Antimicrobial activity of Mentha piperita and Saturenja hortensis in a murine model of cutaneous protothecosis

Anthocyanins and Carotenoids Characterization in Flowers and Leaves of Cyclamen Genotypes Linked with Bioactivities Using Multivariate Analysis Techniques

The present study was carried out to evaluate and compare in vitro antioxidant (2,2-diphenyl-1-picrylhydrazyl (DPPH), Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP)), antimicrobial, anticancer activities, and the individual carotenoids and anthocyanins content of methanol extracts of the Cyclamen genotypes: Persian cyclamen accessions (Cyclamen persicum Mill.), sowbread (C. mirabile Hildebr.), and ivy-leaved cyclamen (C. hederifolium Mill.) aerial parts. The HPLC-PDA analysis revealed the presence of five individual carotenoids (i.e., neoxanthin, violaxanthin, lutein, β-carotene, and cis-β-carotene) as the main compounds in Cyclamen leaves, and the presence of seven individual anthocycanins (i.e., cyanidin 3,5-di-O-glucoside, peonidin-rutinoside, peonidin 3,5-di-O-glucoside, peonidin 3-O-glucoside, malvidin 3-O-glucoside, malvidin 3,5-di-O-glucoside, and malvidin-rutinoside) in Cyclamen flowers reported, hereby, for the first time. The highest phenolic content was found in the leaves of LC6, C. mirabile (46.32 ± 0.14 mg/g gallic acid equivalents [GAE]), and in the flowers of C. persicum Merengue Magenta (FC15) (58.63 ± 0.17 mg/g GAE), whereas the highest flavonoid content was reported in C. persicum Halios Falbala leaves, namely LC9 (54.90 ± 0.27 mg/g quercetin equivalents [QE]) and in flowers of C. persicum Victora (FC2) (77.87 ± 0.25 mg/g QE). The highest antioxidant activity in DPPH and FRAP assays was reported in C. persicum Dark Violet (LC1) and Victoria (LC2), whereas C. mirabile (LC6) had the highest activity in the TEAC assay. In flowers, high antioxidant activities in DPPH and TEAC were noticed in C. persicum Superserie Red (FC7) and Dark Violet (FC1), respectively, and Halios Falbala (FC9) exhibited the highest activity in the TEAC assay. Additionally, FC9 exhibited the highest antibacterial activity in almost all tested bacteria compared with the leaves extracts. Furthermore, the highest in vitro citotoxicity in MDA-MB-231 cells was noticed in C. hederifolium LC18 (56.71-69.35%) and FC18 (40.07-41.43%), with a lower effect against BJ cells demonstrating selective toxicity. The above findings, highlight the potential use of the Cyclamen flower and leaf extracts as significant anticancer agents along with their antioxidant and antimicrobial properties.

Use of Essential Oils in Veterinary Medicine to Combat Bacterial and Fungal Infections

Essential oils (EOs) are secondary metabolites of plants employed in folk medicine for a long time thanks to their multiple properties. In the last years, their use has been introduced in veterinary medicine, too. The study of the antibacterial properties of EOs is of increasing interest, because therapies with alternative drugs are welcome to combat infections caused by antibiotic-resistant strains. Other issues could be resolved by EOs employment, such as the presence of antibiotic residues in food of animal origin and in environment. Although the in vitro antimicrobial activity of EOs has been frequently demonstrated in studies carried out on bacterial and fungal strains of different origins, there is a lack of information about their effectiveness in treating infections in animals. The scientific literature reports some studies about in vitro EOs' activity against animal clinical bacterial and fungal isolates, but in vivo studies are very scanty. The use of EOs in therapy of companion and farm animals should follow careful studies on the toxicity of these natural products in relation to animal species and route of administration. Moreover, considering the different behavior of EOs in relation to both species and strain pathogen, before starting a therapy, an aromatogram should be executed to choose the oil with the best antimicrobial activity.

The activity of silver nanoparticles against microalgae of the Prototheca genus

AIM

To investigate the in vitro activity of silver NPs (AgNPs) against pathogenic microalgae of the Prototheca genus.

MATERIALS & METHODS

The antialgal potential of AgNPs against Prototheca species of both clinical and environmental origin was assessed from minimum inhibitory (algistatic) and algicidal concentrations. The in vitro cytotoxicity of AgNPs against bovine mammary epithelial cell line was evaluated by means of the standard MTT assay.

