Background/Objective: Euphorbia hirta, Citrus aurantifolia and Heterotis rotundifolia are commonly used in Benin in the treatment of infectious diseases. The aim of this study is to evaluate the anti-inflammatory, analgesic and antipyretic properties of ethanolic extracts of these plants. Materials and Methods: The study was carried out on 30 wistar rats placed in 6 work lots. A positive control lot having received diclofenac and a negative control lot having received physiological water were used. The ethanolic extract of the plants was used at a dose of 200 mg / kg bw. The model of inflammatory edema of the rat paw induced by 2% formalin was used. Analgesic activity was assessed by the pain method induced by 3% acetic acid and the tail immersion method with wistar rats. The antipyretic effect was evaluated on pyrexia induced by brewer's yeast at 20% with wistar rats. Results: After injection of formalin to animals, inflammatory reaction was almost immediate with appearance of classic signs of acute local inflammation (Redness, pain, heat and edema) at the five experimental groups. This inflammatory reaction occurs in two phases. The first phase occurs between 0 and 2 hours after injection of phlogogenic agent and the second phase, initiated after two hours extending to the fifth hour and even beyond. Administration of these extracts prevents edema inflammatory and inhibition percentages of edema vary between 23.67% and 86.76% for the three extracts. These extracts have similar anti-inflammatory activity (p> 0.05) to that of diclofenac at 50 mg/kg. Analgesic activity show that these extracts inhibit very significantly (p<0.001) chemical pain induced by acetic acid and the highest inhibition percentage is 60.34% (Citrus aurantifolia). This percentage is like to that of acetylsalicylic acid (67.35%) administered at the same dose. Likewise, these extracts attenuate significantly (p <0.05) thermal pain induced by tail immersion of each rat in hot water at 50°C. Indeed, these extracts, reduces very significantly (p <0.001) pyrexia induced by 20% beer yeast suspension in rats and they have similar effect (p> 0.05) to that of acetylsalicylic acid at the fourth hour. Conclusion: These results show that the plants studied have the pharmacological properties evaluated. These results justify the use of these plants in traditional medicine.

Since the time of our ancestors, natural products issued from plant play a therapeutic crucial role. About 25-30% of all medicines (drugs) available for the treatment of diseases are derived from natural products (from plants, animals, bacteria and fungi) or are derivatives of natural products. The aim of this research was to scientifically identify and supply tangible documentation on these two plants employed in the traditional medicine. From November 2020 to February 2021, an ethnobotanical survey was conducted within four markets at the south of Benin, employing a semistructured questionnaire. Two hundred respondents including 80% of females and 20% of males were interviewed. The 2 studied plants are mainly used for different types of sickness related to infections. Females’ herbalists are the most represented. From this research, it appears that the 2 plants are widely used for the treatment of severe infections. On the market, 95% of the leafy steam are sold against 5% of the roots for both plants. The main preparation way is decoction. Oral use is reported to be common in all region. The value of samples sold varies from 200F CFA (Financial Cooperation of Africa) to 1000F CFA. The decoctions are usually obtained through one of a mix of different types of plants. Traditional knowledge is transmitted from one generation to another by oral education. Till today there was no record found. During our study, we did no record prohibition or side effect related to these plants’ use. These medicinal plants occupy a crucial place within the therapeutic arsenal of west Africa. Our results constitute a vital tool to determine the true potentials of these plants. These results could lead to new improved traditional medicine.

Objective Euphorbia hirta , Citrus aurantifolia and Heterotis rotundifolia are commonly used in Benin in the treatment of infectious diseases. The aim of this study is to evaluate the anti-in ammatory, analgesic and antipyretic properties of ethanolic extracts of these plants. The study was performed on wistar rats with 200 mg/kg b.w.Results Administration of these extracts prevents edema in ammatory induced by 2% formalin in rat paw. Inhibition percentages of edema vary between 23.67% and 86.76% for the three extracts. These extracts have similar anti-in ammatory activity (p> 0.05) to that of diclofenac at 50 mg/kg. Analgesic activity show that these extracts inhibit very signi cantly (p<0.001) the pain induced by 3% acetic acid and the highest inhibition percentage is 60.34% (Citrus aurantifolia ). This percentage is like to that of acetylsalicylic acid (67.35%) administered at the same dose. Likewise, these extracts attenuate signi cantly (p <0.05) the thermal pain induced by tail immersion of each rat in hot water at 50°C. Indeed, these extracts, reduces very signi cantly (p <0.001) pyrexia induced by 20% beer yeast suspension in rats and they have similar effect (p> 0.05) to that of acetylsalicylic acid at the fourth hour. These results prove, some traditional therapeutic indications of these plants.