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

Understanding the phenomena of extraction of essential oils by the microwave accelerated distillation process: case of the Washington Navel variety

In this study, two techniques Hydrodistillation (HD) and Microwave-accelerated distillation (MAD), was used to extract essential oils (EOs), from the peels of citrus fruits Washington Navel (Citrus sinensis L. Osbeck) collected from Tipaza province, north Algeria during April 2018. The extraction yield and time of EOs were (0.28% and 180 min) using HD extraction and (0.27% versus 30 min) using MAD extraction. After using gas chromatography analyses (GC-FID) and (GC-MS), 21 aromatic compounds obtained and identified for both extraction approaches. On the other hand, and in order to better comprehension the extraction phenomena, two models of extraction processes were applied, The first one considers the existence of a single site with a constant speed ruled by the equation of the quasi-stationary state, whereas, the second assumes that there are two distinct sites: The first is part of the fraction easily accessible with a very high desorption rate k1 (fast fraction), the second contains the fraction that is difficult to extract, with a low desorption speed k2 (slow fraction). The results showed that, the application of the two sites model can describe accurately the used extraction methods in this study. The data from HD extraction modeling indicate that this method extraction is fast fraction (f equal 0.79), then MAD method (f equal 0.40). DOI: http://dx.doi.org/10.5281/zenodo.388185

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

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Cold Pressing, Hydrodistillation and Microwave Dry Distillation of Citrus Essential Oil from Algeria: A Comparative Study

International audienceHydro-Distillation (HD), Cold Pressing (CP) and Microwave Clevenger or microwave Accelerated Distillation (MAD) methods have been compared and evaluated for their efficiency in the extraction of essential oil (EO) from fresh Citrus peels. EO from peel of 4 varieties of Algerian sweet orange (C. sinensis), Lemons (C. limon), Citrons (C. medica), sour orange (C. aurantium), grapefruits (C. paradisi) and tangelos (C. deliciosa Ten C. tangerina Hort. ex Tan.) × (C. paradisi Macf.) were analysed by Gas Chromatography-Mass Spectrometry (GC-MS). The EO chemical constituents were identified according to their mass spectra and Kováts retention indices determined on polar and non-polar stationary phase capillary columns. Citrus peel oils contained from 86.69 to 99.31% of monoterpenes with limonene reported to be the major component. The Principal Components Analysis (PCA) and the Canonical Discriminant Analysis (CDA) have been undertaken in order to make a comparison between the three processes of extraction (MAD, HD and CP). The MAD offers significant advantages over traditional alternatives, namely; shorter distillation times (30 min. against 3 h for HD and 1 h for CP); improved yields; environmental impact (energy cost is fairly superior to perform HD and for mechanical motor (CP) than that required for rapid MAD extraction); cleaner features (as no residue generation and no water or solvent used) and provides a more valuable EO (with elevated quantities of oxygenated compounds). Hence, it provides also the ability for enhanced reproduction of natural fragrance of the EO from Citrus fruit

Rapid extraction of volatile compounds from Citrus fruits using a microwave dry distillation

Three different extraction methods were used for a comparative study of essential oil (EO) from fresh Citrus peels: Traditional hydrodistillation (HD), cold pressing (CP) and innovative microwave ‘dry’ distillation or microwave-accelerated distillation (MAD). The microwave process offers significant advantages over conventional alternatives, viz. shorter distillation period (30 min vs. 3 h for hydrodistillation and 1 h for cold pressing); better yields (0.24% vs.0.21% for HD and 0.054% for CP); environmental impact (energy charge is noticeably superior for performing HD and for mechanical motors (CP) than that necessary for quick MAD assay); cleaner features (as no remains creation and no solvent or water used); raises antibacterial properties ; and offers a more precious EO (with high amounts of oxygenatedcompounds)

Cold Pressing, Hydrodistillation and Microwave Dry Distillation of Citrus Essential Oil from Algeria: A Comparative Study

International audienceHydro-Distillation (HD), Cold Pressing (CP) and Microwave Clevenger or microwave Accelerated Distillation (MAD) methods have been compared and evaluated for their efficiency in the extraction of essential oil (EO) from fresh Citrus peels. EO from peel of 4 varieties of Algerian sweet orange (C. sinensis), Lemons (C. limon), Citrons (C. medica), sour orange (C. aurantium), grapefruits (C. paradisi) and tangelos (C. deliciosa Ten C. tangerina Hort. ex Tan.) × (C. paradisi Macf.) were analysed by Gas Chromatography-Mass Spectrometry (GC-MS). The EO chemical constituents were identified according to their mass spectra and Kováts retention indices determined on polar and non-polar stationary phase capillary columns. Citrus peel oils contained from 86.69 to 99.31% of monoterpenes with limonene reported to be the major component. The Principal Components Analysis (PCA) and the Canonical Discriminant Analysis (CDA) have been undertaken in order to make a comparison between the three processes of extraction (MAD, HD and CP). The MAD offers significant advantages over traditional alternatives, namely; shorter distillation times (30 min. against 3 h for HD and 1 h for CP); improved yields; environmental impact (energy cost is fairly superior to perform HD and for mechanical motor (CP) than that required for rapid MAD extraction); cleaner features (as no residue generation and no water or solvent used) and provides a more valuable EO (with elevated quantities of oxygenated compounds). Hence, it provides also the ability for enhanced reproduction of natural fragrance of the EO from Citrus fruit

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

Comparative Study of Essential Oils Extracted from Algerian Myrtus communis L. Leaves Using Microwaves and Hydrodistillation

Two different extraction methods were used for a comparative study of Algerian Myrtle leaf essential oils: solvent-free-microwave-extraction (SFME) and conventional hydrodistillation (HD). Essential oils analyzed by GC and GC-MS presented 51 components constituting 97.71 and 97.39% of the total oils, respectively. Solvent-Free-Microwave-Extract Essential oils SFME-EO were richer in oxygenated compounds. Their major compounds were 1,8-cineole, followed by α-pinene as against α-pinene, followed by 1,8-cineole for HD. Their antimicrobial activity was investigated on 12 microorganisms. The antioxidant activities were studied with the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging method. Generally, both essential oils showed high antimicrobial and weak antioxidant activities. Microstructure analyses were also undertaken on the solid residue of myrtle leaves by Scanning Electronic Microscopy (SEM); it showed that the SFME-cellular structure undergoes significant modifications compared to the conventional HD residual solid. Comparison between hydrodistillation and SFME presented numerous distinctions. Several advantages with SFME were observed: faster kinetics and higher efficiency with similar yields: 0.32% dry basis, in 30 min as against 180 min for HD