Mesosphaerum suaveolens (Lamiacae): Source of antimicrobial and antioxidant compounds

The use in folk medicine of leaves of Mesosphaerum suaveolens for the treatment of diseases of the digestive system and respiratory system, raised the hypothesis that its volatile oil has biological properties against pathogenic microorganisms. To evaluate this hypothesis, the antibacterial, antifungal activity against Candida yeast strains, which modifies the action of antibiotics and antioxidants (DPPH) was evaluated in vitro. In addition, it was determined by means of Gas Chromatography (GC-FID), the constituents present in the essential oil. The results show that M. suaveolens oil has antibacterial activity against standard and multidrug-resistant strains of Staphylococcus aureus, with a MIC of 64 and 256 μg/mL respectively, however it does not have the capacity to enhance the action of commercial antibacterials. Regarding the anti-Candida activity, it was possible to observe that there was biological action, since they presented IC50 de 18.15 µg/mL for Candida albicans URM and 40.4 for Candida tropicalis INCQS 40042. In addition, the oil was able to modulate fluconazole for all strains analyzed. As for the antioxidant action, the oil demonstrated that even in low percentages, there is an action in the reduction of free radicals (IC50> 200 µg/mL). Such activities may be related to the major constituent of the oil, the sesquiterpene β-caryophyllene (C17H28O2). Thus, M. suaveolens oil is a natural source with antimicrobial and antioxidant properties.

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Resazurin Method for Evaluation of Bioactive Compounds from Cranberry Extracts Using the Metabolic Activity of a ΔSOD1 Mutant of Saccharomyces cerevisiae Yeast Under Severe Osmotic Stress

Journal of AOAC International ◽

10.5740/jaoacint.19-0264 ◽

2020 ◽

Vol 103 (2) ◽

pp. 422-427

Author(s):

Agata Święciło ◽

Kamila Rybczyńska-Tkaczyk

Keyword(s):

Saccharomyces Cerevisiae ◽

Growth Parameters ◽

Raw Materials ◽

Antioxidant Properties ◽

Biological Properties ◽

Biologically Active ◽

Antioxidant Compounds ◽

Alcohol Water

Abstract Background: In addition to nutrients, plant raw materials for food production should also contain substances with beneficial biological properties, which unquestionably include antioxidant compounds. Among the numerous methods of determining the antioxidant properties of samples of plant material, biological methods that provide information about not only the in vivo antioxidant potential of samples but also their metabolism and bioavailability are increasingly valued. Objective: The aim of the study was to assess the antioxidant properties of extracts from large cranberry (Vaccinium macrocarpon) obtained from different producers. Methods: Biologically active compounds were extracted from cranberry fruits using water alone and ethyl alcohol–water in proportions of 1+1 and 4+1 (v/v) as solvents. The following were determined in the extracts: content of phenolic compounds and anthocyanins, total antioxidant capacity based on reduction of the ABTS+• [2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] radical cation, and antioxidant properties as reflected by the growth of a Saccharomyces cerevisiae Δsod1 mutant in a liquid hypertonic environment. The growth parameters of this Δsod1 mutant, monitored by a method exploiting a color reaction with resazurin, reflected the antioxidant properties of the extracts. Results: The ethanol–water cranberry extracts showed higher content of polyphenols, anthocyanins, and total antioxidants expressed as Trolox equivalent, determined on the basis of ABTS+• reduction. Conclusions: The antioxidant properties determined by the bioassay did not respond strongly to the data obtained in the in vitro chemical and biochemical assays, because they were more closely associated with the batch of fruit than with the type of solvent used to extract phytochemicals.

