Open Access Short Research Article

Antioxidant and Antibacterial Activities of the Essential Oils of Cymbopogon citratus and Citrus sinensis

Charles Ojo Olaiya, Mojisola Esther Ojebode, Kayode Olayele Karigidi

European Journal of Medicinal Plants, Page 1-10
DOI: 10.9734/EJMP/2016/28176

Aims: The use of essential oils from plants as natural antioxidant and antimicrobial is a field of growing interest. The aim of this study was to investigate the antioxidant and antibacterial properties of the essential oils of Cymbopogon citratus L. (lemongrass) and Citrus sinensis (orange peels) independently.

Methodology: Essential oils extracted by hydrodistillation from Cymbopogon citratus and Citrus sinensis were individually assayed for 1,1 –diphenyl- 2 picrylhydrazyl (DPPH) radical scavenging activity, hydrogen peroxide scavenging, reducing power and metal chelating activity in relation to the total phenolic and total flavonoid content of each essential oil. Antimicrobial analyses were carried out using pour plate method for the determination of the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the oils on pathogenic bacteria Staphylococcus epidermidis and Staphylococcus aureus and non-pathogenic bacteria Lactobacillus casei and Lactobacillus brevis.

Results: The two essential oils possessed antioxidant and antibacterial activities. However, the essential oil of C. citratus showed a higher level of total phenolic (372.81±1.36 µg/ml) and total flavonoid (377.88±1.52 µg/ml) content when compared to the essential oil of C. sinensis which showed a lower total phenolic (262.81±2.66 µg/ml) and flavonoid (79.65±1.44 µg/ml) contents. These resulted in a higher level of DPPH radical scavenging and metal chelating activity of                  C. citratus compared to C. sinensis. MIC of 212.5 mg/ml oil concentration was obtained for                  C. citratus against S. epidermidis and less than 106.25 mg/ml against S. aureus while 210 mg/ml oil concentration was obtained for C. sinensis against S. aureus and 850 mg/ml oil concentration against S. epidermidis. MBC was observed for C. citratus at 425 mg/ml while C. sinensis showed MBC at 840 mg/ml oil concentration. None of the oils showed a significant inhibition against the non-pathogenic bacteria compared to the (Gentamycin) negative control.

Conclusion: The essential oils of C. citratus and C. sinensis have potential for use as natural antioxidants and antibacterial agents.

Open Access Original Research Article

Diffusion-ordered Spectroscopy of Flavonol Mixture from Mesembryanthemum forsskaolii (Aizoaceae)

Abeer Moawad, Elham Amin, Rabab Mohammed

European Journal of Medicinal Plants, Page 1-8
DOI: 10.9734/EJMP/2016/27794

Aims: Phytochemical investigation of phenolic content in Mesembryanthemum forsskaolii Hochst. Ex. Boiss (family Aizoaceae).

Methodology: Chromatographic isolation of the total alcohol extract of the herb followed by the spectroscopic identification of the isolated compounds was performed adopting 1D, 2D NMR techniques including Diffusion-Ordered Spectroscopy (DOSY). Quantification of the phenolic content and evaluation of the antioxidant potential of M. forsskaolii was also performed. The total phenolic content (TPC) was determined using the Folin-Ciocalteu method and the total flavonoids content (TFC) was measured via complexation with aluminum chloride and the antioxidant activity was evaluated with DPPH (2.2-diphenyl-1-picrylhydrazyl) assay.

Results: Apigenin (1), kaempferol-3-O-glucoside (2), isorhamnetin-3-O-glucoside (3), apigenin-7-O-glucoside (4) and rutin (5) were isolated and identified. A mixture of isorhamnetin-3-O-rutinoside (6) and kaempferol-3-O-rutinoside (7) was obtained and its composition was identified without the need for further separation. 2D-DOSY experiment was performed, however very poor separation of peaks was obtained, and that may be attributable to close molecular weights of the mixture components and their structure similarity. It is noteworthy that, all the isolated compounds are reported for the first time from this plant. The TPC was 0.090±0.001 gallic acid equivalents in mg/g plant material. The TFC was 0.033±0.006 rutin equivalent in mg/ g plant material. The plant exhibited a very low antioxidant property as DPPH scavenging activity was 0.085±0.002 mg ascorbic acid equivalent antioxidant capacity in 1 g plant material.

Conclusion: Results provide a new addition to the chemical literature of M. forsskaolii, in addition it increases the importance of NMR techniques in flavonoids structure elucidation.

Open Access Original Research Article

Competitive Biodiversity of Human and Vascular Plant Species: The Implications for Pharmaceutical Industries, Health and World Economy Part- 2

Saganuwan Alhaji Saganuwan

European Journal of Medicinal Plants, Page 1-29
DOI: 10.9734/EJMP/2016/27325

Aims: The world population is increasing at alarming rate vis-à-vis the need for health and many vascular medicinal plants are being destroyed. So we risk upsetting the ecological balance of the earth.

Methodology: To avoid ecological health disaster, literature survey of human, vascular plants and vascular medicinal plants populations was carried out with a view to determining their relationship with health and economic development.

Results: A total of 210 countries and Islands with human population (7,423,552,000), area (133,484,423.4 km2) and population density (55.61 per km2) were recorded. The survey of vascular plant species revealed 1,855,563 higher plants, 157,346 medicinal plants and 154,308 endemic plants in 115 countries respectively. Columbia has the highest number of plant species (50,000) in the world. Whereas China has the highest number of human (1,339,190,000) and discovered medicinal plants (11,146). Asteraceae has the largest number of vascular plant species (25,000).

Conclusion: The estimated higher number of vascular plant species, medicinal plants and endemic plants may be due to further discovery, synonym in their names, similarity in their morphology and repeated countings. The increased world population and over exploitation of medicinal plants may pose risk of rarity, extinct, and endanger to some plants with high therapeutic potentials.

