Comparative study of antioxidant properties of wild growing and cultivated Allium species

Edible Halophytes and Halo-Tolerant Species in Apulia Region (Southeastern Italy): Biogeography, Traditional Food Use and Potential Sustainable Crops

The Mediterranean basin is rich in wild edible species which have been used for food and medicinal purposes by humans throughout the centuries. Many of these species can be found near coastal areas and usually grow under saline conditions, while others can adapt in various harsh conditions including high salinity. Many of these species have a long history of gathering from the wild as a source of food. The aim of this contribution is an overview on the most important halophyte species (Salicornia sp. pl., Arthrocaulon macrostachyum (Moric.) Piirainen & G. Kadereit, Soda inermis Fourr., Cakile maritima Scop., Crithmum maritimum L., Reichardia picroides (L.) Roth., Silene vulgaris (Moench) Garcke subsp. tenoreana (Colla) Soldano & F. Conti, Allium commutatum Guss., Beta vulgaris L. subsp. maritima (L.) Arcang., Capparis spinosa L.) that traditionally have been gathered by rural communities in southern Italy, with special interest on their ecology and distribution, traditional uses, medicinal properties, marketing and early attempts of cultivation. It is worth noting that these species have an attractive new cash crop for marsh marginal lands.

Effects of nitrogen application on phytochemical component levels and anticancer and antioxidant activities of Allium fistulosum

Background

Allium fistulosum L. has good nutritional value and is cultivated worldwide as an efficacious traditional medicinal plant. Its biological activities are attributable to its phytochemicals. Nitrogen is an essential nutrient for plant growth and development; however, the effect of nitrogen levels on the level of active components in this species is not well understood.

Methods

In this study, using urea fertilizer, we investigated the effects of different nitrogen levels (N0, N1, and N2 at 0, 130, and 260 kg/ha, respectively) on the phytochemical constituents , and antioxidant and anticancer properties of A. fistulosum.

Results

The results suggested that nitrogen fertilizers have a significant effect on the level of total phenols and flavonoids. The analysis of the antioxidant capacity revealed that the lowest IC₅₀ values corresponded to plants treated with the highest nitrogen concentration. Anticancer activity was investigated against cancer cell lines (HeLa and HepG2), and the extracts of A. fistulosum treated with a high nitrogen level showed the highest antiproliferative effect. Collectively, our results suggest that nitrogen fertilizer application enhanced the quality of A. fistulosum, particularly its health benefits.

Natural Antioxidants, Health Effects and Bioactive Properties of Wild Allium Species

BACKGROUND

There is an increasing interest from the pharmaceutical and food industry in natural antioxidant and bioactive compounds derived from plants as substitutes for synthetic compounds. The genus Allium is one of the largest genera, with more than 900 species, including important cultivated and wild species, having beneficial health effects.

OBJECTIVE

The present review aims to unravel the chemical composition of wild Allium species and their healthrelated effects, focusing on the main antioxidant compounds. For this purpose, a thorough study of the literature was carried out to compile reports related to health effects and the principal bioactive compounds. Considering the vast number of species, this review is divided into subsections where the most studied species are presented, namely Allium ampeloprasum, A. flavum, A. hookeri, A. jesdianum, A. neapolitanum, A. roseum, A. stipitatum, A. tricoccum, and A. ursinum, with an additional composite section for less studied species.

METHODS

The information presented in this review was obtained from worldwide accepted databases such as Scopus, ScienceDirect, PubMed, Google Scholar and Researchgate, using as keywords the respective names of the studied species (both common and Latin names) and the additional terms of"antioxidants" "health effects" and "bioactive properties".

CONCLUSION

The genus Allium includes several wild species, many of which are commonly used in traditional and folklore medicine while others are lesser known or are of regional interest. These species can be used as sources of natural bioactive compounds with remarkable health benefits. Several studies have reported these effects and confirmed the mechanisms of action in several cases, although more research is needed in this field. Moreover, considering that most of the studies refer to the results obtained from species collected in the wild under uncontrolled conditions, further research is needed to elucidate the effects of growing conditions on bioactive compounds and to promote the exploitation of this invaluable genetic material.

