Phytochemical analysis, in vitro and in silico effects from Alstonia boonei De Wild stem bark on selected digestive enzymes and adipogenesis in 3T3-L1 preadipocytes.

BACKGROUND: Obesity is a global health issue arising from the unhealthy accumulation of fat. Medicinal plants such as Alstonia boonei stem bark has been reported to possess body weight reducing effect in obese rats. Thus, this study sought to investigate the in vitro and in silico effects of fractions from Alstonia boonei stem bark on selected obesity-related digestive enzymes and adipogenesis in 3T3-L1 preadipocytes. METHOD: Two fractions were prepared from A. boonei: crude alkaloid fraction (CAF) and crude saponin fraction (CSF), and their phytochemical compounds were profiled using Liquid chromatography with tandem mass spectrometry (LCMS/MS). The fractions were assayed for inhibitory activity against lipase, α-amylase and α-glucosidase, likewise their antiadipogenic effect in 3T3-L1 adipocytes. The binding properties with the 3 enzymes were also assessed using in silico tools. RESULTS: Eleven alkaloids and six saponin phytochemical compounds were identified in the CAF and CSF using LCMS/MS. The CAF and CSF revealed good inhibitory activity against pancreatic lipase enzyme, but weak and good activity against amylase respectively while only CSF had inhibitory activity against α-glucosidase. Both fractions showed antiadipogenic effect in the clearance of adipocytes and reduction of lipid content in 3T3-L1 adipocytes. The LCMS/MS identified compounds (41) from both fractions demonstrated good binding properties with the 3 enzymes, with at least the top ten compounds having higher binding energies than the reference inhibitors (acarbose and orlistat). The best two docked compounds to the three enzymes were firmly anchored in the substrate binding pockets of the enzymes. In a similar binding pattern as the reference acarbose, Estradiol-17-phenylpropionate (-11.0 kcal/mol) and 3α-O-trans-Feruloyl-2 α -hydroxy-12-ursen-28-oic acid (-10.0 kcal/mol) interacted with Asp197 a catalytic nucleophile of pancreatic amylase. Estradiol-17-phenylpropionate (-10.8 kcal/mol) and 10-Hydroxyyohimbine (-10.4 kcal/mol) interacted with the catalytic triad (Ser152-Asp176-His263) of pancreatic lipase while Estradiol-17-phenylpropionate (-10.1 kcal/mol) and 10-Hydroxyyohimbine (-9.9 kcal/mol) interacted with Asp616 and Asp518 the acid/base and nucleophilic residues of modelled α-glucosidase. CONCLUSION: The antiobesity effect of A. boonei was displayed by both the alkaloid and saponin fractions of the plant via inhibition of pancreatic lipase and adipogenesis.

Retaliation of Alstonia scholaris (L.) R.Br. to caesium and strontium in hydroponics: effect on morpho-physiology and induction of enzymatic defence.

The habitation and environment are affected by the stable isotopes of caesium (Cs) and strontium (Sr), as well as by their radioactive isotopes. The current work gives insight on Alstonia scholaris' capacity to phytoextract stable caesium (Cs) and strontium (Sr), as well as the plant's ability to protect against the toxicity of both elements. Experiments with Cs [0-5 mM (CsCl)] and Sr [0-3 mM (SrCl2. 6H2O)] dosing in controlled light, temperature, and humidity condition in greenhouse for 21 days were undertaken. Cs and Sr accumulation in different plant parts was quantified with atomic absorption spectroscopy (AAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES) respectively. Hyper-accumulation capacity for Cs and Sr was estimated with indices like transfer factor (TF) and translocation factors (TrF). The uptake pattern of caesium in Alstonia scholaris is 5452.8-24,771.4 mg/kg DW (TF = 85.2-57.6) and in the case of Sr is 1307.4-8705.7 mg/kg DW (TF = 85.3-1.46). The findings demonstrated the plant's ability to transfer Cs and Sr to aboveground biomass on the basis of dry weight, with the majority of the metals being deposited in the shoot rather than the root portion of the plant. For Cs and Sr, with increasing concentration, the plants exhibited the enzymatic expression for defence against metal toxicity by free radicals compared to control. Field emission electron microscopy with energy-dispersive spectroscopy (FESEM with EDS) was employed to assess the spatial distribution of Cs and Sr in plant leaf, indicating the accumulation of Cs, Sr, and their homologous components.

