectrum potential. The implications of these findings are profound, suggesting that these Schiff base derivatives not only offer a new vantage point for the inhibition of BXO but also hold considerable promise as innovative therapeutic agents in the management and treatment of gout, marking a significant leap forward in the quest for more effective gout interventions.
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Pistacia Atlantica in folk medicine is used by Algerian traditional healers for treating a wide variety of diseases and conditions including dyspepsia, digestive problems, peptic ulcers, and, in particular, inflammatory diseases. The present study aimed to assess the phytochemical composition, in vitro antioxidant activity (using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ABTS+, and reducing power methods), enzyme inhibitory activity (towards α-amylase and urease), antibacterial activity, and in vivo anti-inflammatory activity of the unripe fruit extracts of Pistacia atlantica collected from different parts of the Djelfa region of Algeria. According to the findings, various aqueous extracts exhibited significant antioxidant and enzymatic activities in all tests, but showed that they have a weak inhibitory effect against all tested bacterial strains. Twenty-one minerals comprising both macro- and microelements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U, and Zn) were determined using the technique of neutron activation analysis (INAA). The result indicates that the concentration of the mineral element is close to the minimal FAO recommendation. In addition, the result revealed significant anti-inflammatory activities. The data generated can be a valuable source of information for the pharmaceutical industry and medical research. These results suggest that the unripe fruit extracts of Pistacia atlantica have an appropriate potential to be utilized across a wide range of contexts as an agent with multifunctional uses, as well as a natural remedy for other physiological diseases.
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Antioxidantes , Pistacia , Antioxidantes/farmacología , Antioxidantes/análisis , Pistacia/química , Ureasa , Extractos Vegetales/química , Frutas/química , Antibacterianos/farmacología , Antibacterianos/análisis , Minerales/análisis , Antiinflamatorios/farmacología , Antiinflamatorios/análisis , AmilasasRESUMEN
Fenugreek (Trigonella foenum-graecum) has a great beneficial health effect; it has been used in traditional medicine by many cultures. Likewise, the α-amylase inhibitors are potential compounds in the development of drugs for the treatment of diabetes. The beneficial health effects of fenugreek lead us to explore the chemical composition of the seeds and their antioxidant and α-amylase inhibition activities. The flavonoid extraction from fenugreek seeds was achieved with methanol through a Soxhlet apparatus. Then, the flavonoid glycosides were characterized using HPLC-DAD-ESI-MS analysis. The antioxidant capacity of fenugreek seed was measured using DPPH, FRAP, ABTS, and CUPRAC assays. Finally, the α-amylase inhibition activity was carried out using in vitro and in silico methods. The methanolic extract was found to contain high amounts of total phenolics (154.68 ± 1.50 µg GAE/mg E), flavonoids (37.69 ± 0.73 µg QE/mg E). The highest radical-scavenging ability was recorded for the methanolic extract against DPPH (IC50 = 556.6 ± 9.87 µg/mL), ABTS (IC50 = 593.62 ± 9.35 µg/mL). The ME had the best reducing power according to the CUPRAC (A 0.5 = 451.90 ± 9.07 µg/mL). The results indicate that the methanolic extracts of fenugreek seed best α-amylase inhibition activities IC50 = 653.52 ± 3.24 µg/mL. Twenty-seven flavonoids were detected, and all studied flavonoids selected have good affinity and stabilize very well in the pocket of α-amylase. The interactions between the studied flavonoids with α-amylase were investigated. The flavonoids from fenugreek seed present a good inhibitory effect against α-amylase, which is beneficial for the prevention of diabetes and its complications.
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Diabetes Mellitus , Trigonella , Humanos , Antioxidantes/química , Trigonella/química , Flavonoides/farmacología , Flavonoides/análisis , Simulación del Acoplamiento Molecular , alfa-Amilasas , Cromatografía Líquida de Alta Presión , Extractos Vegetales/química , Metanol/química , Semillas/químicaRESUMEN
After a lull of >20 years, Algeria experienced a cholera outbreak in 2018 that included 291 suspected cases. We found that outbreak isolates were Vibrio cholerae O1 serotype Ogawa from seventh pandemic El Tor sublineage AFR14, which corresponds to a new introduction of cholera into Africa from South Asia.
