Medicinal plants used as excipients in the history in Ghanaian herbal medicine

Antimicrobial activity of Xylopia pancheri Baill. Leaf extract against susceptible and resistant Staphylococcus aureus

Antibacterial activity of Xylopia pancheri Baill. (Annonaceae) leaf extract was investigated against susceptible Staphylococcus aureus, methicillin-resistant S. aureus (MRSA) and extended-spectrum-β-lactamase (ESBL)-producing Pseudomonas aeruginosa. Results showed that X. pancheri leaf extract displayed antibacterial activity against S. aureus with higher inhibitory effect on MRSA compared to control gentamycin antibiotic, and IC₅₀ value of 36.97 μg/mL [95%CI:29.59-46.18] against MRSA.

The use of black pepper (Piper guineense) as an ecofriendly antimicrobial agent to fight foodborne microorganisms

Consumers demand clean-label food products, necessitating the search for new, natural antimicrobials to meet this demand while ensuring food safety. This review aimed at investigating the antimicrobial properties of black pepper (Piper guineense) against foodborne microorganisms. The existence of foodborne illness, food spoilage, food waste, the resulting negative economic impact of these issues, and consumer interests have all pushed the food industry to find alternative, safe, and natural antimicrobials to be used in foods and beverages. Consumers have also influenced the demand for novel antimicrobials due to the perceived association of current synthetic preservatives with diseases and adverse effects on children. They also have a desire for clean-label products. These combined concerns have prompted researchers at investigating plant extracts as potential sources for antimicrobials. Plants possess many antimicrobial properties; therefore, evaluating these plant extracts as a natural source of antimicrobials can lead to a preventative control method in reducing foodborne illness and food spoilage, inclusively meeting consumer needs. In most regions, P. guineense is commonly utilized due to its potent and effective medicinal properties against foodborne microorganisms.

An ethnobotanical survey and antifungal activity of Piper guineense used for the treatment of fungal infections in West-African traditional medicine

ETHNOBOTANICAL RELEVANCE

Piper guineense occurs commonly in West Africa where it is used for fungal infections instead of the costly and not always accessible conventional antifungals. Fungal, yeast-based diseases are common in West-Africa especially among those living with HIV/AIDS, and thus this study was performed in Imo state, South-Eastern Nigeria, where P. guineense is predominantly used for the treatment of fungal diseases, such as skin rashes, oral thrush and vaginosis.

AIM OF STUDY

The scarce number of previous studies on the documentation of the traditional uses of P. guineense extracts for the treatment of fungal infections in Nigeria prompted this survey. The investigation focused on how traditional healers recognize and diagnose fungal infections, how P. guineense is collected, on the various parts used for the treatments, methods of preparations, administrations and treatments. In addition, an in vitro antifungal screening of P. guineense fruit and leaf extracts of various polarities, and piperine and piperlongumine, representing the main constituents in these extracts, were performed.

METHODS

A house to house ethnobotanical survey was conducted using questionnaires. Twenty traditional medical practitioners (TMP) and herb sellers from ten villages were interviewed. Four human pathogenic strains of yeast and Cryptococcus neoformans, a yeast-like basidiomycete causing meningitis in immunocompromised individuals, were used for the antifungal screening.

RESULTS

The traditional medical practitioners (TMP) and herb sellers explained that the leaves and fruits are the most commonly used plant parts for the treatments. The oral intake of the extracts in locally produced bamboo alcohol (Kai-kai) is the most common method of administration. In accordance with these recorded traditional uses, we found that extracts of P. guineense were growth inhibitory against the fungal strains with MIC values ranging from 39 to 2500 µg/mL. The lowest MIC value of 39 µg/mL was recorded for a methanol fruit extract against Candida albicans, C. glabrata and C. tropicalis. In addition, ethanol and hexane fruit extracts were effective against the growth of C. albicans and C. glabrata, respectively, with a MIC of 78 µg/mL. Piperlongumine and piperine were active against C. albicans with MIC values of 39 and 78 µg/mL respectively.

CONCLUSION

P. guineense fruit and leaf extracts, as well as their piperamide alkaloid constituents piperine and piperlongumine, have interesting antifungal properties and could have potential as new antifungal scaffolds. Our results warrant further in-depth investigations to isolate and characterize piperamide alkaloids and other compounds responsible for the antifungal activity in the extracts.

