Bioassay-Guided Isolation, Metabolic Profiling, and Docking Studies of Hyaluronidase Inhibitors from Ravenala madagascariensis.

Hyaluronidase enzyme (HAase) has a role in the dissolution or disintegration of hyaluronic acid (HA) and in maintaining the heathy state of skin. Bioassay-guided fractionation of Ravenala madagascariensis (Sonn.) organ extracts (leaf, flower, stem, and root) testing for hyaluronidase inhibition was performed followed by metabolic profiling using LC-HRMS. Additionally, a hyaluronidase docking study was achieved using Molecular Operating Environment (MOE). Results showed that the crude hydroalcoholic (70% EtOH) extract of the leaves as well as its n-butanol (n-BuOH) partition showed higher HAase activity with 64.3% inhibition. Metabolic analysis of R. madagascariensis resulted in the identification of 19 phenolic compounds ranging from different chemical classes (flavone glycosides, flavonol glycosides, and flavanol aglycones). Bioassay-guided purification of the leaf n-BuOH partition led to the isolation of seven compounds that were identified as narcissin, rutin, epiafzelechin, epicatechin, isorhamnetin 7-O-glucoside, kaempferol, and isorhamnetin-7-O-rutinoside. The docking study showed that narcissin, rutin, and quercetin 3-O-glucoside all interact with HAase through hydrogen bonding with the Asp111, Gln271, and/or Glu113 residues. Our results highlight Ravenala madagascariensis and its flavonoids as promising hyaluronidase inhibitors in natural cosmetology preparations for skin care.

Above the Invasive and Ornamental Attributes of the Traveler's Palm: An In Vitro and In Silico Insight into the Anti-Oxidant, Anti-Enzymatic, Cytotoxic and Phytochemical Characterization of Ravenala madagascariensis.

Ravenala madagascariensis is a widely known ornamental and medicinal plant, but with a dearth of scientific investigations regarding its phytochemical and pharmacological properties. Hence, these properties were appraised in this study. The DPPH (154.08 ± 2.43 mgTE/g), FRAP (249.40 ± 3.01 mgTE/g), CUPRAC (384.57 ± 1.99 mgTE/g), metal chelating (29.68 ± 0.74 mgEDTAE/g) and phosphomolybdenum assay (2.38 ± 0.07 mmolTE/g) results demonstrated that the aqueous extract had the most prominent antioxidant activity, while the methanolic extract displayed the best antioxidant potential in the ABTS assay (438.46 ± 1.69 mgTE/g). The HPLC-ESI-Q-TOF-MS-MS analysis allowed the characterization of 41 metabolites. The methanolic extract was the most active against acetylcholinesterase. All extracts were active against the alpha-amylase and alpha-glucosidase enzymes, with the ethyl acetate extract being the most active against the alpha-amylase enzyme, while the methanolic extract showed the best alpha-glucosidase inhibition. A plethora of metabolites bonded more energetically with the assayed enzymes active sites based on the results of the in silico studies. R. madagascariensis extracts used in this study exhibited cytotoxicity against HT29 cells. The IC50 of the methanolic extract was lower (506.99 ug/mL). Based on the heat map, whereby flavonoids were found to be in greater proportion in the extracts, it can be concluded that the flavonoid portion of the extracts contributed to the most activity.

Bio-guided isolation of androsta-1,4-dien-3,16-dione as a vasodilator active principle from the inflorescence of Ravenala madagascariensis Sonn. (Strelitziaceae).

Androsta-1,4-dien-3,16-dione was isolated for the first time from the plant kingdom of the ethanolic extract of the Ravenala madagascariensis' inflorescence by the bio-guided method. Its structure was elucidated by NMR and MS spectroscopic data analysis. The vascular effects of ethanol extracts, fractions and androsta-1,4-dien-3,16-dione were assessed on the phenylephrine pre-contracted isolated rat aorta. The isolated compound exerted the most potent vaso-relaxing effect (EC50 = 109.32 ± 15.82 µM) than the ethanol extract and fractions. The pharmacological mechanism of its vaso-relaxing action was analysed on isolated rat aorta using free-endothelial vascular tissue, specific contracting reagents (CaCl2 and KCl), antagonist (propranolol), enzyme inhibitors (L-NAME, methylene blue) and channel blocker (glibenclamide). Its vaso-relaxing activity could be due, at least partly, to the non-specific inhibition of the calcic influx.

Molecular and Morphological Characterization of an Unusual Meloidogyne arenaria Population from Traveler's Tree, Ravenala madagascariensis.

An unusual variant of Meloidogyne arenaria was discovered on roots of a traveler's tree (Ravenala madagascariensis) intended for display at a public arboretum in Pennsylvania. The population aroused curiosity by the lack of visible galling on the roots of the infected plant, and the female vulval region was typically surrounded by egg sacs. Most morphometrics of the population fit within the ranges reported for M. arenaria, with a mosaic of features in common with either M. platani or other tropical Meloidogyne spp. Molecular characterization included analysis of four loci. The mitochondrial sequence, extending from cytochrome oxidase II (COII) to the 16S (1RNA) gene, was nearly identical to another M. arenaria population and closely related to sequences from M. morocciensis and M. thailandica. The 28S D2-D3 expansion segment was most similar to those from M. arenaria, M. incognita and M. paranaensis, and the IGS-2 was most related to those from M. thailandica, M. arenaria and M. incognita. Analysis of partial Hsp90 genomic sequences revealed the greatest similarity to M. arenaria, M. thailandica and an Hsp90 haplotype from M. floridensis, and a composite sequence comprised of EST from M. arenaria. No morphological or molecular features clearly distinguished this population as a new species, and, when considered as a whole, the evidence points to its identification as M. arenaria.