Hairy Garlic (Allium subhirsutum) from Sicily (Italy): LC-DAD-MSn Analysis of Secondary Metabolites and In Vitro Biological Properties

Allium subhirsutum, known as hairy garlic, is a bulbous plant widespread in the Mediterranean area and locally used as a food and spice. In the present study, the chemical profile of the ethanolic extracts from bulbs (BE) and aerial parts (APE) were analyzed by HPLC-ESI-MSⁿ, and antioxidant properties were evaluated by DPPH, ABTS and TEAC assays. The traditional use in the diet, and the well documented biological activity of Allium species suggest a potential as a new nutraceutical. For this reason, the potential usefulness of this food can be considered in the treatment and prevention of degenerative Alzheimer disease. For this reason, acetylcholinesterase inhibitory property was investigated. Furthermore, due to the observed presence of sulfur-containing and phenolic constituents, the cytotoxicity on tumor cells line was investigated. Results revealed significant AChE inhibitory activity for BE and APE. Both extracts exhibited also moderate antioxidant properties in the in vitro assays. Finally, limited cytotoxic activity was observed towards Human colon carcinoma and adenocarcinoma cell line, with differences between the individual parts tested. HPLC-ESI-MSⁿ analysis showed that hairy garlic is a good source of sulphur compounds, flavonoids and phenylpropanoids derivatives, thus being a valid alternative to the common garlic (A. sativum). This work opens new opportunities for the application of A. subhirsutum as a health-promoting food.

High-Performance Liquid Chromatography/Electrospray Ionization Tandem Mass Spectrometry (HPLC-ESI-MSn) Analysis and Bioactivity Useful for Prevention of "Diabesity" of Allium commutatum Guss

This study aimed at evaluating and comparing the chemical profile obtained by HPLC-ESI-MSⁿ analysis, the inhibitory activity of enzymes linked to obesity (α-amylase, α-glucosidase, and lipase) and the antioxidant properties (DPPH, ABTS, FRAP, and β-carotene bleaching tests) of ethanol extracts of bulbs (BE) and aerial parts (APE) from Allium commutatum Guss. (known in Italy as "aglio delle isole"). The chemical profile revealed alliin as the main abundant compound with values of 31.5 and 38.8 mg/g extract for BE and APE, respectively. APE is rich also in quercetin (38.5 mg/g extract) and luteolin (31.8 mg/g extract). Bulbs extract exhibited the highest activity as inhibitor of enzymes linked to obesity. Except for DPPH test, APE showed the highest antioxidant potential with IC₅₀ of 7.6 and 56.6 μg/mL in ABTS and β-carotene bleaching test after 60 min of incubation, respectively. In conclusion, the present investigation revealed A. commutatum bulbs and aerial parts as a promising source of inhibitors of enzyme linked to the obesity and of antioxidant compounds.

Ethanol extracts of Allium sp. regulate cyclooxygenase-2 and E-cadherin expression in gastric cancer MKN74 cell line and enhance doxorubicin toxicity

BACKGROUND

Gastric cancer (GC) remains one of the leading causes of cancer-related death. Its aetiology is multifactorial, but the major risk factor is a high in salt diet. During gastric carcinogenesis, cadherin-1 (CDH1) down-expression and cyclooxygenase 2 (COX2) overexpression may be observed. The intensity of these alterations contributes to the GC invasion, its metastases and poor prognosis. As the diet plays a significant role in the aetiology of GC, it is reasonable to include the nutritional chemoprevention agents. One of the plant genus demonstrating chemoprotective properties is Allium genus, which includes garlic. The relationship between CDH1 and COX2 in GC cells treated with Allium species extract has never been evaluated.