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Antibacterial Action of Curcumin against Staphylococcus aureus: A Brief Review

Journal of Tropical Medicine ◽

10.1155/2016/2853045 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 76

Author(s):

Sin-Yeang Teow ◽

Kitson Liew ◽

Syed A. Ali ◽

Alan Soo-Beng Khoo ◽

Suat-Cheng Peh

Keyword(s):

Staphylococcus Aureus ◽

Antibacterial Agents ◽

Curcuma Longa ◽

Antibacterial Activities ◽

Multidrug Resistant ◽

Major Constituent ◽

Global Health Issue ◽

Resistant Strains ◽

Urgent Action

Curcumin, the major constituent of Curcuma longa L. (Zingiberaceae family) or turmeric, commonly used for cooking in Asian cuisine, is known to possess a broad range of pharmacological properties at relatively nontoxic doses. Curcumin is found to be effective against Staphylococcus aureus (S. aureus). As demonstrated by in vitro experiment, curcumin exerts even more potent effects when used in combination with various other antibacterial agents. Hence, curcumin which is a natural product derived from plant is believed to have profound medicinal benefits and could be potentially developed into a naturally derived antibiotic in the future. However, there are several noteworthy challenges in the development of curcumin as a medicine. S. aureus infections, particularly those caused by the multidrug-resistant strains, have emerged as a global health issue and urgent action is needed. This review focuses on the antibacterial activities of curcumin against both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). We also attempt to highlight the potential challenges in the effort of developing curcumin into a therapeutic antibacterial agent.

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1280. In-Vitro Activity of Cefiderocol, Imipenem/Relebactam, & Ceftazidime/Avibactam in Ceftolozane/Tazobactam Resistant Strains of Multidrug Resistant Pseudomonas aeruginosa

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1463 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S655-S655

Author(s):

Daniel Navas ◽

Angela Charles ◽

Amy Carr ◽

Jose Alexander

Keyword(s):

Multidrug Resistant ◽

Resistance Mechanisms ◽

Vitro Activity ◽

Clinical Isolates ◽

Resistance Testing ◽

Clinical Samples ◽

In Vitro Activity ◽

Carbapenemase Gene ◽

Resistant Strains

Abstract Background The activity of imipenem/relebactam (I/R), ceftazidime/avibactam (CZA) and cefiderocol (FDC) were evaluated against clinical isolates of multidrug resistant (MDR) strains of P. aeruginosa which was resistant to ceftolozane/tazobactam (C/T). The recent increase of MDR P. aeruginosa strains isolated from clinical samples has prompted research and development of new antimicrobials that can withstand its multiple resistance mechanisms. C/T is an effective option for treatment of MDR P. aeruginosa in our facility with only 10% of resistance in MDR strains, but the emergence of resistance may occur due to the presence of a carbapenemase gene or an ampC mutation. Methods Antimicrobial susceptibility testing for C/T Etest® (bioMérieux, Inc.) were performed on all MDR strains initially screened by the VITEK2® (bioMérieux, Inc.). 10% (n=20) of all MDR isolates were resistant to C/T by the CLSI 2019 breakpoints. These resistant isolates were tested for presence of a carbapenemase gene using the GeneXpert CARBA-R (Cepheid®) PCR and against CZA Etest® (bioMérieux, Inc.) I/R gradient strips (Liofilchem®) and FDC broth microdilution (Thermo Scientific™ Sensititre™). Results A total of 20 clinical isolates of MDR P. aeruginosa resistant to C/T were tested following standardized CLSI protocols and techniques. All 20 isolates were screened for the presence of a carbapenemase gene (blaVIM, blaNDM, blaKPC, blaOXA-48, blaIMP). A blaVIM gene was detected in 6 (30%) out of 20 isolates. FDC demonstrated the greatest activity with 85% (n=17) of susceptible isolates (CLSI MIC <4µg/dL). CZA (CLSI MIC <8µg/dL) and I/R (FDA MIC <2µg/dL) showed 15% (n=3) and 10% (n=2) of susceptible isolates respectively. FDC was active against all 6 blaVIM isolates, where all 6 strains were resistant to CZA and I/R as expected. 3 isolates tested non-susceptible against FDC; additional characterization was not performed at this time. Conclusion Based on these results, FDC demonstrated the greatest in-vitro activity against C/T resistant strains of MDR P. aeruginosa. FDC also demonstrated activity against all 6 MDR P. aeruginosa carrying blaVIM gene. FDC is a strong option to consider on MDR P. aeruginosa strains based on a resistance testing algorithm and a cost/effective protocol. Disclosures All Authors: No reported disclosures

