Chemometric Approach to the Composition of Flavonoid Compounds and Phenolic Acids and Antioxidant Potential of Artemisia Species from Different Habitats.

Four Artemisia species from Serbia were selected for the study: A. annua L., A. absinthium L., A. vulgaris L. and A. scoparia Waldst. et Kit. because of the proven excellent action in treating certain medical conditions and diseases. A. absinthium L., A. vulgaris L., A. annua L. and A. scoparia Waldst. et Kit. collected from different habitats across Serbia (48 samples in total) were studied from the statistical aspect considering the phenolic and flavonoid contents, compositions, and antioxidant activities of methanol extracts in correlation with the soil type. The components were identified using HPLC (High Performance Liquid Chromatography), while antioxidant activities were determined by seven assays (TP (Total phenolic content), TF (Total flavonoid content), DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-based, ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radical cation-based, FRAP (Ferric Reducing Antioxidant Power), TRP (Total Reducing Power), and CUPRAC (Cupric Reducing Antioxidant Capacity). The results were processed using five statistical methods (PCA (Principal Component Analysis), ANOVA (Analysis of Variance), MANOVA (Multivariate analysis of variance), DA (Discriminant analysis), and AHC (Agglomerative Hierarchical Clustering)). Principal component analysis enabled very well separation of the analyzed Artemisia species based on the content of total phenolics, total flavonoids, and the values obtained from antioxidant tests, but not on the individual compounds identified and quantified by HPLC. The MANOVA analyses showed that for A. scoparia and A. annua there was a significant effect of soil type on the total phenolics, total flavonoids, and antioxidant tests. In contrast, for A. vulgaris and A. absinthium, that effect was not significant. Additional MANOVA analyses showed a significant effect of soil type on phenolic and flavonoid compounds in the case of A. vulgaris, A. annua, and A. absinthium. The overall correct classification rate of all samples of four investigated Artemisia species by the discriminant analysis was 81.25 % using the training sample and 72.92 % the cross-validation results based on TP, TF, and antioxidant tests, but a much lower based on selected compounds identified and quantified by HPLC. MANOVA analyses based on particular Artemisia species show that soil is a significant factor affecting the measurable variables.

The Targeted Pesticides as Acetylcholinesterase Inhibitors: Comprehensive Cross-Organism Molecular Modelling Studies Performed to Anticipate the Pharmacology of Harmfulness to Humans In Vitro.

Commercially available pesticides were examined as Mus musculus and Homo sapiens acetylcholinesterase (mAChE and hAChE) inhibitors by means of ligand-based (LB) and structure-based (SB) in silico approaches. Initially, the crystal structures of simazine, monocrotophos, dimethoate, and acetamiprid were reproduced using various force fields. Subsequently, LB alignment rules were assessed and applied to determine the inter synaptic conformations of atrazine, propazine, carbofuran, carbaryl, tebufenozide, imidacloprid, diuron, monuron, and linuron. Afterwards, molecular docking and dynamics SB studies were performed on either mAChE or hAChE, to predict the listed pesticides' binding modes. Calculated energies of global minima (Eglob_min) and free energies of binding (∆Gbinding) were correlated with the pesticides' acute toxicities (i.e., the LD50 values) against mice, as well to generate the model that could predict the LD50s against humans. Although for most of the pesticides the low Eglob_min correlates with the high acute toxicity, it is the ∆Gbinding that conditions the LD50 values for all the evaluated pesticides. Derived pLD50 = f(∆Gbinding) mAChE model may predict the pLD50 against hAChE, too. The hAChE inhibition by atrazine, propazine, and simazine (the most toxic pesticides) was elucidated by SB quantum mechanics (QM) DFT mechanistic and concentration-dependent kinetic studies, enriching the knowledge for design of less toxic pesticides.

Phenolic profiles and metal ions analyses of pulp and peel of fruits and seeds of quince (Cydonia oblonga Mill.).

Six hydroxycinnamic acids were identified and determined quantitatively in methanol and acetone extracts from quince peel and pulp, namely 3-O-caffeoylquinic acid (3-CQA), 4-p-coumaroylquinic acid (HC1), 4-O-caffeoylquinic acid (4-CQA), 5-O-caffeoylquinic acid (5-CQA), derivative of p-coumaroylquinic acid (HC2) and 3,5-dicaffeoylquinic acid (3,5-diCQA). The most abundant hydroxycinnamic acid was 5-CQA (neochlorogenic acid) with 259.12-481.4mg/kgf.w. in peel and 97.33-217.36mg/kg in quince pulp. Six flavonols were determined in the extracts from quince, quercetin-3-galactoside (Q-Ga), quercetin-3-rutinoside (Q-Ru), quercetin-3-glucoside (Q-Glu), kaempferol-3-rutinoside (K-Ru), kaempferol-3-glucoside (K-Glu) and derivative of quercetin produced in the reaction between quercetin-glucoside and p-coumaric acid (Q-Glu-p-CouA). Elemental analysis of quince seeds has not been performed previously. Also, using principal component and cluster analyses, we determined a strong negative relationship between total phenols and flavonoids, and Ni and Pb, specifically higher concentrations of these compounds were associated with lower concentrations of these metals.