METHODS

In this study, the MKN28 and MKN74 GC cell lines were treated with ethanol extracts of Allium angulosum L., Allium lusitanicum Lam., Allium sativum L. (from Malaysia and Poland), Allium tibeticum Rendle and Allium ursinum L. The cytotoxicity of the extracts and their influence on COX2 and CDH1 mRNA and protein expression were evaluated as well as their influence on doxorubicin's (DOX) efficacy - a drug that has been used in GC treatment.

RESULTS

Among the tested species, ethanol extracts of A. sativum L. (Poland and Malaysia), A. tibeticum Rendle and A. ursinum L. influenced the levels of CDH1 and COX2, but only in the MKN74 cell line. Thus, it is possible that tumours with increased COX2 expression will be more susceptible to garlic treatment. Observed phenomenon was independent of Allium extract's toxicity. In comparison to DOX, tested extracts were more toxic. Moreover, A. sativum revealed synergistic effect with the drug.

CONCLUSION

In conclusion, the results indicate the potential application of Allium genus to GC chemoprevention and treatment support through CDH restoration and COX2 downregulation. This issue needs further investigations as it might be used in clinics.

Potent antitumor property of Allium bakhtiaricum extracts

BACKGROUND

Allium species are magnificently nutritious and are commonly used as a part of the diet in Iran. They have health enhancing benefits including anticancer properties due to the presence of numerous bioactive compounds. Herein, we investigated in vitro and in vivo anticancer properties of Allium bakhtiaricum extracts.

METHODS

Anti-growth activity of different fractions was explored in vitro on different cancerous cells using MTT assay, Annexin V/PI and SA-β-gal staining, Western blotting, flowcytometric and immunofluorescence microscopic evaluations. In vivo antitumor activity was investigated in BALB/c mice bearing 4 T1 mammary carcinoma cells.

RESULTS

We demonstrated that chloroformic and ethyl acetate fractions exert cytotoxic activity toward MDA-MB-231 cells, the most sensitive cell line, after 72 h of treatment with IC₅₀ values of 0.005 and 0.006 mg/ml, respectively. Incubation of MDA-MB-231 cells with ¼ and ½ IC_50-72h concentrations of each fraction resulted in a significant G2/M cell cycle arrest. ¼ IC_50-72h concentration of the chloroform fraction led to the disruption of polymerization in mitotic microtubules. Exposure of human breast cancer cells to different concentrations of the extracts at different incubation times did not induce apoptosis, autophagy or senescence. Our in vivo study revealed that administration of the chloroform extract at a dose of 1 mg/kg/day strongly suppressed mammary tumor progression and decreased the number of proliferative cells in the lung tissues indicating its anti-metastatic effect.

CONCLUSION

Our findings imply that the chloroform fraction of Allium bakhtiaricum possesses the suppressive action on breast cancer through mitotic cell cycle arrest suggesting a mechanism associated with disturbing microtubule polymerization.

Inhibition of mRNA processing activity from ginger-, clove- and cinnamon-extract, and by two ginger constituents, 6-gingerol and 6-shogaol

Inhibition of mRNA processing, including splicing in the nucleus, is a potential anti-cancer candidate. To obtain mRNA processing inhibitors, we have screened for active constituents from spices. Ginger, clove, and cinnamon showed an inhibitory effect on mRNA processing in the nucleus. Two components in ginger, 6-gingerol and 6-shogaol, exhibited the inhibition of mRNA processing.

Antioxidant Activity of Spices and Their Impact on Human Health: A Review

Antioxidants are substances that prevent oxidation of other compounds or neutralize free radicals. Spices and herbs are rich sources of antioxidants. They have been used in food and beverages to enhance flavor, aroma and color. Due to their excellent antioxidant activity, spices and herbs have also been used to treat some diseases. In this review article, the chemical composition and antioxidant activity of spices and culinary herbs are presented. The content of flavonoids and total polyphenols in different spices and herbs are summarized. The applications of spices and their impacts on human health are briefly described. The extraction and analytical methods for determination of antioxidant capacity are concisely reviewed.

