Analgesic and Anti-Inflammatory Effect of Ghanaian Medicinal Plants

Medicinal plants continue to be used in various cultures of the world as safe therapeutic agents against various issues including pain and inflammation which underlie almost every disease process. In Ghanaian traditional medicine, various parts of several plants have been used alone or in combination of therapies for the treatment of various painful inflammatory conditions. In this chapter, the anti-inflammatory and analgesic (antinociceptive) properties of selected medicinal plants from Ghana are reviewed. Evidence of pharmacological activities of crude extracts and fractions in in-vitro and in-vivo models, bioactive anti-inflammatory and antinociceptive compounds isolated as well as possible mechanisms of anti-inflammatory and antinociceptive action are discussed

Authentication and quality control of Uapaca heudelotii Baill. - An investigation of pharmacognostic, phytochemical and physicochemical properties of its leaves and stem bark

Uapaca heudelotii Baill. is well known in various African cultures for its application in the treatment of infections and inflammatory conditions. This study was focused on providing standard identification parameters for authentication and quality assurance of U. heudelotii through morphological observations, screening of phytochemical constituents, fluorescence, spectroscopic and physicochemical analysis. U. heudelotii leaves are simple, elliptic and arranged in whorls. The bark is greyish-brown with longitudinal striations on the outer surface and pale red on the inner surface. Leaf lamina microscopy displayed anticlinal polygonal straight-walled epidermal cells, with anisocytic stomata found only on the abaxial surface. Leaf surface constants were determined. Microscopy of powdered leaves and barks revealed the presence of epidermal cells, starch grains, calcium oxalate, sclereids and pitted vessels. Alkaloids, flavonoids, coumarins, saponins, triterpenoids, phytosterols and tannins were identified in both stem bark and leaves. The total phenolic content for the leaf and bark were 219.2 ± 10.013 and 153.9 ± 1.602 mg/g gallic acid equivalent respectively. The total ?avonoid contents were recorded as 1036 ± 33.37 and 310.2 ± 79.00 mg/g quercetin equivalent for the leaf and bark respectively. The total ash for the leaf and bark was 6.41 ± 0.208 and 5.01 ±0.258 respectively. The pH values for the aqueous and alcoholic extracts were slightly acidic (3-5). In elemental analysis, lead (Pb) was detected within the acceptable limit (0.0019-0.0025 mg/kg). In conclusion, the current results have provided standard parameters for the correct identification and quality assessment of U. heudelotii

Macaranga barteri stem bark extract exerts anti-inflammatory and anti-hyperalgesia activity in murine models

This study was undertaken to evaluate the anti-inflammatory, anti-hyperalgesia and antioxidant activity of the hydro-alcoholic stem bark extract of Macaranga barteri (MBE). The carrageenan-induced foot oedema and Hargreaves thermal hyperalgesia models in rats were used to examine the anti-inflammatory and anti-hyperalgesic effects respectively. The 2, 2-diphenyl-2-picrylhydrazyl hydrate (DPPH) free radical scavenging and total antioxidant capacity assays were used to determine the antioxidant activity. In a curative protocol, MBE (30, 100, 300 mg kg-1, p.o.) dose dependently and significantly inhibited carrageenan-induced foot oedema by 37.01 ± 13.08, 53.01 ± 9.87 and 64.11 ± 9.05% respectively (ED50 = 89.37 ± 7.52 mg kg-1). The extract further attenuated cutaneous hyperalgesia by prolonging paw withdrawal latencies towards an external heat stimulus with an ED50 of 105.5 ± 4.22 mg kg-1. MBE was found to possess a total antioxidant capacity of 531.62 ± 10.98 mg g-1 dry weight (Gallic acid equivalent) and scavenged DPPH free radicals with an IC50 of 19.45 ± 1.46 µg/mL. The results provide the first report on the anti-inflammatory, analgesic and antioxidant activity of M. barteri stem bark and partly justify its traditional use in the management of inflammation and pain. This could be attributed to phytochemicals such as tannins, terpenoids, sterols, coumarins and flavonoids which were identified in preliminary phytochemical studies of the stem bark

