Abstract

ENZYMATIC DEGRADATION OF GLIADIN BY NIGELLA SATIVA SEEDS PROTEASE: IMPLICATIONS FOR NEW TREATMENT OF CELIAC DISEASE

Nousseiba ABED*, Mohamed Nacer Bellir, Douadi Khlifi, Ines Bellil, Asma Medouri, Imane Medoukali, Leila Rouabah 

ABSTRACT

The protease was extracted from Nigella sativa seeds with 0,1 M citrate/phosphate buffer (pH 7,5), the crude enzyme extract showed maximum protease activity at pH 1,5 ,and optimal temperature at 50°C. After the partially purification of enzyme and analyses of RP-HPLC and SDS-PAGE results it appeared that Nigella sativa seeds protease degrade Triticum aestivum gliadin more efficiently than Triticum durum gliadin after 24h of incubation. The activity of Nigella sativa seeds protease with gliadin as substrate, in pH 7,5 at 37°C after 2h of incubation, before and after partial enzymatic purification prove that the crude enzyme extract have a low activity with Triticum durum gliadin however it was important with Triticum aestivum gliadin, this protease activity was increased in the same conditions using partially purified enzyme and it persist always higer with Triticum durum gliadin comparing with Triticum aestivum gliadin. On the bases of these results, Nigella sativa seeds protease represent the alternative means of treating celiac disease in the future using the detoxification of gliadin to eliminate the immunogenicity of gluten.

Keywords: Gliadin, Celiac disease, Nigella sativa, Protease.