It is considered that COVID-19’s pandemic expansion is responsible for the particular increase in deaths, especially among the population with comorbidities. The health system is often overwhelmed by the large number of cases of patients addressing it, by the regional limitation of funds, and by the gravity of cases at subjects suffering from this pathology. Several associated conditions including diabetes, cardiovascular illnesses, obesity, persistent lung condition, neurodegenerative diseases, etc., increase the mortality risk and hospitalization of subjects suffering from COVID-19. The rapid identification of patients with increased risk of death from the SARS-CoV-2 virus, the stratification in accordance with the risk and the allocation of human, financial, and logistical resources in proportion must be a priority for health systems worldwide.
Chemical composition, antioxidant capacity, and antimicrobial activity of lavender essential oils (LEOs) extracted from three different varieties of Lavandula angustifolia Mill. (1-Moldoveanca 4, 2-Vis magic 10, and 3-Alba 7) have been determined. These plants previously patented in the Republic of Moldova were cultivated in an organic agriculture system in the northeastern part of Romania and then harvested in 3 consecutive years (2017–2019) to obtain the essential oils. From the inflorescences in the complete flowering stage, the LEOs were extracted by hydrodistillation. Then, their composition was analyzed by gas chromatography coupled with mass spectrometry (GC-MS) and by Fourier Transformed Infrared spectroscopy (FT-IR). The major identified constituents are as follows: linalool (1: 32.19–46.83%; 2: 29.93–30.97%; 3: 31.97–33.77%), linalyl acetate (1: 17.70–35.18%; 2: 27.55–37.13%; 3: 28.03–35.32%), and terpinen-4-ol (1: 3.63–7.70%; 2: 3.06–7.16%; 3: 3.10–6.53%). The antioxidant capacity as determined by ABTS and DPPH assays indicates inhibition, with the highest activity obtained for LEO var. Alba 7 from 2019. The in vitro antimicrobial activities of the LEOs and combinations were investigated as well, by using the disk diffusion method and minimum inhibitory concentration (MIC) against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538), Gram-negative Pseudomonas aeruginosa (ATCC 27858), Escherichia coli (ATCC 25922), the yeast Candida albicans (ATCC 10231), and clinical isolates. Our results have shown that LEOs obtained from the three studied varieties of L. angustifolia manifest significant bactericidal effects against tested microorganisms (Staphylococcus aureus and Escherichia coli), and antifungal effects against Candida albicans. The mixture of LEOs (Var. Alba 7) and geranium, respectively, in tea tree EOs, in different ratios, showed a significant enhancement of the antibacterial effect against all the studied strains, except Pseudomonas aeruginosa.
In this research, the variations in the chemical composition of the Lavandula angustifolia Mill. essential oil, the Romanian variety Moldoveanca 4, obtained from the same culture, in the same harvesting and extraction conditions, during the years 2016-2018, representing the years 2-4 of culture. Lavandula angustifolia Mill. flowers were supplied from an ecological-crops from N-E Romania and the essential oils were obtained by hydro distillation of freshly harvested flowers. To determine the chemical composition, the essential oil was semi-quantitatively analysed by using gas chromatography coupled with mass spectrometry (GC-MS). In all the samples, 30 organic compounds were identified, linalool and linalyl acetate being in similar concentrations (23.51-27.39% for linalool and 26.60-40.66% for linalyl acetate). Changes in chemical composition were observed in 2017 and 2018. Also, in 2017 was determined an increase in the quantity of linalyl acetate (from 26.60 to 40.66 %), and a slight decrease in linalool content; in 2018, the concentration in linalyl acetate remained approximately the same as in 2017 (38.03 versus 40.66 %) and there was an increase in linalool compared to the previous years (27.39 %, compared to 23.51 % in 2017 and 26.22 % in 2016). The chemical composition of the essential oils obtained from flowers of Lavandula angustifolia L., Moldoveanca 4 variety, showed substantial changes of the chemical profile describing the compounds during the analysed three years, as was determined by GC-MS analyses.
The products used in cosmetic formulations are continuously diversifying as a result of researches in the field, which combine the healing and prevention of many skin conditions with the use of natural products such as vegetable extracts and essential oils. Testing the stability and compatibility of new or modified cosmetics is required to ensure that quality standards are met when stored in proper conditions for functionality and aesthetics, to preserve their chemical, microbiological and physical properties. In this study, the stability and compatibility of a new cosmetic product containing lavender essential oil in plastic container-plastic jar 100 mL PPH Polypropylene homopolymer (Moplen HP648T) is tested against the glass receptacle used as a control. The monitored parameters were organoleptic characteristics (appearance, color, fragrance), physicochemical (pH, density), under controlled temperature conditions, and the microbiological ones. The results of this study showed that the tested cosmetic product is compatible with the plastic container; data obtained were comparable with the organoleptic and physicochemical test results obtained in the case of the control sample stored at room conditions.
Silver nanoparticles (AgNPs) ranging in size from 1-100 nm show good application potential in many medical fields (therapies, medical devices, molecular diagnostics) due to their antimicrobial properties. The purpose of this study is to characterize from physicochemical perspective the colloidal dispersion obtained through phytosynthesis. The existence of colloidal silver particles was visually highlighted through Thyndall effect. The bioreduction of silver ions was analyzed through modern techniques, UV-VIS spectrophotometry and Hyperspectral Microscopy. After getting the colloidal dispersion, its antibacterial activity was proved by sowing on different plates the following types of pathogenic agents: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa. The UV-VIS spectrum for the methanolic extract with 10% H. perforatum L. and for the silver colloidal dispersions was achieved, observing a max at 455 nm. The hyperspectral images were achieved observing the shape, conformation, and the size of the obtained particles. During the antibacterial efficacy testing on those three strains of pathological agents, in all situations, the colloidal dispersion had a promising antimicrobial effect.The term nanotechnology was used for the first time by Norio Taniguchi in 1974, and represents the set of technologies and researches, physical, chemical and biological at the scale of particles with size smaller than 100 nm [1][2][3]. Recently, the nanoparticles from noble metals have been the target of many researches concerning their unique electronic, optical, mechanical, magnetic and chemical properties. Their specific properties are different due to their dimension and the size of their specific surface [4][5][6]. They have applications in different fields: catalysing some reactions, in the electronic field, in photonics, in photography, in textile industry [7,8], in cosmetics industry [9], in dye industry, technical-medical products [10,11], in the diagnosis field [12], in the treatment of different acute and chronical severe diseases like malaria, hepatitis, cancer [13][14][15][16] and AIDS, and as vectors for some medicines [17,18].The antibacterial effect of silver ions has been known for a long time: in concentrations of 1:20.000.000 affect the thiol groups, precipitating the proteins and interfering the vital enzymatic processes of bacterial cells. But the use of AgNPs as antibacterial agent is relatively new. In comparison with the silver ions, the antimicrobial activity of the colloidal silver particles is influenced by the size of the particles, their size being inversely proportional with the antimicrobial effect, due to their increased reactivity determined by the big ratio surface to volume [19].A few preparation methods for the metallic nanoparticles were reported: reduction of some salts, radiolysis, electrochemical synthesis, laser ablation and thermal ablation. In order to get the AgNPs, the simplest method is the reduction of some silver salts -they produced nanoparticles with different morphologi...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.