The World Health Organization (WHO) defines overweight and obesity as adults with a Body Mass Index (BMI) ≥ 25 Kg/m² and a BMI ≥ 30 Kg/m², respectively [1] . According to the World Obesity Federation in 2024, among the 41 million adult deaths each year due to non-communicable diseases, 5 million are due to a high BMI (≥ 25 kg/m²). The prevalence of obesity was 36.5% among U.S. adults during 2011-2014; the prevalence of obesity among women (38.3%) was higher than among men (34.3%) [2] . By 2035, more than half the world’s population will be overweight. Most of these people will be in middle-income countries, where obesity is often poorly understood and there is a lack of resources to combat it [3] . In Burkina Faso, 13.4% of the population aged between 25 and 64 years old was overweight, and the prevalence of obesity was 4.5% for this population group [4] . Obesity increased notably from 2000 to 2016 (+3%) in adults. Furthermore, the country is among the top 20 countries where the proportion of children living with a high BMI increased most rapidly from 2000-2016 [3] . The main causes are hereditary or genetic predisposition, excessive food consumption, stress, sedentary lifestyle [5] . High-calorie foods are gradually replacing traditional African diets and a more sedentary lifestyle, leading to a greater prevalence of obesity and chronic diseases such as cardiovascular disease, diabetes, cancer, neurological disorders, chronic respiratory disease, and digestive disorders [6] .

The main approaches used to treat obesity are the reduction of dietary ingesta by curbing appetite with appetite-suppressants, stimulating energy expenditure by increasing basal metabolism energy expenditure, and increasing calorie loss by inhibiting intestinal fat absorption [7] . The approach that has long been used in treating obesity is to reduce food intake with appetite suppressants that act at the central level [8] . According to Neary et al., in 2004, food restriction is the first-line treatment for obesity [9] . The majority of current pharmaceutical anti-obesity drugs and effective drugs act by reducing food consumption [10] . These drugs, categorized as appetite suppressants, deceive the body’s central nervous system into believing it is not hungry. Unfortunately, most of the anti-obesity drugs developed since the 1950s, particularly those that target the brain amines to decrease appetite, have been withdrawn for reasons of ineffectiveness or cardiovascular (stroke, effect on blood pressure and heart attack), neuropsychiatric (depression, sleep disorders, anxiety, nervousness, irritability, and aggression) and gastrointestinal (nausea or diarrhea, constipation) disturbances [8] [11] . More effort is needed to develop new drugs to combat obesity. To remedy this impasse, Scheen et al., in 2023, recommended different therapeutic combinations, with complementary to be sufficiently compelling [7] .

Phytomedicines could also be an alternative because they are well-tolerated, effective, less expensive, economical with easy availability. The effective use of these plants could improve the disorders associated with obesity because they act on multiple targets [11] . For example, some plants have been studied for their ability to regulate food intake. These include Phaseolus vulgaris, Celastrus requelii, Camellia sinensis, Garcinia cambogia, Hoodia gordonii, Amorphophallus konjac and Caralluma fimbriata [12] - [14] . Appetite-suppressant plants are among the drugs recommended or used for weight-loss dietary supplements [15] . Limited effectiveness and side effects of centrally acting appetite suppressants encourage the search for new peripheral-acting appetite suppressants. Our context does not have much information about plants that suppress appetite.

