Antidiarrheal activity of methanolic extract of the root bark of Cordia africana

Review of Medicinal Plants Traditionally Used to Treat Diarrhea by the People in the Amhara Region of Ethiopia

Background

Diarrheal illness is the second-most common cause of death in under-five children. Worldwide, it results in about 1.7 billion illnesses and 525,000 deaths among under-five children annually. It is the leading cause of malnutrition among under-five children. Different people use medicinal plants to treat diarrhea. The present study aimed to review the medicinal plants used to treat diarrhea by the people in the Amhara region and to diagnose whether the antidiarrheal activities of the medicinal plants have been confirmed by studies using animal models.

Methods

The author searched 21 articles from worldwide databases up to December 2022 using Boolean operators ("AND" and "OR") and the terms "ethnobotanical studies," "ethnobiology," "traditional medicine," "ethnobotanical knowledge," and "Amhara region."

Results

From the 21 studies reviewed, 50 plant species grouped into 28 families were reported to treat diarrhea by the people in the Amhara region. The top most used families were Lamiaceae (12%), Fabaceae (8%), Asteraceae, Cucurbitaceae, Euphorbiaceae, and Poaceae (6% each). The modes of administration of the plant parts were orally 98.88% and topically 1.12%. The different extracts of 18 (or 36%) of the medicinal plants traditionally used to treat diarrhea by the people in the Amhara region have been proven experimentally in animal models.

Conclusions

The people in the Amhara region use different medicinal plants to treat diarrhea. Most of them take the medicinal plants orally. The traditional claim that 60% of medicinal plants are antidiarrheal has been confirmed in in vitro studies.

Flavonoids and Phenolic Acids from Aerial Part of Ajuga integrifolia (Buch.-Ham. Ex D. Don): Anti-Shigellosis Activity and In Silico Molecular Docking Studies

Shigellosis is one of the major causes of death in children worldwide. Flavonoids and phenolic acids are expected to demonstrate anti-shigellosis activity and anti-diarrheal properties. The aerial part of A. integrifolia is commonly used against diarrhea. This study aimed to identify flavonoids and phenolic acids responsible for this therapeutic purpose. Antioxidant activity, total phenol content, and total flavonoid content were determined. The antibacterial activity of the aerial part against Shigella spp. was also tested using the agar well diffusion method. HPLC analysis was performed using UHPLC-DAD for different extracts of the aerial part. Autodock Vina in the PyRx platform was used to screen responsible components. Ciprofloxacin was used as a reference drug. An enzyme taking part in pyrimidine biosynthesis was used as a target protein. Molecular docking results were visualized using Discovery Studio and LigPlot1.4.5 software. Antioxidant activity, total phenol content, and total flavonoid content are more significant for the aerial part of A. integrifolia. From HPLC analysis, the presence of the flavonoids, quercetin, myricetin, and rutin and the phenolic acids gallic acid, chlorogenic acid, and syringic acid were identified from the aerial part of A. integrifolia. Regarding the antibacterial activity, the aerial part shows considerable activity against Shigella spp. Binding energies, RMSD and Ki values, interaction type, and distance are considered to identify the components most likely responsible for the therapeutic effects and observed activity. Antioxidant activity, total phenol content, and total flavonoid content of the aerial part are in line with anti-shigellosis activity. The top five components that are most likely potentially responsible for therapeutic purposes and anti-shigellosis activity are chlorogenic acid, rutin, dihydroquercetin, dihydromyricetin, and kaempferol.

Evaluation of Antidiarrheal Activity of 80% Methanolic Extract of the Leaves of Cordia africana (Lamiaceae) in Mice

Background

Diarrheal disease is a major cause of morbidity and mortality throughout the world, particularly in developing countries. Currently available drugs are linked with adverse effects, contraindications, and risk of resistance. Traditionally, the leaf concoction of Cordia africana is claimed to be used for diarrhea. However, the safety and efficacy of the leaf extract have not been scientifically approved yet. Therefore, the study was conducted to validate its antidiarrheal activity and safety profile in mice.

Method

The hydromethanolic extract was obtained by the cold maceration technique in 80% methanol. Phytochemical screening tests were done for secondary metabolites by using standard tests. The antidiarrheal activity of the test extract at the doses of 100, 200, and 400 mg/kg was evaluated by using castor oil-induced diarrheal, gastrointestinal transit, and enteropooling models in mice.

Result

In an acute toxicity study, there were no visible signs of toxicity and mortality following a single oral administration of 2000 mg/kg. Phytochemical screening tests revealed the presence of alkaloids, saponins, flavonoids, terpenoids, phenols, and tannins. The hydromethanolic extract significantly prolonged the onset of diarrhea and reduced the weight of wet and total feces at 100 (P < 0.01), 200 (P < 0.001), and 400 mg/kg (P < 0.001) in the castor oil-induced diarrheal model. However, in the gastrointestinal transit model, a significant (P < 0.001) reduction in the charcoal meal travel was observed in the middle (200 mg/kg) and higher (400 mg/kg) test doses. Similarly, the extract produced a significant (P < 0.001) reduction in the weight and volume of intestinal contents at the aforementioned doses.