Metabolic and Proteomic Perspectives of Augmentation of Nutritional Contents and Plant Defense in Vigna unguiculata.

The current study enlists metabolites of Alstonia scholaris with bioactivities, and the most active compound, 3-(1-methylpyrrolidin-2-yl) pyridine, was selected against Macrophomina phaseolina. Appraisal of the Alstonia metabolites identified the 3-(1-methylpyrrolidin-2-yl) pyridine as a bioactive compound which elevated vitamins and nutritional contents of Vigna unguiculata up to ≥18%, and other physiological parameters up to 28.9%. The bioactive compound (0.1%) upregulated key defense genes, shifted defense metabolism from salicylic acid to jasmonic acid, and induced glucanase enzymes for improved defenses. The structural studies categorized four glucanase-isozymes under beta-glycanases falling in (Trans) glycosidases with TIM beta/alpha-barrel fold. The study determined key-protein factors (Q9SAJ4) for elevated nutritional contents, along with its structural and functional mechanisms, as well as interactions with other loci. The nicotine-docked Q9SAJ4 protein showed a 200% elevated activity and interacted with AT1G79550.2, AT1G12900.1, AT1G13440.1, AT3G04120.1, and AT3G26650.1 loci to ramp up the metabolic processes. Furthermore, the study emphasizes the physiological mechanism involved in the enrichment of the nutritional contents of V. unguiculata. Metabolic studies concluded that increased melibiose and glucose 6-phosphate contents, accompanied by reduced trehalose (-0.9-fold), with sugar drifts to downstream pyruvate biosynthesis and acetyl Co-A metabolism mainly triggered nutritional contents. Hydrogen bonding at residues G.357, G.380, and G.381 docked nicotine with Q9SAJ4 and transformed its bilobed structure for easy exposure toward substrate molecules. The current study augments the nutritional value of edible stuff and supports agriculture-based country economies.

Total synthesis of indole alkaloid alsmaphorazine D.

A concise total synthesis of rac-alsmaphorazine D has been described for the first time. The efficient synthetic strategy features four key transformations: 1) a catalytic intramolecular oxidative cyclization for the δ-lactamindole backbone; 2) an oxidative cyclic aminal formation for the hexahydropyrrolo[2,3-b]pyrrole framework; 3) a transannular radical cyclization for the construction of the diazabicyclo[3.3.1]nonane structure; and 4) a one-pot desilylation/double epimerization reaction that affirms the relative stereochemistry.

The role of pentacyclic triterpenoids in the allelopathic effects of Alstonia scholaris.

Alstonia scholaris is a tropical evergreen tree native to South and Southeast Asia. Alstonia forests frequently lack understory species. However, potential mechanisms-particularly the allelochemicals involved-remain unclear. In the present study, we identified allelochemicals of A. scholaris, and clarified the role of allelopathic substances from A. scholaris in interactions with neighboring plants. We showed that the leaves, litter, and soil from A. scholaris inhibited growth of Bidens pilosa-a weed found growing abundantly near A. scholaris forests. The allelochemicals were identified as pentacyclic triterpenoids, including betulinic acid, oleanolic acid, and ursolic acid by using (1)H and (13)C-NMR spectroscopy. The half-maximal inhibitory concentration (IC50) for radicle growth of B. pilosa and Lactuca sativa ranged from 78.8 µM to 735.2 µM, and ursolic acid inhibited seed germination of B. pilosa. The triterpenoid concentrations in the leaves, litter, and soil were quantified with liquid chromatography-electrospray ionization/tandem mass spectrometry. Ursolic acid was present in forest soil at a concentration of 3,095 µg/g, i.e., exceeding the IC50. In the field, ursolic acid accumulated abundantly in the soil in A. scholaris forests, and suppressed weed growth during summer and winter. Our results indicate that A. scholaris pentacyclic triterpenoids influence the growth of neighboring weeds by inhibiting seed germination, radicle growth, and functioning of photosystem II.