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Isobornylchalcones as Scaffold for the Synthesis of Diarylpyrazolines with Antioxidant Activity

Molecules ◽

10.3390/molecules26123579 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3579

Author(s):

Svetlana A. Popova ◽

Evgenia V. Pavlova ◽

Oksana G. Shevchenko ◽

Irina Yu. Chukicheva ◽

Aleksandr V. Kutchin

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Biological Properties ◽

High Reactivity ◽

Biologically Active ◽

Brain Lipids ◽

Wide Range ◽

Privileged Structure ◽

Vitro Model

The pyrazoline ring is defined as a “privileged structure” in medicinal chemistry. A variety of pharmacological properties of pyrazolines is associated with the nature and position of various substituents, which is especially evident in diarylpyrazolines. Compounds with a chalcone fragment show a wide range of biological properties as well as high reactivity which is primarily due to the presence of an α, β-unsaturated carbonyl system. At the same time, bicyclic monoterpenoids deserve special attention as a source of a key structural block or as one of the pharmacophore components of biologically active molecules. A series of new diarylpyrazoline derivatives based on isobornylchalcones with different substitutes (MeO, Hal, NO2, N(Me)2) was synthesized. Antioxidant properties of the obtained compounds were comparatively evaluated using in vitro model Fe2+/ascorbate-initiated lipid peroxidation in the substrate containing brain lipids of laboratory mice. It was demonstrated that the combination of the electron-donating group in the para-position of ring B and OH-group in the ring A in the structure of chalcone fragment provides significant antioxidant activity of synthesized diarylpyrazoline derivatives.

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Silver Nanoparticles and Their Antibacterial Applications

International Journal of Molecular Sciences ◽

10.3390/ijms22137202 ◽

2021 ◽

Vol 22 (13) ◽

pp. 7202

Author(s):

Tamara Bruna ◽

Francisca Maldonado-Bravo ◽

Paul Jara ◽

Nelson Caro

Keyword(s):

Silver Nanoparticles ◽

Antibacterial Agents ◽

Multidrug Resistant ◽

Secondary Effects ◽

Cytotoxic Effects ◽

Factors Affecting ◽

Gram Positive Bacteria ◽

Resistant Strains

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.

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Preliminary Study on Pasta Samples Characterized in Antioxidant Compounds and Their Biological Activity on Kidney Cells

Nutrients ◽

10.3390/nu13041131 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1131 ◽

Cited By ~ 1

Author(s):

Federico Di Marco ◽

Francesco Trevisani ◽

Pamela Vignolini ◽

Silvia Urciuoli ◽

Andrea Salonia ◽

...

Keyword(s):

Indoleacetic Acid ◽

Antioxidant Properties ◽

Antioxidant Compounds ◽

Kidney Cells ◽

Hek 293 ◽

293 Cells ◽

High Concentrations ◽

Β Carotene ◽

Egg Pasta

Pasta is one of the basic foods of the Mediterranean diet and for this reason it was chosen for this study to evaluate its antioxidant properties. Three types of pasta were selected: buckwheat, rye and egg pasta. Qualitative–quantitative characterization analyses were carried out by HPLC-DAD to identify antioxidant compounds. The data showed the presence of carotenoids such as lutein and polyphenols such as indoleacetic acid, (carotenoids from 0.08 to 0.16 mg/100 g, polyphenols from 3.7 to 7.4 mg/100 g). To assess the effect of the detected metabolites, in vitro experimentation was carried out on kidney cells models: HEK-293 and MDCK. Standards of β-carotene, indoleacetic acid and caffeic acid, hydroalcoholic and carotenoid-enriched extracts from samples of pasta were tested in presence of antioxidant agent to determine viability variations. β-carotene and indoleacetic acid standards exerted a protective effect on HEK-293 cells while no effect was detected on MDCK. The concentrations tested are likely in the range of those reached in body after the consumption of a standard pasta meal. Carotenoid-enriched extracts and hydroalcoholic extracts showed different effects, observing rescues for rye pasta hydroalcoholic extract and buckwheat pasta carotenoid-enriched extract, while egg pasta showed milder dose depending effects assuming pro-oxidant behavior at high concentrations. The preliminary results suggest behaviors to be traced back to the whole phytocomplexes respect to single molecules and need further investigations.

