In vitro and in vivo antileishmanial effects of Nectaroscordum koelzi extract against Leishmania major

Due to the increasing resistance to common medicinal compounds, the use of medicinal plants has received special attention. Therefore, the current survey was designed to study the antileishmanial effects of Nectaroscordum koelzi Trautv. methanolic extract against Leishmania major. In this study, after preparing the methanolic extract of N. koelzi, its effect on the amastigotes of L. major and triggering the nitric oxide (NO) were measured. Then, the in vivo effect of the methanol extract on cutaneous leishmaniasis in mice was evaluated. The best anti-amastigote effect was for the methanol extract of N. koelzi along with meglumine antimony with 50% inhibitory concentrations value of 17.4 μg/ml (p < 0.001). The 50% cytotoxic concentrations values of methanol extract, meglumine antimoniate, and methanol extract + meglumine antimoniate were 596.3, 784.6, and 296.4 µg/ml, respectively. Macrophages treated with the methanolic extract markedly (p < 0.001) induced the release of nitric oxide. After 28 days of treatment, lesions were completely (p < 0.001) healed in mice treated with the methanolic extract (100 mg/kg) + meglumine antimoniate (25 mg/kg). N. koelzi methanolic extract mainly in combination with meglumine antimoniate showed favorable antileishmanial effects on L. major, concluding that the methanolic extract of N. koelzi can be used for the production of new leishmanicidal agents agaist cutaneous leishmaniasis. Although we revealed that NO trigerring and inhibition of infection in host cells are the antileishmanial mechanism action of N. koelzi methanolic extract, more studies must be performed to clear the mechanisms and its safety.

Plants and Mushrooms as Possible New Sources of H2S Releasing Sulfur Compounds

Hydrogen sulfide (H2S), known for many decades exclusively for its toxicity and the smell of rotten eggs, has been re-discovered for its pleiotropic effects at the cardiovascular and non-cardiovascular level. Therefore, great attention is being paid to the discovery of molecules able to release H2S in a smart manner, i.e., slowly and for a long time, thus ensuring the maintenance of its physiological levels and preventing "H2S-poor" diseases. Despite the development of numerous synthetically derived molecules, the observation that plants containing sulfur compounds share the same pharmacological properties as H2S led to the characterization of naturally derived compounds as H2S donors. In this regard, polysulfuric compounds occurring in plants belonging to the Alliaceae family were the first characterized as H2S donors, followed by isothiocyanates derived from vegetables belonging to the Brassicaceae family, and this led us to consider these plants as nutraceutical tools and their daily consumption has been demonstrated to prevent the onset of several diseases. Interestingly, sulfur compounds are also contained in many fungi. In this review, we speculate about the possibility that they may be novel sources of H2S-donors, furnishing new data on the release of H2S from several selected extracts from fungi.

Two new species of Miersia and their phylogenetic placements alongside the recently described M.putaendensis (Gilliesieae, Allioideae, Amaryllidaceae)

Two new species of the Chilean endemic genus Miersia (Gilliesieae, Allioideae, Amaryllidaceae) are described, M.stellata and M.raucoana, alongside morphological descriptions, a distribution map, illustrations, conservation status assessments, and an updated key to all species of Miersia. Additionally, phylogenetic analyses of DNA sequences were performed to inquire into the evolutionary affinities of both new species and the recently described, M.putaendensis, within the tribe Gilliesieae.

Potential Effects of Natural H2S-Donors in Hypertension Management

After the discovery of hydrogen sulfide (H₂S) in the central nervous system by Abe and Kimura in 1996, the physiopathological role of H₂S has been widely investigated in several systems such as the cardiovascular. In particular, H₂S plays a pivotal role in the control of vascular tone, exhibiting mechanisms of action able to induce vasodilation: for instance, activation of potassium channels (KATP and Kv7) and inhibition of 5-phosphodiesterase (5-PDE). These findings paved the way for the research of natural and synthetic exogenous H₂S-donors (i.e., molecules able to release H₂S) in order to have new tools for the management of hypertension. In this scenario, some natural molecules derived from Alliaceae (i.e., garlic) and Brassicaceae (i.e., rocket or broccoli) botanical families show the profile of slow H₂S-donors able to mimic the endogenous production of this gasotransmitter and therefore can be viewed as interesting potential tools for management of hypertension or pre-hypertension. In this article, the preclinical and clinical impacts of these natural H₂S-donors on hypertension and vascular integrity have been reviewed in order to give a complete panorama of their potential use for the management of hypertension and related vascular diseases.