According to ethnobotanical surveys conducted by Zongo et al., in 2022 and Paré et al., in 2016, Parkia biglobosa (Jacq.) R.Br. ex G.Don is a plant that could have appetite suppressant and anti-obesity properties [16] [17] . Parkia biglobosa (Pb) is also used to increase physical performance and is reported to have anxiolytic effects, according to a survey conducted by Sama et al. in 2022, with a citation frequency of 10% [18] . Parkia biglobosa (also known as African locust bean and known locally as ‘Roânga’) is widely known in Africa for its many nutritional benefits and savory taste. It belongs to the Mimosaceae family. The fruit’s pulp is eaten raw and used to make porridge or drinks. The fruit pulp plays an important nutritional role at a time of year when cereals are in short supply. In traditional medicine, the pulp of Pb is used as sedative, diuretic, purgative or antimalarial drug [19] . The anti-obesity properties of Pb fruit pulp have already been mentioned. In fact, Gouveia-Nhanca et al. concluded in 2023 in their experimental study on rats that treatment with fruit pulp is a promising strategy against obesity [20] . The shortcomings of this study were the lack of assessment of acute and long-term food intake following administration of Parkia biglobosa fruit pulp at different doses. To assess the effectiveness of new compounds in discovering anti-obesity drugs, acute food intake models, such as the acute intake model in mice and rats, are currently being used more and more. The acute food intake model is crucial in identifying compounds with potential appetite-suppressant activity and selecting them for further repeated administration studies that aim to reduce body weight [10] [21] . This research evaluated the decrease in acute and long-term food intake induced by Parkia biglobosa fruit pulp administered to healthy mice.

The cause of obesity is a change in the difference in food intake and energy expenditure [10] . The search for compounds that can effectively reduce food intake with good tolerance remains a current research pursuit. In this study, our objective was to demonstrate the appetite-suppressant effect of Parkia biglobosa fruit pulp, a plant previously cited as an appetite-suppressant and anti-obesity in previous studies [16] [17] . The fruit is a vital source for disease management [28] . The anti-obesity potential of these parts is ranked second only to leaves among Table 5. Concentrations of secondary metabolites and antioxidant activity of extracts of Pb fruit pulp.

GAE: Gallic acid equivalent; TAE: Tannic acid equivalent; AAE: Ascorbic acid equivalent; QE: Quercetin Equivalent. Each value represents the mean ± standard deviation (n = 3).

the most widely used plant parts [13] . Fruit-rich diets promote feelings of fullness and delay the return of hunger [15] . Consuming fruit can contribute to weight loss and consuming three fruits a day could reduce energy intake due to greater satiety [29] .

In an acute model, in mice, our study demonstrated that the Pb fruit pulp significantly reduced food intake with the 3 test doses compared to the control group. The 250 mg/kg dose had the best inhibitory activity on acute food intake, with an overall reduction rate of feed intake of approximately 47% compared to the control group at 24 h. Yimam et al., in 2018, in their study of natural appetite suppressant products, observed statistically significant reductions in acute food intake in rats treated with UP601 (230 mg/kg and 350 mg/kg) [21] . The cumulative percentage reduction was 30.9% and 21.4% at 24 h, respectively, with UP601 at 230 mg/kg and 350 mg/kg compared to the control group. UP601 is a composition of extracts of 3 medicinal plants (Magnolia officinalis, Morus alba, and Ilex paraguariens) that could be a potential source of dietary supplements to suppress appetite, maintain weight, and improve metabolism significantly. Yimam et al., in 2016, evaluating the inhibition activity of acute food intake of Morus alba, observed statistically significant reductions in acute and long-term feed intake in mice treated with 250 mg/kg and 500 mg/kg extracts [30] . Reductions were more significant for the 250 mg/kg dose of extracts before 4 h. In 1998, Colombo et al. observed in 24 hours of treatment with a cannabinoid receptor antagonist called “SR 141716”, inhibition of food intake of 25% and 50% with doses of 2.5 mg/kg and 10 mg/kg, respectively, in non-obese rats treated compared to the control group. He concluded that “SR 141716 could be clinically useful in treating obese patients” [31] .

