Total polyphenols and antihyperglycemic activity of aqueous fruits extract of Abelmoschus esculentus: Modeling and optimization of extraction conditions

Genome architecture and genetic diversity of allopolyploid okra (Abelmoschus esculentus)

The allopolyploid okra (Abelmoschus esculentus) unveiled telomeric repeats flanking distal gene-rich regions and short interstitial TTTAGGG telomeric repeats, possibly representing hallmarks of chromosomal speciation. Ribosomal RNA (rRNA) genes organize into 5S clusters, distinct from the 18S-5.8S-28S units, indicating an S-type rRNA gene arrangement. The assembly, in line with cytogenetic and cytometry observations, identifies 65 chromosomes and a 1.45 Gb genome size estimate in a haploid sibling. The lack of aberrant meiotic configurations implies limited to no recombination among sub-genomes. k-mer distribution analysis reveals 75% has a diploid nature and 15% heterozygosity. The configurations of Benchmarking Universal Single-Copy Ortholog (BUSCO), k-mer, and repeat clustering point to the presence of at least two sub-genomes one with 30 and the other with 35 chromosomes, indicating the allopolyploid nature of the okra genome. Over 130 000 putative genes, derived from mapped IsoSeq data and transcriptome data from public okra accessions, exhibit a low genetic diversity of one single nucleotide polymorphisms per 2.1 kbp. The genes are predominantly located at the distal chromosome ends, declining toward central scaffold domains. Long terminal repeat retrotransposons prevail in central domains, consistent with the observed pericentromeric heterochromatin and distal euchromatin. Disparities in paralogous gene counts suggest potential sub-genome differentiation implying possible sub-genome dominance. Amino acid query sequences of putative genes facilitated phenol biosynthesis pathway annotation. Comparison with manually curated reference KEGG pathways from related Malvaceae species reveals the genetic basis for putative enzyme coding genes that likely enable metabolic reactions involved in the biosynthesis of dietary and therapeutic compounds in okra.

The effect of Abelmoschus esculentus L. (Okra) extract supplementation on glycaemic control, inflammation, kidney function and expression of PPAR-α, PPAR-γ, TGF-β and Nrf-2 genes in patients with diabetic nephropathy: a triple-blind, randomised, placebo-controlled trial

The present study was carried out to evaluate the effects of okra extract supplementation on kidney function, glycaemic control, inflammation and gene expression in patients with diabetic nephropathy (DN). A total of sixty-four DN patients based on the inclusion and exclusion criteria were recruited in this triple-blind placebo-controlled randomised clinical trial. Participants were randomly allocated to receive a 125-mg capsule of dried okra extract (DOE) (n 32) or placebo (n 32) for 10 weeks. At the baseline and endpoint of the trial, kidney function, glycaemic indices, inflammation and gene expression were evaluated. Statistical analysis showed that fasting blood glucose, HbA1c and insulin resistance significantly reduced in the DOE group although between-group analysis did not show any significant difference. Also, no significant difference was observed in urine protein, urine creatinine and high-sensitivity C-reactive protein between the two groups. Furthermore, gene expression of PPAR-α, PPAR-γ, transforming growth factor-beta and Nrf-2 did not affect the end of the trial in comparison with the baseline. According to the present study, DOE did not have impressive effects on kidney function, inflammation, glycaemic management and gene expression in patients with DN.

An interpenetrating polymer networks based on polydivinylbenzene/aminated polyglycidyl methacrylate with better decolorization performance toward reducing sugar solution

The separation of valuable sugar components from a xylose mother liquor (XML) requires a pre-decolorization over a resin, however the market-available resins show a low performance. To overcome this drawback, an interpenetrating polymer network (IPN) resin was designed for efficiently removing the non-sugar impurities from an XML. The prepared IPN resin showed good decolorization performance for the XML, and the decolorization effect of the XML on the resin modified with a short-chain amination reagent was better. The adsorption capacity of the resin for phenols was significantly improved after an amination-modification, but that for furfural remained constant. The theoretical study confirmed that good decolorization effect of the XML on that resin was mainly ascribed to the synergistic action of adsorption forces, such as π-π stacking and hydrogen bonding.