Open Access Original Research Article

Phytochemical Screening of Crude Extracts of Bridelia micrantha

C. Mburu, P. G. Kareru, C. Kipyegon, E. S. Madivoli, E. G. Maina, P. K. Kairigo, P. K. Kimani, D. M. Marikah

European Journal of Medicinal Plants, Page 1-7
DOI: 10.9734/EJMP/2016/26649

In Kenya, 22 million people are at risk of malaria, 70% of them are in rural areas, and most of these people use traditional plant-based medicines to treat malaria. The use of natural product-derived drugs and drugs from other sources in combating malaria has however been faced with several challenges, including the emergence of drug resistance parasites, thereby making many of the first line drugs such as chloroquine (CQ) not efficient. The aim of this study was to determine the phytochemical properties of Bridelia micrantha used to treat malaria among the Digo community in Kenya. The crude extracts were obtained using hexane, ethyl acetate, and methanol. A Shimadzu 8400 FT-IR was used to determine the functional groups present in the crude extracts. From the results obtained, various functional groups characteristic of phenolics, tannins, saponins, alkaloids, flavonoids, and glycosides were found to be present. A quantitative assay was performed using Shimadzu 6200 UV-VIS spectrophotometer. The total phenolics and flavonoids were found to be highest in barks with a concentration of 0.84±0.14 mg/g and of 0.86±0.03 mg/g respectively while Saponin content was found to be highest in leaves with a concentration of 12.66±0.23 mg/g. Alkaloid content, on the other hand, was found to be highest in roots with a concentration of 313.44±0.05 mg/g.

Open Access Original Research Article

In vitro Antileishmanial Activity of Extracts from Endemic Moroccan Medicinal Plant Salvia verbenaca (L.) Briq. ssp verbenaca Maire (S. clandestina Batt. non L)

Abdeslam Et-Touys, Hajiba Fellah, Faiza Sebti, Meryem Mniouil, M’hammed Aneb, Houria Elboury, Ahmed Talbaoui, Nadia Dakka, Abderrahim Sadak, Youssef Bakri

European Journal of Medicinal Plants, Page 1-8
DOI: 10.9734/EJMP/2016/27891

Aims: The aim of this study was to evaluate in vitro the antileishmanial activities of organic extracts (methanol, n-hexane and dichloromethane extract) from Salvia clandestina (Lamiaceae) used in Moroccan medicinal plant.

Study Design: Evaluation of in vitro antileishmanial activity of extracts and determination phenolic contents.

Place and Duration of Study: After plant collection from the region of Rabat-Morocco, further work was carried out in Parasitology Laboratory of the National Institute of health and Laboratory of Biochemistry-Immunology, Faculty of Science, Mohammed V University of Rabat, Morocco from February 2015 to march 2016.

Methodology: The plant was extracted using organic solvents and using Soxhlet. The antileishmanial activity of extracts was tested against three leishmanial strains, Leishmania major, Leishmania tropica and Leishmania infantum in their promatigotes form, using MTT assay. The total phenolic content was assessed by the Folin-Ciocalteau assay and total flavonoid content was assessed by aluminium chloride (AlCl3) colorimetric assay.

Results: The MTT based colorimetric assay showed reduced promastigotes viability on the all strains tested. The best growth inhibition was observed with n-hexane and dichloromethane extracts of Salvia clandestina (IC50≤ 155.43 µg/ml) compared to N-methyl glucamine antimoniate (Glucantime®) (IC50>1000µg/ml) used as control, after 72 h of treatment. Phenolic content of S. clandestina extracts ranged between 107.52±3.12 and 74.41±4.96 mg GAE/g extract, and the flavonoid content ranged between 24.64±3.65 and 16.31±3.69 mg QE/g extract.

Conclusion: The current investigation reveals that S. clandestina extracts possess activity against three Leishmania species. S. clandestina need further investigation so that the pure bioactive antileishmanial compounds should be isolated with cost effective, promising results and less side effects.

Open Access Review Article

Competitive Biodiversity of Human and Vascular Plant Species: The Implications for Pharmaceutical Industries, Health and World Economy Part- 1

Saganuwan Alhaji Saganuwan

European Journal of Medicinal Plants, Page 1-12
DOI: 10.9734/EJMP/2016/26233

Aims: This work is a survey of the distribution of vascular plant species that have medicinal values.

Methodology: The census, medicinal uses, economic benefits and existence threats of the plants were reassessed.

Results: Additional members of Asteraceae have been discovered from 12,000 to 20,000 species with Centaurea species (500) mostly used in the family. Stevia produces steviol glycoside that is 200–300 sweeter than sugar with market value of 2-3 billion yen/year. Species of Orchidaceae (20,000) have been discovered with 3,000 and 2,500 endemic to Columbia and Ecuador respectively. Other members of family that have been increasingly discovered are Fabaceae (8,000), Euphorbiaceae (7,300) with Euphorbia species (1,600), Rosaceae (3,000), Boraginaceae (2,000), Polygonaceae (1,200) whereas Acacia (1,380) and Salvia (900) species have also been discovered.

Conclusion: The increased number of species may be due to additional discovery, genetic polymorphism and evolution. However, threats to their existence may be due to urbanization, deforestation, over exploitation, environmental pollution and fires. Therefore, management strategies aimed at conserving medicinal plants biodiversity are very important for development of raw materials for pharmaceutical industries and synthesis of drugs for treatment of human and animal diseases that can contribute to world economy. Despite more plants with medicinal values have been discovered their over use could threaten their existence. Hence, North America, Argentina, China and Australia have started embarking on genetic propagation of their threatened plants.