Comparative Repellency of Selected Plants to Adult Anopheles gambiea complex (Gilles) in the Laboratory

Aims: The study evaluated the repellency effects of some tropical plants and shrubs found in semi- rural communities of Badagry Area of Lagos state; which are acclaimed to have the potentials of repelling mosquitoes from human dwellings. The repellency effects of Moringa oleifera, Morinda lucida, Magnifera indica and Phyllanthus muellerianus to adult Anopheles gambiea was evaluated in the Laboratory. Study Design: The study was carried out at Central Research Laboratory of Lagos State University, Ojo, Lagos, Nigeria and Central Research Laboratory of University of Lagos, Akoka, Lagos, Nigeria. Powdered of dried test plants were prepared and admix with coconut husk as inert, different concentrations were rubbed on the forearm of volunteers and repellency to blood starved female Anopheles mosquitoes was observed. Methodology: Test plants were collected from Badagry area of Lagos State, they were identified at University of Lagos Herbarium and given numbers. They were dried between 10 and 14 days at temperature of 25-27oC and powdered. Different concentrations of the powder mixed with powdered coconut husk was used to treat volunteers forearms and they were exposed to 0-2 two day old adult unfed mosquitoes in an aluminum glass cage fitted with net as arm entrance and repellency was observed for a period of 180 minutes, with landing counts taken every 30 minutes. The test plants were also subjected to qualitative and quantitative phytochemical analysis at University of Lagos Central Research Laboratory. Results: Results showed that all test plants were able to repel Anopheles mosquitoes in the study, repellency was shown in descending order Moringa oleifera with 88%, Magnifera indica 83%, Phyllantus muellerianuss 80% and Morinda lucida 72%. There was no statistical significance in percentage repellency at 95% CL. The result of phytochemical screening of the test plants showed that only M .indica indicated presence of saponing (36.99%). While M.oleifera has highest phenol content (45.6%3), Alkaloid (38.68%), steroid (24.89%) and Tannin (33.19%). Flavonoid and reducing sugar quantity was highest in M. indica (39.39%) and (55.18%) respectively. Conclusion: The plants were able to show repellency to Anopheles gambiae a nuisance malaria vector of serious medical importance. These plants are available in all tropical areas of Africa, they can therefore be used to prevent nuisance and painful mosquito bites which could be a sustainable way to prevent mosquito vectored diseases

Piper nigrum and Morinda lucida Possess Antioxidant Capacities and Regulate the Activities of Key Carbohydrate and Lipid Digestive Enzymes

Introduction: Carbohydrate and lipid digestive enzymes are instrumental in the absorbability of nutrients associated to diabetes and obesity. This study evaluated hydroethanolic extracts of Piper nigrum leaf and Morinda lucida stem bark for antioxidant capacity and enzymes (carbohydrate and lipid digestive) inhibition. Methods: Colorimetric assays determined enzyme (?-amylase, ?-glucosidase, lipase and cholesterol esterase) inhibition and antioxidant capacity (total phenolic (TPC) and flavonoid (TFC) content, radical scavenging activity (DPPH, ABTS), and ferric reducing antioxidant power (FRAP)) of hydroethanolic ethanolic extracts, ethyl acetate and hexane fractions. Results: At 1 mg/ml extracts of P nigrum and M lucida inhibited ?- amylase (9.82±1.05 - 36.63±0.69 %) and ?-glucosidase (22.47±0.34 - 67.77±0.58 %) activities. At 100 µg/ml extracts and fractions inhibited lipase (56.72±1.11 - 81.61±0.71 %) and cholesterol esterase (18.14 ±0.79 - 36.84±0.70 %) activities. IC50 for ?- amylase (2.20±0.02 - 7.8±1.42 mg/ml), ?-glucosidase (0.16±0.01 - 3.74±0.01 mg/ml), lipase (8.58±2.57 - 53.03±5.20 µg/ml) and cholesterol esterase (172.20±5.12 - 419.80±4.55 µg/ml) were registered. At 4 mg/ml, P. nigrum presented a higher TPC (153.78±8.31 - 354.63±6.33 mg/ml), TFC (21.65±1.14 -33.86±0.00 mg/ml) than M lucida TPC (10.21±0.11 - 169.89±6.54 mg/ml), TFC (ND - 87.32±6.14 mg/ml). P nigrum presented radical scavenging (DPPH and ABTS) activity with IC50 0.12±0.00 - 1.27±0.01 mg/ml compared to 1.31±0.02 - 3.44±0.12 mg/ml of M lucida. The FRAP IC50 values were better for P nigrum (3.38±0.14- 4.48±1.05 mg/ml) than M lucida (3.34±1.32 - 15.4±2.03 mg/ml). Conclusion: P nigrum presented better antioxidant capacity and more effective on lipid digestive enzymes while M lucida was more effective on carbohydrate digestive enzymes.

