Study of the Chemical Composition of Rosa beggeriana Schrenk's Fruits and Leaves

Rosa species are widely used in folk medicine in different countries of Asia and Europe, but not all species are studied in-depth. For instance, Rosa beggeriana Schrenk, a plant which grows in Central Asia, Iran, and some parts of China, is little described in articles. Column and thin-layer chromatography methods were used to isolate biologically active substances. From a study of fruits and leaves of Rosa beggeriana Schrenk, a large number of compounds were identified, seven of which were isolated: 3β,23-dihydroxyurs-12-ene (1), β-sitosterol (2), betulin (3), (+)-catechin (4), lupeol (5), ethyl linoleate (6), and ethyl linolenoate (7). Their structures were elucidated by 1H, DEPT and 13C NMR spectroscopy, mass spectrometry, and GC-MS (gas chromatography-mass spectrometry). The study also identified the structures of organic compounds, including volatile esters and acids. Consequently, comprehensive data were acquired concerning the chemical constitution of said botanical specimen.

[Determination of four fatty acid ethyl esters in olive oil by solid phase extraction-gas chromatography]

The fatty acid ethyl ester (FAEE) content of olive oil is an important indicator of its quality. At present, the international standard method used to detect FAEEs in olive oil is silica gel (Si) column chromatography-gas chromatography (GC); however, this technique presents a number of disadvantages, including complex operation, long analysis times, and high reagent consumption. In this study, a method based on Si solid phase extraction (SPE)-GC was established to determine four FAEEs in olive oil, namely, ethyl palmitate, ethyl linoleate, ethyl oleate, and ethyl stearate. First, the effects of the carrier gas were investigated, and He gas was ultimately selected as the carrier gas. Next, several internal standards were screened, and ethyl heptadecenoate (cis-10) was determined as the optimal internal standard. The SPE conditions were also optimized, and the effects of different brands of Si SPE columns on the recoveries of analytes were compared. Finally, a pretreatment method in which 0.05 g of olive oil was extracted with n-hexane and purified through a Si SPE column (1 g/6 mL) was developed. A sample could be processed within approximately 2 h using a total reagent volume of about 23 mL. Validation of the optimized method revealed that the four FAEEs have good linearities within the range of 0.1-5.0 mg/L (coefficients of determination (R²)>0.999). The limits of detection (LODs) of the method were within 0.78-1.11 mg/kg, and its limits of quantification (LOQs) were in the range of 2.35-3.33 mg/kg. The recoveries ranged from 93.8% to 104.0% at all spiked levels tested (4, 8, and 20 mg/kg), and the relative standard deviations were 2.2%-7.6%. Fifteen olive oil samples were tested using the established method, and the total FAEEs of three extra-virgin olive oil samples were found to exceed 35 mg/kg. Compared with the international standard method, the proposed method has the advantages of simpler pretreatment process, shorter operation time, lower reagent consumption and detection cost, high precision, and good accuracy. The findings provide an effective theoretical and practical reference for improving olive oil detection standards.

Efficacy and safety of Politranexamide® liposomal emulsion on facial melasma: A comparative study

INTRODUCTION

Melasma is a human melanogenesis dysfunction that results in localized, chronic acquired hypermelanosis of the skin difficult to treat.

METHODS

This prospective, randomized, single-blind, study aimed to compare the efficacy and tolerability of a liposomal emulsion based on Politranexamide® (SAMPLE A) with that of a competitor based on acetylglucosamine, ethyl linoleate and phenyl ethyl resorcinol (SAMPLE B) in patients affected by facial melasma on 26 patients. Disease severity was assessed by the Melasma Area Severity Index (MASI) at baseline and after 6 and 12 weeks of therapy. All patients were subjected to photo documentation using DermaView camera and Antera 3D camera.

RESULTS

The mean MASI score at baseline was 10.93 ± 7 in the group A and 9.34 ± 6.29 in the group B, respectively. A significant decrease in MASI score from baseline was noted in both treatment groups as early as 6 weeks of follow-up (p = 0.00096 for SAMPLE A and p = 0.0049 for SAMPLE B) and was confirmed at the end of the treatment (p = 0.0006 for SAMPLE A and p = 0.00039 for SAMPLE B). Intergroup comparison revealed a greater improvement of melasma among patients in group A compared to those in group B that was quite statistically significant at weeks 6 (p = 0.055009) and significant after 12 weeks of follow-up (p = 0.032942). Both treatment groups experienced an improvement in Antera average level of melanin.