Our study found that after repeated daily administration, the inhibition of food intake of the Pb fruit pulp remained constant for 13 days with the 3 doses. The 100 mg/kg Pb dose exerted the most significant inhibitory effect on food intake for a long time (31 days). Furthermore, the only dose (Pb 100 mg/kg) significantly reduced body weight gain (p = 0.0003) in week 7 compared to the control in healthy mice treated with Pb fruit pulp. These results could suggest the existence of an effective dose of aqueous suspension of Pb fruit pulp to maintain a prolonged appetite suppressant effect and significantly reduce body weight gain. Our results are similar to those of Gouveia-Nhanca et al., in 2023, who demonstrated a reversal of hyperphagia or weight gain in obese rats after long-term daily administration of Pb fruit pulp. Indeed, he observed that treatment with Pb pulp reduced food intake in obese rats during the 8 weeks of intervention [20] . Yimam et al., in 2016, observed 7.4% and 22.5% reductions in body weight gain in obese mice treated with Morus alba extract at doses of 250 and 500 mg/kg compared to obese animals treated with the vehicle at week 7 [30] . Unlike our study, Asoom et al., in 2023, when evaluating the efficacy of Nigella sativa as a natural appetite suppressant, had not observed a significant change in reduced food intake or body weight during long-term administration of Nigella sativa compared to the control group that had received distilled water [32] . The body weights of the treated mice and the control were not significantly different after 3 weeks of dietary fiber treatment, according to Hadri et al. in 2016 [33] .

After repeated daily administration duration, the study findings showed that the effect of reducing food intake decreased and disappeared. Previous studies have made similar findings. Indeed, Yimam et al., in 2016, had already made the same observation regarding the trend of the disappearance of the effect of reducing food intake with repeated administrations of Morus alba root-bark extract over the course of 7 weeks [30] . Colombo et al., in 1998, observed that by continuing the treatment, a tolerance to the appetite suppressant effect of the “SR 141716” had developed rapidly in 5 days in non-obese rats over the 14 days of the experiment [31] . Hadri et al., in 2016, also observed that the anorectic effect of dietary fiber disappears after 2 weeks when it is administered in the form of small meals in treated mice compared to the control group [33] . This could be explained by a decrease in the sensitivity of the receptors involved in the appetite suppressant mechanism or the development of tolerance in mice after long-term daily administration. Indeed, prolonged consumption of foods with a pleasant taste (such as foods high in sugars) can alter the expression of appetite-regulating peptides or induce resistance to satiety signals such as leptin, insulin, and cholecystokinin (CCK) [34] ; hence the overfeeding effect observed with the Pb fruit pulp groups after a long period.

The relative organ weights of the mice treated with Pb pulp showed no significant change (p-value > 0.05) compared to the control group. The reason for these results is that the pulp fraction of the Pb fruit would not have any toxic effect on the organs of the mice when administered daily for 49 days. Hadri et al., in 2016, had the same finding with the liver and kidneys during the administration of dietary fiber [33] . The Pb fruit pulp would have a good tolerance on the organs compared to the three doses used in this experiment. Ngatchic et al. in 2020, also did not observe a significant difference (p > 0.05) in the relative weights of the kidneys, pancreas, lungs, and heart of rats in all groups with the powders of the Dichrostachys glomerata fruit after a 4-week treatment [35] . Fruits, in general, have a good tolerance, and dieticians widely recommend their consumption.

The biochemical results did not show a significant difference (p > 0.05) despite reductions in total cholesterol (TC) and triglyceride (TG) concentrations of the Pb-treated groups compared to the control group. Hadri et al., in 2016, also made the same observation with plasma TGs after administration of 10% fibers during 14 days of treatment in rats [33] . This could be explained by the fact that long-term treatment with Pb fruit pulp has no deleterious effect on carbohydrate or lipid metabolism when mice are treated with a standard diet low in lipid compounds. The results could be different if mice were fed a high-fat diet. According to Hadri et al., in 2016, fiber and protein decreased plasma TGs in the case of a high-fat diet. Indeed, the Pb pulp fruit contains polyphenols that could inhibit pancreatic lipase and promote TG excretion [33] . In addition, these polyphenols can form complexes with cholesterol and bile acids to facilitate its excretion in the stool. Ngatchic et al. in 2020 observed that the group treated with the powder fraction 212-180 μm of Dichrostachys glomerata fruits for 4 weeks resulted in a significant decrease (p < 0.05) in TG concentration in the treated rats compared to the negative control group [35] . This study was conducted on animals fed with a high-fat diet; this was not the case in our study, where the animals were all fed a standard diet for mice. Asoom et al., in 2023, with Nigella sativa as an appetite suppressant, found that the plant significantly reduced cholesterol levels in treated rats compared to the control group after nine weeks of experimentation with high-fat foods [32] . Yimam et al., in 2018, found that UP601 reduced serum concentrations of total cholesterol and triglyceride [10] . A similar study with a high-fat diet in our context could confirm these observed differences.