In vivo antimalarial activity of self-nanoemulsifying drug delivery systems containing ethanolic extract of Morinda lucida in combination with other Congolese plants extracts

Abstract Morinda lucida leaves are largely used by Congolese traditional healers for the treatment of uncomplicated malaria. The antimalarial activity of their ethanolic extract has been confirmed both in vitro and in vivo. However, the development of relevant formulations for potential clinical application is hampered since the active ingredients contained in this extract exhibit poor water solubility and low oral bioavailability. Hence, this work aims not only to develop self-nanoemulsifying drug delivery systems (SNEDDSs) for oral delivery of the ethanolic extract of Morinda lucida (ML) but also to evaluate its oral antimalarial activity alone and in combination with other Congolese ethanolic plant extracts (Alstonia congensis, Garcinia kola, Lantana camara, Morinda morindoides or Newbouldia laevis). Based on the solubility of these different extracts in various excipients, SNEDDS preconcentrates were prepared, and 200 mg/g of each plant extract were suspended in these formulations. The 4-day suppressive Peter's test revealed a significant parasite growth inhibiting effect for all the extract-based SNEDDS (from 55.0 to 82.4 %) at 200 mg/kg. These activities were higher than those of their corresponding ethanolic suspensions given orally at the same dose (p<0.05). The combination therapy of MLSNEDDS with other extract-based SNEDDS exhibited remarkable chemosuppression, ranging from 74.3 % to 95.8 % (for 100 + 100 mg/kg) and 86.7 % to 95.5 % (for 200 + 200 mg/kg/day). In regard to these findings, SNEDDS suspension may constitute a promising approach for oral delivery of ML alone or in combination with other antimalarial plants.

Phytochemical Analysis and Antiplasmodial (curative) Activities of Methanolic Leaf Extract of Morinda lucida (Ewe Oruwo) in Male Swiss Mice Infected with Plasmodium berghei NK65

Aim:Medicinal plants have been used for the treatment of many infections and diseases including malaria. The study was conducted to determine the effect of in vivoanti-plasmodialand antioxidant properties of the methanolic leaf extract of Morinda lucidain male Swiss albino mice infected with Plasmodium Berghei NK65. Study Design and Methodology:Phytochemical, GC-MS and AAS analyses were determined in the plant. Swiss albino mice were inoculated intraperitoneally with Plasmodium bergheiNK65. Thirty-five (35) mice were grouped into seven groups, five per group. Group A were not infected with P.bergheiNK65.Group B, C and D served as the negative and positive control groups while Group E, F and G mice were treated with 400, 600 and 800 mg/kg body weight of methanolic leaf extract of M. lucida. Haematological parameters were determined in the whole blood using BC-3200 Auto Hematology Analyzer. TP, MDA, CAT, SOD % inhibition, SOD unit and vitamin A were all determined in the liver homogenateusing standard procedures.Results:The GC-MS result of the M. lucidashows the presence of five bioactive compounds. It was also observed that the plant contains the following minerals: iron, magnesium, potassium, phosphorus and copper. Acute toxicity shows that the LD50>000mg/Kg b.wt. The extract caused 30.96%, 32.93% and 67.23% reduction in parasitemia at 400, 600 and 800 mg/kg body weight respectively while chloroquine exerted 96.53% and artesunate exerted 92.03% reduction at 10 mg/kg body weight respectively. The Haematological parameters showed that the plant extractis nothaematotoxic since it significantly (P<0.05) reduced WBC count, and increase RBC, HGB, and HCT values in the treated mice compared to the infected untreated mice. This study shows that the mean lipid peroxidation (MDA) level was significantly decreased in the malaria treated mice (group C, D, E, F and G) compared to the untreated mice (group B). There was also a significant increase in the total protein, catalase, SOD % inhibition, SOD unit and Vitamin A levels in the liver homogenate of animals treated with chloroquine, artesunate and extract of M. lucidacompared to the untreated mice. Conclusions: The study shows that Morinda lucidapossess antiplasmodial activity in male Swiss mice infected with Plasmodium berghei NK 65.

