Appetite Suppressing Activity of Rumex Usambarensis Leaf and Stem Aqueous Extract in Wistar Albino Female Rats: an in vivo Experimental Study.

Background: The burden of obesity and overweight associated morbidity and mortality is increasing in epidemic proportions worldwide. Suppression of appetite is one of the mechanisms that has been shown to reduce weight. Most of the drugs on the market currently for appetite suppression are not readily available or affordable in resource-limited settings. Additionally, previous studies have shown that most of these drugs are associated with significant adverse effects, which demonstrates a need for alternative or complementary options of drugs for appetite suppression. In Uganda, herdsmen commonly chew the raw stems and leaves of Rumex usambarensis, a wild shrub, and this is believed to reduce hunger. This study aimed at determining the effect of Rumex usambarensis aqueous extract on food intake as a measure of appetite in Wistar albino rats. Methods: This study was carried out in two phases: the fattening phase and the treatment phase. Female albino Wistar rats were fed a high-fat diet for 49 days. The fattened animals were then randomly separated into 4 groups, which received 1 mL of distilled water (negative control), 500 mg/kg body weight of aqueous extract of Rumex usambarensis, 1000 mg/kg body weight of the extract and 20 mg/kg body weight topiramate (positive control), respectively. Food intake was measured every day, and weights were taken every two days for every group. Results: Rumex usambarensis extract significantly reduced body weight of fattened rats compared to the control group at both doses: for the 500mg/kg dose (Mean difference, MD = 17.2, p < 0.001) and for 1000mg/kg dose (MD = 25.9, p < 0.001). Additionally, both doses of the aqueous extract showed a significant reduction in food intake: for the 500mg/kg dose (MD = 16.1, p < 0.001) and for the 1000mg/kg dose (MD = 37.3, p < 0.001). There was a strong correlation between food intake and weight for both doses for the 500mg/kg dose (r = 0.744, p = 0.009), and the strongest association observed with 1000mg/kg dose (r = 0.906, p < 0.001). Conclusion: The aqueous extract of the leaves and stems of Rumex usambarensis has appetite suppressing and weight reduction effects in fattened female Wistar albino rats and could be an efficacious alternative medicine for management of overweight, obesity and other related disorders.

Metabolite Profiling and Bioactivities of Leaves, Stems, and Flowers of Rumex usambarensis (Dammer) Dammer, a Traditional African Medicinal Plant.

The comprehensive identification of secondary metabolites represents a fundamental step for the assessment of bioactivities and pharmacological properties of traditional herbal drugs. Rumex usambarensis (Dammer) Dammer has been described as a multipurpose remedy in different African traditional pharmacopoeias, but its phytochemical profile has not been properly investigated. Herein we report a high throughput metabolomic screening, based on ultra-high performance liquid chromatography-travelling wave ion mobility spectrometry quadrupole time-of-flight (UHPLC-TWINS-QTOF), which was performed for the first time on different R. usambarensis plant parts. By applying high-resolution mass spectrometry-based metabolomics and chemometric analysis, a complete discrimination of different aerial parts was obtained, with the annotation of 153 significant metabolites in leaves, stems, and flowers, suggesting an easy authentication and discrimination route. Phytochemical data were correlated to antimicrobial and antioxidant properties. Flavonoids, benzopyranes, chromones, and xanthones derivatives, along with a richer phytocomplex, might be responsible for the stronger bioactivities obtained from flowers.

Influência alelopática do extrato aquoso de raiz de Sapindus saponaria L. sobre capim-arroz e corda-de-viola / Allelopathic influence of aqueous extract of Sapindus saponaria L. root on barnyardgrass and morningglory

O objetivo deste trabalho foi avaliar o potencial alelopático do extrato aquoso de raiz de Sapindus saponaria L. (sabão-de-soldado) sobre a germinação de diásporos e crescimento de plântulas de Echinochloa crus-galli (L.) Link (capim-arroz) e Ipomoea grandifolia (Dammer) O'Donell (corda-de-viola). O extrato aquoso foi preparado na proporção de 100 g de material vegetal seco para 1000 mL de água destilada, produzindo-se a concentração de 10%. A partir dele, foram feitas diluições em água destilada para 7,5, 5,0 e 2,5%. O extrato da raiz de S. saponaria não inibiu a germinabilidade dos diásporos de capim-arroz e corda-de-viola. A maior atividade alelopática ocorreu sobre o crescimento das plântulas, sendo evidenciado pelo alto índice de plântulas anormais, pela redução no comprimento da parte aérea e, principalmente, no comprimento da raiz. O efeito inibitório foi dependente da concentração e variou de acordo com a espécie receptora estudada.

The aim of this study was to evaluate the allelopathic potential of aqueous extract of Sapindus Saponaria L. (soapberry) root on diaspore germination and seedling growth of Echinochloa crus-galli (L.) Link (barnyardgrass) and Ipomoea grandifolia (Dammer) O'Donell (morningglory). The aqueous extract was prepared in a proportion of 100 g of dry plant material in 1000 mL of distilled water, resulting in 10% concentration. The dilutions were made with distilled water to 7.5, 5.0 and 2.5%. The root extract of S. saponaria did not inhibit the germination of the barnyardgrass and morningglory diaspores. The highest allelopathic activity occurred on seedlings growth, being evidenced by the high rate of abnormal seedlings, reduction in shoot length and mainly on root length. The inhibitory effect was concentration-dependent and varied with the receptor species studied.