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Cólera , Vibrio cholerae O1 , Argelia/epidemiología , Cólera/epidemiología , Brotes de Enfermedades , Humanos , Pandemias , Vibrio cholerae O1/genéticaRESUMEN
The two important targets to treat gout disease are (1) control the hyperuricemia by the inhibition of Xanthine Oxidase (XO) and (2) treatment of acute attacks of gout by the use of anti-inflammatory drugs. It is important to distinguish between therapy to manage hyperuricemia and to reduce acute inflammation. While reducing hyperuricemia is resolved very slowly with available drugs, gout symptoms like pain and inflammation may become persistent. The objective of this study is to find a relevant treatment with a beneficial double effect. (1) As an anti-inflammatory, analgesic, and antipyretic effect and (2) as XO inhibitory effect, which is the main objective of this study. We investigated the effect of five non-steroidal anti-inflammatory drugs (NSAIDs) against human and bovine milk xanthine oxidases (HXO and BXO) using the double enzyme detection method (DED) and molecular docking with the Autodock vina program. in vitro results show that the NSAIDs give an important inhibition to HXO and BXO with an IC50 of 2.04 ± 0.13 µg/ml, 2.75 ± 0.23 µg/ml, 1.45 ± 0.19 µg/ml, 0.31 ± 0.13 µg/ml and 1.27 ± 0.11 µg/ml, for HXO, and 2.96 ± 0.27 µg/ml, 9.46 ± 0.13 µg/ml, 6.21 ± 1.17 µg/ml, 0.83 ± 0.11 µg/ml, and 3.48 ± 0.13 µg/ml, for BXO, for respectively, Naproxen, Ibuprofen, Diclofenac, Indomethacin, and Celecoxib. Testing the inhibitory activity of these drugs on both XOs shows an important inhibition, especially from Indomethacin, which could be a promising lead compound for reducing acute inflammation and at the same time controlling hyperuricemia.
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Inhibidores Enzimáticos , Xantina Oxidasa , Antiinflamatorios/farmacología , Inhibidores Enzimáticos/farmacología , Humanos , Simulación del Acoplamiento Molecular , Extractos VegetalesRESUMEN
Alkaloids and phenols are potent inhibitors family for many enzymes used in many therapies. We aim to evaluate in vitro and in silico, the inhibition effect of Hispidin, Harmaline, and Harmine as pure molecules to bovine milk xanthine oxidase (BXO), Molecular docking and SAR study with GOLD was done to explain the mechanism of action related to its inhibition, ADMET parameters were checked to confirm their pharmacokinetics (PK) using preADMET 2.0 server, we classified our inhibitors by applying five drug-likeness rules, the best-ranked inhibitors were chosen based on the approved ADMET properties, drug-likeness qualifications, and the best PLPchem score generated by GOLD. The in vitro results show important inhibition activity to BXO comparing to the control with an IC50 of 39.72 ± 3.60 µM, 51.00 ± 1.0 µM, and 48.52 ± 1.76 µM for Hispidin, Harmaline, and Harmine respectively. The in silico results show that Hispidin was the best inhibitor model with approved ADMET properties and qualification in all drug-likeness rules; Harmaline was saved second-best model to BXO with suitable ADMET properties and qualified in most drug-likeness rules. Eventually, Harmine was ranked third potent inhibitor model with acceptable ADMET properties, drug-likeness rules, and PLPchem score. The tested inhibitors could be significant in drug discovery, especially in treating gout disease; therefore, drug development, including clinical trials, should be done with promising results.
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Inhibidores Enzimáticos/farmacología , Harmalina/farmacología , Harmina/farmacología , Pironas/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Animales , Bovinos , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Harmalina/química , Harmina/química , Simulación del Acoplamiento Molecular , Estructura Molecular , Pironas/química , Relación Estructura-Actividad , Xantina Oxidasa/metabolismoRESUMEN
Polyphenolic and Terpenoids are potent natural antiparasitic compounds. This study aimed to identify new drug against Leishmania parasites, leishmaniasis's causal agent. A new in silico analysis was accomplished using molecular docking, with the Autodock vina program, to find the binding affinity of two important phytochemical compounds, Masticadienonic acid and the 3-Methoxycarpachromene, towards the trypanothione reductase as target drugs, responsible for the defense mechanism against oxidative stress and virulence of these parasites. There were exciting and new positive results: the molecular docking results show as elective binding profile for ligands inside the active site of this crucial enzyme. The ADMET study suggests that the 3-Methoxycarpachromene has the highest probability of human intestinal absorption. Through this work, 3-Methoxycarpachromene and Masticadienonic acid are shown to be potentially significant in drug discovery, especially in treating leishmaniasis. Hence, drug development should be completed with promising results.