In-vitro Anti-cercarial activity of extracts and steroidal alkaloids from the stem bark of Holarrhena floribunda (G. Don) Dur. & Schinz

Context: Schistosomiasis continues to be the leading cause of morbidity and mortality among the neglected tropical diseases. Apart from the high cost of chemotherapy, concerns over drug resistance and tolerance have been raised in the past decade. Objective: The aim of the study was to evaluate the anticercarial activity of extracts and compounds from the stem bark of Holarrhena floribunda on cercaria of Schistosoma haematobium. Methods: Hydroethanolic and alkaloidal extracts from the stem bark of H. floribunda were tested on cercaria at concentrations between 500.00 and 15.625 μg/mL for 180 minutes and assessing the percentage viability at time intervals of 0, 15, 30, 60, 120 and 180 minutes. Praziquantel, used as reference drug, and the isolated compounds were tested at similar concentrations. The cercaria mortalities and IC50 of extracts and compounds were estimated after 30 minutes of incubation. Results: The 70 %v/v ethanol extract showed the highest activity (IC50=20.09±1.11 μg/mL) with praziquantel giving IC50 of 695.50±1.12. The alkaloids holonamine, holadienine and conessine, isolated from the stem bark, showed considerable cercaricidal activity with the latter recording an IC50 of 33.28±1.04. Conclusion: The study gives first-hand knowledge of the anti-cercarial activity of H. floribunda and its steroidal alkaloids. This gives credence to the traditional uses of the plant as an anti-parasitic agent

Corrigendum: The Ghanaian Flora as a Potential Source of Anthelmintic and Anti-Schistosomal Agents

Parasitic infections including schistosomiasis and soil transmitted helminthiasis are the most commonly encountered Neglected Tropical Diseases (NTDs) in the world. These diseases remain a major public health concern affecting millions of people especially those living in poor regions where access to effective conventional health care is a challenge. Interventions to control these infections in endemic areas have not been successful due to the high cost of drugs, limited availability as well as inequity of access to preventive chemotherapies. Another problem is the development resistance to the limited number of recommended medications due to their intensive use in both human and live-stock. There is an increasing awareness of the potential of natural products as chemotherapeutic agents to combat parasitic infections. Natural products may offer an unlimited source of chemically diverse drug molecules which may be safe, efficient, less toxic, less expensive and readily available for use especially in low-income countries. The Ghanaian flora provides such a ready source for new therapeutic interventions for the local population. Several researches have provided evidence of the anti-parasitic activity of Ghanaian medicinal plants. This chapter provides a review with special focus on medicinal plants collected from Ghana with anthelmintic and anti-schistosomal activity. Evidence of pharmacological activities of crude extracts, fractions and bioactive phytoconstituents as well as possible mechanisms of action where investigated are discussed

Indigenous Medicinal Plants as Biofilm Inhibitors for the Mitigation of Antimicrobial Resistance

The majority of indigenes in the rural areas of Ghana use herbal medicines for their primary health care. In this study, an ethnobotanical survey was undertaken to document medicinal plants used by traditional healers in the Ejisu-Juaben district in the Ashanti region of Ghana to treat infections and to further investigate the antibiofilm formation properties of selected plants in resisting pathogenic bacteria. Seventy medicinal plants used by traditional practitioners for the treatment of skin infections and wounds were documented from the ethnobotanical survey. Forty out of the seventy plants were collected and their methanol extracts evaluated for antimicrobial activity by the agar diffusion assay. Extracts that showed antibacterial activity were tested for biofilm inhibitory activity, and the most active plant was subsequently purified to obtain the active constituents. Biofilm formation was significantly mitigated by petroleum ether, ethyl acetate, and methanol extracts of Holarrhena floribunda stem bark. Bioassay-guided fractionation of an alkaloidal extract prepared from the methanol fraction led to the isolation of three steroidal alkaloids, namely, holonamine, holadienine, and conessine. The isolated compounds demonstrated varying degrees of biofilm formation inhibitory properties. The current study reveals that screening of indigenous medicinal plants could unravel potential leads to salvage the declining efficacy of conventional antibiotics. Holarrhena floribunda stem bark extract has strong biofilm formation inhibition properties, which could be attributed to the presence of steroidal alkaloids