Clinical efficacy and safety of okra (Abelmoschus esculentus (L.) Moench) in type 2 diabetic patients: a randomized, double-blind, placebo-controlled, clinical trial

AIMS

The recent trend toward the use of natural functional and medical supplements has motivated the focus on the search and revival of traditional medicinal plant applications for many years. As a valuable dietary crop, okra fruit (Abelmoschus esculentus (L.) Moench) has been used for thousands of years as a medicinal food. This clinical trial aimed to assess the efficacy and safety of the okra pod capsule as an adjuvant treatment in controlling type 2 diabetes mellitus and provide clinical trial-based evidence about its anti-inflammatory effects.

METHODS

A total of 100 type II diabetic patients, aged between 40 and 60 years, were randomly assigned into two groups of okra and placebo. The first group was administered 1000 mg of powdered okra fruit three times a day for 3 months, while the other group received a placebo capsule with the same dosage. Both groups continued the standard antidiabetic therapy (consisting of metformin and gliclazide, as well as a nutritional regimen). At the start and three months later, various factors were measured, including FBG, insulin, HbA1c, cholesterol, triglycerides, HDL, LDL, CRP, liver and renal function tests, blood pressure, and BMI changes.

RESULTS

According to the results, patients who received okra treatment exhibited a significant decrease in FBG, HbA1c, total cholesterol, and triglyceride levels when compared to both the baseline and the placebo group. Patients in the okra group have lower levels of hs-CRP compared with the placebo group after 3 months of treatment. No liver, kidney, and blood pressure or other side effects were observed in the groups associated with okra treatment.

CONCLUSIONS

The present study demonstrated that adjunctive consumption of okra, in type 2 diabetic patients with 1000 mg three times a day for three months, improves lipid profile, glycemic control, and chronic inflammation without any tangible adverse effects.

CLINICAL TRIAL REGISTRY

IRCT.Ir (IRCT20120112008712N2). https://www.irct.ir/trial/42042 .

Antibacterial and phytochemical analysis of traditional medicinal plants: An alternative therapeutic Approach to conventional antibiotics

The purpose of this study was to carry out antibacterial and phytochemical analyses on six selected medicinal plants that have been traditionally used by the local people to treat and control different diseases. The antibacterial activities of methanolic extracts of these plants were assessed using the Agar well diffusion and Microtiter broth dilution methods. The root extract of Andrachne aspera showed significantly (p < 0.05) highest mean zone of inhibition at concentrations of 100 mg/ml (33 ± 0.17) and 200 mg/ml (33.5 ± 0.84) against S. epidermidis. The second highest mean zone of inhibition (24.8 ± 0.41) was recorded by Dichrostachys cinerea leaf extract against S. epidermidis at 200 mg/ml concentration. The minimum inhibitory concentrations 1.0 ± 0.0 was recorded by Andrachne aspera against E. faecalis and 2.0 ± 0.0 against S. aureus by Dichrostachys cinerea. The preliminary phytochemical analysis showed that Andrachne aspera and Dichrostachys cinerea contained strong concentration of Polyphenols and Flavonoids. Therefore, these two medicinal plant species have promising potential for further detailed investigations, including safety tests, characterization and isolation of bioactive secondary metabolites for the development of alternative drugs.

Ethnomedicinal Knowledge of Plants Used in Nonconventional Medicine in the Management of Diabetes Mellitus in Kinshasa (Democratic Republic of the Congo)

Background

People with diabetes, herbalists, and traditional medicine practitioners (TMPs) from Kinshasa use plants to treat diabetes, but no study has inventoried the plants used by these populations. The present study was conducted to identify the plants used in Kinshasa to treat diabetes mellitus.

Methods

The survey conducted in the form of a semistructured interview between March 2005 and August 2006 made it possible to collect ethnobotanical information from people with diabetes (n = 126), herbalists (n = 80), and TMPs (n = 120).

Results

The 326 subjects consulted (sex ratio M/F = 0.6, age 51 ± 7 years, and experience: 17 ± 5 years) provided information on 71 plants, most of which are trees (35%), belonging to 38 families dominated by Fabaceae (19.7%) and indicated in 51 other cases of consultation dominated by malaria (12%). From these 71 plants derived, 86 antidiabetic recipes were administered orally, where the leaf is the most used part (>50%) and the decoction (>46%) is the most common mode of preparation. This study reports for the first time the antidiabetic use of 11 species, among which Tephrosia vogeliiX (0.08), Chromolaena corymbosaX (0.06), and Baphia capparidifoliaX (0.06) present the highest consensus indexes (CI) and Marsdenia latifoliaW (UVp = 0.08) and Rauvolfia manniiX (UVp = 0.06) present the highest UVs.