Conclusion

The study demonstrated that the test extract showed promising antidiarrheal activity. Hence, this study supports its antidiarrheal use in Ethiopian folklore medicine.

Methanolic Crude Extract of Hagenia abyssinica Possesses Significant Antidiarrheal Effect: Evidence for In Vivo Antidiarrheal Activity

Background

Hagenia abyssinica is one of the most commonly used medicinal plants for the treatment of diarrhea in Ethiopia. Therefore, this study aimed to evaluate the antidiarrheal effect of methanol crude extract of H. abyssinica leaves in mice.

Methods

Acute toxicity testing was conducted using Organization for Economic Cooperation and Development guidelines. The antidiarrheal activity of the crude extract of H. abyssinica was investigated using three animal models such as small intestine transit, enteropooling, and castor oil-induced diarrhea models. The extract was administered at three different doses (100, 200, and 400 mg/kg) to the test groups, while the positive control group received 3 mg/kg of loperamide and the negative control group received 10 ml/kg of vehicle (distilled water).

Results

The crude extract of H. abyssinica did not exhibit death at the limit dose (2 g/kg) throughout the observation period. In the castor oil-induced model, the crude extract at a dose of 200 and 400 mg/kg exhibited a significant (P < 0.05) antimotility effect as compared to the negative control. The crude extract revealed a significant reduction in the volume and weight of intestinal contents at 200 and 400 mg/kg doses of the extract. Moreover, the highest antidiarrheal index (ADI) was obtained with the dose of 400 mg/kg of crude extract, which was comparable to the standard drug.

Conclusion

The crude extract of Hagenia abyssinica possesses antidiarrheal activity and supports the traditional use of H. abyssinica for the management of diarrhea.

Evaluation of In Vivo Antidiarrheal Activity of Solvent Fractions of Hagenia abyssinica (Rosaceae) in Swiss Albino Mice

Background

Ethiopia has several medicinal plants that have been used for their antidiarrheal activity. Hagenia abyssinica is the most commonly used medicinal plant for the management of diarrhea in Ethiopia. Thus, this study's aim is to investigate the antidiarrheal effect of solvent fractions of H. abyssinica.

Methods

Antidiarrheal activity of extract fractions obtained from different solvents was evaluated by using small intestine transit, enteropooling, and castor oil-induced diarrhea animal models. In all animal models, the solvent fractions treated groups were treated with three different doses (100 mg/kg, 200 mg/kg, and 400 mg/kg) of the solvent fractions, while the negative control group was treated with a vehicle (distilled water), and positive control group was treated with loperamide.

Results

The acute toxicity test revealed that the LD₅₀ of H. abyssinica is > 2000 mg/kg. In castor oil-induced, the solvent fractions of H. abyssinica (at 200 mg/kg and 400 mg/kg) significantly (P < 0.05–0.001) prolonged the stool frequency, reduced the weight of feces, and delayed diarrheal onset time as compared with the negative control group. The fractions produced a significant (P < 0.05) antimotility effect at the doses of 200 mg/kg and 400 mg/kg as compared to the negative control. All solvent fractions at the middle and higher doses showed a statistically significant dose-dependent reduction in the volume of intestinal contents and weight of the feces. However, the solvent fractions of H. abyssinica at a dose of 100 mg/kg failed to produce a statistically significant activity in all parameters (number of wet feces, the onset of diarrhea, and number of total feces) when compared with the negative control group.

Conclusion

The extract fractions obtained from different solvents have shown significant antidiarrheal activity. Thus, this finding supports the claimed traditional use of H. abyssinica leaves for the treatment of diarrhea.

Phytochemical and Antiulcer Activity Screening of Seed Extract of Cordia africana Lam (Boraginaceae) in Pyloric Ligated Rats

Introduction

Peptic ulcer disease represents a worldwide health problem because of its high morbidity, mortality and economic loss. It is a very prevalent condition affecting around 10%–15% of the general population worldwide. Most of the available antiulcer drugs are costly and have an incidence of relapse, drug interactions and several side effects upon chronic usage. Hence, the use of herbal medicine may be safe, economical and effective in such cases when drugs are used for long periods. Ethnobotanical reports showed traditional claims on the use of Cordia africana seeds for the treatment of gastric ulcers. However, the safety and efficacy of these remedies are not well known. The aim of this study is, therefore, to evaluate the antiulcer activity and safety of a crude extract of C. africana seeds in animal models.

Methods

Shade-dried seeds of C. africana were extracted by 80% methanol and dried by the rotator evaporator and lyophilized. The crude extract was used to evaluate antiulcer activity in vivo with pylorus ligation method, on Wistar albino rats weighing 230–250g. Preliminary phytochemical screening was performed using a standard procedure. Acute toxicity study was carried out in Swiss albino mice before antiulcer activity tests.

Results

No sign of toxicity was observed upon the administration of 2000 mg/kg of the crude extract to mice. Single-dose administration of 400 and 600 mg/kg extract showed a significant reduction in the volume of secretion and acidity of the stomach (p <0.01). The doses 400 and 600 mg/kg have reduced the ulcer score by 83.58% and 88%.