Alkaloid-Rich Crude Extracts, Fractions and Piperamide Alkaloids of Piper guineense Possess Promising Antibacterial Effects

Piper guineense is a food and medicinal plant commonly used to treat infectious diseases in West-African traditional medicine. In a bid to identify new antibacterial compounds due to bacterial resistance to antibiotics, twelve extracts of P. guineense fruits and leaves, obtained by sequential extraction, as well as the piperine and piperlongumine commercial compounds were evaluated for antibacterial activity against human pathogenic bacteria. HPLC-DAD and UHPLC/Q-TOF MS analysis were conducted to characterize and identify the compounds present in the extracts with promising antibacterial activity. The extracts, with the exception of the hot water decoctions and macerations, contained piperamide alkaloids as their main constituents. Piperine, dihydropiperine, piperylin, dihydropiperylin or piperlonguminine, dihydropiperlonguminine, wisanine, dihydrowisanine and derivatives of piperine and piperidine were identified in a hexane extract of the leaf. In addition, some new piperamide alkaloids were identified, such as a piperine and a piperidine alkaloid derivative and two unknown piperamide alkaloids. To the best of our knowledge, there are no piperamides reported in the literature with similar UVλ absorption maxima and masses. A piperamide alkaloid-rich hexane leaf extract recorded the lowest MIC of 19 µg/mL against Sarcina sp. and gave promising growth inhibitory effects against S. aureus and E. aerogenes as well, inhibiting the growth of both bacteria with a MIC of 78 µg/mL. Moreover, this is the first report of the antibacterial activity of P. guineense extracts against Sarcina sp. and E. aerogenes. Marked growth inhibition was also obtained for chloroform extracts of the leaves and fruits against P. aeruginosa with a MIC value of 78 µg/mL. Piperine and piperlongumine were active against E. aerogenes, S. aureus, E. coli, S. enterica, P. mirabilis and B. cereus with MIC values ranging from 39–1250 µg/mL. Notably, the water extracts, which were almost devoid of piperamide alkaloids, were not active against the bacterial strains. Our results demonstrate that P. guineense contains antibacterial alkaloids that could be relevant for the discovery of new natural antibiotics.

Optimization of Thin-layer Chromatography and High-Performance Liquid Chromatographic Method for Piper guineense Extracts

In this study, a thin-layer chromatography (TLC) and a high performance liquid chromatographic (HPLC) methods were developed for the chemical profiling, qualitative and quantitative analysis of P. guineense extracts. To obtain a chromatogram with satisfactory resolution and favorable retention time, DryLab software was used to simulate and optimize a HPLC method for the analysis of P. guineense extracts. The aim was to achieve the best possible overall resolution while keeping the analysis time and solvent consumption to a minimum. With the optimized method, a total of 16 main components in the extract were separated with favorable resolution. Optimal TLC conditions were also developed using solvents of various solvent strength (ST) and solvent selectivity (PS) values. The mobile phase composition was systematically tested using various proportions of solvents differing in ST and PS values under the same experimental conditions. During the optimization, emphasis was set on achieving the best possible overall separation of the main components of the extracts (for example piperine). In addition, the effects of the developing chamber was tested using three types of unsaturated chamber conditions: horizontal chamber in sandwich configuration, horizontal chamber in non-sandwich configuration and twin-trough vertical chamber. During the study, a TLC method was developed, and the best mobile-phase composition giving favorable resolution of the bands was toluene: ethyl acetate (PS 6-4 corresponding to 60:40 % v/v). The developing chamber conditions did not affect the TLC separation efficacy in the analysis of P. guineense extracts. The HPLC method was applied to determine the percentage content of piperine in P. guineense. The piperine content was 0.43 % w/w, linearity (0.997), interday precision (% relative standard deviation (RSD), 1.6), intraday precision (% RSD, 2.7 – 5.9), recovery (98.4%), limit of detection (0.001 μg /mL) and limit of quantification (0.003 μg /mL).

The effect of inhalation of Citrus sinensis flowers and Mentha spicata leave essential oils on lung function and exercise performance: a quasi-experimental uncontrolled before-and-after study

BACKGROUND

Recently, there has been an increased interest in the effects of essential oils on athletic performances and other physiological effects. This study aimed to assess the effects of Citrus sinensis flower and Mentha spicata leaves essential oils inhalation in two different groups of athlete male students on their exercise performance and lung function.

METHODS

Twenty physical education students volunteered to participate in the study. The subjects were randomly assigned into two groups: Mentha spicata and Citrus sinensis (ten participants each). One group was nebulized by Citrus sinensis flower oil and the other by Mentha spicata leaves oil in a concentration of (0.02 ml/kg of body mass) which was mixed with 2 ml of normal saline for 5 min before a 1500 m running tests. Lung function tests were measured using a spirometer for each student pre and post nebulization giving the same running distance pre and post oils inhalation.

