Grewia gum is a polysaccharide derived from the inner stem bark of the edible plant Grewia mollis. Juss (family Tiliaceae). It is a savanna shrub that grows wildly but is usually cultivated in Nigeria and Northern part of Cameroon. The main goal of the present study was to investigate the effect of aqueous extraction conditions on the extraction yield and physicochemical properties of the Grewia mollis. The studied aqueous extraction variables were water/powder (W/P) ratio (10？:？1–80？:？1？w/p), temperature (25.0–85.0°C), time (1–3？h), and pH (4.0–10.0). The results indicated that the aqueous extraction variables exhibited the least significant ( ) effect on the yield and the viscosity of the gum. The result shows that the ratio of extraction is the main factor affecting the extraction of gum. The optimized extraction condition for higher viscosity was at the powder/water ratio of 1？:？55.4, pH of 7, time of 1？h, and temperature of 50°C. However, the optimized extraction condition for higher yield was at the powder/water ratio of 1 : 80, pH of 4, time of 3？h, and temperature of . 1. Introduction Grewia mollis is a shrub or tree widely distributed in Sudano-Sahelian region and found in Cameroon and Nigeria. The dried and pulverized inner stem bark is used as a thickening agent in some local dishes [1]. In the Adamawa region of Cameroon in particular, the powder is used as binding agent in the preparation of maize fried cake. This functionality is also exploited in Nigeria where it is used in cooking soup, or dried and pulverized to mix with bean meal to make cakes locally called in Hausa “Kosai” [2]. The functional properties of Grewia powder have been associated with the presence of mucilage, a polysaccharide nature [3]. In addition, the mucilage of the bark is used traditionally by the Yoruba people of Nigeria at child birth [2]. Phytochemical studies on the leaves and stem bark of Grewia mollis indicate the presence of tannins, saponins, flavonoids, glycosides, phenols, and steroids and the absence of alkaloids [4]. In overall and in the limit of our knowledge, the literature on Grewia reported mainly the evaluation of the performance of fine powder of stem bark as binders substitute in tablet formulation [2] and the toxic effect of the powder on experimental rats [5]. Results revealed that Grewia gum compares favorably with the standard binder Polyvinylpyrrolidone (PVP) and could be a useful substitute binder in paracetamol tablet formulations [2]. In addition consumption of Grewia powder by rat models showed no significant effect on serum alkaline
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