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Leishmania infantum/enzimología , NADH NADPH Oxidorreductasas/antagonistas & inhibidores , Fitoquímicos/farmacología , Triterpenos/farmacología , Dominio Catalítico/efectos de los fármacos , Simulación por Computador , Evaluación Preclínica de Medicamentos , Humanos , Absorción Intestinal , Leishmania infantum/efectos de los fármacos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Fitoquímicos/química , Fitoquímicos/farmacocinética , Proteínas Protozoarias/antagonistas & inhibidores , Relación Estructura-Actividad , Triterpenos/química , Triterpenos/farmacocinéticaRESUMEN
This paper makes the first comparative assessment of the impacts of the first and second waves of the ongoing COVID-19 pandemic for the US stock market and its uncertainty. To this end, we investigate the dynamic conditional correlation and the asymmetric impacts of shocks on the correlation between the US and Chinese stock markets before and during the COVID-19 crisis. Furthermore, we analyze and compare the relationship between the COVID-19 pandemic and US returns and uncertainty during the first and second waves of the pandemic. First, we find that the dynamic correlation approach supports the presence of volatility spillovers (contagion effects) between the two stock markets, especially during the rapid spread phase of COVID-19 in the US. Second, the analysis of news impact correlation surfaces shows that the shocks to the US and Chinese markets have asymmetric effects on the correlation between the two markets. Finally, we find a persistent link between US returns, uncertainty, and the COVID-19 pandemic during the first and second waves of the outbreak. Our results prove that the pandemic has shown harmful consequences for financial markets in general and the US economy in particular.
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The current study investigated the effect of developmental stages on the chemical composition and the antioxidant activity of fifteen crude oil samples obtained from Pistacia atlantica Desf. leaves, galls, and fruits. Twelve fatty acids were detected by GC/FID, linolenic acid (C18 : 3) was the major fatty acid detected in leaves crude oils that registered [41.73 % (P<0.05)] on the last stage. The best content of tocopherols and carotenoids was recorded at the last stage for leaves and galls oils, respectively, with values of [1.530±0.01, 0.52±0.01 (P<0.05)â mg α-tocopherol equivalent/g DW] and [86.60±0.95, 69.15±0.13 (P<0.05)â µg ß-carotene equivalent/g DW]. For fruits oils, the content varied depending on the levels of fruits maturation. The results from DPPH, FRAP, and ABTS assays revealed that the antioxidant activity increased with the increasing content of tocopherols and carotenoids in leaves and galls oils during development stages, and varied for fruits oils depending on the ripening stages. Moreover, according to PCA analysis, the best phytoconstituent content and antioxidant activity were attributed to P. atlantica Desf. fruit's crude oils. Also, a strong relationship was found between the antioxidant activity and bioactive phytochemical components, such as tocopherols, carotenoids, and omega-three fatty acid, which confirmed that P. atlantica Desf. crude oils present a valuable source of natural antioxidant that could be used for pharmaceutical and food industries purposes.
