In vivo, ex vivo and in vitro Mucoadhesive Strength Assessment of Potential Pharmaceutical Bio-resource Polymer from Diospyros melonoxylon Roxb seeds

In this study, an oral bio-based mucoadhesive polymer was developed from Diospyros melonoxylon Roxb (Ebenaceae) seed mucilage and evaluated for mucoadhesive strength. The mucilage showed shear stress results (0.140 ± 0.0007N), with comparable adhesiveness to HPMC E5 (0.098 ± 0.0008N). Force of adhesion required to detach the seed mucilage and HPMC E5 tablets from the mucin of intestinal tissue were 0.0509 ± 0.0007 (N) and 0.0049 ± 0.0006 (N). Seed mucilage revealed significant higher detachment time, erosion time, in vitro wash off time and ex vivo residence compared to HPMC E5 and lactose tablets (p<0.01). In vivo test indicated that seed mucilage tablets possessed good mucoadhesive strength compared to HPMC E5 and resisted disintegration for ≤ 8 h. The swelling index and wetting time showed comparable results between the mucilage and synthetic polymer tablets. Mucilage demonstrated high moisture absorption, percentage hydration, and matrix erosion of 20.0 ± 0.037, 53.66 ± 0.127, and 20.00 ± 0.077 compared to HPMC E5 10.0 ± 0.079, 36.00 ± 0.089, and 1.26 ± 0.085. The mucoadhesive properties of seeds mucilage were comparable to guar gum and HPMC E5. Thus, seed mucilage of D. melonoxylon can be exploited for usage as pharmaceutical excipient in oral bioadhesive drug delivery systems.