Unique monoterpenoid indole alkaloids from Alstonia scholaris.

[structure: see text] A pair of geometrically isomeric monoterpenoid indole alkaloids with a skeleton rearrangement and two additional carbons, named (19,20) E-alstoscholarine (1) and (19,20) Z-alstoscholarine (2), were obtained from the leaf extract of Alstonia scholaris. Their structures were elucidated on the basis of spectroscopic methods and then confirmed by X-ray crystal diffraction. The biogenesis of these compounds was also proposed.

Sperm motility inhibiting activity of a phytosterol from Alstonia macrophylla Wall ex A. DC. leaf extract: a tribal medicine.

The role of methanolic extract and n-butanol fraction of A. macrophylla leaves was investigated on the forward motility of goat spermatozoa. The methanol extract (600 micro/g/ml) and one n-butanol fraction (Fraction A; 100 microg/ml) showed marked inhibition of sperm forward motility, tested by microscopic and spectrophotometric methods. Approximately, 50-60% of the spermatozoa lost their motility when treated with 600 microg/ml of methanol extract or 100 microg/ml of Fraction A. The Fraction A at 400 microg/ml concentration showed complete inhibition of sperm forward motility at 0 min. The inhibitory activity increased with the increasing concentrations of the fraction. The motility inhibitory activity of the Fraction A was stable to heat treatment at 100 degrees C for 2 min. The compound showed high inhibitory effect in the pH range 6.7-7.6. Fraction A also showed high efficacy for inhibiting human sperm motility, assessed by the microscopic method. The phytochemical analysis of methanolic extract of A. macrophylla leaves revealed the presence of sterols, triterpene, flavonoid, alkaloid, tannin and reducing sugar, while the Fraction A contains beta-sitosterol, a common phytosterol. The results demonstrate that Fraction A (beta-sitosterol) is a potent inhibitor of sperm motility and thus it has the potential to serve as a vaginal contraceptive.

Induction of developmental toxicity in mice treated with Alstonia scholaris (Sapthaparna) In utero.

BACKGROUND: The teratogenic effect of hydroalcoholic extract of Alstonia scholaris (ASE) was studied in the pregnant Swiss albino mice administered with 0, 60, 120, 240, 360, and 480 mg/kg ASE on Day 11 of gestation. METHODS: Females were allowed to complete the term and parturiate. The litters were monitored regularly for mortality, growth retardation, congenital malformations, and appearance of physiological markers up to 7 weeks post-parturition (p.p.). RESULTS: The administration of 60, 120, 180, and 240 mg/kg ASE to the pregnant mice on Day 11 did not induce mortality, congenital malformations, or alter the normal growth patterns. A further increase in the herbal extract dose up to 360 or 480 mg/kg resulted in a dose dependent increase in the mortality, growth retardation, and congenital malformations, characterized mainly by bent tails and syndactyly. The administration of higher doses (360 or 480 mg) of ASE also caused a significant delay in the morphological parameters such as fur development, eye opening, pinna detachment, and vaginal opening. The incisor eruption and testes decent were found to be delayed in litters born to the mothers treated with 240-480 mg/kg ASE. CONCLUSIONS: Our study indicates clearly that ASE treatment caused teratogenic effect only at doses above 240 mg/kg (>20% of LD(50)). Lower doses had no developmental toxicity.