RESULTS

AgNPs showed a strong killing activity toward Prototheca algae, as the minimal algicidal concentration (MAC) values matched perfectly the corresponding minimum inhibitory concentration (MIC) values for all species (MAC = MIC, 1-4 mg/l), except P. stagnora (MIC > 8 mg/l). The concentrations inhibitory to pathogenic Prototheca spp. (MIC, 1-4 mg/l) were below the concentrations at which any toxicity in epithelial cells could be observed (CC₂₀ > 6 mg/l).

CONCLUSION

The study emphasizes the potential of AgNPs as a new therapeutic tool for the management of Prototheca infections.

In Vitro Activity of 30 Essential Oils against Bovine Clinical Isolates of Prototheca zopfii and Prototheca blaschkeae

Protothecal mastitis poses an emergent animal health problem in dairy herds, with a high impact on dairy industries, causing heavy economic losses. Current methods of treating protothecal infections are ineffective, and no drug is licensed for use in cattle. The aim of the present study was to check the antialgal activity of 30 chemically defined essential oils (EOs) against Prototheca zopfii and Prototheca blaschkeae isolated from the milk of dairy cows with mastitis. A microdilution test was carried out to estimate the antialgal effectiveness of the selected chemically defined EOs. The microdilution test showed different degrees of inhibition among the examined Prototheca species. The activity of some of the examined EOs seem interesting. In particular, Citrus paradisi yielded the lowest minimal inhibitory concentration values (0.75%) for both algal species. P. zopfii appeared to be more sensitive to EOs in comparison to P. blaschkeae. The present study investigated the in vitro susceptibility of P. zopfii and P. blaschkeae to a wide range of EOs, obtained from different botanical families. Further investigations are necessary to evaluate the efficacy of EO-based formulations intended for the disinfection of both udder and milking products.

3-Bromopyruvate as an Alternative Option for the Treatment of Protothecosis

Protothecosis is an unusual infection of both humans and animals caused by opportunistically pathogenic microalgae of the genus Prototheca. Until now, no standardized treatment protocols exist for the protothecal disease, boosted by a remarkable resistance of Prototheca spp. to a wide array of antimicrobial agents currently available in clinical use. Consequently, there is an urgent need for new effective drugs against Prototheca algae. In this study, the anti-Prototheca activity of 3-bromopyruvate (3BP), either alone or in combination with amphotericin B (AMB) was assessed in vitro, as well as the cytotoxicity of 3BP toward the bovine mammary epithelial cells and murine skin fibroblasts. The mean minimum inhibitory concentrations (MIC) and minimum algaecidal concentrations (MAC) were 0.85 ± 0.21 and 2.25 ± 0.54 mM for Prototheca wickerhamii, 1.25 ± 0.47 and 4.8 ± 1.03 mM for Prototheca blaschkeae, and 1.55 ± 0.69 and 5.6 ± 1.3 mM for Prototheca zopfii gen. 2, respectively. For all Prototheca strains tested, a synergistic interaction between 3BP and AMB was observed, resulting in about 4-fold reduction of their individual MICs, when used together. The elevated content of intracellular glutathione (GSH) was associated with a decreased susceptibility to 3BP. Both epithelial and fibroblast cells retained high viability upon treatment with 3BP at concentrations equivalent to the highest MIC recorded (3 mM) and 10-fold higher (30 mM), with the mean cell viability exceeding 80%, essentially the same as for the untreated cells. The results from these in vitro studies emphasize the high activity of 3BP against the Prototheca algae, its synergistic effect when used in combination with AMB, and the safety of the drug toward the tested mammalian cells. Along with the advantageous physico-chemical and pharmacokinetic properties, 3BP may be considered an effective and safe novel agent against the protothecal disease.

The Effect of Some Natural Essential Oils Against Bovine Mastitis Caused by Prototheca zopfii Isolates In Vitro

The aim of the study was to evaluate the effect of essential oils obtained from Thymus vulgaris L., Origanum vulgare L., Origanum majerana L., Mentha × piperita L. and Allium ursinum L. against Prototheca zopfii strains that cause inflammation of the udder (mastitis) in cows. The study was conducted on ten strains derived from milk samples. The microdilution method was used to determine the sensitivity of P. zopfii strains to the studied essential oils, and the disk diffusion method was used to determine the sensitivity to antifungal chemotherapeutics. The plates were incubated for 48 h at 37 °C under aerobic conditions. All strains of algae were sensitive to the essential oils marjoram, thyme and oregano and resistant to mint and garlic oils. MIC values ranged from 0.25 to 1 μl/ml. Marjoram oil demonstrated the greatest activity, and oregano oil the weakest. Among the antifungal agents tested, 90% of strains showed sensitivity to nystatin. One of the tested strains (71/IV) was resistant to all investigated antifungal agents. The tested essential oils are known to have anti-algae activity and can be used as natural agents for prophylaxis in animals, particularly in mastitis-affected cows.