In Vivo Antiplasmodial Activity of Different Solvent Extracts of Myrianthus libericus Stem Bark and Its Constituents in Plasmodium berghei-Infected Mice

The emergence and resurgence of P. falciparum resistance to generations of antimalarial drugs have prompted the search for new, effective, and safe antimalarial agents. This study aimed at investigating the in vivo antiplasmodial activity of the 70% hydroethanolic extract and constituents of the stem bark of Myrianthus libericus based on its ethnomedicinal use as an antimalarial agent. The antiplasmodial activity was assessed in Swiss albino mice employing the 4-day suppressive and Rane’s tests. MLB significantly (p<0.0001) suppressed parasitaemia by 52.26%, 65.40%, and 77.11% at 50, 100, and 200 mg·kg−1 doses, respectively, in the 4-day suppressive test. In Rane’s test, the highest parasitaemia suppression of 72.50% was recorded at a dose of 200 mg·kg−1 of the extract. Fractionation of the bioactive ethyl acetate fraction by solvent-solvent partitioning and column chromatography led to the isolation of friedelan-3-one and stigmasterol being reported for the first time from this species. The compounds demonstrated remarkable antiplasmodial activity by suppressing parasitaemia by 65–72% in the suppressive test and 61–70% in the curative test at doses of 10–30 mg·kg−1. Both the extract and the isolated compounds significantly prolonged the survival time of infected mice and averted the cardinal signs associated with P. berghei-induced malaria including weight loss, hypothermia, and haemolysis. The results obtained confirm the prospect of M. libericus as an important source of new antimalarial compounds and justifies its folkloric use as an antimalarial agent

Ethnobotanical Survey and Cercaricidal Activity Screening of Medicinal Plants Used for Schistosomiasis Treatment in Atwima-Nwabiagya District, Ashanti Region, Ghana

This study focused on documenting and evaluating the cercaricidal activity of medicinal plants used for schistosomiasis treatment in an endemic area in Ghana. Through semistructured questionnaires, personal interviews with herbalists in communities surrounding the Barekese dam in the Atwima-Nwabiagya district, where the disease is endemic, were carried out. Thirty medicinal plants distributed in 19 families were reported to be used for schistosomiasis treatment in the survey. Information on the plants, including scientific names, common names, families, and the used plant part were recorded. The families Apocynaceae and Euphorbiaceae recorded the highest number of plants (14% each), followed by Asteraceae (10%), Loranthaceae (7%), and Rubiaceae (7%). In vitro cercaricidal activity of methanol extracts of nine out of the thirty plants was performed by exposing human Schistosoma mansoni cercariae obtained from Biomphalaria pfeifferi to various concentrations of extracts over a duration of 240 minutes. All the plants tested demonstrated time- and concentration-dependent cercaricidal activity. With lethality being set at  Balanites aegyptiaca (LC50 = 7.1) > Xylia evansii (LC50 = 11.14) > Jathropha multifida (LC50 = 12.9) > Justicia flava (LC50 = 22.9) > Anopyxis klaineana (LC50 = 182.81) > Ximenia americana (LC50 = 194.98) > Loranthus lecardii (LC50 = 223.87) > Bridelia tenufolia (LC50 = 309.03) > Zanthoxylium zanthoxyloides (LC50 = 851.94). Phytochemicals, including alkaloids, tannins, triterpenes, saponins, phytosterols, and flavonoids were identified in the plants. The result of this study gives scientific credence to the traditional use of these plants in the treatment of schistosomiasis and proves that the rich botanical knowledge of medicinal plants provides an incredible starting point for the discovery of new anti-schistosomal drugs for the local population