Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder

Abstract

This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.Keywords: Arrhenius, stability, kinetic, degradation, cyanobacteria, microalgal biomass. Estabilidade térmica e fotoestabilidade do potencial antioxidante deSpirulina platensis em pó ResumoEste trabalho objetivou avaliar a estabilidade térmica e a foto-estabilidade do potencial antioxidante (PA) da biomassa da Spirulina platensis. A estabilidade térmica foi avaliada a 25ºC, 40ºC e 50ºC por 60 dias. A foto-estabilidade foi avaliada usando luz UV (15 W, λ = 265 nm) e fluorescente (20 W, 0.16 A, fator de potência FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) por 90 dias em cápsulas, vidro e placas de Petri. O PA da biomassa nessas condições foi determinado em intervalos de tempo (a cada 7 e 30 dias nos estudos de estabilidade térmica e foto-estabilidade, respectivamente), usando a indução da oxidação de um sistema lipídico por calor e aeração. Neste sistema lipídico, a biomassa submetida à degradação foi usada como antioxidante. A cinética da reação foi determinada pelo método de Arrhenius. A degradação térmica seguiu uma cinética de zero ordem, enquanto que a fotodegradação seguiu uma cinética de primeira ordem. O PA diminuiu 50% depois de 50 dias a 25°C. A 40°C e 50°C, o PA diminuiu mais de 50% depois de 35 e 21 dias de exposição, respectivamente. A diminuição do PA da Spirulina foi mais sensível à luz UV e fluorescente. Depois de 30 dias de exposição, o PA diminuiu mais de 50% em todas as condições de armazenamento testadas. O potencial antioxidante da Spirulina platensis é facilmente diminuído quando a biomassa é exposta ao calor e a luz, indicando a necessidade de cuidados durante seu armazen...

Two Classes of Pigments, Carotenoids and C-Phycocyanin, in Spirulina Powder and Their Antioxidant Activities

“…Additional food processing techniques and storage conditions can have a similar effect. The antioxidant potential of A. platensis powder was easily degraded after exposure of the biomass to heat and light [18]. …”

Two Classes of Pigments, Carotenoids and C-Phycocyanin, in Spirulina Powder and Their Antioxidant Activities

“…Additional food processing techniques and storage conditions can have a similar effect. The antioxidant potential of A. platensis powder was easily degraded after exposure of the biomass to heat and light[17].The content of all-trans-β-carotene was highest among the four major carotenoid ingredients of the spirulina powder samples in AP-1, C1, C2 and C5 while that of alltrans-zeaxanthin was highest in the other samples. Spirulina are multicellular and Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 25 July 2018 doi:10.20944/preprints201807.0470.v1…”

Spirulina platensispowder is an applicable feed additive for Chinese horseshoe crabTachypleus tridentatus

“…platensis powder. Increasing the temperature and light irradiation would influence antioxidant capacity, which could explain the variation in the MDA level (Colla et al, 2017). Hence, feeding semi‐artificial feeds within a short time (4 weeks) was assumed to have no significant effect on adult Chinese horseshoe crabs.…”