The results of the nutritional composition and the study of the phytochemistry of the Pb pulp fruit indicate that it is rich in total carbohydrates (68.81%), crude fiber (14.35%), and total phenolics (12.43 and 11.71 mg GAE/100 mg respectively with the methanolic and aqueous extracts). Our results on nutritional values were similar to those of Belem et al. in 2023, who observed low protein (5.11%) and lipid (1.12%) levels and high crude fiber (16.88% and 19.81% respectively in Acid Detergent Fiber and Neutral Detergent Fiber) level in Pb fruit pulp [36] . The Pb fruit is acidic (pH 5.22), and this acidity can influence the activity of certain enzymes. Macronutrients are known to have effects on satiety [33] . Pb fruit pulp is low in fat content. Fat is the least appetite suppressant among macronutrients [33] . The appetite suppressant effect of proteins has recently been shown through μ-opioid receptors, leading to intestinal gluconeogenesis [37] [38] . It seems that when these receptors are overworked, they become insensitive; hence the need to find the best way to inhibit them “moderately,” to maintain their beneficial effect in the long term on the control of food intake. Treatment containing 30 g protein/2 g soluble fiber had the best-prolonged effect on satiety (about 4 hours) compared to the control [39] . This study showed that formulations containing vegetable protein and soluble fiber can control appetite and would be a means of weight management. Unfortunately, Pb fruit pulp contains low protein content. In 2007, Gernah et al. observed a crude fiber level (11.75%) close to ours in the Pb fruit pulp and the presence of total phenolics (204.6 mg/100g) [40] . In 2023, Gouveia-Nhanca et al. observed a higher fiber level (34.47%) in the pulp of the Pb fruit, including 14.40% soluble dietary fiber and 20.07% insoluble dietary fiber [20] . This could be explained by the difference in the methods used for fiber quantification. Nevertheless, these data prove that the Pb fruit pulp is a good source of fiber. A review on herbal medicine for the suppression of energy intake reported that plants suppress appetite because of the high content of dietary fiber they contain, and this effect was only obtained with large quantities [34] . Fiber does not contribute to the energy provided, but it helps prevent certain diseases such as obesity, diabetes, and cancer; hence, their use in weight-loss food supplements. The appetite suppressant plants recommended in pharmacies are mostly plants rich in dietary fiber (gums, mucilage, pectins, alginates) [15] . Fiber increases the viscosity of the food absorbed, increases volume, and slows gastric emptying. The prolonged interaction with the intestinal mucosa will, therefore, promote the secretion of intestinal peptides involved in appetite regulation. The fiber in Pb fruit pulp helps increase satiety through fermentation by the gut microbiota to form short-chain fatty acids, including acetate, propionate, and butyrate [37] [41] [42] [43] . Pb pulp is rich in succinate, which is a substrate for intestinal gluconeogenesis [20] [37] . Acetate reduces acute food intake by acting directly on the central nervous system. Acetate in mice crosses the blood-brain barrier and suppresses hunger through hypothalamic mechanisms. Indeed, acetate induces the expression of anorectic neuropeptides, particularly pro-opiomelanocortin (POMC) [44] . Phenolic compounds can also inhibit the activity of digestive enzymes and reduce fat digestion and prolong the state of satiety [43] [45] . Following food ingestion, a study has shown that proportions of 5 and 10% of polyphenols are absorbed in the intestine. The rest reaches the distal part of the intestine, where they are hydrolyzed by intestinal bacteria [41] . Previous studies have discussed the role of polyphenols in weight management [13] [46] . Bothon’s study showed that the hydroethanolic extract of Parkia biglobosa fruit husks scavenges the DPPH radical [47] . Gouveia-Nhanca et al., in 2023, linked reductions in food intake and weight gain of Pb pulp with its rich composition of fiber, organic acid, and phenolic compounds [20] . These compounds exert metabolic effects on the gut and brain of animals. By analyzing the feces of rats treated with the Pb fruit pulp, Gouveia-Nhanca et al. observed an increase in the concentration of short-chain fatty acids (propionic acid + butyric acid) compared to the control [20] in healthy rats. Propionic acid interacts with the regulation of glucagon-like peptide 1 (GLP1) and peptide YY, hormones that promote the reduction of food intake and the increase in satiety state [48] [49] . Acetate and proprionate are substrates for gluconeogenesis [50] . Propionate from dietary is capable of modifying food intake in mice, but not in rats and all rodents [51] [52] ; this factor could explain the discrepancy between our results and those of Gouveia-Nhanca [20] , who did not observe any significant reduction in food intake in healthy rats. Butyric acid binds to G protein-coupled receptors (GPR41) to drive the production of the anorectic hormone (PYY Peptide) to promote appetite control [53] . Short-chain fatty acids from fruit pulp fibers and phenolic compounds could be responsible for the appetite suppressant effect observed in our study by central and peripheral mechanisms. The study of serum organic acids (acetate, propionic acid + butyric acid) would better understand the mechanism of appetite suppression of Pb fruit pulp in healthy mice after long-term administration. Our study has limitations that should inform future research. Estimation of organic acids and biomarkers of satiety (GLP-1, PYY, CCK, Ghrelin) have helped shed light on the effect in Pb-treated mice.

