Don Leaf Research Articles

Pancreatic beta cell regenerative effect of Costus pictus D Don leaf extracts on streptozotocin induced diabetes on Wistar rats

With the increasing prevalence of diabetes and the economic burden caused by its treatment, people seek alternative medicine. Costus pictus D Don, belonging to the family Costaceae, commonly called Insulin plant/spiral ginger, is preferred by many in recent days. The current study was carried out to determine the effect of methanolic leaf extract of Costus pictus D Don on the pancreas of diabetic-induced albino Wistar rats. Methanolic extract from C.pictus was prepared by soxhalation. The effect of this extract at the dose of 100 mg and 200 mg/kg bw was studied biochemically on blood glucose and blood insulin levels. Histological and histo-morphological observations were studied on the pancreas after 21 days of treatment. The parameters were compared with diabetic and normal rats. Glucose-lowering effect of the plant extract was observed biochemically in diabetic animals treated with both doses of the extracts. It was observed that the effect was more pronounced with 200 mg/kg BW of the extract. The presence of hyperchromic islet cells, granulated beta cells, increase in diameter of islets and number of beta cells as observed by histological examination and histo-morphometric analysis revealed the pancreatic beta cell regenerative property of Costus pictus D Don.

Spectrochemical analysis of seasonal and sexual variation of antioxidants in Corema album (L.) D. Don leaf extracts

Bioactive phytoconstituents have been increasingly investigated for their potential human health benefits. Corema album (L.) D. Don, an Ericaceae, reportedly has antioxidant, antimicrobial and anticancer properties. Aiming at enhancing its nutraceutical potential, we performed a spectrochemical analysis of hydroethanolic extracts from C. album leaves. We report on changes in the antioxidant activity of the extracts, as well as in the accumulation of key phytoconstituents (namely phenolic compounds), in female and male samples, throughout three harvesting seasons (February, July, and October). For each extract, the antioxidant activity was assessed by different spectrophotometric methods. Simultaneously, attenuated total reflectance Fourier transform mid-infrared spectroscopy (FTIR-ATR), and high-performance liquid chromatography – electrospray ionisation – quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF-MS), were used to identify and monitor variations in the composition of phenolic compounds in the extracts. The main compounds identified were epicatechin, laricitrin-O-hexoside isomers, and myricetin-O-hexoside isomers. Significant differences were found in the composition and relative abundance of the compounds of interest, according to sex and season. Overall, a trend was observed whereby phenolic content and antioxidant activities were higher in males and increased between the earlier and the latest harvests. Based on these results, we may conclude that late summer or early autumn harvests are preferable when aiming at the highest yearly content of bioactive compounds. Additionally, it should be considered that extracts from male individuals typically display higher antioxidant activities. Ultimately, our understanding of C. album in the context of nutraceutical applications is benefited from the quantitative and qualitative portrait provided here, thus promoting its relevance as a source of bioactive compounds.

Bioefficacy of ursolic acid and its derivatives isolated from Catharanthus roseus (L) G. Don leaf against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi larvae.

The aim of the present study was to identify the active principle from Catharanthus roseus leaf using larvicidal bioassay against three mosquito species viz. Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. Preliminary studies of the three successive extracts such as hexane, chloroform, and methanol against Ae. aegypti larvae showed that the chloroform extract was more active with LC50 and LC90 values of 40.09ppm and 189.15ppm respectively. Bioassay guided fractionation of the active chloroform extract resulted in the isolation of a triterpenoid (ursolic acid) as the active constituent. Three derivatives acetate, formate, and benzoate were prepared using this, and they were tested for their larvicidal activity against three mosquito species. The acetyl derivative was highly active against all the three species compared to the parent compound ursolic acid; the activities of benzoate and formate were higher than ursolic acid when tested against Cx. quinquefasciatus. This is the first report related to ursolic acid from C. roseus with mosquito larvicidal activity. The pure compound could be considered for medicinal and other pharmacological applications in future.