Conclusion

The results show that Kinshasa people treat diabetes using several plants. Some are specific to the ecological environment; others are used in other regions. Pharmacological studies are underway to assess the therapeutic efficacy of these plants.

A Review: Pharmacological Activity and Phytochemical Profile of Abelmoschus esculentus (2010-2022)

Abelmoschus esculentus L. Moench (okra) which belongs to the family Malvaceae is a commonly consumed vegetable that consists of the seed component which is rich in polyphenolic compounds. The aim of this study is to highlight the chemical and biological diversity of A. esculentus. This plant contains many vitamins, minerals, proteins and carbohydrates in addition to flavonoids, terpenes, phenolic compounds and sterols. These variations in the chemical composition resulted in different therapeutic activities including antidiabetic, hypolipidemic, antioxidant, antimicrobial, anticancer, wound healing, hepatoprotective, immunomodulator, neuroprotective, and gastroprotective activities in addition to cardioprotective activity.

Metabolomics and transcriptomics strategies to reveal the mechanism of diversity of maize kernel color and quality

BACKGROUND

Maize has many kernel colors, from white to dark black. However, research on the color and nutritional quality of the different varieties is limited. The color of the maize grain is an important characteristic. Colored maize is rich in nutrients, which have received attention for their role in diet-related chronic diseases and have different degrees of anti-stress protection for animal and human health.

METHODS

A comprehensive metabolome (LC-MS/MS) and transcriptome analysis was performed in this study to compare different colored maize varieties from the perspective of multiple recombination in order to study the nutritional value of maize with different colors and the molecular mechanism of color formation.

RESULTS

Maize kernels with diverse colors contain different types of health-promoting compounds, highlighting that different maize varieties can be used as functional foods according to human needs. Among them, red-purple and purple-black maize contain more flavonoids than white and yellow kernels. Purple-black kernels have a high content of amino acids and nucleotides, while red-purple kernels significantly accumulate sugar alcohols and lipids.

CONCLUSION

Our study can provide insights for improving people's diets and provide a theoretical basis for the study of food structure for chronic diseases.

Optimization of near-infrared reflectance models in determining flavonoid composition of okra (Abelmoschus esculentus L.) pods

Okra pods have been utilized as a functional food due to their rich active ingredient composition, especially the high content of flavonoid compounds. This study conducted near-infrared spectroscopy (NIRS) modeling optimization and external validation based on the flavonoid components of 219 pod samples. Spectral correlation analyses identified two types of spectral response patterns classified as quercetin-3-O-xylose (1-2) glucoside (QOXG) and total flavonoid content (TFC), consisting of six different spectral regions. Different modeling effects were observed for QOXG and TFC with various spectral region combination analyses, where the lower wave-number region contributed more to both flavonoids calibration models. The combination of standard normal variate / "1, 9, 3" / partial least squares was found to be the most effective for developing calibration models for both flavonoids. The resulting models had small root mean square errors of prediction for external validation and high determination coefficients, indicating their usefulness for rapid prediction of flavonoid composition in okra pods.

Onopordum acanthium L. extract attenuates pancreatic β-Cells and cardiac inflammation in streptozocin-induced diabetic rats

BACKGROUND AND OBJECTIVE

Methanolic extract from Onopordum acanthium L. leaves (MEOAL) has been discovered to treat diabetic complications. The objective of this study is to evaluate the ameliorative role of MEOAL on pancreatic islet injury and myocardial inflammation in diabetic rats.

METHODS

Forty male Wister albino rats were allocated into five groups of eight rats each. Group A was the negative control group. Single intraperitoneal injection of streptozocin (50mg/kg) were used for the four experimental groups. Group B served as the positive control group. The rats in Groups C, D, and E received glibenclamide (5mg/kg), MEOAL (200, and 400 mg/kg) respectively, for eight weeks. Group C served as the standard drug group. High performance liquid chromatography (HPLC) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assays for antioxidant activity were conducted in MEOAL. In silico study, calculation of molecular binding energy (DG), and inhibition constant (pKi) of bioactive constituents in MEOAL were performed.

