Proximate Composition, Minerals and Antioxidant Activity of Artichoke Leaf Extracts

Globe Artichoke (Cynara scolymus L.) By-Products in Food Applications: Functional and Biological Properties

Globe artichoke (Cynara cardunculus var. scolymus L.) is widely cultivated in the Mediterranean area and Italy is one of the largest producers. A great issue is represented by its high amount of by-product, mainly consisting of external bracts and stems, but also of residual leaves, stalks, roots, and seeds. Artichoke by-products are rich in nutrients (carbohydrates and proteins) and bioactive compounds (polyphenols and terpenes) and represent potential ingredients for foodstuffs, functional foods, and food supplements, due to their functional and biological properties. In fact, artichoke by-products' components exhibit many beneficial effects, such as dyspeptic, prebiotic, antioxidant, anti-inflammatory, antiglycative, antimicrobial, anticarcinogenic, and hypolipidemic properties. Therefore, they can be considered potential food ingredients useful in reducing the risk of developing metabolic and age-related disorders. This work summarizes the economic and environmental impact of the recovery and valorization of artichoke by-products, focusing on rheological, physical, and biological properties of the different components present in each by-product and their different food applications.

Investigation of Bioactive Complexes of Chitosan and Green Coffee Bean or Artichoke Extracts

The formation of water-insoluble complexes between chitosan (ChS) and caffeoylquinic acid (CQ) derivatives present in artichoke (AE) and green coffee bean (GCBE) extracts was investigated by the equilibrium adsorption method. The UPLC/HPLC analysis revealed that the phenolic compounds accounted for 8.1% and 74.6% of AE and GCBE respectively, and CQ derivatives were the predominant compounds. According to the applied Langmuir adsorption model, anionic compounds present in natural extracts were adsorbed onto the active centers of ChS, i.e., primary amino groups. The driving forces of adsorption were electrostatic interactions between cationic groups of ChS and anionic compounds of natural extracts. Chromatographic analysis revealed that not only CQ derivatives, but also other phenolic compounds of natural extracts were attached to ChS. The release of adsorbed compounds into different media as well as the bioactive properties of complexes were also studied. With the immobilization of bioactives onto ChS, increased and prolonged ABTS^•+ radical scavenging activity and decreased antifungal activity against Fusarium graminearum and Botrytis cinerea were observed compared to those of ChS. The findings of the current study highlight that the adsorption approach could be used to successfully prepare water-insoluble complexes of ChS and components of natural extracts with prolonged antioxidant activity.

Therapeutic Effects of Milk Thistle (Silybum marianum L.) and Artichoke (Cynara scolymus L.) on Nonalcoholic Fatty Liver Disease in Type 2 Diabetic Rats

BACKGROUND

At present, nonalcoholic fatty liver disease (NAFLD) does not have an approved pharmacologic therapy. The present study investigated the protective effects and possible mechanisms of milk thistle (Silybum marianum L.) and artichoke (Cynara scolymus L.) in treating NAFLD in type 2 diabetic rats.

METHODS

The NAFLD was established in rats after four weeks of type 2 diabetes induction. The animals were treated with pharmaceutical preparations of milk thistle (Livergol®) and artichoke (Atheromod-B®) extracts for eight weeks. After the end of the intervention, oral glucose tolerance, the serum parameters of oxidative stress, liver functional tests, and lipid profiles were evaluated. Histopathological changes were assessed by hematoxylin and eosin staining.

RESULTS

Treatment with preparations of milk thistle and artichoke nonsignificantly improved glucose tolerance in diabetic rats. Both preparations significantly improved serum superoxide dismutase activity and the level of malondialdehyde. Although treatment with milk thistle reduced serum activity of aspartate aminotransferase and serum levels of triglyceride (TG), total cholesterol, and low-density lipoprotein-cholesterol, artichoke extracts only attenuated the serum level of TG. Milk thistle also effectively protected the liver from histological changes.

CONCLUSIONS

Milk thistle could be a promising pharmacological option for the treatment of NAFLD. Nonetheless, long-term randomized clinical trials are necessary to confirm the observed results.

Valorization of Artichoke Industrial By-Products Using Green Extraction Technologies: Formulation of Hydrogels in Combination with Paulownia Extracts

The integral valorization of artichoke bracts generated during industrial canning of artichoke was assessed. The extraction of bioactive compounds was addressed with pressurized hot water under subcritical conditions. The performance of this stage on the extraction of phenolics with antioxidant properties and the saccharidic fraction using conventional and microwave heating was compared. The microwave assisted process was more efficient than the conventional one regarding extraction yields of total solubles, and glucose and fructose oligomers and phenolics, because lower operational temperatures and shorter times were needed. Degradation of fructose oligomers was observed at temperatures higher than 160 °C, whereas the maximal phenolic content occurred at 220 °C. Both the extracts and the residual solids, obtained at conditions leading to maximum phenolics yields, were evaluated for the production of starch-based hydrogels, supplemented with Paulownia leaves' aqueous extracts.