Conclusion

The result of this study showed that the hydromethanolic crude extract of C. africana has strong antisecretory and ulcer protective activities against ulcers produced by pylorus ligation.

Antidiarrheal Activity of Hydromethanolic Root Extract and Solvent Fractions of Clutia abyssinica Jaub. & Spach. (Euphorbiaceae) in Mice

Introduction

Diarrheal diseases are associated with an estimated 1.3 million deaths annually, with most occurring in resource-limited countries; up to 25% of deaths in young children living in Africa and southeast Asia are attributable to acute gastroenteritis. Due to limitations associated with various treatments available, the need for developing newer drugs is imperative.

Objective

This study was aimed to evaluate the antidiarrheal activity of root extract and fractions of C. abyssinica Jaub. & Spach. (Euphorbiaceae) in mice.

Methods

After plant extraction and subsequent fractionation of the crude extract, the antidiarrheal activity was screened in castor oil induced diarrhea, castor oil induced enteropooling, and gastrointestinal motility test models accordingly.

Result

The root extract of C. abyssinica produced neither visible signs of toxicity nor death at a single dose of 2000 mg/kg, suggesting the LD₅₀ > 2000 mg/kg. In the castor oil induced diarrheal model, the highest dose of the extract (400 mg/kg) showed a maximal inhibition in the onset (158.00 ± 14.64, p < 0.01, in minutes) of wet feces as compared to the negative control. In the enteropooling model, 400 mg/kg treated mice showed a significant reduction in volume (0.47 ± 0.02 ml, p < 0.01) and weight (0.50 ± 0.02 g, p < 0.05) of intestinal content as compared to the vehicle treated group. In the gastrointestinal motility test, the hydromethanolic root extract of C. abyssinica significantly inhibited the intestinal transit of charcoal meal at 400 mg/kg. In addition, chloroform and n-butanol fractions significantly reduced the distance moved by charcoal at doses of 200 mg/kg and 400 mg/kg, whereas aqueous fraction showed a significant effect at all test doses. The highest antidiarrheal index was observed at the maximal dose of extract and each fraction.

Conclusion

The results obtained showed that the findings provide scientific support for the folkloric repute of C. abyssinica roots as treatment of diarrhea.

Antimalarial Activity of Cordia africana (Lam.) (Boraginaceae) Leaf Extracts and Solvent Fractions in Plasmodium berghei-Infected Mice

Background

Malaria remains a major worldwide public health problem leading to death of millions of people. Spread and emergence of antimalarial drug resistance are the major challenge in malaria control. Medicinal plants are the key source of new effective antimalarial agents. Cordia africana (Lam.) is widely used for traditional management of malaria by local people in different parts of Ethiopia. The present study aimed to evaluate in vivo antimalarial effects of leaf extracts and solvent fractions of Cordia africana on Plasmodium berghei-infected mice.

Methods

The leaf extracts were prepared and tested for oral acute toxicity according to the OECD guideline. In vivo antimalarial effects of various doses of C. africana extracts and solvent fractions were determined using the four-day suppression test (both crude and fractions), as well as curative and chemoprophylactic tests (crude extracts).

Results

The acute toxicity test of the plant extract revealed that the medium lethal dose is higher than 2000 mg/kg. The crude extract of the plant exhibited significant parasitemia suppression in the four-day suppression (51.19%), curative (57.14%), and prophylactic (46.48%) tests at 600 mg/kg. The n-butanol fraction exhibited the highest chemosuppression (55.62%) at 400 mg/kg, followed by the chloroform fraction (45.04%) at the same dose.

Conclusion

Our findings indicated that both the crude leaf extracts and fractions of C. africana possess antimalarial effects, supporting the traditional claim of the plant.

Medicinal Plants Used for Treatment of Diarrhoeal Related Diseases in Ethiopia

This paper presents a review of relevant antidiarrhoeal medicinal plants based on the fundamental knowledge accumulated by indigenous people of Ethiopia. The review includes an inventory carried out on the phytochemical and pharmacological analysis of plant species used in the treatments of diarrhoeal diseases. This study is based on a review of the literature published in scientific journals, books, theses, proceedings, and reports. A total of 132 medicinal plants used by local people of Ethiopia are reported in the reviewed literature. Herbs (43.6%) were the primary source of medicinal plants, followed by trees (27%). Some findings include the predominance of leaf material used (78%), as well as the frequent use of crushing of the plant parts (38%) as a mode of preparation. This study demonstrates the importance of traditional medicines in the treatment of basic human ailments such as diarrhoeal diseases in Ethiopia. Baseline information gaps were observed in different regions of Ethiopia. Thus, documentation of the knowledge held by other regions of Ethiopia that have so far received less attention and urban ethnobotany is recommended for future ethnobotanical studies. In addition, phytochemical studies are recommended mainly on frequently utilized medicinal plants for treatment of diarrhoeal diseases which can serve as a basis for future investigation of modern drug development. Although societies in Ethiopia have long used medicinal plants for diarrhoeal diseases treatment, it is also a good practice to perform toxicological tests.