RESULTS

Administration of MEOAL significantly increases insulin content in β-cells with a marked enhancement of pancreatic islet structure, resulting in a significant reduction of blood glucose level and body weight loss. MEOAL treatment suppressed the increase of inflammatory cell score in myocardial tissue with an elevation of M2 -like macrophage. The phytochemical studies recorded the presence of six polyphenols, including catechin, kaempferol, syringic acid, p-coumaric acid, epicatechin and gallic acid in MEOAL. Moreover, the antioxidant activity of the extract was greater than that of standard ascorbic acid. The docking studies of the ligands Catechin, kaempferol and epicatechin with proteins showed high affinities with various targets related in β-Cells and cardiac inflammation.

CONCLUSIONS

The attenuation of pancreatic β-Cells damage and cardiac inflammation by MEOAL could be attributed to the presence of Catechin, kaempferol and epicatechin which have high affinities with the receptors namely pancreatic alpha-amylase, glucokinase, COX-2, and COX-1.

Antioxidant and antidiabetic activities of a polyphenol rich extract obtained from Abelmoschus esculentus (okra) seeds using optimized conditions in microwave-assisted extraction (MAE)

Functional foods have gained popularity in recent decades. They are exploited for their bioactive compounds like polyphenols, which are highly demanded in cosmetic, pharmaceutical and nutraceutical industries. However, extractive techniques and conditions used up to recently are almost obsolete and must be optimized for higher efficiency. The current study aimed to evaluate the antidiabetic potential of an optimized extract of Abelmoschus esculentus (okra) seeds. The optimal conditions for extracting polyphenolic compounds from okra seeds were determined using Microwave Assisted Extraction (MAE). A Face Center Composite Design (FCCD) was used for optimization. Solvent/dry matter ratio, wavelength and time were considered while the response studied was the polyphenolic content. The extract obtained at optimal conditions was characterized using Thin Layer Chromatography (TLC) and Fourier Transform Infra-Red (FTIR) spectroscopy, then tested for its antioxidant, alpha amylase inhibitory and antidiabetic activities. Response Surface Methodology (RSM) permitted the determination of the optimal conditions for phenols extraction as: microwave power 330 W, with a solvent ratio of 97.04/1 mL/g for 9.5 min of extraction time. The optimized extract showed a phenolic content up to 86.37 ± 1.13 mg GAE/g containing quercetin and catechin as revealed by the TLC. Functional groups characteristic of polyphenols were identified on FTIR spectra, and the extract exhibited good in vitro antioxidant capacities with DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging capacity and FRAP (Ferric Reducing Antioxidant Power Assay). An IC50 of 3.99 ± 0.15 μg/mL was obtained with the DPPH scavenging test. Alpha amylase inhibitory assay revealed that the optimized okra extract behaved as a non-competitive inhibitor of porcine pancreatic amylase with an IC50 of 484.17 ± 2.33 μg/mL. Antidiabetic activity of the extract was observed in streptozotocin-induced diabetic males Wistar rats, as shown by the fasting blood glucose levels, food intake, changes in body weight and serum lipid profile among others.

Investigation of Antioxidant, Hypoglycemic and Anti-Obesity Effects of Euphorbia Resinifera L

Objectives

The aim of this work is to evaluate the in vitro antioxidant, hypoglycemic, and antiobesity effects of Euphorbia resinifera extracts and investigate the phenolic constituents and the toxicity of these extracts.

Methods

Phytochemical screening was performed to detect polyphenols and flavonoids. Antioxidant activity was evaluated by four methods (DPPH, ABTS, H₂O₂, and xanthine oxidase inhibition). The hypoglycemic effect was determined by the inhibition of α-amylase and α-glucosidase enzymes in vitro and via a starch tolerance study in normal rats. The antiobesity effect was estimated by in vitro inhibition of lipase.

