Genotoxicity evaluation in vitro by comet assay of compound and crude extract obtained from P. Pubescens Benth.

Plant-derived digestive enzyme inhibitors particularly those targeted to carbohydrate metabolism has been the focus of recent studies as natural supplements for weight control and diabetes. The present study explores the salivary amylase inhibition activity of Garcinia mangostana (Linn.) pericarp extracts and Carica papaya (Linn.) leaf extracts and fractions, as well as perform phytochemical screening and quantification, and thin layer – and high performance liquid chromatographic profiling. Results show that crude extracts and purified fractions were able to inhibit salivary amylase, with C. papaya fraction 1 being the most active at 30.89% inhibition. Phytochemical screening of all extracts tested positive for tannins, glycosides, phenolics, flavonoids and alkaloids. Quantification of phenolics showed that extracts contained high levels of phenolics, with C. papaya crude extract having the highest content with 219.0±12.7 mg GAE/g extract followed by G. mangostana crude extract with 247.1±18.0 mg GAE/g extract. Quantification of total flavonoids also showed C. papaya crude extract to contain the highest content with 55.12±0.679 mg QE/g extract. All extracts contained negligible alkaloid content, though. HPLC and TLC profiling showed several peaks and bands, when viewed in 210 nm and UV light, respectively. These results demonstrate in vitro the salivary amylase inhibitory activity of both plants and their potential as antidiabetic drug candidates; however, further studies need to be done, like isolation and structure elucidation of active components and toxicity assays. Keywords: Amylase inhibition, phytochemical quantification, Carica papaya, Garcinia mangostana

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Improved Method for Obtaining of Arctigenin from Arctium Lappa L. and its Antiproliferative Effect on Human Hepatocarcinoma HepG2 Cells

Current Bioactive Compounds ◽

10.2174/1573407214666181115124223 ◽

2020 ◽

Vol 16 (3) ◽

pp. 358-362

Author(s):

Renan S. Teixeira ◽

Paulo H.D. Carvalho ◽

Jair A.K. Aguiar ◽

Valquíria P. Medeiros ◽

Ademar A. Da Silva Filho ◽

...

Keyword(s):

Antitumor Activity ◽

Crude Extract ◽

Hepg2 Cells ◽

Liver Carcinoma ◽

Adhesion Assay ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Arctium Lappa ◽

Nih 3T3

Background: Arctigenin is a lignan found in Arctium lappa L. (Asteraceae) that displays anti-inflammatory activities. Previous studies showed that the crude extract of A. Lappa has antitumor activity in human liver carcinoma, lung and stomach cancer cells. The aim of this study was to obtain arctigenin from A. lappa L., as well as to evaluate its antiproliferative effects in cells of liver carcinoma (HepG2) and fibroblasts (NIH/3T3). Methods: Arctigenin was obtained from the hydrolysis of arctiin, which was isolated from the crude extract of A. lappa. The effects of arctigenin and arctiin on HepG2 cell viability and cell adhesion were analyzed by MTT method. Adhesion assay was also carried out to evaluate the antitumor activity. Results: Our results showed that the analytical process to obtain arctigenin was fast and easy. In vitro experiments showed that arctigenin (107-269 μM) decreased HepG2 cells viability and did not cause cytotoxicity on NIH/3T3 cells. Arctigenin (27-269 μM) demonstrated anti-adhesion in HepG2 cells in a concentration-dependent manner, when compared with control. Conclusion: These results suggest a promising pharmacological activity for arctigenin as an antiproliferative compound.

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Validation of the in vitro comet assay for DNA cross-links and altered bases detection

Archives of Toxicology ◽

10.1007/s00204-021-03102-3 ◽

2021 ◽

Author(s):

Damián Muruzabal ◽

Julen Sanz-Serrano ◽

Sylvie Sauvaigo ◽

Bertrand Treillard ◽

Ann-Karin Olsen ◽

...