Allium hooshidaryae (Alliaceae); Chemical compositions, biological and ethnomedicine uses

ETHNOPHARMACOLOGICAL RELEVANCE

Allium hooshidaryae (sect. Pseudoprason) is a wild plant in northwestern Iran. The plant is traditionally used, besides as spice, also for its medicinal properties.

AIM OF THE STUDY

Due to the shortcoming evidence in scientific research and the importance of this plant in folk medicine, this study aims to assess the chemical compositions and biological activities, which have no longer reported to date.

MATERIALS AND METHODS

The bulbs of A. hooshidaryae were collected from West Azerbaijan, Iran. The plant essential oil was obtained by hydrodistillation using Clevenger-type apparatus according to the European pharmacopeia. The plant hydromethanolic extract was obtained using maceration method. The volatile oil compositions of A. hooshidaryae bulbs were evaluated by use of combined gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS) techniques. Furthermore, different biological activities of the yielded essential oil and hydromethanolic extract were in vitro evaluated. The antibacterial and antifungal activities were assessed using disc diffusion assay, tube dilution assay, minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), and minimal fungicidal concentration (MFC). The cytotoxic activities were assayed by reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) toward two human cancerous cell lines (MOLT-4 and MCF-7). Antioxidant activity was investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH^•) radical scavenging assay.

RESULTS

GC/FID and GC/MS analyses allowed detecting 62 components in the A. hooshidaryae essential oil representing the 91.87% of the total oil. The volatile compounds were identified by comparison of the relative retention indices (RRI), mass spectra with those in NIST08/NIH and Wiley (257 and 7 L) libraries and co-elution with authentic samples where available. Surprisingly, the most abundant compound was obtained as menthol (19.0%) followed by carvacrol (10.1%), menthone (6.4%), methyl (methylthiomethyl) disulfide (4.2%), dimethyl disulfide (3.8%), and thymol (3.8%). Contrary to the other Allium species enriched by sulfur compounds, just three compounds accounting for 10.7% of the total oil were obtained as the sulfur-sulfur bond containing components (Dimethyl disulfide, Methyl (methylthio) methyl disulfide, Bis-methylthiomethyl disulfide). The hydromethanolic extract of A. hooshidaryae showed higher anti-radical (IC_50DPPH of 9.81 μg/mL) and cytotoxic (for MOLT-4 and MCF-7, IC_50s were 76.3 and 128.6 μg/mL, respectively) activities rather than that of the obtained essential oil (IC_{50 DPPH} of 39.9 μg/mL; IC_{50 MOLT-4} of 109.2 μg/mL, and IC_{50 MCF-7} of 297.5 μg/mL). While, the essential oil exhibited the anti-Staphylococcus aurous and anti-Escherichia coli activities approximately the same as Chloramphenicol (positive control). The MIC values were 31.25 and 62.5 μg/mL and the disk inhibition zone values were 23 and 21 mm, respectively. In addition, Candida albicans had moderate sensitivity (MFC of 62.5 μg/mL) for the essential oil.

CONCLUSIONS

The hydromethanolic extract of A. hooshidaryae shows the potency to be used for food protection in addition to further cytotoxic investigations. Associated with antimicrobial abilities of both A. hooshidaryae products, the compatible results was observed with the traditional claim having being not investigated to date. These findings will facilitate the development of A. hooshidaryae for further deep investigations.

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.

Pharmacological modulation of the hydrogen sulfide (H2 S) system by dietary H2 S-donors: A novel promising strategy in the prevention and treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) represents the most common age-related metabolic disorder, and its management is becoming both a health and economic issue worldwide. Moreover, chronic hyperglycemia represents one of the main risk factors for cardiovascular complications. In the last years, the emerging evidence about the role of the endogenous gasotransmitter hydrogen sulfide (H₂ S) in the pathogenesis and progression of T2DM led to increasing interest in the pharmacological modulation of endogenous "H₂ S-system". Indeed, H₂ S directly contributes to the homeostatic maintenance of blood glucose levels; moreover, it improves impaired angiogenesis and endothelial dysfunction under hyperglycemic conditions. Moreover, H₂ S promotes significant antioxidant, anti-inflammatory, and antiapoptotic effects, thus preventing hyperglycemia-induced vascular damage, diabetic nephropathy, and cardiomyopathy. Therefore, H₂ S-releasing molecules represent a promising strategy in both clinical management of T2DM and prevention of macro- and micro-vascular complications associated to hyperglycemia. Recently, growing attention has been focused on dietary organosulfur compounds. Among them, garlic polysulfides and isothiocyanates deriving from Brassicaceae have been recognized as H₂ S-donors of great pharmacological and nutraceutical interest. Therefore, a better understanding of the therapeutic potential of naturally occurring H₂ S-donors may pave the way to a more rational use of these nutraceuticals in the modulation of H₂ S homeostasis in T2DM.