Ferula asafoetida: chemical composition, thermal behavior, antioxidant and antimicrobial activities of leaf and gum hydroalcoholic extracts

This is the first original study on chemical, thermal, antimicrobial, and antioxidant activity of the leaf and gum hydroethanolic (20:80 v/v) extracts of Ferula asafoetida endemic for Iran. The ratio of solvent to the dried matters was 3:1 (w/w) and after filtering, the solvent was evaporated under vacuum (at 40 °C). Leaf extract contained greater phenolic and flavonoid compounds and thus higher DPPH scavenging and ferric reducing power. Leaf extract constituted high levels of carvacrol (15.40%) and α-bisabolol (9.75%) while in gum extract contained high levels of (Z)-b-ocimene (20.91%) and (E)-1-propenyl-sec-butyl-disulfide (17.62%). Umbelliprenin and ferulic acid were the major phenolic compounds in both extracts. Results of TGA and DSC revealed temperatures below and upper 100 °C and 160 °C as dominant regions of weight loss for gum and leaf extracts, respectively. Minimal inhibitory concentration for Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Saccharomyces cerevisiae growth were 62.5, 62.5, 125, 125 mg/l and 400, 300, 50, 300 mg/l of leaf and gum extracts, respectively. Ferula asafoetida extracts can have particular applications in the food industry due to beneficial biological activity.

Elemental measurements and health risk assessment of sub-Saharan African medicinal plants used for cardiovascular diseases' and related risk factors' treatment

BACKGROUND

Dietary factors have been noted to influence the development of cardiovascular diseases (CVDs) which are the number one global cause of death. In this study, the nutritional importance and human health risk of the minerals composition of 20 medicinal plants' (MPs) parts used for treating CVDs and related risk factors in sub-Saharan Africa (SSA) were assessed.

METHODS

Inductively coupled plasma technology was used for determining the minerals composition of the MPs while human health risk assessment was based on hazard quotients, hazard indexes and non-carcinogenic risk analysis of the studied heavy metals.

RESULTS

The investigation showed varied level of minerals in the studied MPs' parts with K having the highest concentration in most. Although level of some elements inM. lucida, V. amygdalina leaves, T. cacao seed and Z. officinale rhizome revealed their possibility in preventing the occurrence of atherosclerosis, unsafe levels of some trace elements were recorded in M. lucida and V. amygdalina leaves. V. amygdalina leaves and A. cepa bulb also had their Pb contents higher than the WHO/FAO Codex permitted maximum level for leafy and bulb vegetables, respectively. In spite of the desirable Na/K and Zn/Cu ratios in all the tested MPs with their Cd and Pb levels below the WHO recommended maximum levels for dried medicinal plant materials, health risk assessment showed that habitual use of almost all of the studied MPs would present an unacceptable risk of non-carcinogenic effects on health. With the exception of S. aromaticum flower bud and T. tetraptera fruit, principal component and hierarchical cluster analyses of other plants' parts (MPs' parts aside from the leaves) analysed provided a distinction between MPs which have found food applications and those solely used for medicinal purposes.

CONCLUSIONS

The study revealed that type of MP, plants' part, maturity stage, agricultural practice, growing environment and conditions, are among the factors determining the safety of plant materials used for CVDs' and related risk factors' treatment in SSA. To protect the lives of CVDs patients who rely on traditional medicine for treatment, government of SSA countries and relevant authorities need to set a regulatory limit for maximum acceptable concentration of minerals in MPs used in the region. Assessment of the physicochemical properties and pollution level of soil used for cultivation of these MPs is also encouraged.

Chemical Composition, Antioxidant Potential and Enzymes Inhibitory Properties of Globe Artichoke By-Products

In this study, chemical composition and in vitro biological activities of artichoke by-products (leaves, floral stems and bracts) issued from two Tunisian varieties were evaluated. Analysis was performed by means of high-performance liquid chromatography with diode array detection coupled to electrospray ionization mass spectrometric (LC/DAD/ESI-MS). Total phenolic (TPC) and flavonoid (TFC) contents as well as the antioxidant activity conducted by three complementary methods, DPPH, ABTS and FRAP tests, were performed for each sample. Enzyme inhibitory effects against acetylcholinesterase, butyrylcholinesterase and α-amylase were also studied. Results showed that TPC and TFC varied according to variety as well as the plant part. Bracts presented the highest TPC values (10-15 mg GAE/g DW), while leaves were distinguished by the highest TFC values (52-58 mg EQ/g DW). In vitro assays showed that Violet d'Hyères bracts and Blanc d'Oran leaves present the most antioxidant activities (30.040 and 20.428 mgET/gDW, respectively, by the DPPH method). Leaves demonstrated the highest acetylcholinesterase and butyrylcholinesterase inhibitory effects. Moreover, all organs displayed a noticeable inhibition towards α-amylase. LC/DAD/MS analysis revealed that artichoke by-products are a potential source of biopharmaceuticals such as luteolin derivatives from leaves and mono/dicaffeoylquinic acids in the other parts. This research demonstrates that globe artichoke by-products, unexploited in our country, are a promising source of natural health promoting compounds with potential applications in the food and pharmaceutical industries.