Phytochemical and anticonvulsant screening of three medicinal plants used in the treatment of epilepsy in the south-western part of Nigeria

The burden of epilepsy in developing countries made medicinal plants like Xylopia aethiopica fruit; Khaya grandifoliola, Alstonia boonei etc an alternative source in epilepsy management in the south-western part of Nigeria. The aim of the study was to provide pharmacological rationale for the ethnomedicinal use of the plants in epilepsy management. The oral medial lethal dose of methanol stem bark extracts of Alstonia boonei (MEAB) and Khaya grandifoliola (MEKG) and methanol fruit extract of Xylopia aethiopica (MEXAF) were done in accordance with the Organization for Economic Cooperation Development guideline. Quantitative and qualitative phytochemical profiling of the extracts was done. Anticonvulsant screening was carried out on the extracts (doses: 75, 150 and 300 mg/kg) using the pentylenetetrazole (PTZ)-induced seizure and maximum electroshock tests (MEST). Results showed that the MEXAF has the highest amount of phytochemicals except for saponins in MEKG; and MEAB with the least amount (but higher alkaloid) than MEKG. The TLC showed different bands of spots of the extracts. In the PTZ test, MEXAF showed 100 % protection against mortality at 300 mg/kg; MEAB with 66.67 % protection at 75 mg/kg and MEKG 0 % protection. MEAB, MEKG and MEXAF nonsignificantly increased the onset of seizure and latency to death. In the MEST, MEXAF, MEKG and MEAB at 75 mg/kg protected 50, 33.3 and 16.67% of the animals against tonic hind limb extension respectively and nonsignificantly (p˃0.05) decreased the recovery time at a dose of 75 mg/kg. It was concluded that the extracts possess anticonvulsant activities hence, the pharmacological credence for the ethnomedicinal use of these plants in treating epilepsy.

Phytochemical study and evaluation of the anti-inflammatory activity of some medicinal plants growing in Egypt

The anti-inflammatory activity of different extracts of five plants abundantly growing in Egypt, namely Ipomoea palmate Forsk. [Convolvulaceae], Alstonia scholaris R.Br. [Apocynaceae], Salix subserrata Willd., Salix tetrasperma Roxb, and Populus nigra Linn. [Salicaceae] has been studied. Phytochemical study on selected bioactive extracts was carried out as well as their possible mechanism of action. The results revealed a significant anti-inflammatory activity of the extracts under investigation to different degrees. A chromatographic study of the bioactive lipoidal extracts of A. scholaris and I. palmate was carried out and the results revealed the presence of unsaturated fatty acids [linoleic and linoleic]. Beta-sitosterol and campesterol were present in A. scholaris and I. palmate, respectively. Chromatographic and spectral investigation of the flavonoids in the bioactive aqueous extract of I. palmate revealed the presence of luteolin, quercetin 7-glycosie and apigenin. The anti-inflammatory activity may be due to the presence of these phytochemical constituents

Effect of Alstonia scholaris (Linn.) R. Br. on stress and cognition in mice.

Effect of stress and its modulation by methanolic extract of bark of Alstonia scholaris was studied using acute restraint stress model in mice. The extract was also evaluated for nootropic and antioxidant potential to support anti-stress activity testing. Acute restraint stress resulted in significant increase of plasma corticosterone, glucose, protein, cholesterol and triglyceride levels in stress group of animals. Methanolic extract pretreatment at 100, 250 and 500 mg/kg for 7 days displayed promising anti-stress effect by normalizing these stress-induced biochemical perturbations in plasma of mice. Effect on cognitive functions was evaluated using passive avoidance model and elevated plus maze model. Pretreatment with extract at 100, 250 and 500 mg/kg augmented acquisition and retention of memory of learned task as evidenced by increased step-down and shortened-transfer latency in passive avoidance model and elevated plus maze model, respectively. Diazepam (2 mg/kg, ip) and piracetam (200 mg/kg, po) were used as standard drugs for anti-stress and nootropic activity testing. Further, the extract at 200 microg/ml showed maximum scavenging of stable radical 1,1-diphenyl, 2-picryl hydrazyl at 90.11% and nitric oxide radical at 62.77%. The present study, thus, provided scientific support for anti-stress (adaptogenic), antioxidant and nootropic activities of methanolic extract of bark of Alstonia scholaris.