Variability in Bulb Organosulfur Compounds, Sugars, Phenolics, and Pyruvate among Greek Garlic Genotypes: Association with Antioxidant Properties

In order to assess the diversity of Greek garlic (Allium sativum L.) landraces, 34 genotypes including commercial ones were grown in the same field and their content in organosulfur compounds, pyruvate, total sugars, and total phenolics, alongside antioxidant capacity, was determined. The organosulfur compounds were studied by Gas Chromatography–Mass Spectrometry (GC–MS) after ultrasound-assisted extraction in ethyl acetate, identifying 2-vinyl-4H-1,3-dithiin and 3-vinyl-4H-1,2-dithiin as the predominant compounds, albeit in different ratios among genotypes. The bioactivity and the polar metabolites were determined in hydromethanolic extracts. A great variability was revealed, and nearly one-third of landraces had higher concentration of compounds determining bioactivity and organoleptic traits than the imported ones. We recorded strong correlations between pyruvate and total organosulfur compounds, and between antioxidant capacity and phenolics. In conclusion, chemical characterization revealed great genotype-dependent variation in the antioxidant properties and the chemical characters, identifying specific landraces with superior traits and nutritional and pharmaceutical value.

Indeterminate growth of the umbel inflorescence and bulb is associated with increased expression of the TFL1 homologue, AcTFL1, in onion

TERMINAL FLOWER1 (TFL1) is a key gene for maintenance of vegetative and inflorescence indeterminacy and architecture. In onion, flowering and bulbing are two distinct developmental phases, each under complex environmental regulatory control. We have identified two CEN/TFL1-like genes from onion designated as AcTFL1 and AcCEN1. AcTFL1 is expressed during bulbing and inflorescence development with expression increasing with indeterminate growth of the umbel and the bulb suggesting possible conservation of function. Increase in AcTFL1 expression during umbel growth is associated with a simultaneous reduction in expression of AcLFY. Expression of AcTFL1 within the bulb is lowest in the outermost layers and highest in the innermost (youngest) layers. Bulb storage at room temperature or in cold leads to a gradual reduction in AcTFL1 levels in the meristem-containing tissues, the decrease being faster in the variety not requiring vernalization. Constitutive expression of AcTFL1, but not AcCEN1 complements the Arabidopsis tfl1-14 mutant and delays flowering in wild type suggesting conservation of the AcTFL1 function even in the distantly related Arabidopsis. Taken together, AcTFL1 appears to be the functional counterpart of TFL1 and regulates indeterminate growth of the umbel inflorescence as well as bulb development in onion.

Using headspace solid-phase microextraction for comparison of volatile sulphur compounds of fresh plants belonging to families Alliaceae and Brassicaceae

In this study, an optimisation of extraction of sulphur volatile compounds (SVCs) has been performed using Central Composite Design. The conditions of the highest amount of eluated peaks and total peaks area have been treated. Factors such as coating of fiber for SPME (Solid Phase Microextraction), extraction temperature and extraction time have been optimised. The SVCs have shown the optimal extraction using a DVB/CAR/PDMS (divinylbenzene/carboxen/polydimethylsiloxane) fiber at 73 °C during 50 min. Furthermore, a pre-incubation step lasting 20 min at the extraction temperature has been used. In total, 12 samples have been investigated at the mentioned optimal conditions, eight from the Alliaceae and four from the Brassicaceae family. The highest number of SVCs (24) has been identified in the sample of chive. The most frequently identified compound found in 11 of 12 samples has been dimethyl trisulphide.

Morphological, nutritional and chemical description of "Vatikiotiko", an onion local landrace from Greece

"Vatikiotiko" is an onion local landrace from Greece with special quality features, such as strong and pungent taste and storability. In this study, we tried for the first time to describe this landrace and record its morphological traits and nutritional value in comparison with commercially cultivated genotypes ("Creamgold", "Red Cross F1" and "Sivan F1"). Nutritional value of "Vatikiotiko" was higher than commercial genotypes, whereas total sugars, fructose and glucose content were lower in "Vatikiotiko" and "Creamgold" onions. Fatty acids composed mostly from polyunsaturated fatty acids (linoleic and α-linolenic acid), whereas for "Vatikiotiko" saturated and monounsaturated fatty acids were detected in equal amounts (29.79% and 30.60%, respectively). "Vatikiotiko" and "Creamgold" had low antioxidant activity (DPPH radical scavenging activity), especially when comparing with "Sivan F1" and "Red Cross F1", whereas no flavonoids were detected in "Vatikiotiko". The overview of "Vatikiotiko" landrace supported its special character regarding its nutritional value (sugar content, mineral composition and fatty acids profile) and the necessity to revalorize and protect its traditional culture. The potential of introducing it as Protected Designation of Origin (PDO) or Protected Geographical Indication (PGI) product has also been discussed.