RESULTS

A lung function tests showed an improvement on the lung status for the students after inhaling of the oils. Interestingly, there was a significant increase in Forced Expiratory Volume in the first second and Forced Vital Capacity after inhalation for the both oils. Moreover significant reductions in the means of the running time were observed among these two groups. The normal spirometry results were 50 %, while after inhalation with M. spicata oil the ratio were 60 %.

CONCLUSION

Our findings support the effectiveness of M. spicata and C. sinensis essential oils on the exercise performance and respiratory function parameters. However, our conclusion and generalisability of our results should be interpreted with caution due to small sample size and lack of control groups, randomization or masking. We recommend further investigations to explain the mechanism of actions for these two essential oils on exercise performance and respiratory parameters.

TRIAL REGISTRATION

ISRCTN10133422, Registered: May 3, 2016.

An ethnobotanical study of plants used to treat liver diseases in the Maritime region of Togo

ETHNOPHARMACOLOGICAL RELEVANCE

In Togo, many persons still rely on plants for healing, however very little is known about the medicinal practices of the indigenous people. The present study aimed to document the medicinal plant utilization for the management of liver diseases in the Maritime region of the country.

METHODOLOGY

This was an ethnobotanical survey conducted in the Maritime region of Togo from June to August 2015. The data were gathered from 104 traditional healers (TH) by direct interviews using a semi-structured questionnaire. The calculated use values (UV) were used to analyze the importance of the cited plants.

RESULTS

A total of 99 plant species belonging to 88 genera and 49 families were cited by the TH as curing the hepatic diseases. The most represented families were Caesalpiniaceae with 8 species, followed by Euphorbiaceae with 7 species, Apocynaceae and Asteraceae with 6 species each. The highest UV were recorded with Gomphrena celosioides (0.13), Xylopia ethiopica (0.12), Senna occidentalis (0.12), Bridelia ferruginea (0.12), Cymbopogon citratus (0.12), Kigellia Africana (0.09), Cassia sieberiana (0.08) and Sanseviera liberica (0.08), showing their importance in the management of liver dysfunction in the surveyed region. The main used parts were the leaves, followed by the roots, the whole plant, the rhizome and the bark, accounting for more than 10% each. The herbal medicines were mostly prepared in the form of decoction and administrated by oral route.

CONCLUSION

This study showed that Maritime region of Togo has an important plant biodiversity that is exploited by the indigenous TH. However, some plants cited by the TH have not been studied for their possible hepatoprotective effects. These plants are therefore a starting point for biological screenings.

Anti-diabetic effect of Xylopia aethiopica (Dunal) A. Rich. (Annonaceae) fruit acetone fraction in a type 2 diabetes model of rats

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional medicine from West Africa, the fruit decoction of Xylopia aethiopica (Dunal) A. Rich. is widely used for the treatment of diabetes mellitus (DM) either alone or in combination with other plants. The present study is designed to investigate the anti-diabetic effects of X. aethiopica acetone fraction (XAAF) from fruit ethanolic extract in a type 2 diabetes (T2D) model of rats.

MATERIALS AND METHODS

T2D was induced in rats by feeding a 10% fructose solution ad libitum for 2 weeks followed by a single intraperitoneal injection of streptozotocin (40 mg/kg body weight) and the animals were orally treated with 150 or 300 mg/kg body weight (bw) of the XAAF once daily for four weeks.

RESULTS

After 4 weeks study period, diabetic untreated animals (DBC) exhibited significantly higher serum glucose, serum fructosamine, LDH, CK-MB, serum lipids, liver glycogen, insulin resistance (HOMA-IR), AI, CRI and lower serum insulin, β-cell function (HOMA-β) and glucose tolerance ability compared to the normal animals. Histopathological examination of their pancreas revealed corresponding pathological changes in the islets and β-cells. These alterations were reverted to near-normal after the treatment of XAAF at 150 (DXAL) and 300 (DXAH) mg/kg bw with the effects being more pronounced in the DXAH group compared to the DXAL group. Moreover, the effects in the animals of DXAH group were comparable to the diabetic metformin (DMF) treated animals. In addition, no significant alterations were observed in non-diabetic animals treated with 300 mg/kg bw of XAAF (NXAH).

CONCLUSION

The results of our study suggest that XAAF treatment showed excellent anti-diabetic effects in a T2D model of rats.