Potential Anti-Inflammatory Components of Rhododendron molle G. Don Leaf Extracts in LPS-Induced RAW 264.7.

As a traditional Chinese medicine, Rhododendron molle G. Don has a long history of treating rheumatoid arthritis. In this study, RAW 264.7 cells induced by lipopolysaccharide (LPS) were established as cell inflammatory model to evaluate the anti-inflammatory activity of chloroform extract from R. molle leaves (CERL), ethyl acetate extract from R. molle leaves (EERL) and butanol extract from R. molle leaves (BERL) and analyze the potential anti-inflammatory components of R. molle. Potential anti-inflammatory components analysis of CERL were performed by HPLC and UHPLC-Q-TOF-MS. Prediction of potential anti-inflammatory components by molecular docking experiments. Compared with negative control group, 25 μg/mL CERL could reduce the release level of NO by 62 %, and the mRNA expression levels of COX-2, IL-6, IL-1β and TNF-α were reduced by 69.74 %, 86.25 %, 77.94 % and 56.80 %, respectively. Western-Blot showed similar results. CERL, EERL and BERL exerted their inhibitory activity in dose-dependent manner. All results showed that the higher the concentration, the better the anti-inflammatory activity. CERL showed the best inhibitory activity, the second was EERL, and then was BERL. 21 terpenoids and 4 flavonoids were identified in CERL by UHPLC-Q-TOF-MS. Molecular docking results showed that triterpenoids in CERL had better interaction with target proteins (TNF-α, IL-1β). It indicated that triterpenoids may be potential anti-inflammatory components of R. molle leaves. This study explored the anti-inflammatory activities of CERL, EERL, BERL, which laid a foundation for further promoting the clinical application of R. molle.

Biosynthesis of Zinc Oxide Nanoparticles via Leaf Extracts of Catharanthus roseus (L.) G. Don and Their Application in Improving Seed Germination Potential and Seedling Vigor of Eleusine coracana (L.) Gaertn

The ecofriendly nature of materials used in synthesis and their low cost make biosynthesized nanoparticles excellent stuff for a broad range of applications in bioscience. Green nanomaterials are progressively used in agriculture to deliver plant nutrients efficiently and effectively. The present work aimed to biosynthesize zinc oxide nanoparticles (ZnO NPs) utilizing Catharanthus roseus (L.) G. Don leaf extracts to use them as a nanopriming agent for improving seed germination and seedling growth in Eleusine coracana (L.) Gaertn (finger millet). UV-Vis spectroscopy, FTIR, FE-SEM, EDX, and TEM were used to characterize biosynthesized nanoparticles (NPs). The peaks at 362 nm characterized UV-Vis spectra of ZnO NPs. The FTIR absorption spectrum of ZnO NPs showed Zn-O bending at 547 cm−1. The size (44.5 nm) and shape (nonspherical) of ZnO NPs were revealed by TEM image analysis. XRD confirmed the hexagonal wurtzite phase of ZnO with an average particle size of 35.19. The seed germination results revealed that ZnO-nanoprimed seeds at 500 mg/L substantially improved all the seed germination parameters, viz., plumule length (23.4%), radicle length (55%), vigor index (41.94%), and dry matter production (54.6%) compared to hydropriming (control).

Optimization of polyphenol extraction from Hippophae salicifolia D. Don leaf using supercritical CO2 by response surface methodology.

The online version contains supplementary material available at 10.1007/s13205-022-03358-1.

