Phenolics of selected species of Persicaria and Polygonum (Polygonaceae) in Egypt

Four selected species of family Polygonaceae Juss. viz. Persicaria salicifolia (Brouss. ex Willd.) Assenov, Persicaria senegalensis (Meisn.) Soják, Polygonum bellardii All. and Polygonum equisetiforme Sm. were subjected to botanical, chemical and numerical studies. The botanical part deals with macro- and micromorphological characters of the whole plant. The chemical part deals with extraction and identification of 17 compounds including flavones, flavonols, flavone C-glycosides and phenolic acids. The botanical and chemical results of the four selected species were subjected to a numerical analysis

Investigating the trade-off between response time and complexity in the Levenberg–Marquardt ANN-MPPT algorithm used in wind energy conversion systems

Abstract The integration of artificial intelligence (AI) models in renewable energy resources management, particularly in the utilization of maximum power point tracking (MPPT) optimizers, has gained significant attention. This study focuses on investigating the tradeoff between accuracy, response time, and system complexity by varying the number of neurons in artificial neural network (ANN) models for MPPT in wind energy conversion systems (WECSs). Traditionally, MPPT algorithms in WECSs are implemented using direct or indirect methods. However, these methods lack an accumulative learning curve and rely on instantaneous inputs. In contrast, ANN models trained on pre-existing datasets offer the potential for improved maximum point capturing processes. Nevertheless, the incorporation of ANN models may introduce additional complexity to the system. Two ANN models, direct and indirect, are examined in comparison to a reference model using the perturb and observe conventional MPPT algorithm. The results show that the ANN direct model exhibits better time response in the face of high variations in wind speed profiles. On the other hand, the ANN indirect model demonstrates a 4% increase in accuracy with minimal ripples

Maximizing the output power for electric vehicles charging station powered by a wind energy conversion system using tip speed ratio

Abstract This study investigates the influence of tip speed ratio (TSR) as maximum power point tracking (MPPT) technique on energy conversion for wind-powered electric vehicles (EVs) charging stations. The data for 14 different models of (EVs) as well as the energy demand profile for El Sherouk city in new Cairo, Egypt, is used in the study. Those vehicles represent the models that are most likely to be used according to the nature of the Egyptian market from economic and technological concerns. This includes range, battery capacity, battery technology and charging methods. charging can be in the form of fast DC, three phases which are suitable for commercial charging stations or a single phase charging suitable for residential use. A simulation is done using MATLAB/Simulink for a wind turbine Permanent Magnet Synchronous Generator (PMSG) system including TSR MPPT algorithm. The energy output is compared with and without implementing the MPPT algorithms to measure the difference in energy. The system simulation optimized by the TSR MPPT algorithm shows an increase in the energy yield by 41.68%. The economic analysis showed a 30% reduction in the levelized cost of energy while utilizing the TSR concerning a bare system without an MPPT algorithm

Discriminative Metabolomics Analysis and Cytotoxic Evaluation of Flowers, Leaves, and Roots Extracts of <i>Matthiola longipetala</i> subsp. <i>livida</i>

Matthiola longipetala subsp. livida is an annual herb in Brassicaceae that has received little attention despite the family’s high reputation for health benefits, particularly cancer prevention. In this study, UPLC-HRMS-MS analysis was used for mapping the chemical constituents of different plant parts (i.e., flowers, leaves, and roots). Also, spectral similarity networks via the Global Natural Products Social Molecular Networking (GNPS) were employed to visualize their chemical differences and similarities. Additionally, the cytotoxic activity on HCT-116, HeLa, and HepG2 cell lines was evaluated. Throughout the current analysis, 154 compounds were annotated, with the prevalence of phenolic acids, glucosinolates, flavonol glucosides, lipids, peptides, and others. Predictably, secondary metabolites (phenolic acids, flavonoids, and glucosinolates) were predominant in flowers and leaves, while the roots were characterized by primary metabolites (peptides and fatty acids). Four diacetyl derivatives tentatively assigned as O-acetyl O-malonyl glucoside of quercetin (103), kaempferol (108 and 112), and isorhamnetin (114) were detected for the first time in nature. The flowers and leaves extracts showed significant inhibition of HeLa cell line propagation with LC50 values of 18.1 ± 0.42 and 29.6 ± 0.35 µg/mL, respectively, whereas the flowers extract inhibited HCT-116 with LC50 24.8 ± 0.45 µg/mL, compared to those of Doxorubicin (26.1 ± 0.27 and 37.6 ± 0.21 µg/mL), respectively. In conclusion, the flowers of M. longipetala are responsible for the abundance of bioactive compounds with cytotoxic properties

Phytochemical constituents and chemosystematic significance of <i>Chrozophora tinctoria</i> (L.) Raf

<p>Twelve compounds were isolated from <i>Chrozophora tinctoria</i> (L.) Raf. They were identified as kaempferol, kaempferol 3-<i>O</i>-β-glucopyranoside, kaempferol 3-<i>O</i>-(6″-α-rhamnopyranosyl)-β-glucopyranoside, quercetin, quercetin 3-<i>O</i>-β-glucopyranoside, quercetin 3-<i>O</i>-(6″-α-rhamnopyranosyl)-β-glucopyranoside, apigenin, apigenin 7-<i>O</i>-β-glucopyranoside, acacetin, gallic acid, methyl gallate and β-sitosterol-3-<i>O</i>-β-glucopyranoside. Their structures were elucidated by chemical and spectral methods. Furthermore, chemosystematics of the isolated compounds is briefly discussed. It was indicated that <i>C. tinctoria</i> is the only species of <i>Chrozophora</i> that has the capability to synthesis kaempferol aglycone and their glycosides, and the finding is supported by its distinct morphological and anatomical aspects.</p

Composition and Enantiomeric Analysis of the Essential Oil of the Fruits and the Leaves of Pistacia vera from Greece

The essential oils of the fruits and the leaves of pistachio (Pistacia vera L.) were analyzed by GC and GC/MS. Fresh unripe pistachio fruits were richer in essential oil (0.5 %, w/w) than the leaves (0.1 %, w/w). Twenty one compounds were identified in the essential oil of the fruits and the major components were (+)-α-pinene (54.6 %) and terpinolene (31.2 %). The enantiomeric ratio of the major constituents of the essential oil of the fruits was determined using chiral GC/MS and it was found that the (+)/(-)-α-pinene ratio was 99.5:0.5, (+)/(-)-limonene 80:20, (+)/(-)-β-pinene 96:4, and (+)/(-)-α-terpineol 0:100. Thirty three compounds were identified in the essential oil of the leaves and the major components were found to be α-pinene (30.0 %), terpinolene (17.6 %) and bornyl acetate (11.3 %)