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Antioxidantes/farmacología , Carotenoides/farmacología , Ácidos Grasos/farmacología , Petróleo/análisis , Pistacia/química , Tocoferoles/farmacología , Antioxidantes/química , Benzotiazoles/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Carotenoides/química , Ácidos Grasos/química , Recuperación de Fluorescencia tras Fotoblanqueo , Frutas/química , Picratos/antagonistas & inhibidores , Hojas de la Planta/química , Ácidos Sulfónicos/antagonistas & inhibidores , Tocoferoles/químicaRESUMEN
The widespread use of Deverra scoparia Coss. & Durieu in Algerian folk-medicine as a remedy can be relatively attributed to its total phenolic compounds. The current study aimed to provide a scientific basis for optimal collection and usage of Deverra scoparia Coss. & Durieu plant. Hence, 37 samples were gathered from nine sites in Algeria during two seasons 2016 and 2017, then exposed to a green extraction. Total phenolic (TPC), flavonoid (FC) and condensed tannins (CTC) content were estimated spectrophotometrically. The antioxidant activity was measured using five different methods, DPPH. , ABTS.+ , FRAP, CUPRAC and Fe2+ -chelating. The results have revealed considerable amounts of TPC varied from 804 to 1544â mg GAE/100â g dry matter, FC started from 187 up to 410â mg QE/100â g dry matter and CTC varied from 111 to 394â mg CE/100â g dry matter. The best IC50 values (µg/mL) of DPPH. , ABTSâ¢+ , FRAP, CUPRAC and Fe2+ -chelating tests were 56.62, 5.41, 21.26, 52.93 and 78.10, respectively. Moreover, high correlations were found between CTC and most of the antioxidant tests. Hence, CTC are suggested to be the principal group of antioxidant activity in Deverra scoparia Coss. & Durieu extracts.
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Antioxidantes/análisis , Flores/química , Metanol/química , Fenoles/análisis , Extractos Vegetales/análisis , Semillas/química , Argelia , Antioxidantes/farmacología , Benzotiazoles/antagonistas & inhibidores , Compuestos de Bifenilo/antagonistas & inhibidores , Cobre/química , Quelantes del Hierro/química , Fenoles/farmacología , Picratos/antagonistas & inhibidores , Extractos Vegetales/farmacología , Análisis de Componente Principal , Estaciones del Año , Ácidos Sulfónicos/antagonistas & inhibidoresRESUMEN
For the first time, the enzymatic inhibition activity of 13 synthetic flavonoids was assessed by quantitative structure-activity relationship (QSAR) modeling and molecular docking with the three states of the enzyme horseradish peroxidase (HRP). The results show that apigenin, quercetin, kaempferol, fisetin, tricetin, and luteolin exerted a high competitive inhibition on HRP (Ki between 0.14 and 1.74 mM) compared with other flavonoids. The QSAR model of enzymatic activity (R2 = 0.95, RMSE = 5.48) showed that Ghose-Crippen octanol-water partition coefficient (Alog P) and lowest unoccupied molecular orbital's energy (εlumo ) correlated with 0.65 and 0.17, respectively, with Ki values. According to the docking results using Molegro Virtual Docker program, all the flavonoids have shown great binding affinity towards peroxidase. Apigenin has the largest MolDock score in the three states of HRP noting an increased affinity of these flavonoids between compound I and compound II by 2.26%. However, these affinities strongly decrease between compound II and compound III by 28.43% especially for luteolin whose MolDock score decreased by 74.7%. With the results of docking, the affinities of the flavonoids tested and translated by their Ki values are much more presentative of the inhibition of the first reaction states of HRP because their inhibitory effect is important.
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Antioxidantes/farmacología , Inhibidores Enzimáticos/farmacología , Flavonoides/química , Flavonoides/farmacología , Peroxidasa de Rábano Silvestre/antagonistas & inhibidores , Isoenzimas/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad Cuantitativa , Antioxidantes/química , Inhibidores Enzimáticos/química , Flavonoides/metabolismo , Peroxidasa de Rábano Silvestre/metabolismo , Isoenzimas/metabolismo , Unión ProteicaRESUMEN
The antifungal potency of the essential oils of Rhanterium adpressum was evaluated against four mycotoxigenic strains of the genus Fusarium. The essential oils were obtained, separately, by hydro-distillation of the aerial parts of R. adpressum (leaves and flowers). The parts were collected during the period of bloom (3 months) for 3 years. The GC-MS analysis revealed thirty-six compounds for the essential oils, divided into four classes of chemical compounds, with variable percentages according to the month of extraction. The monoterpene hydrocarbons form the main class in these oils. On the other hand, the highest percentages of the oxygenated compounds are observed in the samples collected during the month of May. The direct contact method was used to evaluate the antifungal activity of the essential oils. The activity can be attributed to their relatively high composition of oxygenated monoterpenes. Flowers extract showed strong inhibitory activity, with very interesting concentrations of IC50 and MIC for both tests on solid and liquid medium. The effect of these oils on the production of type B trichothecenes (TCTBs) was evaluated, showing a significant inhibitory effect on TCTBs production, for both extracts (leaves and flowers). The rates of inhibition were 66-97 and 76-100% of FX, 3-ADON and 15-ADON, respectively. The inhibition of fungal biomass and the production of TCTBs depended on the used concentration of the essential oils. These results suggest that the essential oils from R. adpressum are able to control the growth of the tested strains and their subsequent production of TCTB mycotoxins.
