Chemical Compounds, Antitumor and Antimicrobial Activities of Dry Ethanol Extracts from Koelreuteria paniculata Laxm

Koelreuteria paniculata Seed Oil-A Rich Natural Source of Unsaturated Fatty Acids and Phytocompounds with DNA Protective Potential

The present work is focused on the physicochemical characteristics, chemical composition, and some biological activities of Koelreuteria paniculata seed oil. The glyceride oil, obtained with a Soxhlet apparatus by extraction with hexane, was characterized by a relatively high oil content (over 20%), and it is defined as a non-drying oil (iodine value-44 gI₂/100 g) with good oxidative stability (over 50 h). There were identified 11 fatty acids, 6 sterols, 3 tocopherols, and 6 phospholipids, as the last group was reported for the first time. The major components among them were-monounsaturated eicosenoic and oleic acids, β-sitosterol, β-tocopherol, and phosphatidylcholine. The in vitro tests demonstrated DNA protective activity and a lack of cytotoxicity of the oil, data that has been reported for the first time. The in vitro MTT test of the oil on HT-29 and PC3 cell lines did not indicate antitumor activity. The seed oil studied contains valuable bio-components, which have proven benefits for human health, and that is why it could be used in food, cosmetic, and pharmaceutical products.

10th Anniversary of Plants-Recent Advances and Further Perspectives

Published for the first time in 2012, Plants will celebrate its 10th anniversary [...].

Superior inhibition of virulence and biofilm formation of Pseudomonas aeruginosa PAO1 by phyto-synthesized silver nanoparticles through anti-quorum sensing activity

Quorum sensing (QS)-regulated bacterial biofilm formation is a crucial issue in causing resistance against existing antibiotics. There is a considerable necessity to disrupt the interrelationship between bacterial QS, virulence, and biofilm formation. Disabling QS could be a novel tactic of great clinical importance. Here, we biosynthesized silver nanoparticles (Ka-AgNPs) using the aqueous leaf extract of Koelreuteria paniculata as a reducing and capping agents. The UV-Vis spectroscopy confirmed the synthesis of Ka-AgNPs as a characterization peak observed at 420 nm. TEM image revealed the spherical shape distribution of Ka-AgNPs with average particle size of 30.0 ± 5 nm. The anti-QS activity of Ka-AgNPs was tested against a bio-indicator bacterium Chromobacterium violaceum 12472 and a multi-drug resistant model strain of Pseudomonas aeruginosa (PAO1). The results demonstrated that the Ka-AgNPs superiorly inhibited QS-regulated virulence factors in PAO1 without affecting cell viability compared to chemically synthesized AgNPs (Cs-AgNPs). The Ka-AgNPs effectively suppressed the formation of biofilm of PAO1. RT-PCR results revealed that the Ka-AgNPs inhibited the expression of QS-regulated virulence genes of PAO1. These results suggest that the phyto-synthesized AgNPs could be used as promising anti-infective agents for treating drug-resistant P. aeruginosa.

Antioxidant and DNA-Protective Potentials, Main Phenolic Compounds, and Microscopic Features of Koelreuteria paniculata Aerial Parts

Interest in plant extracts as a natural source of antioxidants has grown significantly in recent years. The tree species Koelreuteria paniculata deserves attention due to its wide distribution, good adaptability, and growth to the degree of invasiveness in a number of European countries. The purpose of the present study was to analyze flavonoids and phenolic acids of the ethanol extracts from aerial parts of K. paniculata and to screen their antioxidant and DNA-protective activity. HPLC profiling revealed the presence of five flavonoids, with rutin (4.23 mg/g DW), hesperidin (2.97 mg/g DW), and quercetin (2.66 mg/g DW) as the major ones in the leaves, and (−)-epicatechin (2.69 mg/g DW) in the flower buds. Among the nine phenolic acids identified, rosmarinic, p-coumaric, salicylic, vanillic, and gallic acids were the best represented. All the extracts tested showed in vitro antioxidant activity that was determined by DPPH, ABTS, FRAP, and CUPRAC assays. The highest activity was recorded in the flower parts (in the range from 1133 to 4308 mmol TE/g DW). The DNA-protective capacity of the flower and stem bark extracts from the in vitro nicking assay performed, as well as the main diagnostic microscopic features of the plant substances, are given for the first time. According to the results obtained, the aerial parts of K. paniculata could be valuable sources of natural antioxidants.