Research on the green extraction process and high-value application of amino acids based on synthetic biology in tea dry cakes

Abstract

As the main by-product of tea seed oil extraction, tea dry cake is rich in amino acid resources, but its complex cellulose-lignin structure limits the efficient release of amino acids. In this study, an engineered strain of Corynebacterium glutamicum was constructed based on synthetic biology techniques Combined with the high-efficiency amino acid circulation extraction device (patent number: CN202310001234), the efficient extraction of free amino acids is realized. CRISPR/Cas9 gene editing enhanced the expression of cellulase (cel7A) and lignin peroxidase (lipH8), and the enzyme activity was increased to 125 U/mL and 98 U/mL, respectively. Combined with dynamic nozzle positioning (accuracy ±1 mm), multi-stage filtration (0.45μm filter element) and fin heat dissipation system (temperature control ≤35°C), the total extraction rate of amino acids reached 85.7%, and the purity was 95.3%, which was 52% more efficient than the traditional extraction method. The cleaning rate of the extracted amino acid compound detergent is 85% at 25°C, which is 23% higher than that of traditional APG. This study provides a green and efficient industrialization solution for the recycling of tea dry cakes.