Antioxidant and Anti-Inflammatory Effects of Extracts from Pulsed Electric Field-Treated Artichoke By-Products in Lipopolysaccharide-Stimulated Human THP-1 Macrophages

In this study, pulsed electric field (PEF-3 kV/cm; 5 kJ/kg) pretreatment was used to intensify the extractability of valuable intracellular compounds from artichoke by-products during a subsequent aqueous extraction (solid-liquid ratio = 1:10 g/mL, T = 20 °C; t = 120 min). Total phenolic content (TPC), antioxidant activity (DPPH, ABTS) and HPLC-PDA analysis of the artichoke extract (AE) and the biological effects on human cell lines were determined. Chlorogenic acid was found to be the most abundant phenolic compound (53% of the TPC) in the AE. The extract showed good antioxidant properties in a concentration-dependent manner. The potential biological effects of AE were investigated using THP-1 macrophages stimulated by lipopolysaccharides (LPS) as an in vitro model system of oxidative stress. Reduced reactive oxygen species production upon treatment with AE was found. Moreover, AE was able to reduce the secretion of the pro-inflammatory mediators Interleukin-6 and Monocyte Chemoattractant Protein-1 in LPS-stimulated macrophages, as determined by qRT-PCR and ELISA assays. These results highlighted the anti-inflammatory and antioxidant properties of the extracts from PEF-treated artichoke by-products, corroborating their potential application as a source of functional ingredients obtained through a feasible and sustainable process.

Influence of Cynara cardunculus L. Phenolic Compounds on Pseudomonas putida Isolated from the Dairy Industry: Growth and Melanin Bioproduction

Cynara cardunculus L. inflorescence infusion has been used for several centuries as curd in traditional cheese making, such as some highly prized Portuguese cheeses. To promote the sustainable use of all C. cardunculus plants, C. cardunculus extract leaves decoction (CL), inflorescence decoction (CI), chlorogenic acid (CA) (a compound in the plant leaves), and rosmarinic acid (RA) (a similar phenolic compound) solutions were tested for antimicrobial activity against bacteria that may appear on the cheese rind. The antimicrobial activity was evaluated by 15 bacterial strains using two different methodologies: solid and liquid. The influence of these extracts and the phenolic compounds on melanin bioproduction by Pseudomonas putida ESACB 191 was also studied. CA and RA (1 mg/mL) showed antimicrobial activity. CL and CA reduced P. putida ESACB 191 growth in the liquid assay and melanin bioproduction by 6.20 Log CFU/mL and 50%, respectively. Cynarin, CA, and its derivates were identified as the main phenolic compounds (52%) of CL, which may justify its inhibitory action on bacterial growth and melanin bioproduction. Thus, future perspectives include the application of CL extracts with antimicrobial activity in edible films and/or coatings to applied in cheese rind to increase the shelf time.

Artichoke extracts in cancer therapy: do the extraction conditions affect the anticancer activity?

Background

Artichoke is an edible plant that is grown in the Mediterranean region and is known for its antimicrobial, antifungal, antibacterial, antioxidant and anticancer activities. Different artichoke extraction methods can impressively affect the nature as well as the yield of the extracted components.

Main body

The different methods of artichoke extraction and the influence of the extraction conditions on the extraction efficiency are summarized herein. In addition, cancer causalities and hallmarks together with the molecular mechanisms of artichoke active molecules in cancer treatment are also discussed. Moreover, a short background is given on the common types of cancer that can be treated with artichoke extracts as well as their pathogenesis. A brief discussion of the previous works devoted to the application of artichoke extracts in the treatment of these cancers is also given.

Conclusion

This review article covers the extraction methods, composition, utilization and applications of artichoke extracts in the treatment of different cancers.

Valorization of Globe Artichoke (Cynara scolymus) Agro-Industrial Discards, Obtaining an Extract with a Selective Effect on Viability of Cancer Cell Lines