Short communication: Cold atmospheric plasma inactivation of Prototheca zopfii isolated from bovine milk

Mastitis is a serious bovine diseases that can be caused by Prototheca zopfii, yeast-like algae belonging to the family Chlorellaceae. The substantial economic losses and health damage associated with bovine mastitis emphasize the need to develop effective strategies aimed at control of the infection. Unfortunately, P. zopfii is highly resistant to most common antibacterial and antifungal agents, as well as to heat treatment. We report here the first attempt to use cold atmospheric plasma to inactivate this pathogen. We studied 20 strains of P. zopfii isolated from milk samples taken from cows with clinical or subclinical mastitis. The studies confirmed the high level of resistance of P. zopfii to typical antifungal agents, such as voriconazole, fluconazole, amphotericin B, caspofungin, anidulafungin, and micafungin. In contrast, each of the strains revealed high susceptibility to cold atmospheric plasma, >2-fold higher compared with a reference strain of Candida albicans. The obtained results are promising and open up a new approach in the fight against P. zopfii.

The Hydroalcoholic Extract Obtained from Mentha piperita L. Leaves Attenuates Oxidative Stress and Improves Survival in Lipopolysaccharide-Treated Macrophages

Mentha piperita L. (peppermint) possesses antimicrobial properties, but little is known of its ability to modulate macrophages. Macrophages are essential in bacterial infection control due to their antimicrobial functions and ability to link the innate and adaptive immune responses. We evaluated the effects of the peppermint leaf hydroalcoholic extract (LHAE) on cultured murine peritoneal macrophages stimulated or not with lipopolysaccharide (LPS) in vitro. Vehicle-treated cells were used as controls. The constituents of the extract were also identified. Epicatechin was the major compound detected in the LHAE. LPS-induced macrophage death was reversed by incubation with LHAE (1-30 μg/ml). Higher concentrations of the extract (≥100 μg/ml) decreased macrophage viability (49-57%) in the absence of LPS. LHAE (1-300 μg/ml) attenuated H₂O₂ (34.6-53.4%) but not nitric oxide production by these cells. At similar concentrations, the extract increased the activity of superoxide dismutase (15.3-63.5-fold) and glutathione peroxidase (34.4-73.6-fold) in LPS-treated macrophages. Only LPS-unstimulated macrophages presented enhanced phagocytosis (3.6-6.6-fold increase) when incubated with LHAE (3-30 μg/ml). Overall, the LHAE obtained from peppermint modulates macrophage-mediated inflammatory responses, by stimulating the antioxidant pathway in these cells. These effects may be beneficial when the excessive activation of macrophages contributes to tissue damage during infectious disease.

The use of medicinal herbs in gynecological and pregnancy-related disorders by Jordanian women: a review of folkloric practice vs. evidence-based pharmacology

Context National statistical reports in Jordan indicate a decrease in the total fertility rate along with a parallel increase in contraceptive use. The folkloric use of medicinal herbs in gynecological disorders has been growing in Jordan, despite of deficient reports on the evidence-based safety and efficacy of these practices. Objective The aim of this comprehensive article is to review medicinal plants with claimed ethnonpharmacological usage in various gynecological and pregnancy-related issues in Jordan, and to assess their evidence-based pharmacological studies as well as their phytochemistry. Methods The published literature was surveyed using Google Scholar entering the terms "ethnopharmacology AND Jordan AND infertility AND gynecology OR gestation". We included ethnopharmacological surveys in Jordan with available full-text. Results Twelve articles were reviewed. Plant species which are commonly used for female gynecological issues such as Artemisia monosperma Del. and A. herba-alba Asso. (Asteraceae) have been found to exert an antifertility effect. Ricinus communis L. (Euphorbiaceae) and Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) had antifertility effects in male rats, but Nigella sativa oil L. (Ranunculaceae) and Cinnamon zeylanicum J. Presl (Lauraceae) were found to enhance it. Conclusion Using plants for gynecological disorders is a common practice in Jordan. Many of them, whether utilised for gynecological or non-gynecological conditions equally, were found to have detrimental effects on female or male fertility. Thus, couples planning pregnancy should be discouraged from the consumption of these herbs. Further local studies are warranted to confirm the appreciable beneficial pharmacological effects and safety of these plants.