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Antifúngicos/farmacología , Asteraceae/metabolismo , Fusarium/efectos de los fármacos , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Flores/metabolismo , Fusarium/clasificación , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Monoterpenos/farmacología , Micotoxinas/biosíntesis , Hojas de la Planta/metabolismo , Tricotecenos/biosíntesisRESUMEN
For the first time, the structure-activity relationships of thirteen synthesized flavonoids have been investigated by evaluating their ability to modulate horseradish peroxidase (HRP) catalytic activity. Indeed, a modified spectrophotometrically method was carried out and optimized using 4-methylcatechol (4-MC) as peroxidase co-substrate. The results show that these flavonoids exhibit a great capacity to inhibit peroxidase with Ki values ranged from 0.14±0.01 to 65±0.04mM. Molecular docking has been achieved using Auto Dock Vina program to discuss the nature of interactions and the mechanism of inhibition. According to the docking results, all the flavonoids have shown great binding affinity to peroxidase. These molecular modeling studies suggested that pyran-4-one cycle acts as an inhibition key for peroxidase. Therefore, potent peroxidase inhibitors are flavonoids with these structural requirements: the presence of the hydroxyl (OH) group in 7, 5 and 4' positions and the absence of the methoxy (O-CH3) group. Apigenin contributed better in HRP inhibitory activity. The present study has shown that the studied flavonoids could be promising HRP inhibitors, which can help in developing new molecules to control thyroid diseases.
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Antioxidantes/farmacología , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Peroxidasa de Rábano Silvestre/antagonistas & inhibidores , Simulación del Acoplamiento Molecular , Antioxidantes/síntesis química , Antioxidantes/química , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Flavonoides/síntesis química , Flavonoides/química , Peroxidasa de Rábano Silvestre/metabolismo , Estructura Molecular , Relación Estructura-ActividadRESUMEN
CONTEXT: The widespread use of Pistacia atlantica Desf. ssp. (Anacardiaceae) in traditional medicine can be partly attributed to the content of its secondary metabolites, in particular, the phenolic compounds. OBJECTIVE: The effects of harvest period, growing region and gender on the phenolic compounds, flavonoids and condensed tannins contents were studied, as well as on the antioxidant activities of P. atlantica leaves in order to provide a scientific basis for optimal collection. MATERIALS AND METHODS: Leaves were collected monthly from April to October 2010 in two Algerian sites. The powdered leaves were used for preparing the ethyl acetate extract. Contents of total phenolics (TPC), flavonoids (FC) and condensed tannins (CTC) were determined spectrophotometrically. Antioxidant activity was evaluated through radical scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (250 µM) and the reducing power capacity (RPC) determination by K3Fe(CN)6 (1%). RESULTS: The TPC was found to vary from 79 ± 13 to 259 ± 8 mg gallic acid equivalents/g of dry weight (DW) during the study period. The RSA and RPC varied between 262 ± 18 and 675 ± 21 mg Ascorbic Acid Equivalent (AAE)/g DW, and from 259 ± 16 to 983 ± 20 mg AAE/g DW, respectively. A seasonal pattern was observed consisting of a decrease in TPC content and RPC from spring to autumn. The FC, CTC and RSA did not show a seasonal pattern. DISCUSSION AND CONCLUSION: Our findings showed that secondary metabolite content and antioxidant activities of P. atlantica leaves were more influenced by harvest time and growing region than by gender.