Globe artichoke (Cynara scolymus L.) is considered one of the most significant sources of phenolic antioxidants in nature. However, more than 60% of its total volume is discarded for consumption purposes, making available an abundant, inexpensive and profitable source of natural antioxidants in the discarded fractions. Polyphenolic antioxidants from a South American variety of artichoke agro-industrial discards (external bracts and stems) were obtained by mild extraction processes. Best results were achieved at 40 °C, 75% of ethanol and 10 min of reaction, obtaining 2.16 g gallic acid equivalent (GAE)/100 g of total phenolic compounds (TPC) and 55,472.34 µmol Trolox equivalent (TE)/100 g of antioxidant capacity (oxygen radical absorbance capacity (ORAC)). High-performance liquid chromatography (HPLC) analyses determined that caffeoylquinic acids comprise up to 85% of the total polyphenolic content, and only around 5% are flavonoids. Inulin content in the artichokes residues was recovered (48.4% dry weight (dw)), resulting in an extract with 28% of inulin in addition to the aforementioned antioxidant capacity. The artichoke discard extract in a concentration of 500 mg/L produced a strong decrease in Caco-2 and MCF-7 cancer cell lines viability, whereas healthy fibroblasts maintained their viability when the extract was concentrated at 1500 mg/L. These results suggest that the artichoke extract presents a good anti-proliferative potential effect on Caco-2 and MCF-7 cells.

HPLC-UV and LC-MS Analyses of Acylquinic Acids in Geigeria alata (DC) Oliv. & Hiern. and their Contribution to Antioxidant and Antimicrobial Capacity

INTRODUCTION

Geigeria alata is a traditional plant used in Sudanese folk medicine for treatment of diabetes, cough, epilepsy and intestinal complaints.

OBJECTIVE

To analyze phenolic acids in Geigeria alata roots and leaves and to evaluate their antioxidant and antimicrobial activities.

METHODOLOGY

Phenolic acids in the aqueous-methanol extracts were identified by LC-MS. Major compounds were isolated using low-pressure liquid chromatography. The quantitative analysis of phenolic acids was performed by a validated HPLC-UV method with limits of detection ranging from 0.04 to 0.57 μg/mL. 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazine-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods were used for antioxidant activity evaluation. In addition, the minimal inhibitory concentration and the minimal bactericidal concentration against a panel of pathogenic bacteria and fungi were determined by the broth microdilution test.

RESULTS

For the first time protocatechuic, caffeic, p-coumaroylquinic, caffeoylsinapoylquinic, caffeoylferuloylquinic, three feruloylquinic, six caffeoylquinic acids, and a caffeic acid hexoside were detected in Geigeria alata roots by LC-MS. HPLC-UV analyses showed that 3,5-dicaffeoylquinic acid (25.96 ± 2.08 mg/g dry weight (DW)) was the most abundant phenolic acid in roots, while 4,5-dicaffeoylquinic acid (8.99 ± 0.56 mg/g DW) was the main compound present in leaves. 3,5-Dicaffeoylquinic acid demonstrated stronger radical scavenging activity and reducing power compared with the crude extracts and the positive control 5-caffeoylquinic acid. 3,4,5-Tricaffeoylquinic acid revealed the highest antibacterial potential against the penicillin sensitive and resistant Staphylococcus aureus strains, as well as methicillin-resistant S. aureus.

CONCLUSION

The caffeoylquinic acids content of up to 6.22% in Geigeria alata roots establishes this species as a new source rich in these bioactive molecules. Copyright © 2016 John Wiley & Sons, Ltd.

Simultaneous determination and pharmacokinetic study of eight components in rat plasma by UHPLC-MS/MS after oral administration of Hypericum japonicum Thunb extract

A rapid and sensitive assay based on ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was established and validated for the simultaneous determination of gallic acid, protocatechuic acid, vanillic acid, caffeic acid, epicatechin, isoquercitrin, vincetoxicoside B and quercetin in rat plasma using catechin and daidzein as the internal standards (IS). Plasma samples added internal standards were acidified with formic acid then pretreated by direct protein precipitation with acetonitrile. The separation of eight constituents was achieved on a C18 column with gradient elution using methanol and 0.2% acetic acid aqueous solution as the mobile phase and detected by multiple reaction monitoring using electrospray ionization source in the positive-negative ionization mode. The method was validated for sufficient specificity, precision, accuracy, and sensitivity over the concentration range of 10-6000 ng mL(-1) for gallic acid, 1.5-3000 ng mL(-1) for protocatechuic acid, 10-15000 ng mL(-1) for vanillic acid, 2-3600 ng mL(-1) for caffeic acid, 1.5-3600 ng mL(-1) for epicatechin, 4-6000 ng mL(-1) for isoquercitrin, 2-9000 ng mL(-1) for vincetoxicoside B, and 20-18000 ng mL(-1) for quercetin. The overall intra‑run precision and the inter‑run precision were showed in the range of 1.0-14.2% and 2.8-12.9%, respectively, and the accuracy was no more than 12.8%. This analytical method was successfully applied to investigate the pharmacokinetics of eight ingredients in rats after oral administration of Hypericum japonicum Thunb extract.