Results

Phytochemical screening revealed that the ethanolic extract was rich in polyphenols (99 ± 0.56 mg GEA/g extract) and tannins (55.22 ± 0.17 mg RE/g extract). Moreover, this extract showed higher antioxidant activity in different tests the DPPH assay (IC₅₀ = 53.81 ± 1.83 µg/mL), ABTS assay (111.4 ± 2.64 mg TE/g extract), H₂O₂ (IC₅₀ = 98.15 ± 0.68 µg/mL), and xanthine oxidase (IC₅₀ = 10.26 ± 0.6 µg/mL). With respect to hypoglycemic effect, the aqueous and ethanolic extracts showed IC₅₀ values of 119.7 ± 2.15 µg/mL and 102 ± 3.63 µg/mL for α-amylase and 121.4 ± 1.88 and 56.6 ± 1.12 µg/mL for α-glucosidase, respectively, and the extracts lowered blood glucose levels in normal starch-loaded rats. Additionally, lipase inhibition was observed with aqueous (IC₅₀ = 25.3 ± 1.53 µg/mL) and ethanolic (IC₅₀ = 13.7 ± 3.03 µg/mL) extracts.

Conclusion

These findings show the antioxidant, hypoglycemic, and hyperlipidemic effects of E. resinifera extracts, which should be investigated further to validate their medicinal uses and their pharmaceutical applications.

Intervention Effects of Okra Extract on Brain-Gut Peptides and Intestinal Microorganisms in Sleep Deprivation Rats

Objective

Okra, possessing various bioactive components, is used to treat different diseases. This study sought to estimate the intervention effects of okra extract (OE) on brain-gut peptides (BGPs) and intestinal microorganisms in sleep deprivation (SD) rats.

Methods

SD rat models were established using the modified multiple platform method and then treated with normal saline, diazepam tablets, or different doses of OE. Body weight and average daily water consumption of rats were recorded. Depressive behaviors of rats were assessed by the open field test and sucrose preference test. Serum levels of noradrenaline, melatonin, inflammatory factors (IL-1β/IL-6/TNF-α/IL-4/IL-10), and BGP indexes, including gastrin (GAS), motilin (MTL), 5-hydroxytryptamine (5-HT), cholecystokinin (CCK), and vasoactive intestinal peptide (VIP) were measured by ELISA. Additionally, the DNA relative contents of representative intestinal microorganisms in the collected rat feces were determined using RT-qPCR.

Results

SD decreased body weight and average daily water consumption and induced depressive behaviors as well as stress and inflammatory responses in rats. SD rats exhibited lowered GAS, MTL, 5-HT, and VIP but elevated CCK and showed diminished DNA relative contents of Bacteroidetes and probiotics (Bifidobacteria and Lactobacilli) but increased Clostridium perfringens. OE at different doses ameliorated the depressive behaviors and mitigated the stress and inflammatory responses in SD rats, raised the serum contents of GAS, MTL, 5-HT, and VIP, reduced CCK level, elevated the DNA relative contents of Bacteroidetes and probiotics, but diminished Clostridium perfringens. OE exhibited similar intervention effects to diazepam tablets (positive control).

Conclusion

OE exerts intervention effects on BGPs and intestinal microorganisms in SD rats.

Hypoglycemic, Antihyperglycemic, and Toxic Effects of Physalis peruviana L. Aqueous and Methanolic Leaf Extracts in Wistar Rats

Background

Physalis peruviana L. (Solanaceae) is a plant widely used in traditional medicine systems to manage various diseases, including diabetes mellitus, which remains a global health problem in developing and developed countries. This study aimed to scientifically evaluate its antidiabetic bioactivity and short-term toxicity in rats.

Methods

We prepared various doses (100, 200, 400 mg/kg) of aqueous and methanolic leaf extracts for the antidiabetic study, and a dose of 2000 mg/Kg was prepared for the acute toxicity test. The first group that evaluated the hypoglycemic effect consisted of forty normoglycemic Wistar rats aged 7–8 months old with a weighted average of 265.8 ± 24.6 g. The second group consisted of intraperitoneal glucose-loaded male animals to evaluate the antihyperglycemic effect. The third group contained two groups of normoglycemic female rats (n = 3), aged 3 and 4 months old (weight average: 187.45 ± 14.82 g), treated for 14 days with aqueous and methanolic extracts (2 g/kg b.w) to assess mortality and toxic effects. Blood samples were taken at 30, 60, 90, and 120 min post-treatment in hypoglycemic and antihyperglycemic evaluations. Glibenclamide (5 mg/kg) was used as a reference drug. The control animals in each group did not receive the extracts.