Composition phytochimique et activité antioxydante des feuilles de Combretum micranthum G. Don (Combretaceae) collectées dans les régions de Kita (Mali) et de Thiès (Sénégal)

The plant kingdom contains a very wide variety of bioactive molecules such as phenolic compounds, terpenes and alkaloids that can exhibit antioxidant properties. The objective of the present study was to determine the phytochemical composition and the antioxidant potential of Combretum micranthum G. Don leaf extracts. After botanical identification according to their organoleptic characters, leaf powder samples were submitted to phytochemical screening carried out by the characterization reactions. Also, the contents of phytochemical groups were determined by spectrophotometry. The antioxidant capacity of the leaf extracts was determined by three methods: ferric ion reducing power method and free radical scavenging methods with 2,2-diphenyl-1- picryl-hydrazyl and 2,2'-azino-bis-(3- ethylbenzothiazoline-6-sulfonic acid). The phytochemical screening showed the presence, in appreciable amount, of tannins, flavonoids, anthocyanins, alkaloids, sterols/triterpenes and saponosides in the samples. Leucoantocyanins, oses/holosides, coumarins and mucilages were found in low quantities with samples from Senegal showing the highest levels. The phytochemical group contents were: 1.127 ± 0.058 to 2.671 ± 0.031 μg/mg for alkaloids, 27.171 ± 0.005 to 48.586 ± 0.019 mg equivalent of gallic acid per gram for polyphenols, 0.713 ± 0.049 to 1.978 ± 0.068 mg equivalent of quercetin per gram dry matter for total flavonoids, 21.122 ± 0.008 to 42.024 ± 0.056 mg equivalent of tannic acid per gram for hydrolyzable tannins and 1.129 ± 0.018 to 4.354 ± 0.043 mg equivalent of catechin per gram dry matter for condensed tannins. The greatest antioxidant potential was observed with sample from Mali with inhibitory concentrations (IC50) of 502.19 ± 4.12; 6.54 ± 2.67; 491.38 ± 11.19 μg/mL respectively by DPPH•, ABTS+• and FRAP methods. This study revealed the presence of a variety of phytochemicals in leaf extracts of Combretum micranthum G.Don with high content of phenolic compounds which can be subsequently correlated to antioxidant potential of this plant.

TiO2/Co3O4 nanocomposite: Synthesis via Catharanthus roseus (L.) G. Don leaf extract, characterization and its photocatalytic activity for malachite green degradation

TiO2/Co3O4 nanocomposite was successfully synthesized using leaf extract of Catharanthus roseus (L.) G. Don. (CRE), precursors of TTIP and Co(NO3)2. FT-IR characterization shows that TiO2/Co3O4 has been formed due to the presence of secondary metabolites in CRE which have a major role as a weak base source for nanocomposite synthesis. Particle size analysis was employed by PSA and TEM, which were found to be 38.04 nm and 90.80 nm, respectively. Besides, the UV-Vis DRS result shows that TiO2/Co3O4 has bandgap energy at 2.8 eV. According to the morphological analysis, TiO2/Co3O4 nanocomposite has a spherical shape confirmed by SEM. The structural analysis was confirmed by XRD that TiO2/Co3O4 nanocompositehas a diffraction pattern combination of TiO2 and Co3O4 nanoparticle. The photocatalytic activity of TiO2/Co3O4 nanocomposite was examined for malachite green degradation. The result shows that the degradation percentage was 82.61 % under visible light illumination for 120 min.

Costus pictus D. Don leaf extract stimulates GLP-1 secretion from GLUTag L-cells and has cytoprotective effects in BRIN-BD11 β-cells