Keyword(s):

Comet Assay ◽

Human Health Risk ◽

High Sensitivity ◽

Dna Lesions ◽

Dna Glycosylase ◽

Vitro Assay ◽

Cytotoxic Compound ◽

Endonuclease Iii ◽

Cross Links

AbstractMechanistic toxicology is gaining weight for human health risk assessment. Different mechanistic assays are available, such as the comet assay, which detects DNA damage at the level of individual cells. However, the conventional alkaline version only detects strand breaks and alkali-labile sites. We have validated two modifications of the in vitro assay to generate mechanistic information: (1) use of DNA-repair enzymes (i.e., formamidopyrimidine DNA glycosylase, endonuclease III, human 8-oxoguanine DNA glycosylase I and human alkyladenine DNA glycosylase) for detection of oxidized and alkylated bases as well as (2) a modification for detecting cross-links. Seven genotoxicants with different mechanisms of action (potassium bromate, methyl methanesulfonate, ethyl methanesulfonate, hydrogen peroxide, cisplatin, mitomycin C, and benzo[a]pyrene diol epoxide), as well as a non-genotoxic compound (dimethyl sulfoxide) and a cytotoxic compound (Triton X-100) were tested on TK-6 cells. We were able to detect with high sensitivity and clearly differentiate oxidizing, alkylating and cross-linking agents. These modifications of the comet assay significantly increase its sensitivity and its specificity towards DNA lesions, providing mechanistic information regarding the type of damage.

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Bioactive Compounds Obtained from Polish “Marynka” Hop Variety Using Efficient Two-Step Supercritical Fluid Extraction and Comparison of Their Antibacterial, Cytotoxic, and Anti-Proliferative Activities In Vitro

Molecules ◽

10.3390/molecules26082366 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2366

Author(s):

Katarzyna Klimek ◽

Katarzyna Tyśkiewicz ◽

Malgorzata Miazga-Karska ◽

Agnieszka Dębczak ◽

Edward Rój ◽

...

Keyword(s):

Supercritical Fluid Extraction ◽

Supercritical Fluid ◽

Bioactive Compounds ◽

Crude Extract ◽

Normal Skin ◽

Extraction Methods ◽

Biological Properties ◽

Added Value ◽

Fluid Extraction

Given the health-beneficial properties of compounds from hop, there is still a growing trend towards developing successful extraction methods with the highest yield and also receiving the products with high added value. The aim of this study was to develop efficient extraction method for isolation of bioactive compounds from the Polish “Marynka” hop variety. The modified two-step supercritical fluid extraction allowed to obtain two hop samples, namely crude extract (E1), composed of α-acids, β-acids, and terpene derivatives, as well as pure xanthohumol with higher yield than that of other available methods. The post-extraction residues (R1) were re-extracted in order to obtain extract E2 enriched in xanthohumol. Then, both samples were subjected to investigation of their antibacterial (anti-acne, anti-caries), cytotoxic, and anti-proliferative activities in vitro. It was demonstrated that extract (E1) possessed more beneficial biological properties than xanthohumol. It exhibited not only better antibacterial activity against Gram-positive bacteria strains (MIC, MBC) but also possessed a higher synergistic effect with commercial antibiotics when compared to xanthohumol. Moreover, cell culture experiments revealed that crude extract neither inhibited viability nor divisions of normal skin fibroblasts as strongly as xanthohumol. In turn, calculated selectivity indexes showed that the crude extract had from slightly to significantly better selective anti-proliferative activity towards cancer cells in comparison with xanthohumol.

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Bacterial endosymbiont inhabiting Leucaena leucocephala leaves and their antioxidant and antidiabetic potential

Journal of Complementary and Integrative Medicine ◽

10.1515/jcim-2020-0203 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Sridevi Chigurupati ◽

Shantini Vijayabalan ◽

Kesavanarayanan Krishnan Selvarajan ◽

Ahmad Alhowail ◽

Fatema Kauser

Keyword(s):

Free Radical ◽

Crude Extract ◽

Leucaena Leucocephala ◽

Endophytic Bacteria ◽

Radical Scavenging ◽

16S Rrna Gene Sequencing ◽

Free Radical Scavenging ◽

Rrna Gene ◽

Standard Drug

AbstractObjectivesResearch on endosymbionts is emerging globally and is considered as a potential source of bioactive phytochemicals. The present study examines the antioxidant and antidiabetic of the endophytic crude extract isolated from Leucaena leucocephala leaves.MethodsEndophytic bacteria were isolated from the leaves of L. leucocephala and 16S rRNA gene sequencing was used to establish their identity. The in vitro antioxidant effect of endophytic crude extract (LL) was evaluated using 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) free radical scavenging methods. The in vitro antidiabetic properties of LL were evaluated using α-amylase and α-glucosidase enzyme inhibition assay.ResultsThe isolated endophytic bacteria were identified as Cronobacter sakazakii. LL displayed potent free radical scavenging effect against ABTS and DPPH radicals with an inhibitory concentration 50% (IC50) value of 17.49 ± 0.06 and 11.3 ± 0.1 μg/mL respectively. LL exhibited α-amylase and α-glucosidase inhibition with an IC50 value of 23.3 ± 0.08 and 23.4 ± 0.1 μg/mL respectively compared to the standard drug (acarbose). Both glucose loaded normoglycemic rats and STZ induced diabetic rats treated with LL (200 mg/kg) exhibited a considerable reduction in blood glucose levels p<0.01 after 8 h of treatment when compared to normal and diabetic control rats respectively.ConclusionsThus, the study shows that LL has a wellspring of natural source of antioxidants, and antidiabetic agents and phytoconstituents present in endophytes could be the rich source for bioactive compounds.