In vitro Mechanistic Assays of Tetracyclic Iridoid Compounds Isolated from Morinda lucida Benth in Leishmania species

Aims: This study investigates the activity of tetracyclic iridoid compounds against Leishmania spp. and the mechanism(s) of action. Study Design: An experimental study. Place and Duration: Department of Parasitology, Noguchi Memorial Institute for Medical Research, between September 2017 and July 2018. Methodology: The 50 % inhibitory concentration (IC50) of compounds against Leishmania donovani and L. major promastigotes were determined after 48 hours of incubation using the Alamar blue. Cytotoxicity of compounds was determined against cell lines using MTT assay. The anti-amastigote activity of compounds was further assessed by DAPI (4′,6-diamidino-2-phenylindole) staining. The mechanism of cell death induced by compounds was determined using nexin assay. Mitosis, cytokinesis and morphometry were monitored by DAPI and Kinetoplastid Membrane Protein (KMP) staining. Cell cycle arrest induced by compounds was analyzed by FACS. Results: Molucidin and ML-F52 inhibited the growth of promastigote in L. donovani (Molucidin; IC50 = 2.94±0.60 µM, ML-F52; IC50 = 0.91±0.50 µM) and L. major (Molucidin; IC50 = 1.85± 0.20 µM, ML-F52; IC50 = 1.77± 0.20 µM). ML-F52 had a 10-fold cytotoxic effect on parasites relative to normal cell lines. Against intracellular forms, Molucidin and ML-F52 inhibited intracellular amastigote replication and infectivity. Amphotericin B, Molucidin and ML-F52, induced a dose-dependent apoptotic effect on promastigotes. Although no change in KMP-11 expression was observed, iridoids inhibited cell division and morphological changes in promastigote cultures. Molucidin and ML-F52 induced apoptotic mechanism of cell death, inhibited cytokinesis and induced phenotypic changes in promastigotes. Molucidin further induced ‘’nectomonad-like’’ forms and loss of kDNA, ML-F52 induced ‘cell-rounding’ with loss of flagellum. Molucidin also induced cell growth arrest at G2-M phase (54.5 %). A significant induction of apoptosis (P = .05) was shown by an enhanced peak in the sub-G1 confirming the apoptotic inducing properties of iridoids. Conclusion: This study shows the anti-leishmania activity of tetracyclic iridoids which could be further investigated for the development of new chemotherapy against Leishmaniasis.

Evaluation of the Anti-Diabetic and Antioxidant Activities of Aqueous Extracts of Morinda lucida and Saccharum officinarum Leaves in Alloxan-Induced Diabetic Rats.