Costus pictus D. Don, commonly known as insulin plant, is a traditional Indian antidiabetic herbal medicine with glucose-lowering and insulin secretory effects having been reported in animal models and humans with Type 2 diabetes. However, its effects on GLP-1 secretion from intestinal endocrine L-cells and potential metabolic and protective effects in insulin secreting pancreatic β-cells are not yet fully understood. This study is aimed to elucidate the effects of Costus pictus D. Don leaf extract (CPE) on L-cell function and GLP-1 secretion using the established murine GLUTag L-cell model and to investigate its potential cytoprotective effects against detrimental effects of palmitate and cytokines in pancreatic β-cells using BRIN-BD11cells. Costus pictus D. Don dried leaf powder was extracted by soxhlet method. Cell viability was determined by MTT assay. Changes in gene and protein expression were quantified by qPCR and western blotting, respectively. GLP-1 and insulin secretion were measured by ELISA. CPE significantly enhanced the percentage of viable BRIN-BD11 and GLUTag cells and protected BRIN-BD11cells against palmitate- and proinflammatory cytokine-induced toxicity. CPE enhanced acute GLP-1 secretion 6.4-16.3-fold from GLUTag cells at both low (1.1mM) and high (16.7mM) glucose (P<0.01) concentrations. Antioxidant (Nrf2, Cat & Gpx1) and pro-proliferative (Erk1 and Jnk1) gene expression were upregulated by 24h culture with CPE, while proinflammatory transcription factor NF-κB was downregulated. Diminished postprandial GLP-1 secretion and loss of insulin secreting β-cells are known contributors of T2DM. Our data suggests that CPE acutely stimulates GLP-1 secretion from L-cells. Long term exposure of the BRIN-BD11cells to CPE enhances cell number and may protect against palmitate and proinflammatory cytokines by activating multiple pathways. Thus, the current study suggests that the possible antidiabetic properties of CPE may be linked to enhanced GLP-1 secretion and β-cell protection which could be beneficial in the management of T2DM.

Amelioration of antioxidant potential, toxicity, and antihyperglycemic activity of Hippophae salicifolia D. Don leaf extracts in alloxan-induced diabetic rats.

Efficacy of several plant extracts in the clinical research for modulating oxidative stress correlated with diabetes mellitus (DM) is well documented. In the present study, we investigated the in vitro antioxidant activity, toxicity, and anti-diabetic activity of methanolic extract of Hippophae salicifolia leaves in normal and alloxan-induced diabetic wistar rats. H. salicifolia leaves were found to be rich in antioxidants. The acute toxicity test of methanolic extract of H. salicifolia leaves revealed that the median lethal dose (LD50) was found to be 3.92g/kg body weight in mice. Administration of H. salicifolia leaves at 200mg/kg and 400mg/kg in alloxan-induced diabetic rats illustrated significant reduction (22% and 39%, respectively) in fasting blood glucose compared to diabetic control. Both the doses were found to be effective when compared to diabetic rats. The Hippophae-treated diabetic rats showed significant increase in the endogenous antioxidant enzymes, superoxide dismutase (50% and 74%, respectively), glutathione peroxidase (57% and 41%, respectively) and decrease in malondialdehyde (33% and 15%, respectively) levels. These results suggested that the methanolic leaf extract of H. salicifolia enhanced the antioxidant defence against reactive oxygen species produced under hyperglycaemic conditions.

Protective Effects of Solanum erianthum D. Don Leaf Extract on Lead-Induced Toxicity in Adult Wistar Rats

The possible protective effects of the most potent fraction of Solanum erianthum ethanol leaf extract on lead-induced toxicity in adult wistar rats were investigated. Phytochemical constituents, antioxidant and membrane stabilizing activities of the ethanol extract and its fractions were determined using standard procedures. Acute and sub-chronic oral toxicity studies were carried out. The blood samples, liver, and kidney were collected for the estimation of biochemical and organ parameters, and histomorphological studies. The ethyl acetate fraction had the highest antioxidant activities and high membrane stabilizing potentials when compared to the crude extract and other fractions. Significant elevations were observed in plasma albumin, creatinine and urea levels in group treated with lead only. The activities of plasma ALT and AST were significantly increased in group treated with lead alone. Treatment with ethyl acetate fraction significantly decreased (< 0.05) the elevated ALT, AST, urea and creatinine levels. The histology evidence showed progressive degeneration of the liver and kidney tissues in lead treated groups while the administration of S. erianthum showed appreciable degrees of protection to both the liver and kidney. The study concluded that ethyl acetate fraction of S. erianthum has protective effects against lead-induced toxicity in adult Wistar rats.