Due to the scarcity of sustainable inputs for photosynthetic microorganisms’ biotechnology, the search for natural substrates such as coconut water has gained prominence. This by-product is a substrate rich in macro- and micronutrients, as well as endogenous phytohormones that support microbial growth. In this context, this study aimed to use it as an alternative cultivation medium for Limnospira platensis (Gomont), formerly known as Arthrospira platensis, a high-value cyanobacterium. We evaluated growth parameters, phycocyanin concentration, purity, and biomass yield cultivated in coconut water and in SAG_1x medium, a modified Zarrouk medium. Over 35 days of cultivation, both media efficiently supported cyanobacterial growth. In coconut water, the specific growth rate was 0.305 d⁻¹, the maximum growth rate was 0.629 d⁻¹, and the productivity was 0.256 g L⁻¹ d⁻¹. In SAG_1x medium, the values obtained were 0.240 d⁻¹, 0.676 d⁻¹, and 0.218 g L⁻¹ d⁻¹, respectively. Phycocyanin obtained from cultivation in SAG_1x medium presented food-grade purity (OD620/OD280 ratio > 0.7), while in coconut water, it was 0.6. The pigment concentration and yield in SAG_1x (19.1 mg/L and 34.3%, respectively) also slightly exceeded those obtained with coconut water (14.3 mg/L and 25.5%, respectively). Despite this, the data reinforce the potential of coconut water as a viable and economically competitive alternative to conventional media for L. platensis production.

This study assessed the effects of dietary shrimp head meal (SHM) on growth performance, metabolism, antioxidant status, and health of Nile tilapia ( Oreochromis niloticus ) fingerlings. Five isonitrogenous and isoenergetic diets were precisely formulated on a digestible nutrient basis, containing graded SHM levels (0, 5, 10, 15, and 20%), and fed for 45 days to fish (3.24 ± 0.07 g) reared in 50 L tanks (10 fish tank ⁻¹ ; four replicates diet ⁻¹ ) within a recirculating aquaculture system. Growth performance increased significantly with SHM inclusion, and quadratic regression analyses suggested an estimated inclusion level near 16% associated with maximal weight gain and feed conversion efficiency. Improved eviscerated weight and whole-body protein, together with reduced hepatosomatic and viscerosomatic indexes and lipid content, indicated a shift toward lean growth and efficient nutrient utilization. Enhanced villus height and elevated digestive enzyme activities (amylase, proteases, and lipases) confirmed superior nutrient assimilation. Antioxidant defenses were strengthened by higher catalase and glutathione activities in liver and muscle, while feed malondialdehyde content decreased with increasing SHM levels during storage. Hematological and biochemical improvements, including higher erythrocyte, leukocyte, and platelet counts, elevated serum protein fractions, and lower glucose, cholesterol, alanine aminotransferase, and aspartate aminotransferase levels, reflected enhanced metabolic regulation, immune competence, and hepatoprotection. Collectively, these results demonstrate that SHM functions not only as a sustainable protein source but also as a functional feed ingredient that enhances physiological resilience. The valorization of shrimp-processing residues through SHM inclusion supports circular bioeconomic development and sustainable intensification in aquaculture.

Anais do Congresso Internacional em Saúde e Desenvolvimento Socioambiental (978-65-272-0801-3) - Análise Epidemiológica Temporal Das Notificações De Hiv/Aids No Município De Recife No Período De 2019 A 2023