andardization, Phytochemistry and Antidiarrhoeal activities of Alstonia boonei De Wild. And Alstonia congensis ENGL. Stem barks

The apparent similarities between Alstonia boonei (AB) and Alstonia congensis (AC), could lead to misidentification and inappropriate medicinal utilization. This study aimed at evaluating pharmacognostic and anti-diarrheal profiles of the stem barks of these species for the establishment of their pharmacopoeial standards. Micro-morphologically, A. boonei and A. congensis stem barks have prismatic calcium oxalate crystals, cork, phellogen, and stone cells. A. boonei stembarks have osteosclerotic stone cells while A. congensis had brachysclereid type. The moisture content value of the tem bark of AB (6.4 ± 0.06%) was significantly different from that of AC (7.2 ± 0.4%). Elemental analysis revealed that calcium in the stem barks of AB (52.2 ± 1.2 mg/g) and AC (39.7 ± 1.0 mg/g). The ABSD (200 mg/kg b.w.) showed significant anti-diarrheal activity (87.3%) comparable to the standard (Loperamide; 87.5%). The diagnostic characteristics obtained in this study can be used to differentiate between Alstonia boonei and Alstonia congensis stembarks when they are used as antidiarrhea.