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Extraction of Antioxidant Compounds from Blueberry Fruit Waste and Evaluation of Their In Vitro Biological Activity in Human Keratinocytes (HaCaT)

Food Analytical Methods ◽

10.1007/s12161-021-02056-7 ◽

2021 ◽

Author(s):

Tomasz Piechowiak ◽

Bartosz Skóra ◽

Katarzyna Grzelak-Błaszczyk ◽

Michał Sójka

Keyword(s):

Antioxidant Activity ◽

Antioxidant Properties ◽

Waste Material ◽

Lower Amount ◽

Process Time ◽

Antioxidant Compounds ◽

Mass Unit ◽

Diet Supplements ◽

Study Results

AbstractThe purpose of this study was to investigate the biological properties of an extract obtained from the waste of blueberry fruit. The study covered the optimization of extraction of antioxidants from blueberry pomace and the determination of antioxidant properties of the extract using HaCaT as the model organism. Research showed that the yield of antioxidants extraction from blueberry waste was dependent on the applied extraction conditions. Based on the mathematical models, the optimal conditions of extraction process in which the maximum quantity of antioxidant compounds is achieved from the waste mass unit, i.e., the relation of the waste mass to the volume of ethanol equal to 1:17.36, and process time equal to 1000 s. The obtained extract was characterized by high antioxidant activity, which was shaped by high content of polyphenols, mainly anthocyanins. Moreover, the extract showed a high ability to protect HaCaT cells from the occurrence of oxidative stress induced by H2O2. Cells treated with the extract and H2O2 generated a lower amount of ROS than cells treated with H2O2 only. The obtained results will be base of further studies on applying the extract in production of diet supplements and functional foods with increased antioxidant activity. Moreover, the main research material is blueberry pomace which is a troublesome waste material for juice producers. Consequently, according to a sustainable development idea, the study results will provide an opportunity to increase interest in the problem of rational use of the waste material to a certain extent.

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Studies on drying characteristic, nutritional composition, and antioxidant properties of Stevia rebaudiana (Bertoni) leaves

International Agrophysics ◽

10.1515/intag-2015-0039 ◽

2015 ◽

Vol 29 (3) ◽

pp. 323-331 ◽

Cited By ~ 7

Author(s):

Yolanda B. Moguel-Ordóñez ◽

Diana L. Cabrera-Amaro ◽

Maira R. Segura-Campos ◽

Jorge C. Ruiz-Ruiz

Keyword(s):

Antioxidant Properties ◽

Reducing Power ◽

Stevia Rebaudiana ◽

Biological Properties ◽

Nutritional Composition ◽

Antioxidant Compounds ◽

Drying Methods ◽

Stevia Rebaudiana Bertoni ◽

Trolox Equivalent ◽

Drying Treatment

Abstract Drying characteristics of Stevia rebaudiana (Bertoni) leaves using radiation drying, convection drying, sun drying, and shade drying treatments were investigated in a convective type. Results for all treatments indicated that drying took place in the falling rate period. The chroma of the dried samples ranged between 29.66 and 23.85. Convection and shade drying samples were found better in colour and had the highest content of total pigments. The proximate and fibre composition were affected by the drying treatments. Extracts obtained from convection drying and shade drying leaves exhibited higher values of Trolox equivalent antioxidant capacities 416.89-423.64 mM mg−1 and ferric reducing power 85.19-87.97%. These extracts also showed ion chelating capacity 59.05-60.21% for Cu+2 and 55.05-59.11% for Fe+2. The results indicate that it is possible to select the drying treatment to obtain the best nutritional and biological properties. Convection drying and shade drying were the least aggressive treatments and leaf powders obtained by these drying methods could be used as sources of nutrients, fibre, and antioxidant compounds.

