Citation: Fratelli, C.; Bürck, M.; Silva-Neto, A.F.; Oyama, L.M.; De Rosso, V.V.; Braga, A.R.C. Green Extraction Process of Food Grade C-phycocyanin: Biological Effects and Metabolic Study in Mice. Processes 2022, 10, 1793. https:// doi.org/10.3390/pr10091793 Academic Editor: Chi-Fai Chau Received: 12 August 2022 Accepted: 4 September 2022 Published: 6 September 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). processes Article Green Extraction Process of Food Grade C-phycocyanin: Biological Effects and Metabolic Study in Mice Camilly Fratelli 1,2 , Monize Bürck 1,2 , Artur Francisco Silva-Neto 2 , Lila Missae Oyama 2 , Veridiana Vera De Rosso 2,3, * and Anna Rafaela Cavalcante Braga 1,2,4, * 1 Department of Biosciences, Universidade Federal de São Paulo (UNIFESP), Silva Jardim Street, 136, Vila Mathias, Santos 11015-020, Brazil 2 Department of Physiology, Universidade Federal de São Paulo (UNIFESP), Botucatu Street, 740, Vila Clementino, São Paulo 04023-062, Brazil 3 Nutrition and Food Service Research Center, Universidade Federal de São Paulo (UNIFESP), Rua Silva Jardim 136 CEP Santos, São Paulo 11015-020, Brazil 4 Department of Chemical Engineering, Universidade Federal de São Paulo (UNIFESP), Campus Diadema, Diadema, São Paulo 09972-270, Brazil * Correspondence: veridiana.rosso@unifesp.br (V.V.D.R.); anna.braga@unifesp.br (A.R.C.B.) Abstract: This study aimed to evaluate different parameters in the green process of organic Spirulina biomass (SB) C-phycocyanin (C-PC) extraction to understand the impact on weight and oral glucose tolerance of C-PC extract in Swiss mice fed with a high-fat diet (HFD). The proximate composition and antioxidant activity were analyzed in Spirulina by-products: SB, C-PC, and Remaining biomass (RB). The protein content on a dry basis was 52.05% in SB and 61.16% in RB and 118.97 μg/g in C-PC. The antioxidant activity was equal for SB and C-PC but higher than RB. However, RB can be considered a promising ingredient, promoting the sustainable use of the whole SB. Swiss mice were distributed in five groups: control diet (CD), HFD, HFD plus Spirulina biomass (HFDS), HFD plus C-PC (HFDC), and HFD plus remaining biomass (HFDR). HFDS increased the delta weight of the animals and showed glucose intolerance compared to the CD and HFDC groups. The results demonstrated that the supplementation of 500 mg/kg of body weight of SB in the HFDS group did not show antiobesogenic potential with an HFD, but it is essential to conduct further studies to bring other interesting responses regarding C-PC biological in vivo effects. Keywords: green chemistry; antioxidant activity; oral glucose tolerance test—OGTT 1. Introduction The downstream process of intracellular bioproducts from Arthrospira platensis, also known as Spirulina, such as the phycobiliprotein C-PC, comprises several steps, including separation of the cells from the cultivation media, cell rupture, extraction method, pu- rification steps, and refining of the product [1]. Extraction using inorganic solvents has been discussed in several studies as an efficient and alternative method for C-PC recovery. However, recently, efforts have been made to develop more sustainable processes to extract bioactive compounds, including low energy consumption and avoiding the employment of toxic chemicals [2], characteristics capable of triggering both health and environmental problems [3]. As a result, green chemistry procedures are essential in the lab and industry. A recent study intended to enhance extraction and purification of C-PC with lower energy consumption [4] used a shaker, centrifugation, and ultrasonication employing potassium phosphate buffer and obtained less purity ratio than another study [5] that used distilled water as a solvent and kept the Spirulina biomass without agitation (0.34 versus 0.60 purity), showing that simple methods are even greener and suitable for significant scaling up. Sub- sequent purification steps applying ammonium sulfate ((NH 4 ) 2 SO 4 ) and dialysis provide greater purity (1.6) [1]. Processes 2022, 10, 1793. https://doi.org/10.3390/pr10091793 https://www.mdpi.com/journal/processes