Evaluation of Anti-Platelet Aggregation Effect of Some Allium Species

Epidemiologic studies show that the cardiovascular diseases are associated with multiple factors such as raised serum total cholesterol, increased LDL, increased platelet aggregation, hypertension and smoking. In-vitro studies have confirmed the ability of some plants of Allium species to reduce these parameters. Therefore, we evaluated anti-platelet aggregation effect of some Allium species (Allium ampeloprasum, A. hirtifolium, A. haemanthoides, A. vavillovi, A. atroviolaceum, A. jesdianum, A. shelkovnikovii) using arachidonic acid (AA) and adenosine diphosphate (ADP) as platelet aggregation inducers. The screening results for methanolic extract of Allium species showed that the maximum effect of anti-platelet aggregation was related to A. atroviolaceum. This extract inhibited the in-vitro platelet aggregation induced by AA and ADP with IC50 values of 0.4881 (0.4826-0.4937) mg/ml and 0.4945 (0.4137-0.5911) mg/ml respectively. These results support the hypothesis that the dietary intake of Allium could be beneficial for prevention of cardiovascular diseases.

Structural characterization and gastroprotective property of a novel glucofructan from Allium ampeloprasum var. porrum

A new polysaccharide with an estimated weight-average molar mass of 2.6×10(3) was isolated from Allium ampeloprasum var. porrum by hot water extraction, and purified by Sephacryl S-300 HR high-resolution chromatography. It was composed of D-fructose and D-glucose in 10:6 molar ratio, respectively. The structure of the glucofructan was investigated by chemical and spectroscopic methods, including methylation analysis, nuclear magnetic resonance, and electrospray mass spectrometry (ES-MS). The results permitted the structure of the glucofructan to be written as α-D-Glcp-(1→1)-β-D-Fruf-(2→1)-{[α-D-Glcp-(1→6)-β-D-Fruf-(2→6)]-β-D-Fruf-(2→1)}4-β-D-Fruf-(2↔1)-α-D-Glcp. Results of the present study indicated that this new glucofructan exhibited significant gastroprotective property, using in vivo experimental models.

The genus Tulbaghia (Alliaceae)--a review of its ethnobotany, pharmacology, phytochemistry and conservation needs

ETHNOPHARMACOLOGICAL RELEVANCE

Tulbaghia is a monocotyledonous genus of herbaceous perennial bulbs predominantly found in Africa. The approximately 63 species have nutritive, ornamental and medicinal value. For centuries, several Tulbaghia species have found diverse uses in traditional medicine.

AIM OF THE REVIEW

To evaluate and document the uses, especially the medicinal value of the genus Tulbaghia. The existing gaps in knowledge and possible means for greater development are highlighted.

METHODS

A comprehensive and detailed literature search using electronic search (for example, Google Scholar, Scirus and Web of Science) and ethnobotanical books was conducted.

RESULTS

Findings based on their traditional uses and scientific evaluation indicates that Tulbaghia violacea remain the most widely used species. Compiled data indicate their efficacy in several in vitro and in vivo pharmacological properties such as antimicrobial, anti-hypertensive, antioxidant and anti-cancer activities. Some phytochemicals which are partly associated with the exhibited bioactivities have been identified and isolated from Tulbaghia violacea and Tulbaghia alliacea. The increasing high usage especially the underground organs, as well as the incessant reliance on the wild population, will eventually affect their abundance and possibly make them susceptible to extinction.

CONCLUSIONS

The great potential of the genus Tulbaghia, particularly other less popular species, remain to be exploited. Further studies on the structural activity relationship of some of the isolated compound may improve their biological potency. Their characteristic alliaceous aroma may also be of great interest to the food industry seeking novel source of unusual aromas to satisfy increasing consumer demands. In order to derive the much anticipated benefits from the species without compromising their conservation status, the use of different biotechnological approaches highlighted in this review will certainly guarantee their continuous availability.