Abstract
Antioxidants from Psidium guajava leaves were extracted with 70% ethanol in water. The extractive solution was concentrated and submitted to spray drying in the presence of technological adjuvants at a proportion of 8 % wet base. Three distinct technological adjuvants were evaluated: β-cyclodextrin (βCD-80), maltodextrin DE10:Aerosil® (MA-80 - 7:1), and maltodextrin DE10:Encapsia®:Aerosil® (MDEA-80 - 5:2:1). The antioxidant activity of the concentrated extract and spray-dried powders was assessed by three antioxidant assays, namely: the2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, ferric reducing antioxidant power (FRAP), and oxygen radical absorption capacity (ORAC). The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging capacity was determined previously. The spray-dried powders exhibited strong antioxidant activity (IC50 value = 7.96 to 9.76 μg/mL – DPPH method; 3,125.1 to 3,406.0 μM TE/g dry weight – ABTS method; 4,210 to 4,540 μM FeSO4 E/g – FRAP method; 1,820-2,020 μM TE/g – ORAC method). The technological adjuvants did not significantly interfere with the antioxidant activity of the dried products, regardless the type of antioxidant assay used. The results here reported strongly evidenced that the concentrated and spray-dried extracts of Psidium guajava are rich sources of natural antioxidants with potential application in food, pharmaceutical, and cosmeceutical products.
Highlights
Psidium guajava Linn. (Myrtaceae) is native from Central and South America and has been cultivated in various tropical and subtropical countries
The antioxidant activity of the concentrated extract and spray-dried powders was assessed by three antioxidant assays, namely: the 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, ferric reducing antioxidant power (FRAP), and oxygen radical absorption capacity (ORAC)
This study reports the antioxidant activity of crude and spray-dried extracts of P. guajava leaves assessed by three distinct in vitro antioxidant methods – 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, ferric reducing antioxidant power (FRAP), and oxygen radical absorption capacity (ORAC) – and compared with the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging activity determined previously (Fernandes et al, 2014b)
Summary
Psidium guajava Linn. (Myrtaceae) is native from Central and South America and has been cultivated in various tropical and subtropical countries. Vol 7, No 4; 2018 heat-sensitive components such as bioactive compounds present in plant extracts, enzymes, and other pharmaceuticals Technological carriers such as gums, semi-synthetic cellulose derivatives, and synthetic polymers are commonly added to the drying mixture to protect these components from degradation, optimize the drying performance, and improve the physicochemical properties of the products (Sollohub & Cal, 2010; Cortés-Rojas & Oliveira, 2012). Hydroalcoholic extracts from P. guajava leaves are rich in phenolic compounds, flavonoids, and tannins (Venkatachalam et al, 2012; Fernandes et al, 2014a) and may probably act as natural antioxidants for food and pharmaceutical products. Analysis of the correlation between the antioxidant capacity and the phenolic and flavonoid content of the crude and dried extracts is presented
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