Flavonoids in leaves of Alstonia scholaris / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the flavonoids in leaves of Alstonia scholaris, an ethno-remedy of Dai People in Yunnan.</p><p><b>METHOD</b>The chemical constituents were isolated and purified by column chromatography. Their structures were elucidated on the basis of spectroscopic evidences and physicochemical properties.</p><p><b>RESULT</b>Eight flavonoids were isolated and identified as kaempferol (1), quercetin (2), isorhamnetin (3), kaempferol-3-0-beta-D-galactopyranoside (4), quercetin-3-0-beta-D-galactopyranoside (5), isorhamnetin-3-0-beta-D-galactopyranoside (6), kaempferol-3-0-beta-D-xylopyranosyl-( 2-1)-0-beta-D-galactopyranoside (7) ,quercetin-3-0-beta-D-xylopyranosyl-( 2-1)-0-beta-D-galactopyranoside (8).</p><p><b>CONCLUSION</b>Flavonoids 1-7 were isolated from A. scholaris for the first time.</p>

Formulation of the Extract of the Stem Bark of Alstonia Boonei as Tablet Dosage Form

Purpose: To formulate the extracts of the stem bark of Alstonia boonei; an important antimalarial herb; into tablet dosage form. Methods: Tablets were formulated using direct compression and wet granulation methods. The mechanical properties of the tablets were assessed using crushing strength and friability and the crushing strength:friability ratio (CSFR) while drug release properties were evaluated using disintegration and dissolution times. Results: There were statistically significant (p0.01) differences in the CSFR values and drug release properties of A. boonei tablets prepared by both methods. The differences depended on the type and concentration of excipient and binder employed in the formulation. Conclusions: The method of preparation of the A. boonei tablets needs to be carefully selected to ensure the production of tablets with adequate bond strength to withstand the rigours of handling and at the same time release the active compound (s) for biological action

Insecticidal activity of the medicinal plant, Alstonia boonei De Wild, against Sesamia calamistis Hampson / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The bioactivity of the aqueous extracts of the leaf and stem bark of the medicinal plant, Alstonia boonei De Wild (Apocyanaceae), against the pink stalk borer, Sesamia calamistis Hampson (Lepidoptera: Noctuidae) was studied in a laboratory bioassay. The extracts were incorporated into artificial diet at a rate of 0.0% (control), 1.0%, 2.5%, 5.0%, and 10.0% (w/w). Both extracts significantly (P<0.01) reduced larval survival and weight in a dose dependent manner. The concentrations that killed 50% of the larvae (LC(50)) for the stem bark extract were 2.8% and 2.1% at 10 and 20 DAI (days after introduction), respectively, while those for the leaves extract were 5.6% and 3.5%. The weights of the larvae also varied significantly (P<0.05) between the treatments in a dose dependent manner. We conclude that both leaf and stem bark extracts of A. boonei are toxic, used as growth inhibitors to S. calamistis larvae, and hold good promise for use as alternative crop protectants against S. calamistis.

Effect of Aqueous Extract of Alstonia Congensis on Glucose Transport and Na+-K+-ATPase Activity in the Everted and Non-Everted Guinea Pig Intestine and Erythrocyte Fragility

The seed of Alstonia congensis has been used as purgative by traditional doctors. It is not known if glucose transport and Na+-K+ ATPase activity are affected during the purging process. The effect of the plant on erythrocytes fragility is also not known. This study was designed to provide this information. The effect of aqueous extract (1:25w/v) of Alstonia congensis on the transportation of glucose ranging from 0.10 to 0.40M from normal and everted guinea pig intestinal strips into the surrounding 0.5M TrisEDTA saline buffer pH 8.2; on Na+-K+- ATPase activity and erythrocytes fragility were measured. Results showed that the aqueous extract reduced glucose transportation; inhibited Na+-k+-ATPase activity and specific activity at higher enzyme protein concentration and activated the enzyme activity and specific activity at lower enzyme protein concentration. Glucose transport reduction was linked to the effect of the extract on the Na+-k+-ATPase system. The extract also increased erythrocytes fragility. The active ingredient(s) in the extract is not known yet and research work is in progress to ascertain it

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.