Relationships Between Bioactive Compound Content and the Antiplatelet and Antioxidant Activities of Six Allium Vegetable Species

Allium sp. vegetables are widely consumed for their characteristic flavour. Additionally, their consumption may provide protection against cardiovascular disease due to their antiplatelet and antioxidant activities. Although antiplatelet and antioxidant activities in Allium sp. are generally recognised, comparative studies of antiplatelet and antioxidant potency among the main Allium vegetable species are lacking. Also, the relationship between organosulfur and phenolic compounds and these biological activities has not been well established. In this study, the in vitro antiplatelet and antioxidant activities of the most widely consumed Allium species are characterised and compared. The species total organosulfur and phenolic content, and the HPLC profiles of 11 phenolic compounds were characterised and used to investigate the relationship between these compounds and antiplatelet and antioxidant activities. Furthermore, antiplatelet activities in chives and shallot have been characterised for the first time. Our results revealed that the strongest antiplatelet agents were garlic and shallot, whereas chives had the highest antioxidant activity. Leek and bunching onion had the weakest both biological activities. Significantly positive correlations were found between the in vitro antiplatelet activity and total organosulfur (R=0.74) and phenolic (TP) content (R=0.73), as well as between the antioxidant activity and TP (R=0.91) and total organosulfur content (R=0.67). Six individual phenolic compounds were associated with the antioxidant activity, with catechin, epigallocatechin and epicatechin gallate having the strongest correlation values (R>0.80). Overall, our results suggest that both organosulfur and phenolic compounds contribute similarly to Allium antiplatelet activity, whereas phenolics, as a whole, are largely responsible for antioxidant activity, with broad variation observed among the contributions of individual phenolic compounds.

Study on the antioxidant and antimicrobial activities of Allium ursinum L. pressurised-liquid extract

Allium ursinum L. is widely used as a spice as well as a traditional medicine. The aim of this work was to evaluate the antioxidant and antimicrobial activities (AMAs) of A. ursinum extract, obtained by pressurised-liquid extraction. Several reliable procedures such as 2,2-diphenyl-1-picrylhydrazyl, 2,2-azinobis-3ethyl benxothiazoline-6-sulphonic acid, ferric-reducing antioxidant power assay and oxygen radical absorbance capacity assays were carried out. Vegetable oil stability was evaluated by using Rancimat test. Moreover, AMA was performed on different microorganisms. On the basis of the results obtained, it is confirmed that the A. ursinum extract could be used as a natural ingredient in food and/or pharmaceutical industries.

Comparative study of antioxidant status in androgenic embryos of Aesculus hippocastanum and Aesculus flava

In vivo (leaves and seed embryos) and in vitro (androgenic embryos) antioxidant scavenging activity of Aesculus hippocastanum and Aesculus flava medical plants was examined. Here we report antioxidant enzyme activities of superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase, reduced glutathione quantity, flavonoids, soluble protein contents, quantities of malondialdehyde, and (•)OH radical presence in the investigated plant samples. Total antioxidant capacity of all the samples of A. hippocastanum and A. flava was determined using FRAP, DPPH, and NO(•) radical scavenger capacity. The leaves of A. flava collected from the botanical garden exhibited stronger antioxidant activity (higher activities of SOD, and higher quantities of GSH, TSH, TPC, and scavenging abilities of DPPH and NO(•), and higher FRAP values and lowest quantities of (•)OH and MDA) than in vitro obtained cultures. However, the leaves of A. flava showed higher antioxidant activity than the leaves of A. hippocastanum, and therefore they have a stronger tolerance of oxidative stress. Androgenic embryos of both species had low amount of antioxidants due to controlled in vitro environmental conditions (T, photoperiod, humidity, nutritive factors, and pathogen-free). Our results confirmed that we found optimal in vitro conditions for producing androgenic embryos of both Aesculus species. Also, we assume that horse chestnut androgenic embryos can be used as an alternative source for large-scale aescin production.

