Browsing by Author "Orman, E."
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Item Anthelmintic Agents from African Medicinal Plants: Review and Prospects(Evidence-Based Complementary and Alternative Medicine, 2022) Jato, J.; Orman, E.; Boakye, Y.D.; Bekoe, E.O.; Bekoe, S.O.; Asare-Nkansah, S.; Spiegler, V.; Hensel, A.; Liebau, E.; Agyare, C.Soil-transmitted helminthiasis affects more than 1.5 billion people globally and largely remains a sanitary problem in Africa. These infections place a huge economic burden on poor countries and affect livestock production, causing substantial economic losses and poor animal health. The emergence of anthelmintic resistance, especially in livestock, and the potential for its widespread in humans create a need for the development of alternative therapies. Medicinal plants play a significant role in the management of parasitic diseases in humans and livestock, especially in Africa. This report reviews anthelmintic studies that have been conducted on medicinal plants growing in Africa and published within the past two decades. A search was made in various electronic databases, and only full articles in English were included in the review. Reports show that aqueous and hydroalcoholic extracts and polar fractions obtained from these crude extracts form the predominant (80%) form of the extracts studied. Medicinal plants, extracts, and compounds with different chemical groups have been studied for their anthelmintic potential. Polyphenols and terpenoids are the most reported groups. More than 64% of the studies employed in vitro assays against parasitic and nonparasitic nematode models. Egg hatch inhibition, larval migration inhibition, and paralysis are the common parameters assessed in vitro. About 72% of in vivo models involved small ruminants, 15% rodents, and 5% chicken. Egg and worm burden are the main factors assessed in vivo. There were no reports on interventions in humans cited within the period under consideration. Also, few reports have investigated the potential of combining plant extracts with common anthelmintic drugs. This review reveals the huge potential of African medicinal plants as sources of anthelmintic agents and the dire need for in-depth clinical studies of extracts, fractions, and compounds from African plants as anthelmintic agents in livestock, companion animals, and humans.Item Development and Validation of an Ion-Pair HPLC-UV Method for the Quantitation of Quinoline and Indoloquinoline Alkaloids in Herbal and Pharmaceutical Antimalarial Formulations(Hindawi Journal of Chemistry, 2022) Bekoe, S.O.; Orman, E.; Adjabui, S.A.; Brobbey, A.A.; Oppong-Kyekyeku, J.; Opuni, K.F-M.; Kuntworbe, N.; Asare-Nkansah, S.Quinine- and cryptolepine-based antimalarials serve as valuable alternatives to artemisinin-based combination therapies (ACTs) in Ghana. *eir use, however, is associated with adulteration and substandard quality challenges. An HPLC method targeting quinoline and indoloquinoline antimalarial alkaloids was developed, validated, and applied to evaluate herbal and pharmaceutical antimalarial formulations (HPAFs) and starting materials (APIs). *e separation/quantitation of the alkaloids (including quinine, quinidine, cinchonine, cinchonidine, dihydroquinine, dihydroquinidine, and cryptolepine) was achieved on a Zorbax SB-CN column (250mm× 4.6 mm, 5 μm), with an isocratic elution system of methanol: trifluoroacetic acid (0.1%, v/v) (15 : 85, v/v) at 1.5 mL/min and 223 nm. Method validation was according to ICH Q2(R1) guidelines. It was then used to assess the quality of APIs (n = 3) and HPAFs (n = 44) including quinine-based pharmaceutical antimalarial formulations (QBPAFs) (n = 23) and herbal antimalarial products (HAMPs). *e method was found to be specific, selective, accurate, precise, and robust toward the alkaloids with linearity achieved within specified concentration ranges (r2 > 0.995 for all analytes). Analyte stability ranged between 6 and 12 hours. All the APIs contained quinine <99.0%–101.0%, with dihydroquinine and cinchonidine at levels compliant with the established acceptance criteria. *e QBPAFs had quinine content ranging between 