Peppermint (Mentha piperita L.) essential oil as a potent anti-inflammatory, wound healing and anti-nociceptive drug

The present investigation was designed to study the chemical composition of Algerian peppermint essential oil (PEO) as well as the in vitro and in vivo anti-inflammatory, wound-healing and anti-nociceptive properties. Twenty-three compounds were identified in the PEO with the main chemical component as menthol (53.29%). Also, PEO showed a high content of oxygenated monoterpene compounds (92.75%). Topical application of PEO at doses of 200 and 20 µL/kg significantly reduced the acute ear edema in 38.09% and 36.50, respectively. Histological observation confirmed that PEO inhibited the skin inflammatory response. In-vivo wound healing activity of the cream prepared from PEO (0.5% w/w) was assessed by circular excision wound model followed by histological examination. The topical administration of PEO cream showed a significant decrease of unhealed wound area rate between the 6th (1.67±0.14 mm2) and the 9th (0.49±0.22 mm2) days of treatment when compared with the vehicle (2.32±0.77 mm2; p<0.05) and Madecassol® 0.1% creams (2.23±0.35 mm2; p<0.05). The PEO reduced nociceptive behavior at all doses tested in the acetic acid-induced nociception test (p<0.05). These findings support the anti-inflammatory, wound-healing and analgesic properties of PEO. We suggest that PEO is a promising candidate for use in skin care products with anti-inflammatory and wound-healing properties. DOI: http://dx.doi.org/10.5281/zenodo.383104

Spearmint (Mentha spicata L.) essential oil from tipaza (Algeria): in vivo anti-infl ammatory and analgesic activities in experimental animal models

Introduction: Although analgesic and nonsteroidal anti-infl ammatory drugs (NSAIDs) are usually used to treat a diversity of illnesses, their administration is linked with acute kidney injury and gastrointestinal side eff ects. The research of new biomolecules and natural products is still needed such as medicinal plants. Aims: The present research was aimed to investigate, for the fi rst time, the anti-infl ammatory and anti-nociceptive eff ects of spearmint essential oil (SEO) in mouse models of acute infl ammation and pain. Materials and Method: Chemical analysis of SEO was done by gas chromatography. The anti-infl ammatory activity was tested using two models of acute infl ammation namely carrageenan-induced paw edema and xylene-induced ear edema. Histological examination of both non-infl amed and infl amed tissues was evaluated. The anti-nociceptive activity was tested using the pain model induced by acetic acid. Results: The main constituent of the SEO was found to be carvone (52.60%). The SEO exhibited a promising anti-infl ammatory eff ect as demonstrated by statistically signifi cant (p<0.05) inhibition of paw volume by 77.24% at the dose of 20 μL/kg and 65.87% at the dose of 200 μL/kg. Furthermore, topical administration of the SEO inhibited xylene-induced ear edema in comparison with the control group (p<0.05). The higher dose (200 μL /kg) signifi cantly (p<0.001) reduced xylene-induced ear edema which was similar to that observed with positive control (ketoprofen). The pathological analysis of the paws and ears revealed that SEO was capable of reducing cellular infi ltration and subcutaneous edema. Else, the SEO produced signifi cant anti-nociceptive activity (p<0.001) at higher dose by inhibiting spontaneous nociception. Conclusion: These results support the use of SEO in the development of pharmaceuticals for the management of infl ammation and pain

Peppermint (Mentha piperita L.) essential oil as a potent anti-inflammatory, wound healing and anti-nociceptive drug

The present investigation was designed to study the chemical composition of Algerian peppermint essential oil (PEO) as well as the in vitro and in vivo anti-inflammatory, wound-healing and anti-nociceptive properties. Twenty-three compounds were identified in the PEO with the main chemical component as menthol (53.29%). Also, PEO showed a high content of oxygenated monoterpene compounds (92.75%). Topical application of PEO at doses of 200 and 20 µL/kg significantly reduced the acute ear edema in 38.09% and 36.50, respectively. Histological observation confirmed that PEO inhibited the skin inflammatory response. In-vivo wound healing activity of the cream prepared from PEO (0.5% w/w) was assessed by circular excision wound model followed by histological examination. The topical administration of PEO cream showed a significant decrease of unhealed wound area rate between the 6th (1.67±0.14 mm2) and the 9th (0.49±0.22 mm2) days of treatment when compared with the vehicle (2.32±0.77 mm2; p<0.05) and Madecassol® 0.1% creams (2.23±0.35 mm2; p<0.05). The PEO reduced nociceptive behavior at all doses tested in the acetic acid-induced nociception test (p<0.05). These findings support the anti-inflammatory, wound-healing and analgesic properties of PEO. We suggest that PEO is a promising candidate for use in skin care products with anti-inflammatory and wound-healing properties. DOI: http://dx.doi.org/10.5281/zenodo.383104

Bactericidal and bioinspired chitin-based anisotropic layer-by-layer brushed-nanocoating

International audienceTop-down biomimetic surfaces with micro/nanotopographic features have emerged as a strategy to prevent bacterial attachment and biofilm formation. These nanostructured surfaces mimic the nano-micro topographical features found naturally on cicada wings. However, their development requires expensive equipment and complex processes. Here, inspired by butterfly wings and crustacean exoskeletons, we present the simple design of fully bio-based, anisotropic, and antibacterial layer-by-layer (LbL) coatings based on chitin nanocrystals (ChNCs). Composed exclusively of US Food and Drug Administration-approved materials, the LbL nanocoatings were obtained by manual brushing of ChNC and Tannic Acid (TA), a natural polyphenol, coordinated by iron III (Fe3+). In contrast to those obtained by the dipping method, the brushed TA/Fe3+/ChNC coatings exhibit highly oriented ChNC nanostructures that enable contact-killing antibacterial properties against Staphylococcus aureus (a Gram-positive bacterium) and Escherichia coli (a Gram-negative bacterium). This antibacterial property is due to the orientation of the ChNC into spike-like nanotopographies with a high density of positive charge on the surface. Similar to cicada and dragonfly wings, the positively charged spikes of the oriented ChNC films are likely to damage the bacterial cell wall by (i) puncturing it upon contact with the spikes and/or (ii) stretching and tearing it when a shear force detaches the cell from the highly positive surface. The fully bio-based nature of ChNC-based nanocoatings and their brush-based fabrication method make them a suitable and affordable candidate as a sustainable antibacterial film for (bio)materials in biomedical and environmental applications