− Seven flavonoid compounds, kaempferol (1), quercetin (2), quercetin-3-O-β-D-glucopyranoside (3), kaempferol-3-O-β-D-glucopyranoside (4), kaempferol-3-O-α-L-rhamnoside (5), quercetin-3-O-sophoroside (6) and quercetin-3-O-rutinoside (7), were isolated from the methanolic extract of leaves of Kalanchoe prolifera. Compounds 1-7 were isolated for first time from this plant. These compounds were evaluated their cytotoxic activity against P-388 murine leukimia cells in vitro. Among those compounds kaempferol (1) and quercetin (2) showed strongest cytotoxic activity with IC50 values of 4.45 ± 0.05 and 6.28 ± 0.02 μg/mL, respectively.

/pdf/flavonoid-compounds-from-the-leaves-of-kalanchoe-prolifera-2lx3saun76.pdf

Flavonoid Compounds from the Leaves of Kalanchoe prolifera and Their Cytotoxic Activity against P-388 Murine Leukimia Cells

3′-Hydroxy-4′-methoxy-chroman-7-O-β-D-glucopyranoside 4 was first isolated from a natural source, together with three known compounds, the ferulic acid heptyl ester 1, naringenin 2, and 4,2′,4′-trihydroxy-6′-methoxychalcone-4′-O-β-D-glucopyranoside 3, which were isolated from peach [Prunus persica (L.) Batsch] fruits. These compounds were subjected to different virtual screening strategies in order to examine their activity to combat the COVID-19 outbreak. The study design composed of some major aspects: (a) docking with main protease (Mpro), (b) docking with spike protein, (c) 3D shape similarity study (Rapid Overlay Chemical Similarity-ROCS) to the clinically used drugs in COVID-19 patients, and finally, (d) the rule of five and the estimated pre-ADMT properties of the separated flavonoids. Docking study with Mpro of SARS-CoV-2 (PDB ID:6LU7, and 6Y2F) showed that compound 3, its aglycone part, and compound 4 have a strong binding mode to a protease receptor with key amino acids, especially Gln:166AA, and having a similar docking pose to co-crystalized ligands. Docking with the spike protein of SARS-CoV-2 illustrated that compounds 3 and 4 have a good binding affinity to PDB ID:6VSB through the formation of HBs with Asp:467A and Asn:422A. According to ROCS analysis, compounds 1, 3, and 4 displayed high similarities to drugs that prevent SARS-Co2 entry to the lung cells or block the inflammatory storm causing lung injury. Compounds 3 and 4 are good candidates for drug development especially because they showed predicted activity against SARS-CoV-2 through different mechanisms either by preventing genome replication or by blocking inflammatory storm that trigger lung injury. These compounds were isolated from peach fruit, and the study supports data and continues with the recommendation of peach fruits in controlling and managing COVID-19 cases.

/pdf/an-in-silico-perception-for-newly-isolated-flavonoids-from-4a8j2uf075.pdf

An: In silico perception for newly isolated flavonoids from peach fruit as privileged avenue for a countermeasure outbreak of COVID-19