Mechanisms of cardioprotective effect of aged garlic extract against Doxorubicin-induced cardiotoxicity

Aged garlic has been extensively studied and has been shown to have a number of medicinal properties, including immunomodulatory, hepatoprotective, antimutagenic, anticarcinogenic, and antioxidant effects. The objective of this study was to investigate the mechanisms of the cardioprotective effect of aged garlic extract (AGE), a widely used herbal medicine with potent antioxidant activity, against doxorubicin-induced cardiotoxicity. Moreover, the study investigated if the cardioprotective effect of AGE might be at the expense of the antitumor effect of the anticancer drug doxorubicin (DOX). Primary cultured neonatal rat cardiac myocytes were treated with DOX, AGE, and their combination for 24 hours. DOX increased p53 and caspase 3 activity-induced apoptotic cell death, whereas AGE pretreatment suppressed the action of DOX. AGE pretreatment did not interfere with the cytotoxic activity of DOX, but it increased the DOX uptake into tumor cells and increased the long term survivors of tumor-bearing mice from 30% to 70%. In conclusion, DOX impairs viability of cardiac myocytes, at least partially by activating the p53-mediated apoptotic signaling. AGE can effectively and extensively counteract this action of DOX and may potentially protect the heart from severe toxicity of DOX. At the same time, AGE did not interfere with antitumor activity of DOX.

Antioxidant and scavenging capacity of Anacamptis pyrimidalis L.--pyrimidal orchid from Vojvodina

In the present study we investigated the antioxidative properties of flowers and aboveground part of Anacamptis pyrimidalis L. from Vojvodina. Activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, and glutathione peroxidase), quantities of malonyldialdehyde, superoxide and hydroxyl radicals and reduced glutathione and also the contents of chlorophylls a and b, carotenoids and soluble proteins were determined. Lipofuscin 'plant age pigments', total antioxidant capacity and scavenging activity were also determined. Our results indicated that the aboveground part of the plant exhibited higher antioxidant activity due to low MDA and lipofuscin pigment accumulation (2.82 nmol/mg protein; 92.90%), higher scavenging activity (54.16%) and antioxidant capacity (432.00 micromol Fe(2+)/dm(3)).

Anatomical characteristics and antioxidant properties of Euphorbia nicaeensis ssp. glareosa

Anatomical analyses found that leaves of Euphorbia nicaeensis ssp. glareosa are isolateral, amphistomatous, with two layers of palisade cells on the adaxial and one on the abaxial side. Laticifers are present by vascular bundles, in palisade and spongy tissue. Stem laticifers are located in the pericyclic ring, adjacent to the phloem, in cylinder parenchyma and medullar rays. The structure of pleiochasium and dichasium peduncle is similar to the stem structure. Plants from typical steppe habitat show more xeromorphic features. Phytochemical screening of extracts showed presence of catecholes, flavonoids, tannins, saponins, free quinone derivatives and absence of anthocyanins, leucoanthocyanins, alkaloids, steroid compounds and essential oils. Our results showed that the examined taxon was partially susceptible to the action of reactive oxygen species, such as O2·− and ·OH. The higher quantities of ROS thus provoked an antioxidative response from the plant, both in an enzymatic and non-enzymatic manner. Stable anatomical structure, presence and distribution of laticifers and effective antioxidant properties when exposed to ROS, make Euphorbia nicaeensis subsp. glareosa potentially interesting for further pharmaceutical and phytochemical examinations.

Comparative study of antioxidant capacity in organs of different Allium species

Cultivated and wild Allium species were investigated in order to compare the antioxidant capacity of their leaves and bulbs. Leaf and bulb anti-oxidative enzymes and scavenger activities, along with quantities of non-enzymic antioxidants, malonyl-dialdehyde and OH radicals were determined. Results obtained suggest that leaves possess higher anti-oxidant and scavenging activities than bulbs in the majority of cultivated and wild Allium species examined. Cultivation of some wild species such as A. flavum L., A. schoenoprasum L. and A. ursinum L. could be conducted in the future in order to produce Allium species with high antioxidant capacity in leaves and bulbs.