CONCLUSION

Our results suggested Politranexamide® to be a useful and safe therapeutic option in treating melasma, more effective than competitor used in this study.

Modeling the Evolution of Crosslinked and Extractable Material in an Oil-Based Paint Model System

The construction of mechanistic models for the autoxidation of fatty acid or ester substrates found in oil paint binders is a challenging undertaking due to the complexity of the large crosslinked species that form, and the small molecules that volatilize. Building models that capture this product diversity are made possible by automating the process of network generation. This work presents a microkinetic model for the autoxidation of ethyl linoleate catalyzed by cobalt(II) 2-ethyl hexanoate. The mechanism size was controlled by using a rate-based criterion to include the most kinetically relevant reactions from among the millions of possible reactions generated. The resulting model was solved and compared to experimental metrics. Quantities such as hexanal production and the consumption of unsaturated moieties were in good agreement with experiment. Finally, the model was used to explore the effect of the catalyst concentration and temperature on key measurables.

Evaluation of phytochemicals from medicinal plants of Myrtaceae family on virulence factor production by Pseudomonas aeruginosa

Virulence factors regulated by quorum sensing (QS) play a critical role in the pathogenesis of an opportunistic human pathogen, Pseudomonas aeruginosa in causing infections to the host. Hence, in the present work, the anti-virulence potential of the medicinal plant extracts and their derived phytochemicals from Myrtaceae family was evaluated against P. aeruginosa. In the preliminary screening of the tested medicinal plant extracts, Syzygium jambos and Syzygium antisepticum demonstrated a maximum inhibition in QS-dependent violacein pigment production by Chromobacterium violaceum DMST 21761. These extracts demonstrated an inhibitory activity over a virulence factor, pyoverdin, production by P. aeruginosa ATCC 27853. Gas chromatography-mass spectrometric (GC-MS) analysis revealed the presence of 23 and 12 phytochemicals from the extracts of S. jambos and S. antisepticum respectively. Three top-ranking phytochemicals, including phytol, ethyl linoleate and methyl linolenate, selected on the basis of docking score in molecular docking studies lowered virulence factors such as pyoverdin production, protease and haemolytic activities of P. aeruginosa to a significant level. In addition, the phytochemicals reduced rhamnolipid production by the organism. The work demonstrated an importance of plant-derived compounds as anti-virulence drugs to conquer P. aeruginosa virulence towards the host.

Chinese yam extracts containing β-sitosterol and ethyl linoleate protect against atherosclerosis in apolipoprotein E-deficient mice and inhibit muscular expression of VCAM-1 in vitro

Atherosclerosis is a chronic inflammatory disease, which is associated with increased expression of adhesion molecules and monocyte recruitment into the arterial wall. This study evaluated whether hexane extracts from the edible part (DB-H1) or bark region (DB-H2) of Dioscorea. batatas Decne have anti-atherosclerotic properties in vivo and in vitro experiments. We also identified bioactive components in the hexane extracts. Thirty-six apolipoprotein E (ApoE(-/-) ) mice and 12 control (C57BL/6J) mice were given a Western-type diet for 11 or 21 wk. To examine the effects of yam extracts on lesion development, ApoE(-/-) mice were orally administered DB-H1 or DB-H2 for the duration of the study (200 mg/kg b.w./day, 3 times per wk). Both DB-H1 and DB-H2 significantly reduced the total atherosclerotic lesion area in the aortic root. In addition, plasma concentrations of total cholesterol, oxidized-low-density lipoprotein, and c-reactive protein were decreased by administration of DB-H1 and DB-H2. Consistent with the in vivo observations, DB-H1 and DB-H2 inhibited tumor necrosis factor (TNF)-α-induced vascular cell adhesion molecule-1 expression and adhesion of THP-1 monocytes to TNF-α-activated vascular smooth muscle cells. It was also found that treatment with DB-H1 or DB-H2 resulted in the inhibition nitric oxide (NO) and reactive oxygen species production and iNOS expression in macrophages. Thus, DB-H1 and DB-H2 seem to influence atherosclerosis by affecting the production of inflammatory mediators in vivo. Our results suggest that yam extracts have the potential to be used in the prevention of atherosclerosis.