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Effects of melatonin on N-nitroso-N-methylurea-induced carcinogenesis in rats and mutagenesis in vitro (Ames test and COMET assay)

Cancer Letters ◽

10.1016/s0304-3835(98)00365-6 ◽

1999 ◽

Vol 138 (1-2) ◽

pp. 37-44 ◽

Cited By ~ 24

Author(s):

Sergei A Musatov ◽

Vladimir N Anisimov ◽

Véronique André ◽

Carole Vigreux ◽

Thierry Godard ◽

...

Keyword(s):

Comet Assay ◽

Ames Test

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An In Vitro Coumarin-Antibiotic Combination Treatment of Pseudomonas aeruginosa Biofilms

Natural Product Communications ◽

10.1177/1934578x20987744 ◽

2021 ◽

Vol 16 (1) ◽

pp. 1934578X2098774

Author(s):

Jinpeng Zou ◽

Yang Liu ◽

Ruiwei Guo ◽

Yu Tang ◽

Zhengrong Shi ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Combination Treatment ◽

Crude Extract ◽

Biofilm Formation ◽

Bacterial Resistance ◽

Antibacterial Properties ◽

Biofilm Growth ◽

Antibiotic Combination

The drug resistance of Pseudomonas aeruginosa is a worldwide problem due to its great threat to human health. A crude extract of Angelica dahurica has been proved to have antibacterial properties, which suggested that it may be able to inhibit the biofilm formation of P. aeruginosa; initial exploration had shown that the crude extract could inhibit the growth of P. aeruginosa effectively. After the adaptive dose of coumarin was confirmed to be a potential treatment for the bacteria’s drug resistance, “coumarin-antibiotic combination treatments” (3 coumarins—simple coumarin, imperatorin, and isoimperatorin—combined with 2 antibiotics—ampicillin and ceftazidime) were examined to determine their capability to inhibit P. aeruginosa. The final results showed that (1) coumarin with either ampicillin or ceftazidime significantly inhibited the biofilm formation of P. aeruginosa; (2) coumarin could directly destroy mature biofilms; and (3) the combination treatment can synergistically enhance the inhibition of biofilm formation, which could significantly reduce the usage of antibiotics and bacterial resistance. To sum up, a coumarin-antibiotic combination treatment may be a potential way to inhibit the biofilm growth of P. aeruginosa and provides a reference for antibiotic resistance treatment.

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Modulation of Oxidative Stress and Hemostasis by Flavonoids from Lentil Aerial Parts

Molecules ◽

10.3390/molecules26020497 ◽

2021 ◽

Vol 26 (2) ◽

pp. 497

Author(s):

Jerzy Żuchowski ◽

Agata Rolnik ◽

Weronika Adach ◽

Anna Stochmal ◽

Beata Olas

Keyword(s):

Oxidative Stress ◽

Antioxidant Activity ◽

Human Plasma ◽

Crude Extract ◽

Lens Culinaris ◽

Bioactive Substances ◽

Phenolic Fraction ◽

Aerial Parts ◽

Scientific Attention

While specific metabolites of lentil (Lens culinaris L.) seeds and their biological activity have been well described, other organs of this plant have attracted little scientific attention. In recent years, green parts of lentils have been shown to contain diverse acylated flavonoids. This work presents the results of the research on the effect of the crude extract, the phenolic fraction, and seven flavonoids obtained from aerial parts of lentils on oxidative damage induced by H2O2/Fe to lipid and protein constituents of human plasma. Another goal was to determine their effect on hemostasis parameters of human plasma in vitro. Most of the purified lentil flavonoids had antioxidant and anticoagulant properties. The crude extract and the phenolic fraction of lentil aerial parts showed antioxidant activity, only at the highest tested concentration (50 μg/mL). Our results indicate that aerial parts of lentils may be recommended as a source of bioactive substances.

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