Open Access Original Research Article

Identification and Molecular Characterization of Candidatus Liberibacter asiaticus (Citrus Huanglongbing Disease Pathogenic Agent) and Its Control by Plant Extracts in Bangladesh

Habiba ., Md. Firose Hossain, Junaite Bin Gias Uddin, Asura Khanam Lisa, Md. Asadul Islam, Biswanath Sikdar

European Journal of Medicinal Plants, Page 1-13
DOI: 10.9734/EJMP/2018/40298

Aims: To identify and characterize Citrus Huanglongbing disease causing pathogen Candidatus Liberibacter asiaticus and to evaluate its biological control using medicinal plant extracts.

Study Design: The study was designed based on standard laboratory protocol.

Place and Duration of Study: Professor Joarder DNA and Chromosome Research Lab, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi-6205, Bangladesh between June 2015 and September 2016.

Methodology: Causal pathogen of Citrus Huanglongbing disease was isolated from infected leaves. Different types of biochemical and morphological characterizations of Candidatus Liberibacter asiaticus were done. 16S rDNA primers (27F and 1391R) were used to amplify genomic DNA of Candidatus Liberibacter asiaticus. Sequencing of 16S rDNA sequence of Candidatus Liberibacter asiaticus were performed. Sensitivity pattern of Candidatus Liberibacter asiaticus against several standard antibiotics were done. Antimicrobial activity test was observed using two solvents extracts of four medicinal plants by disc diffusion method in vitro condition.

Results: Candidatus Liberibacter asiaticus showed positive and negative response to different biochemical test. Candidatus Liberibacter asiaticus showed gram negative in gram staining test. Candidatus Liberibacter asiaticus showed highest 35±0.5 mm and lowest 8±0.2 mm zone of inhibition against amoxycillin and kanamycin respectively. Approximately 1300bp band was found in PCR amplification and phylogenetic tree analysis of 16S rRNA gene sequence of Candidatus Liberibacter asiaticus showed 75% similarity with Candidatus Liberibacter asiaticus strain 374.15. Candidatus Liberibacter asiaticus showed highest 16±0.5 mm diameter of zone of inhibition at 60 µg/ml concentration for ethanol extract of Cuscuta reflexa.

Conclusion: This study will be helpful for proper identification, characterization and control of Citrus Huanglongbing disease causing pathogen Candidatus Liberibacter asiaticus in an eco-friendly way.

Open Access Original Research Article

Phytochemical Screening and Synergistic Anti-proliferative Activity against Selected Cancer Cell Lines of Moringa oleifera and Indigofera arrecta Leaf Extracts

Jecinta Wanjiru Ndung’u, Edward Anino, Douglas Kahura Njuguna, Reginah Mwangangi, Mercy Jepkorir, Regina Wachuka Mbugua, Jean Chepng’etich, Chrispus Mutuku Ngule, Peter Mwitari

European Journal of Medicinal Plants, Page 1-11
DOI: 10.9734/EJMP/2018/41021

Medicinal plants present a plausible source for anticancer agents. Combination of plant extracts and plant-derived compounds with the currently used cancer drugs has shown a marked improvement of the conventional drugs' efficacy and reduced toxicity. This study evaluated; phytochemical screening, antiproliferative activity and drug interaction potentials of Moringa oleifera and Indigofera arrecta leaf extracts with 5-fluoro uracil against selected cancer cell lines. Phytochemical screening was done using standard procedures. The common 3– (4, 5-dimethylthiazol-2-yr) -2, 5-diphenyltetrazolium (MTT) assay was used to determine the growth inhibitory potential of the extracts towards cancer cells. Drug interaction assays were done using constant ratio combination method. Alkaloids, terpenoids, tannins, flavonoids, glycosides, phenols and saponins were found to be present in the plant's extracts. M. oleifera and I. arrecta methanol-dichloromethane extracts had the highest activity compared to water extracts. All the extracts showed antiproliferative activities towards; HCC 1395 (breast), DU145 (prostate) and Hela (cervical) cancer cell lines. The extracts were not cytotoxic towards Vero cells (IC50>1000 µg/ml). I. arrecta and M. oleifera inhibited DU145 the most with IC50 values of 111.110 µg/ml and 66.290 µg/ml respectively. The plant extracts synergistically inhibited the growth of cancer cells (CI<1). Combination of the plant extracts and 5-Fluorouracil depicted that the concentration of the conventional drug could be reduced and yet achieve the same desired effect against cancerous cells (Dose reduction index (DRI) >1). Further studies to isolate the bioactive compounds and deduce the probable mechanisms of action are recommended.