Results

In hypoglycemic rats, 100 mg/kg of aqueous and methanolic extracts significantly lowered the fasting blood glucose level by 13.92% (p < 0.0001) and 21.95% (p < 0.01), respectively, compared to the control group. In glucose tolerance test group, methanolic extracts significantly reduced hyperglycemia by 54.55% (p < 0.0001), 46.50% (p < 0.0001), 39.78% (p < 0.0001) at 400, 200 and 100 mg/kg b.w, respectively, compared to control; aqueous extract 400 mg/kg reduced hyperglycemia by 39.44% (p < 0.05). At the 2000 mg/kg dose, leaf aqueous and methanolic extracts did not show any signs of intoxication and mortality.

Conclusion

Crude aqueous and methanolic leaf extracts of P. peruviana ambrosioides appeared safe at 2000 mg/kg and have bioactivity in controlling the blood glucose levels, supporting their use in treating diabetes.

Abelmoschus esculentus (L.) Moench Pod Extract Revealed Antagonistic Effect against the Synergistic Antidiabetic Activity of Metformin and Acarbose upon Concomitant Administration in Glucose-Induced Hyperglycemic Mice

Abelmoschus esculentus (L.) Moench, commonly known as okra, is one of the most widely used vegetable crops currently used for diabetes treatment as well. It is thought that the large amount of soluble dietary fibers present in okra is responsible for the slowing of the absorption of glucose from the gut. However, its role in concomitant administration with commonly prescribed medications, including metformin (MET) and acarbose (ACR) for diabetes, is unclear. Therefore, this study assessed the effect of A. esculentus pod extract (AEE) administered concomitantly with MET and ACR in the glucose-induced hyperglycemic mice model. The AEE was prepared using green okra pods. In this experiment, each male Swiss Webster mouse was administered a 2.5 gm/kg/BW dose of glucose via gastric lavage to induce hyperglycemia. The experimental animals were divided into five groups: (i) negative control, (ii) positive control, (iii) MET only, (iv) MET and ACR, and (v) MET, ACR, and AEE. The orally administered doses of the MET, ACR, and the extract were 150 mg/kg/BW, 15 mg/kg/BW, and 0.2 mL/kg/BW, respectively. We found that MET only and a combination of MET and ACR reduced glucose levels significantly (p < 0.01) compared to the positive control. On the other hand, when MET, ACR, and AEE were administered simultaneously, the synergistic antihyperglycemic action of the MET and ACR was diminished. After 150 min, the blood glucose level was 4.50 ± 0.189 mmol/L (iv) and 6.58 ± 0.172 mmol/L (v). This study suggests that taking AEE concurrently with MET and ACR would reduce the effectiveness of antidiabetic drugs; thereby, concomitant administration of these antidiabetic agents is not recommended. This study provides an essential basis for decision-making about the consumption of AEE with conventional medicine. Further study is required to find the molecular insight of drug interactions in combination therapy of medicinal plants for diabetes.

Effects of the Oral Administration of Aqueous and Methanolic Leaf Extracts of Chenopodium ambrosioides L. (Amaranthaceae) on Blood Glucose Levels in Wistar Rats

Background

Diabetes mellitus is a metabolic disorder that poses a major global health threat. The current diabetes mellitus uses insulin and oral hypoglycemic agents, which have limitations, including adverse effects and secondary failures. Herbal medicine is being evaluated for its role in the pharmacotherapy of diabetes. This study was aimed to assess the anti-diabetic potential and short-term toxicity level of Chenopodium ambrosioides collected from Bukavu in Democratic Republic of Congo.

Methods

Leaves of C. ambrosioides were extracted by infusion and maceration with distilled water and 95% methanol, respectively. Hypoglycemic and antihyperglycemic potentials of the aqueous and methanolic were investigated in normoglycemic and intraperitoneal glucose-loaded rats at 100, 200, and 400 mg/kg body weight. An oral acute toxicity test was carried out on healthy female Wistar rats.

Results

Acute toxicity test showed the mean lethal dose (LD₅₀) for both aqueous and methanol extracts of C. ambrosioides to be more than 2000 mg/kg. The group treated with glibenclamide (5 mg/kg b.w) and aqueous extract of the plant (200 mg/kg b.w) showed a significant reduction (p< 0.0001 and p< 0.05) of fasting blood glucose by 46.91% and 16.72%, respectively, compared to control and all other treatment groups. In acute conditions, a single oral administration of the aqueous and methanolic extracts lowered fasting blood glucose in rats. Any manifestation and signs of toxicity and mortality have been recorded for 14 days of observation.