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Antioxidantes/análisis , Flavonoides/análisis , Fenoles/análisis , Pistacia , Extractos Vegetales/análisis , Estaciones del Año , Taninos/análisis , Hojas de la Planta , Factores SexualesRESUMEN
The inhibitory effect of phenolic compounds and alkaloids of Inonotus hispidus and Peganum harmala on Candida rugosa lipase was investigated, also, their antioxidant activities using DPPH, ABTS and phosphomolybdenum were studied in this paper. The phenolic extracts have shown a stronger antiradical activity than the alkaloids extracts. The enzymatic inhibition produced by these extracts is described here for the first time. The results have shown that the phenolic and the alkaloid extracts are good inhibitors of C. rugosa lipase. Thus, the inhibitor molecules (harmaline and hispidin) have been isolated from P. harmala and I. hispidus. Their structures were elucidated by (1)H NMR analysis. Molecular docking has been achieved using AutoDock Vina program to discuss the nature of interactions and the mechanism of inhibition. Therefore, these isolated molecules could be used in the treatment of candidiasis.
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Inhibidores Enzimáticos/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Harmalina/farmacología , Lipasa/antagonistas & inhibidores , Pironas/farmacología , Antioxidantes/farmacología , Basidiomycota , Candida , Harmalina/aislamiento & purificación , Harmina/aislamiento & purificación , Lactonas/farmacología , Simulación del Acoplamiento Molecular , Orlistat , Peganum , Pironas/aislamiento & purificaciónRESUMEN
The global financial markets suffered unprecedented shocks, leading to significantly increased uncertainty in the markets due to various economic and financial recessions and geopolitical tensions, resulting in substantial fluctuations in market prices. Therefore, this paper aims to identify the response of the clean energy, conventional energy, and food markets to economic uncertainty and political tension while considering the influence of numerous crises and political conflicts. To achieve this, we employ the DCC-GARCH-based connectedness approach and the quantile-on-quantile model on monthly data spanning from May 2008 to June 2023. The results provide evidence of the sensitivity of dynamic volatility spillovers between financial assets to GEPU and GPR during major economic and financial crises and geopolitical events. Notably, this sensitivity increases significantly during the global financial crisis (GFC), the European debt crisis, Brexit, the US presidential election, the COVID-19 pandemic, and the Russian-Ukrainian war. However, the investigation of the tail dependence structure reveals that the relationship between uncertainties and total volatility connectedness across various market conditions appears to be asymmetric and heterogeneous. Our findings assist policymakers and green investors in designing the most effective policies to mitigate the impact of uncertainties on both conventional and green investments. This is achieved through insightful knowledge about the primary drivers of contagion among these indices, all while not compromising sustainability goals.
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Inversiones en Salud , Pandemias , Humanos , Unión Europea , Incertidumbre , Reino UnidoRESUMEN
Poly(L-Lactide) (PLA), a fully biobased aliphatic polyester, has attracted significant attention in the last decade due to its exceptional set of properties, such as high tensile modulus/strength, biocompatibility, (bio)degradability in various media, easy recyclability and good melt-state processability by the conventional processes of the plastic/textile industry. Blending PLA with other polymers represents one of the most cost-effective and efficient approaches to develop a next-generation of PLA-based materials with superior properties. In particular, intensive research has been carried out on PLA-based blends with engineering polymers such as polycarbonate (PC), poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT) and various polyamides (PA). This overview, consequently, aims to gather recent works over the last 10 years on these immiscible PLA-based blends processed by melt extrusion, such as twin screw compounding. Furthermore, for a better scientific understanding of various ultimate properties, processing by internal mixers has also been ventured. A specific emphasis on blend morphologies, compatibilization strategies and final (thermo)mechanical properties (tensile/impact strength, ductility and heat deflection temperature) for potential durable and high-performance applications, such as electronic parts (3C parts, electronic cases) to replace PC/ABS blends, has been made.
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This study explores the synergistic antibacterial effects of essential oils (EOs) and phenolic extracts from three plants against foodborne pathogenic bacteria. The present work aimed to investigate the synergistic effects of the binary and the ternary combinations of extracts using different blend proportions of the following plant extracts: Artemisia campestris (AC), Artemisia herba alba (AHA), and Citrus aurantium (CA). The antimicrobial activities of EOs and phenolic extracts were determined and evaluated against five strains. For the EOs, the results of the DIZ showed the existence of synergism for different combinations of binary blends, such as AC/AHA or AHA/CA against Escherichia coli, and AC/CA against Enterobacter faecalis. In addition, ternary blends of AC:AHA:CA at a ratio of 1/6:2/3:1/6 exhibited a synergy effect, as measured by the CI, against E. coli. On the other hand, for the phenolic extracts, synergistic effects were noticed for binary blends of AC/CA at different ratios against E. coli, E. faecalis, and Pseudomonas aeruginosa strains. Similarly, ternary blends of phenolic extracts presented synergy against E. coli, E. faecalis, P. aeruginosa strains, and even C. albicans. In this case, the blending ratios were crucial determining factors for maximizing the synergy effect. The study established that the proportion of a single drug could play an essential role in determining the bioefficacy of a drug combination treatment. Therefore, the results showed the importance of studying the modulation of antibacterial activities based on the proportions of extracts in the mixture and finding the range of proportions (as determined by SLMD) that have a synergistic/additive/antagonistic effect with no or low side effects, which can be used in a food preservation system.