50.2% and 151.2%, with 43.5% (n = 10/23) of them complying with the acceptance criteria. *erelated alkaloids observed in the QBPAFs included quinidine (56.5%, n = 13/23), dihydroquinine (100%, n = 23/23), dihydroquinidine (21.7%, n = 5/23), cinchonine (17.4%, n = 4/23), and cinchonidine (95.7%, n = 22/23). For the HAMPs, 81.0% (n = 17/21) were adulterated with quinine (0.59 ± 0.04 mg/10 mL–86.03 ± 0.02 mg/10 mL). Cryptolepine was identified in 19% (n = 4/21) of the HAMPs with concentration ranging between 43.99 ± 0.43 μg/mL and 747.86 ± 0.34 μg/mL. In conclusion, the application of the ion-pair HPLC method targeting quinoline and indoloquinoline antimalarials has demonstrated the presence of quality and poor-quality HPAFs on the Ghanaian market.Item Metabolite profiling, antifungal, biofilm formation prevention and disruption of mature biofilm activities of Erythrina senegalensis stem bark extract against Candida albicans and Candida glabrata(PLOS ONE, 2022) Harley, B.K.; Quagraine, A.M.; Neglo, D.; Aggrey, M.O.; Orman, E.; Mireku-Gyimah, N.A.; Amengor, C.D.; Jato, J.; Saaka, Y.; Fleischer, T.C.The antifungal activity of the 70% ethanol stem bark extract of Erythrina senegalensis (ESB) against different strains and drug resistant clinical isolates of Candida albicans and Candida glabrata were evaluated in the study. The effect of ESB on biofilms as well as its activity in combination with fluconazole, nystatin or caspofungin against the Candida strains were also evaluated. We then evaluated the antifungal activity of a microemulsion formulation of ESB against planktonic and biofilms of the Candida species. UPLC-QTOF-MS2 analysis was then undertaken to identify the phytoconstituents of the extract and UPLC fingerprints developed for the routine authentication as part of quality control measures. ESB exerted strong antifungal activities against C. albicans ATCC 10231 and SC5314 strains, and C. glabrata ATCC 2001 strain with minimum inhibitory concentration (MIC) values from 3.91 to 31.25 μg/mL and minimum fungicidal concentrations (MFCs) that ranged from 62.5 to 250 μg/mL. It also exhibited potent antifungal activities (MIC = 4–64 μg/mL) against a collection of C. albicans and C. glabrata clinical isolates that were resistant to either nystatin or azole antifungals. The formulated ESB demonstrated higher antifungal potency against the C. albicans and C. glabrata strains with MIC values of 3.91–31.25 μg/mL which was the same as the MFC values. The extract and its microemulsion formulation were active against biofilms of the strains of the Candida species inhibiting their biofilm formations (SMIC50 = 16–64 μg/mL) and their preformed biofilms (SMIC50 = 128 –>512 μg/mL). ESB also exhibited synergistic antifungal action with fluconazole and nystatin against C. albicans ATCC 10231 and C. glabrata ATCC 2001 strains in the checkerboard assay. Chemical characterization of the extract revealed the presence of phenolic compounds such as flavonoids and their prenylated derivatives, anthracene glycosides and alkaloids. UPLC Fingerprints of the extract was also developed and validated for routine identification and authentication of the stem bark of E. senegalensis. The study findings have demonstrated that the stem bark of E. senegalensis is as a potential source of bioactive compounds that could be developed as novel antifungal agents.Item Phytochemical Analysis and Elemental Contents of Varieties of Polyalthia longifolia (Sonn.) Thwaites(Journal of Natural Remedies, 2024) Bekoe, E. O.; Lartey, M.; Orman, E.; et alPolyalthia longifolia (Sonn.) is a medicinal plant that belongs to the family Annonaceae, and it is distributed in the tropics. This plant is widely grown in West Africa for its ornamental and medicinal purposes. There are two varieties of P. longifolia which are commonly distinguishable by the direction of their branches. One has spreading perpendicular branches, and the other has drooping pendulous branches. Traditional herbal practitioners believe that one variety (P. longifolia cv. pendula) is more medicinal than the other. This study, therefore, sought to investigate the phytochemical components of the two