Cross-linking effect of polyphenolic extracts of Lepidium sativum seedcake on physicochemical properties of chitosan films

Lepidium sativum seedcake phenolic extract (LSE), as compared to tannic acid (TA), was evaluated for its effect on film forming ability of chitosan. The films were investigated for their structural, mechanical, optical, thermal and in vitro antioxidant activity release profile. At 5% (v/v of film-forming solution), LSE led to improved 32.2% of tensile strength and 109% elongation, compared to the effect of TA in chitosan films. Moisture content, WVP, and crystallinity decreased with the increasing LSE concentration. Changes in absorbance intensity by FT-IR indicated structural modification. The DSC thermograph indicted a change in the melting point. SEM showed smooth and homogeneous surface cross-section composite film with LSE. The films exhibit dose-dependent and time dependent release of total polyphenols and antioxidant activity in the water, 50% ethanol, and 95% ethanol. Hence, the current work help valorization of L. sativum seedcake after oil extraction for an alternative as novel active-packaging material for food and pharmaceutical application. (C) 2018 Elsevier B.V. All rights reserved.