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Artemisia , Citrus , Aceites Volátiles , Aceites Volátiles/farmacología , Escherichia coli , Antibacterianos/farmacología , Fenoles/farmacologíaRESUMEN
Antibiotics have become increasingly ineffective in the face of bacterial resistance, particularly in hospitals. Interestingly, there is high demand for bioprospecting of secondary metabolites, particularly for treating multidrug-resistant clinical diseases. In fact, Rosemary has been used for its antiseptic properties dating back to antiquity. The aim of this research is to evaluate the effectiveness of Rosmarinus officinalis essential oil against multidrug-resistant clinical bacterial pathogens. Results showed promising antibacterial activity against seven bacteria: Escherichia coli, Enterobacter cloacae, Staphylococcus aureus, Serratia odorifera, Klebsiella pneumoniae, Klebsiella oxytoca, Aeromonas hydrophila with MIC values of 35.7, 17.85, 71.4, 8.9, 17.8, 285.7, 35.7 µg/ml respectively and MBC values of 142.8, 71.4, 285.7, 35.7, 71.4, 571.5,71.4 µg/ml respectively. This study suggests that Rosmarinus essential oil can be used as a therapeutic agent in the fight against a wide range of multi-resistant bacteria.
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Aceites Volátiles , Rosmarinus , beta-Lactamasas/metabolismo , Aceites Volátiles/farmacología , Antibacterianos/farmacología , Bacterias , Escherichia coli , Pruebas de Sensibilidad MicrobianaRESUMEN
This study aimed to evaluate the potential therapeutic effects of Phillyrea angustifolia L leaves and fruits from Algeria. The total phenolic and flavonoid contents, sun protection factor, antimicrobial, antifungal, and antioxidant activities such as DPPH, ABTS, FRAP, CUPRAC, and o-phenanthroline reduction were determined. The findings of the comparative analysis revealed that the leaves contained higher levels of total phenolic content (TPC) and flavonoid content (TFC) compared to the fruit, indicating their maximum antioxidant potential. TPC values for leaves ranged from 528.411 ± 9.94 to 816.352 ± 5.09 µg EAG/mg of dry extract, while for fruits, it ranged from 378.215 ± 5.26 to 579.392 ± 14.2 µg EAG/mg extract/ml. Similarly, TFC values for leaves varied from 65.833 ± 9.42 to 147.986 ± 5.59 µg EAG/mg of dry extract, and for fruits, it ranged from 45.486 ± 5.00 to 90.208 ± 6.77 µg EAG/mg extract/ml. Moreover, both leaves and fruit extracts showed significant growth inhibition against Staphylococcus aureus and Enterococcus faecalis, with the highest activity against Staphylococcus aureus, followed by Escherichia coli. The sun protection factor (SPF) values of both leaves and fruits extracts are close to the values of standard sunscreen VICHY. In addition, molecular docking studies identified promising compounds, including Demethyloleuropein, Luteolin-7-O-glucoside, Apigenin 7-Glucoside, Oleuropein, Pinoresinol, and Syringaresinol monoglucopyranoside of leaves from P. angustifolia L, these compounds are showing a better binding affinity than native ligands against Rhomboid protease GlpG from E. coli, the same thing about luteolin-7-O-glucoside and apigenin 7-glucoside exhibited similar binding free energy values to the target protein S. aureus sortase A. The study suggests that leaves and fruits of Phillyrea angustifolia L could be valuable sources for developing drugs against pathogenic oral yeasts, Gram-negative and Gram-positive bacteria. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03877-5.