Open Access Original Research Article

Attenuation of KCN-induced Neurotoxicity by Solvent Fractions of Antiaris africana Leaf

Rofiat Adewunmi, Omotayo B. Ilesanmi, Olamide O. Crown, Kayode C. Komolafe, Afolabi C. Akinmoladun, Tolulope M. Olaleye, Akintunde A. Akindahunsi

European Journal of Medicinal Plants, Page 1-11
DOI: 10.9734/EJMP/2018/41054

Antiaris africana belongs to the family Moraceae, it is commonly called “False Iroko” tree and one of the medicinal plants used in treatment of mental and nervous disorders in Nigeria. We have previously established the neuroprotective properties of crude extract of A. africana. The present study was thus designed to investigate the neuroprotective effect of different solvent fractions of A. africana against cyanide neurotoxicity in vitro. Cyanide induced a significant (P<0.01) inhibition of NADH succinate dehydrogenase, a key enzyme in mitochondria function as well as significant increase in oxidative stress as observed in the high level of malonedialdehyde (MDA), protein carbonyl (PC) and activity of monoamine oxidase (MAO) and decreased concentration of reduced glutathione (GSH) as compared to the control. Co-administration with different solvent fractions of A. africana (hexane fraction [HFA], dichloromethane fraction [DFA] and methanolic fraction [MFA]) significantly ameliorated the toxic effect of KCN as compared to the induced, untreated group (P<0.05). The results in this study showed that HFA (79.04% reversal of NSD inhibitory activity of KCN), DFA (63.68% and 72.6% activity against KCN induced LPO and PC respectively). However, MFA showed the best activity against GSH depletion caused by KCN (12.21%) and inhibition of MAO activity induced by KCN (94.63%). In conclusion, all the fractions possess neuroprotective activities at varying degrees against mitochondria damage by KCN. This result further substantiated the ethnomedicinal usage of A. africana and can provide novel compounds in the treatment of mitochondria-related neurodegenerative diseases.

Open Access Original Research Article

Antispasmodic and Myorelaxant Activity of Organic Fractions from Origanum majorana L. on Intestinal Smooth Muscle of Rodents

Hanane Makrane, Mohammed Aziz, Hassane Mekhfi, Abderrahim Ziyyat, Mohamed Bnouham, Abdelkhaleq Legssyer, Bernard Gressier, Bruno Eto

European Journal of Medicinal Plants, Page 1-11
DOI: 10.9734/EJMP/2018/41075

Aims: Origanum majorana (Lamiaceae) is a herbaceous and perennial plant that is used in the Moroccan traditional medicine for treating gastrointestinal disorders. The objectives of this study were to confirm the antispasmodic and the myorelaxant activity of organic fractions of Origanum majorana (OM) in rat and rabbit jejunum.

Place and Duration of Study: Laboratory of Physiology, Genetic and Ethnopharmacology, Faculty of Sciences, Mohamed the First University, between September 2013 and July 2014.

Methodology: The antispasmodic and the myorelaxant test evaluated in vitro on rat and rabbit intestines mounted inside an isolated organ system with a temperature of 37ºC, pH 7.4 and continuous oxygenation

Results: The screening study showed those organic fractions of OM decreased the tone of contraction induced by the Carbachol 10-6 M and the KCl 25 mM in the jejunum. The maximum decrease was obtained by dichloromethane fraction of Origanum majorana (DFOM). DFOM induced dose-dependent and reversible inhibition in intestine contraction of rabbit jejunum with IC50 = 0.162 ± 0.002 mg/ml without any alteration of this effect in the presence of adrenergic inhibitors. Pretreatment of the tissue with this fraction (0.01-0.3 mg/ml) induced a dose-dependent shift of the dose-response curve of Carbachol and CaCl2 to the right. The pharmacological inhibitors such as Atropine, L-NAME, Hexamethonium, Nifedipine and Methylene blue did not alter the relaxing effect of DFOM.

Conclusion: The results study confirms the antispasmodic and the myorelaxant effect of OM extract. Also, the results showed that adrenergic receptors, NO, guanylate cyclase or muscarinic receptors pathways did not involve in relaxation induced by DFOM suggesting that it exerts an antispasmodic effect on intestinal smooth muscle like a non-competitive antagonist towards the voltage-dependent calcium channels.

Open Access Original Research Article

Volatile Compounds in the Skin Essential Oil of Moroccan Feijoa sellowiana

M. Elfarnini, A. A. Abdel-hamid, M. Achir, J. Jamaleddine, M. Blaghen

European Journal of Medicinal Plants, Page 1-7
DOI: 10.9734/EJMP/2018/40817

The oil of Feijoa skin (Feijoa sellowiana, family Myrtaceae) was isolated by hydrodistillation in a Clevenger-type apparatus and analyzed by GC-MS analysis. As a result, 76 components were isolated. Among 19 peaks identified which three were reported for the first time in this plant (Elixene, Linalylanthranilate and Farnesol). The sesquiterpene group was predominant, accounting for 97.8% of the total oil. Of which Caryophyllene  was the most abundant 17.7%, followed by Germacrene D14.4%, Humulene 10.5%, Ledene 14%, Spathulenol 8.5%, Cadina-3,9-diene 8.3%, Farnesol 8%, Linalylanthranite 5.6%, β-elemene 4.8%, α-Cubebene 2.7%. Other constituents were also present in oil such as Octanone 5.3%, D limoneme 0.17%, Ocimene 1.6%, Benzoicacidmethylester 1.1%.