Conclusion

Leaf aqueous and methanolic extracts of C. ambrosioides appeared safe at 2000 mg/kg. The plant demonstrated some anti-diabetic potential in rats, explaining its use as an anti-diabetic remedy locally.

Phytochemical Screening and Antioxidant Activity of Seven Native Species Growing in the Forests of Southern Chilean Patagonia

The genus Nothofagus is one of the most abundant in the subantarctic Patagonian forests. Five species inhabit these ecosystems, three evergreen (Nothofagus betuloides, Nothofagus dombeyi, and Nothofagus nitida) and two deciduous (Nothofagus pumilio and Nothofagus antarctica). This is the first report on the levels of secondary metabolites and the antioxidant capacity of Patagonian tree species growing in natural environments. The aim of this work was to carry out a phytochemical screening, to determine the antioxidant capacity, the sun protection factor, and the α-glucosidase and tyrosinase inhibitory activity of foliar extracts of the five previous species. Besides, Aristotelia chilensis and Berberis microphylla, two species of Patagonian shrubs growing in the same forests, were used as reference. N. dombeyi was the Nothofagus with the best antioxidant capacity. B. microphylla differed from all studied species. Moreover, the Nothofagus was split into two groups. N. betuloides and N. dombeyi are the most similar species to A. chilensis. The α-glucosidase was completely inhibited by all studied extracts. Furthermore, N. antarctica, N.pumilio, and N. nitida inhibited about 70% of the tyrosinase activity. All the results found in this study for the species of the genus Nothofagus support further research on their potential beneficial properties for human health.

Developmental stages influence in vivo antimalarial activity of aerial part extracts of Schkuhria pinnata

ETHNOPHARMACOLOGICAL RELEVANCE

Malaria remains a dire health challenge, particularly in sub-Saharan Africa. In Uganda, it is the most ordinary condition in hospital admission and outpatient care. The country's meager health services compel malaria patients to use herbal remedies such as Schkuhria pinnata (Lam.) Kuntze ex Thell (Asteraceae). Although in vivo studies tested the antimalarial activity of S. pinnata extracts, plant developmental stages and their effect at different doses remain unknown.

AIM OF THE STUDY

This study aims to determine the effect of the plant developmental stage on the antimalarial activity of S. pinnata in mice and to document the acute oral toxicity profile.

METHODS

Seeds of S. pinnata were grown, and aerial parts of each developmental stage were harvested. Extraction was done by maceration in 70% methanol. The antimalarial activity was evaluated using chloroquine-sensitive Plasmodium berghei on swiss albino mice, in a chemosuppressive test, at 150, 350, and 700 mg/kg, p.o. Standard drugs used were artemether-lumefantrine (0.57 + 3.43) mg/kg and chloroquine (10 mg/kg) as positive controls. Distilled water at 1 mL/100g was used as a negative control. The Lorke method was adopted to determine the acute toxicity of extracts.

RESULTS

The flowering stage extract had a maximum suppression of parasitemia at 700 mg/kg (68.83 ± 4.49%). Extract at other developmental stages also significantly suppressed the parasitemia (in the ascending order) fruiting (50.71 ± 1.87%), budding (54.92 ± 7.56%), vegetative (55.39 ± 2.01%) compared to the negative control (24.7 ± 2.7%), p < 0.05. Extracts from all developmental stages increased survival time, with the flowering stage having the highest survival time at 20.33 ± 0.88 days. All extracts had an LD₅₀ of 2157 mg/kg, implying that extracts are safe at lower doses.

CONCLUSION

Together, our findings revealed that the S. pinnata extracts at the flowering stage had superior antimalarial activity compared to other plant developmental stages. Extracts from all developmental stages have demonstrated a dose-dependent suppression of malarial parasites and increased survival time with an LD₅₀ of 2157 mg/kg. Thus, for better antimalarial activity, local communities could consider harvesting S. pinnata at the flowering stage. Further studies are needed to isolate pure compounds from S. pinnata and determine their antimalarial activity.