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Comparative Evaluation of Onion Germplasm (Allium Cepa L.) Of Bangladesh for Physical And Antioxidant Properties

SAARC Journal of Agriculture ◽

10.3329/sja.v19i1.54783 ◽

2021 ◽

Vol 19 (1) ◽

pp. 113-123

Author(s):

PK Dash ◽

S Das ◽

MA Mannan ◽

M Jahan

Keyword(s):

Free Radicals ◽

Antioxidant Properties ◽

Biological Properties ◽

Physicochemical Analysis ◽

The Other ◽

Antioxidant Compounds ◽

Visual Methods ◽

Ic50 Value ◽

Onion Germplasm

Determination of antioxidant activity is one of the key elements for understanding the biological properties of a widely used spice onion (A. cepa). In contrast, physical properties help understand the textural quality of onion necessary for postharvest operations of sorting and grading in particular. Considering the physicochemical importance of onion, the present study focused on the determination of physical attributes and antioxidant content of the onion germplasm in Bangladesh using visual methods and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, respectively. The five-onion germplasms (BARI Piaz-2, BARI Piaz-3, BARI Piaz-4, BARI Piaz-5, Faridpuri Vati) collected from selected onion growers of the Department of Agricultural Extension (DAE) of the southwestern part of Bangladesh were used as treatments for physicochemical analysis at the Horticulture laboratory of the Agrotechnology Discipline, Khulna University, Khulna, Bangladesh during the period from February to August 2019. The laboratory study was laid out in Completely Randomized Design (CRD) with three replications. Most of the physical characteristics of onion were highest in germplasm-1 than those of the other germplasm tested. The results showed that the DPPH free radicals were scavenged by all onion germplasm extracts in a concentration-dependent pattern. The highest IC50 value (238.10 ppm) was noticed in germplasm-3 and the lowest in germplasm-5 (161.29 ppm) with no statistical difference from germplasm-4 (172.41 ppm). The lower IC50 value indicating that onion germplasms-5 and -4 extracts were more potent in scavenging free radicals than the other onion germplasms. Thus, the low IC50 value facilitated the germplasm-5 and -4 to be enriched with antioxidant compounds significantly in higher amounts than the others. SAARC J. Agric., 19(1): 113-123 (2021)

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In vivo and in vitro antiplasmodial activities of some plants traditionally used in Guatemala against malaria.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.41.7.1500 ◽

1997 ◽

Vol 41 (7) ◽

pp. 1500-1503 ◽

Cited By ~ 29

Author(s):

F F Franssen ◽

L J Smeijsters ◽

I Berger ◽

B E Medinilla Aldana

Keyword(s):

Plasmodium Berghei ◽

Brine Shrimp ◽

Folk Medicine ◽

Artemia Salina ◽

In Vitro Cultures ◽

Cytotoxic Effects ◽

Resistant Strains ◽

Simarouba Glauca

We present an evaluation of the antiplasmodial and cytotoxic effects of four plants commonly used in Guatemalan folk medicine against malaria. Methanol extracts of Simarouba glauca D. C., Sansevieria guineensis Willd, Croton guatemalensis Lotsy, and Neurolaena lobata (L.)R.Br. significantly reduced parasitemias in Plasmodium berghei-infected mice. Dichloromethane fractions were screened for their cytotoxicities on Artemia salina (brine shrimp) larvae, and 50% inhibitory concentrations were determined for Plasmodium falciparum in in vitro cultures. Both chloroquine-susceptible and -resistant strains of P. falciparum were significantly inhibited by these extracts. Of all dichloromethane extracts, only the S. glauca cortex extract was considered to be toxic to nauplii of A. salina in the brine shrimp test.

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