varieties of P. longifolia by HPTLC, UPLC, and elemental analysis by ICP-EOS. No observable differences were found in the phytochemical and elemental profiles of these varieties that could help distinguish one from the other or could account for its supposed differences in medicinal properties. A total of 22 elements were detected in the samples of the two varieties of the plant. Qualitatively, the elemental content of both varieties was similar. Only Iridium was not detected in all samples. Heavy metals including As, Pb, Cd, and Hg had their levels above the recommended limits.Item Reservoir of Antibiotic Residues and Resistant Coagulase Negative Staphylococci in a Healthy Population in the Greater Accra Region, Ghana(MDPI, 2022) Bekoe, S.O.; Hane-Weijman, S.; Trads, S.L.; Orman, E.; Opintan, J.; Hansen, M.; Frimodt-Møller, N.; Styrishave, B.Antimicrobial resistance threatens infectious disease management outcomes, especially in developing countries. In this study, the occurrence of resistant coagulase-negative staphylococci (rCoNS) and antibiotic residues in urine samples of 401 healthy individuals from Korle-Gonno (KG) and Dodowa (DDW) in Ghana was investigated. MALDI-ToF/MS with gram-staining techniques detected and identified the CoNS. SPE-LC-MS/MS detected and quantified nine commonly used antibiotics in the samples. The results showed 63 CoNS isolates detected in 47 (12%) samples, with S. haemolyticus (78%) and S. epidermidis (8%) being predominant. Most of the isolates (95%) were resistant to at least one antibiotic, with the highest resistance observed against sulphamethoxazole (87%). Resistance profiles in samples from DDW and KG were largely comparable, but with some differences. For instance, DDW isolates were more resistant to gentamicin (p = 0.0244), trimethoprim (p = 0.0045), and cefoxitin (p = 0.0078), whereas KG isolates were more resistant to erythromycin (p = 0.0356). Although the volunteers had not knowingly consumed antibiotics two weeks before sampling, antibiotic residues, ranging between 1.44–17000 ng mL−1 were identified in 22% of urine samples. Samples with antibiotic residues were likely to also contain rCoNS (89%). The most frequent antibiotics detected were tetracycline (63%) and ciprofloxacin (54%). Healthy individuals could thus be reservoirs of antibiotic residues and rCoNS at the community level.Item Towards the development of analytical monograph specifications for the quality assessment of the medicinal plant Phyllanthus urinaria(Phytochemistry, 2023) Orman, E.; Bekoe, S.O.; Bekoe, E.O.; et al.Many people in developing countries rely on herbal remedies for their primary healthcare needs. The challenge however is that several of these products lack proper documentation of quality and safety. To ensure consistent quality, validated methods are needed to establish and control quality attributes associated with identity, purity, and levels of bioactive constituents of the respective herbal materials. The present study focused on Phyllanthus urinaria (PU), a widely used medicinal plant in Ghana and West Africa that lacks the necessary quality control standards. The study aimed to develop an HPTLC identification method, which together with UPLC-ESI-Q-TOF MS/MS analysis established the identity of PU samples and differentiated PU from other closely related Phyl lanthus species. Quantitative UPLC and HPTLC methods were developed to assess the contents of selected active markers in the PU samples, which invariably led to the proposal of acceptance criteria for the active markers. Prior to the content analyses, the sample extraction procedure was optimized through the use of Design of Experiment method. The effects of harvest time and geographic origin on the content of active compounds were demonstrated in the investigations. PU samples were also found to be contaminated with higher levels of pes ticides like chlorpyrifos and folpet. Essentially, this study provides analytical protocols, insights into the quality status of PU samples in Ghana, and analytical specifications contained in a drafted monograph for future consideration in regional and subregional African pharmacopoeias.