This study demonstrated that Pb fruit pulp effectively reduces acute food intake in healthy NMRI mice. The long-term evaluation also showed the inhibition effect, but this effect decreased over time and depended on intervention doses. The 100 mg/kg Pb dose significantly reduced food intake over time (31 days) and body weight gain at the end of the seven weeks of intervention in healthy mice. The nutrient composition and phytochemical study of Parkia biglobosa fruit pulp indicate its richness in crude fiber, total carbohydrates, and phenolic compounds. These data strengthen knowledge of the anti-obesity properties, nutritional values, and phytochemicals of Parkia biglobosa fruit pulp. The pulp of the Parkia biglobosa could be a source of food supplements based on natural appetite suppressants to help manage obesity.

We want to thank the team of Institut de Recherche en Sciences de la Santé (IRSS) of Bobo-Dioulasso for the experimental technical platform, the team of Institut de Recherches en Sciences Appliquées et Technologies (IRSAT) of Ouagadougou and Bobo-Dioulasso team for the analyses of nutritional parameters, the team of Laboratoire de Recherche et d’Enseignement en Santé et Biotechnologies Animales (LARESBA) for phytochemical analysis and assessment of antioxidant activity.

EZ, R.NT.M, BK, S.E.K, GA contributed to the design of the study, the validation of the protocol, the writing and correction of the manuscript. YG, CO, OT contributed to the data collection. CO, MN contributed to the analysis and interpretation of the data; EZ OD, WK, HB, DP contributed to the revision of the manuscript. All authors have read and approved the final manuscript.

The authors did not receive any financial support for the research or publication of this article.

The collected data can be shared or accessed with the respective author upon request. This data is entered into an Excel file and is also available in a paper version.

All experimental animal procedures have been performed following the Guide for the Care and Use of Laboratory Animal of the US National Institutes of Health and the EU Directive 2010/63/EU for animal experiments [54] . The study protocol was approved by the local ethics.