To investigate the antidiabetic, anti-hyperlipidaemic, and antioxidant potentials of the combined aqueous extracts of Morinda lucida and Saccharum officinarum leaves. Study Design: Thirty alloxan-induced diabetic male rats were randomly and evenly distributed into six groups, and were subsequently exposed to the following treatments for twenty-one days: Group I (Control): Normal saline; Group II: Untreated Diabetic control; Group III: Diabetic rats treated with glibenclamide (600mg/Kg. b.w); Group IV: Diabetic rats treated with Morinda lucida (400mg/Kg b.w); Group V: Diabetic rats treated with Saccharum officinarum (400mg/Kg b.w); Group VI: Diabetic group treated with Morinda lucida and Saccharum officinarum (400mg/Kg b.w, 1:1). Place and Duration of Study: This work was carried out in the Department of Biochemistry, University of Lagos, Lagos, Nigeria between November 2012 and February 2013. Methodology: Blood samples were collected for the determination of fasting blood sugar and biochemical profiles following the last oral treatment and an overnight fast. The pancreas, liver, and kidney tissues of each animal were excised and subjected to tests for oxidative stress markers. Result: There was a significant reduction (P< 0.001) in the fasting blood glucose of diabetic rats treated with the plant extracts, both separately and the extract mixture when compared to the untreated diabetic group. Diabetic treated groups showed a significant decrease (P<0.001) in the levels of Total cholesterol and Low Density Lipoprotein Cholesterol when compared to the diabetic untreated group. Levels of reduced glutathione and Catalase activities in the pancreas and liver of diabetic treated groups were significantly increased compared to the untreated diabetic control (P<0.001). Activities of Super-Oxide Dismutase were significantly increased (P<0.001) in the pancreas and kidney of rats treated with the plant extracts while Malondialdehyde showed a significant reduction in the treated groups of all organs evaluated (P<0.001). Conclusion: The extracts showed anti-hyperglycaemic, anti-hyperlipidaemic and antioxidant potentials.

Assessment of the prophylactic efficacy of a crude aqueous extract of morinda lucida leaves on plasmodium falciparum infection of albino rats.

A study on the prophylactic efficacy of a crude aqueous extract of the leaves of Morinda lucida on plasmodium falciparum was carried out using sixteen albino rats grouped into curative, suppressive, prophylactic and control ;A,B,C and D respectively. The rats were inoculated with the parasites and allowed for 21days before 2mls of the extract was administered to each of the rats in group A twice daily for 3days, and for group B, 2mls was administered just once, 3hours before scarifying them, while for group C, 2mls was given twice daily for 3days before inoculation with the parasites, but group D were not given the extract. The results showed that the extract cleared the parasites in group A rats and did not allow its growth in group C rats, but did not suppress it in group B rats, while the control showed the ability of the parasites surviving in the rats. There was a significant at (P< 0.05) weight loss by the rats in all the groups, following the inoculation of the parasite. It can be inferred therefore, that a crude aqueous extract of Morinda lucida has a prophylactic efficacy in addition to its curative activity against plasmodium parasites and could be used to mitigate the impact of plasmodium parasites.

Antihemolytic Properties of Extracts of Six Plants Used in the Traditional Treatment of Sickle Cell Disease in Benin.

This study is focused on the in vitro evaluation of the hemolysis inhibitory activity of aqueous extracts of six plants used in the traditional treatment of sickle cell disease in Benin: Morinda lucida, Uvaria chamae, Lonchocarpus cyanescens, Croton zambesicus, Raphiostylis beninensis and Xylopia aethiopica. AS and SS red blood cells are subjected to hyposmotic impact with decreasing concentrations of NaCl solution. All the aqueous extracts of the six plants showed a better contribution in erythrocyte osmotic resistance from the concentration of 5 mg/mL to 1 mg/mL, except the extract at 5 mg/mL of Raphiostylis beninensis that caused hemolysis of both red blood cells AS and SS. The extract at 1 mg/mL of Raphiostylis beninensis and the extracts at 5mg/mL of Xylopia aethiopica and Croton zambesicus showed a high hemolysis inhibition of red blood cells AS and SS. The extracts of Lonchocarpus cyanescens showed moderate hemolysis inhibition of SS red blood cells while extracts of Uvaria chamae inhibited highly the hemolysis of AS red blood cells. As for the roots of Morinda lucida, only the extract at 5mg/mL highly inhibited the hemolysis of the AS red blood cells. This protocol seems appropriate to work with both AS and SS blood because the comparative effects of each tested extract on hemolysis of AS and SS blood showed a good correlation coefficient of Pearson (1 or -1). All the plants tested in this work showed, at different doses, an in vitro antisickling effect and this explains partially their use in the traditional treatment of sickle cell disease.