Fingerprinting Cynara scolymus L. (Artichoke) by Means of a Green Statistically Developed HPLC-PAD Method

Reaction of the Phytochemistry Community to Green Chemistry: Insights Obtained Since 1990

This review article aims to study how phytochemists have reacted to green chemistry insights since 1990, the year when the U.S. Environmental Protection Agency launched the "Pollution Prevention Act". For each year in the period 1990 to 2019, three highly cited phytochemistry papers that provided enough information about the experimental procedures utilized were sampled. The "greenness" of these procedures was assessed, particularly for the use of solvents. The highly hazardous diethyl ether, benzene, and carbon tetrachloride did not appear in the papers sampled after 2010. Advances in terms of sustainability were observed mainly in the extraction stage. Similar progress was not observed in purification procedures, where chloroform, dichloromethane, and hexane regularly have been employed. Since replacing such solvents in purification procedures should be a major goal, potential alternative approaches are discussed. Moreover, some current initiatives toward a more sustainable phytochemical research considering aspects other than only solvents are highlighted. Although some advances have been achieved, it is believed that natural products chemists can play a major role in developing a novel ecological paradigm in chemistry. To contribute to this objective, six principles for performing natural products chemistry consistent with the guidelines of green chemistry are proposed.

A green and sustainable method for monitoring the chemical composition of soybean: an alternative for quality control

INTRODUCTION

Soybean is one of the most important crops in the world, an important source of isoflavones, and used to treat various chronic diseases. High-performance liquid chromatography (HPLC), associated with multivariate experiments and green solvents, is increasingly used to develop comprehensive elution methods for quality control of plants and derivatives.

OBJECTIVE

The work aims to establish a HPLC fingerprinting method for soybean seeds employing Green Chemistry Principles, a sustainable solvent with low toxicity, and a comprehensive experimental design that reduces the number of experiments.

MATERIALS AND METHODS

The fingerprinting method was optimised through Design of Experiments by evaluating seven chromatographic variables: initial percentage of ethanol (X1), final percentage of ethanol (X2), temperature (X3), percentage of acetic acid in water (X4), flow rate (X5), run time (X6), and stationary phase (X7). The dependent variable was the number of peaks (n).

RESULTS

An initial factorial design for screening purposes indicated that the most significant quantitative parameters to separate soybean metabolites were X1 and X3. The conditions were optimised by a Doehlert design, to obtain a HPLC-PAD (photodiode array detector) fingerprinting of the polar extract of soybean seeds with the markers identified by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). The optimum fingerprinting method was determined as 5-55% of ethanol in 30 min, at 35°C, and flow rate of 1 mL/min, by employing a phenyl-hexyl column (150 mm × 4.6 mm).

CONCLUSION

The developed green method enabled markers of soybean to be separated and identified and could be an eco-friendlier alternative for soybean quality control that covered seven Green Analytical Chemistry Principles.

Doehlert design in the optimization of procedures aiming food analysis - A review

In the present paper is presented a review on the application of Doehlert design in the optimization of some of the steps of analytical procedures aimed the analysis of food samples. The theoretical principles and the main characteristics of this type of design are described. In addition, the main advantages and limitations of Doehlert design over other designs (Central Composite Design and Box-Behnken) and its application in the area of food analysis are discussed. Finally, to illustrate its potential, some examples of Doehlert design application in other areas of food chemistry without the purpose of analytical determination will be briefly presented.

In vitro genotoxic and antigenotoxic effects of cynarin

ETHNOPHARMACOLOGICAL RELEVANCE

Cynarin is an artichoke phytochemical that possesses a variety of pharmacological features including free-radical scavenging and antioxidant activity. The origin of artichoke species appears to be Mediterranean region. Two of these species, globe artichoke (Cynara cardunculus var. scolymus L.) and cardoon (Cynara cardunculus var. altilis DC), are widely cultivated and consumed. This vegetable, as the basis of the mediterranean diet, has been used as herbal medicine for its therapeutic effects since ancient times. Therefore, this study was performed to determine genotoxic and antigenotoxic effects of cynarin against MMC (mitomycin C) and H₂O₂ (hydrogen peroxide) induced genomic instability using chromosome aberrations (CAs), sister chromatid exchanges (SCEs), micronucleus (MN), and comet assays in human lymphocytes.

MATERIALS AND METHODS

Lymphocytes obtained from two healthy volunteers (1 male and 1 female) were exposed to different concentrations of cynarin (12-194 μM) alone and the combination of cynarin and MMC (0.60 μM) or cynarin and H₂O₂ (100 μM, only for comet assay).

RESULTS

Cynarin alone did not induce significant genotoxic effect in the CA, SCE (except 194 μM), MN, and comet assays. The combination of some concentrations of cynarin and MMC decreased the frequency of CAs, SCEs and MN induced by MMC. Furthermore, the combination of cynarin and H₂O₂ reduced all comet parameters at all the concentrations compared to H₂O₂ alone. While the highest concentrations of cynarin significantly decreased mitotic index (MI), the combination of cynarin and MMC increased the reduction of MI induced by MMC alone.

CONCLUSION

All the results obtained in this study demonstrated that cynarin exhibited antigenotoxic effects rather than genotoxic effects. It is believed that cynarin can act as a potential chemo-preventive against genotoxic agents.

The antioxidant activity of artichoke (Cynara scolymus): A systematic review and meta-analysis of animal studies

Current evidence has shown antioxidant activity of artichoke as a potent source of antioxidant compounds. However, it seems that the antioxidant activity of artichoke has not yet been reviewed. Therefore, the present study was designed to perform a systematic review of human studies, animal models, and in vitro systems and to conduct a meta-analysis of animal studies on the antioxidant effects of artichoke. We searched four electronic databases till April 2018 using relevant keywords. All English language articles were assessed. For animal studies, standardized mean difference was pooled using a random effects model. The included studies were evaluated for eligibility and risk of bias. Thirty-nine articles (two human, 23 animal, and 14 in vitro studies) were reviewed. The results of in vitro systems supported the antioxidant effect of artichoke, whereas limited clinical trials indicated no change or a slight improvement of antioxidant status. Finding of animal studies indicated that artichoke extract supplementation increased superoxide dismutase, catalase, glutathione, and glutathione peroxidase level in liver, as well as, decreased malondialdehyde level in liver and plasma of animals with induced disease significantly compared with comparison group. This meta-analysis provided convincing evidence for antioxidant activity of artichoke in animals.