Assessment of phytochemical components, proximate composition and antioxidant properties of Scenedesmus obliquus, Chlorella vulgaris and Spirulina platensis algae extracts

Abstract

In recent decades, natural antioxidant alternatives have become a trending topic for replacing artificial antioxidants. Microalgae have been reported to display interesting bioactive properties and their antioxidant activity is one of them. This study aims to evaluate the antioxidant capacity, phytochemical constituents and proximate composition of three microalgae Scenedesmus obliquus, Chlorella vulgaris and Spirulina platensis. The performed preliminary phytochemical analysis of the algae extracts revealed that they contain good amounts of bioactive compounds. The results showed that the highest total antioxidant activity found was (3720.67 mgAAE/100g) in Spirulina platensis, followed by Chlorella vulgaris (2794.80 mgAAE/100g). The lowest activity was noticed for Scenedesmus obliquus (1718.53 mgAAE/100g). As for total phenolic content, Spirulina recorded the highest phenolic content (2238.46 mgGAE/Kg.), followed by Chlorella (710.33mg GAE/Kg.), and then Scenedesmus (511.20 mgGAE/Kg). The total flavonoids content of algal extracts expressed as mgQE/Kg varied from (548.66) for Chlorella vulgaris, (142.23) for Spirulina platensis to (66.56) for Scenedesmus obliquus. The proximate analysis results indicated high values of protein for Spirulina platensis (53.30 % dry wt.) whereas the highest fat, ash and moisture percentages were recorded by Scenedesmus obliquus (15.13, 15.07 and 2.57, respectively).

Characterization of alginate extracted from Sargassum latifolium and its use in Chlorella vulgaris growth promotion and riboflavin drug delivery

“…They supposed that ISA might enable plants to catch more light energy for increasing photosynthesis and/or improving chlorophyll and carotenoids contents consequently after foliar application of ISA as documented by El-Chaghaby et al . 63 previous study. Moreover, when sodium alginate oligomers functioned as plant growth enhancers, they might stimulate plant vegetative growth leading to increased plant productivity relative to control 64 .…”

“… 65 reported that external organic carbon source supplementation may affect photosynthesis and respiration. Also, oligomers produced by alginate depolymerization stimulates the growth and promote the germination and shoot elongation in plants 63 . In accordance with our data, plant growth induction was achieved by the use of radiated sodium alginate oligosaccharides.…”

Antibacterial activity of silver nanoparticles biosynthesized using Spirulina platensis microalgae extract against oral pathogens

“…The extract was prepared as previously given by El-Chaghaby et al, (2019). Briefly, Spirulina powder was added to ethanol and the mixture was ultrasonicated for two hours at room temperature.…”

Optimizing the ultrasonic-assisted extraction of antioxidants from Ulva lactuca algal biomass using factorial design

“…Several studies have shown that algal biomass has many phytochemicals and has several bioactivity types [12,13]. Ulva lactuca (sea lettuce) is a widespread macroalga among many seaweeds growing along the Mediterranean coast in Egypt, particularly in Alexandria [14].…”