Optimization of β-Fructofuranosidase Production from Agrowaste by Aspergillus carbonarius and Its Application in the Production of Inverted Sugar
Ryhára Dias Batista1, Fernanda Guimarães Melo1, Claudia Cristina Auler do Amaral Santos1, Fabrício Coutinho de Paula-Elias1, Rafael Firmani Perna2, Michelle Cunha Abreu Xavier3, Sergio Andres Villalba Morales2 and Alex Fernando de Almeida1*
1Graduate Program in Food Science and Technology, Federal University of Tocantins, 109 Norte Av. NS-15, ALCNO-14, Plano Diretor Norte, CEP: 77001-090, Palmas, Tocantins, Brazil
2Federal University of Alfenas (UNIFAL-MG), Institute of Science and Technology, José Aurélio Vilela Road 11999, Km 533, Zip Code 37715-400, Poços de Caldas, MG, Brazil
3Federal University of Tocantins (UFT), Department of Bioprocess Engineering and Biotechnology, Badejos Street 69-72, Jardim Cervilha, Zip Code 77404-970, Gurupi, TO, Brazil
Received: 8 August 2020
Accepted: 14 July 2021
invertase, Aspergillus carbonarius PC-4, culture optimization, simplex lattice design, sucrose hydrolysis
Research background. Microbial β-fructofuranosidases are widely employed in food industry to produce inverted sugar or fructooligosaccharides. In this study, a newly isolated Aspergillus carbonarius PC-4 strain was used to optimize the β-fructofuranosidase production in a cost-effective process and the sucrose hydrolysis was evaluated to produce inverted sugars.
Experimental approach. Optimization of nutritional components of culture medium was carried out using simplex lattice mixture design for 72 and 120 h at 28 °C. One-factor-at-a-time methodology was used to optimize the physicochemical parameters. Crude enzyme was used for sucrose hydrolysis at different concentrations.
Results and conclusions. The optimized conditions of enzyme production were achieved from cultivations containing pineapple crown waste (1.3 %, m/V) and yeast extract (0.3 % m/V) after 72 h with an enzyme activity of 9.4 U/mL, obtaining R²=91.85 %, R²adjusted=85.06 %, highest F-value (13.52) and low p-value (0.003). One-factor-at-a-time used for optimizing the physicochemical conditions showed optimum temperature (20 °C), pH (5.5), agitation (180 rpm) and time course (72 h) with a 3-fold increase of enzyme production. The invertase-induced sucrose hydrolysis showed the maximum yield (3.45 mmol of reducing sugars) using 10 % of initial sucrose concentration. Higher sucrose concentrations caused the inhibition of invertase activity, possibly due to the saturation of substrate or formation of sucrose aggregates, making it difficult for the enzyme to access sucrose molecules within the created clusters. Therefore, a cost-effective method was developed for the invertase production using agroindustrial waste and the produced enzyme can be used efficiently for inverted sugar production at high sucrose concentration.
Novelty and scientific contribution. This study presents an efficient utilization of pineapple crown waste to produce invertase by a newly isolated Aspergillus carbonarius PC-4 strain. This enzyme exhibited a good potential for inverted sugar production at high initial sucrose concentration, which is interesting for industrial applications.