Musa species are used traditionally for the management of many diseases. The study evaluated and compared anticholinesterase, anti-inflammatory, antioxidant, and antidiabetic activities of Musa acuminata (Simili radjah, ABB) fruits and leaves fractions and characterized the bioactive compounds using HPTLC-HRMS and NMR. Leaf fractions gave the higher biological activities than the fruit. Ethyl acetate fraction of the leaf had the highest total phenolic content (911.9 ± 1.7 mg GAE/g) and highest 2,2-diphenyl-1-picrylhydrazyl (DPPH· ) scavenging activity (IC50, 9.0 ± 0.4 µg/ml). It also gave the most effective inhibition of acetylcholinesterase (IC50, 404.4 ± 8.0 µg/ml) and α-glucosidase (IC50, 4.9 ± 1.6 µg/ml), but a moderate α-amylase inhibition (IC50, 444.3 ± 4.0 µg/ml). The anti-inflammatory activity of n-butanol (IC50, 34.1 ± 2.6 µg/ml) and ethyl acetate fractions (IC50 , 43.1 ± 11.3 µg/ml) of the leaf were higher than the positive control, quercetin (IC50 , 54.8 ± 17.1 µg/ml). Kaempferol-3-O-rutinoside and quercetin-3-O-rutinoside (rutin) were identified as the bioactive compounds with antioxidant and antidiabetic activities from the ethyl acetate fraction of M. acuminata leaf. PRACTICAL APPLICATIONS: All parts of Musa acuminata are known to be useful ethnomedicinally even as food. The leaves are mostly used to serve food and used for wrapping purposes. However, this study concluded that M. acuminata leaf is rich in bioactive flavonoids such as kaempferol-3-O-rutinoside and rutin, with relatively high antioxidative, antidiabetic, and anti-inflammatory activities. Therefore, aside the fact that the leaves can serve as potential drug leads for pharmaceutical industries, it can also be embraced in the food sector to produce supplements and/or nutraceuticals in the management of Alzheimer's, diabetes and other inflammatory diseases.

Isolation of flavonoids from Musa acuminata Colla (Simili radjah, ABB) and the in vitro inhibitory effects of its leaf and fruit fractions on free radicals, acetylcholinesterase, 15-lipoxygenase, and carbohydrate hydrolyzing enzymes.

Oil palm (Elaeis guineensis Jacq.) leaflets (OPLs) are one of the major agricultural by-products generated from the massive cultivation of Malaysian palm oil. This biomass is also reported to be of potential value based on its health-improving effects. By employing proton nuclear magnetic resonance (1H-NMR) spectroscopy combined with multivariate data analysis (MVDA), the metabolite profile of OPLs was characterized and correlated with their antioxidant and wound healing properties. Principal component analysis (PCA) classified four varieties of extracts, prepared using solvents ranging from polar to medium polarity, into three distinct clusters. Cumulatively, six flavonoids, eight organic acids, four carbohydrates, and an amine were identified from the solvent extracts. The more polar extracts, such as, the ethyl acetate-methanol, absolute methanol, and methanol-water, were richer in phytochemicals. Based on partial least square (PLS) analysis, the constituents in these extracts, such as (+)-catechin, (-)-epicatechin, orientin, isoorientin, vitexin, and isovitexin, were strongly correlated with the measured antioxidant activities, comprising ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and nitric oxide (NO) free radical scavenging activities, as well as with cell proliferation and migration activities. This study has provided crucial evidence on the importance of these natural antioxidant compounds on the wound healing properties of OPL.

https://www.mdpi.com/1420-3049/25/23/5636/pdf

Metabolite Characterization and Correlations with Antioxidant and Wound Healing Properties of Oil Palm (Elaeis guineensis Jacq.) Leaflets via 1H-NMR-Based Metabolomics Approach.

Two new labdane diterpenoids and one new β-lactam from the aerial parts of Roylea cinerea

We describe the isolation, identification, and structural elucidation of natural products from the Mongolian me- dicinal plant Polygonatum odoratum (Mill.) Druce. Six flavonoid glycosides, isorhamnetin-3-O-rutinoside (narcissoside, narcissin) (1), kaempferol-3-O-rutinoside (nicotiflorin) (2), quercetin-3-O-rutinoside (rutin) (3), apigenin-6-C-� -D- glucoside (isovitexin) (4), apigenin-6-C-(2�� -O-� -D-xylopyranosyl-� -D-glucopyranoside) (desmodin) (5), and isovitexin-7- O-� -D-glucoside (saponarin) (6), were isolated from the aerial parts of Polygonatum odoratum (Mill.) Druce. The struc- tures of 1-6 have been confirmed by UV, IR, MS, and NMR ( 1 H, 13 C, COSY, HSQC, HMBC, NOESY, and ROESY) data. Graphical Abstract:

/pdf/flavonoid-glycosides-from-the-aerial-parts-of-polygonatum-3h43aw004a.pdf

Regdel Duger

Papers

Flavonoid Glycosides from the Aerial Parts of Polygonatum odoratum(Mill.) Druce Growing in Mongolia