Evaluation of the antioxidant profile and cytotoxic activity of red propolis extracts from different regions of northeastern Brazil obtained by conventional and ultrasound-assisted extraction

Abstract

Propolis is a complex mixture of resinous and balsamic material collected from the exudates of plants, shoots, and leaves by bees. This study evaluated red propolis extracts obtained by conventional (ethanolic) extraction and ultrasound-assisted extraction of six samples from different regions of northeastern Brazil. The total phenolic compounds and flavonoids, in vitro antioxidant activity, concentration of formononetin and kaempferol and the cytotoxicity against four human tumor cell lines were determined for all twelve obtained extracts. Significant variations in the levels of the investigated compounds were identified in the red propolis extracts, confirming that the chemical composition varied according to the sampling region. The extraction method used also influenced the resulting propolis compounds. The highest concentration of the compounds of interest and the highest in vitro antioxidant activity were exhibited by the extracts obtained from samples from state of Alagoas. Formononetin and kaempferol were identified in all samples. The highest formononetin concentrations were identified in extracts obtained by ultrasound, thus indicating a greater selectivity for the extraction of this compound by this method. Regarding cytotoxic activity, for the HCT-116 line, all of the extracts showed an inhibition of greater than 90%, whereas for the HL-60 and PC3 lines, the minimum identified was 80%. In general, there was no significant difference (p>0.05) in the antiproliferative potential when comparing the extraction methods. The results showed that the composition of Brazilian red propolis varies significantly depending on the geographical origin and that the method used influences the resulting compounds that are present in propolis. However, regardless of the geographical origin and the extraction method used, all the red propolis samples studied presented great biological potential and high antioxidant activity. Furthermore, the ultrasound-assisted method can be efficiently applied to obtain extracts of red propolis more quickly and with high concentration of biomarkers of interest.

Biomedical Properties of Propolis on Diverse Chronic Diseases and Its Potential Applications and Health Benefits

“…Similarly, the chemical composition of Mexican propolis has been studied by various research groups, identifying compounds such as rutin, naringenin, hesperetin, pinocembrin, caffeic acid phenethyl ester (CAPE), chrysin, naringin, kaempferol, quercetin, acacetin, luteolin, pinostrobin, izalpinin, rhamnetin, galangin, alpinetin, dillenetin, cinnamic acid, caffeic acid, ferulic acid, and syringic acid, and reporting differences in the content of compounds depending on the geographical area [ 28 , 29 , 30 , 31 ]. In Brazil, the composition of red, green, and brown propolis has been described, and different compounds have been reported, such as caffeic acid, gallic acid, transferulic acid, p -coumaric acid, catechin, epicatechin, kaempferol, formononetin, quercetin, rutin hydrate, luteolin, artepillin C, and CAPE [ 32 , 33 , 34 , 35 ]. As mentioned above, the geographical location directly determines the chemical composition of propolis; hence, in a study carried out with different samples of propolis from southern Brazil, three phenolic acids (gallic acid, caffeic acid, and coumaric acid), a prenylated derivative of cinnamic acid (artepillin C), and a flavonoid (pinocembrin) were identified [ 36 ].…”

Chinese Propolis: Ultrasound‐assisted enhanced ethanolic extraction, volatile components analysis, antioxidant and antibacterial activity comparison

“…Propolis is a material collected by bees from the sap of trees and mixed with their saliva to seal and sterilize the hive (Reis et al., 2019). Generally, propolis is composed of 50% resins, 30% vegetable balsams, 10% wax, 5% aromatic and essential oils, and 5% pollens and other substances (Rufatto et al., 2017).…”

Metal Content of Nutritional and Toxic Value in Different Types of Brazilian Propolis

“…Propolis (bee glue) is a generic name for the resinous substance collected by honey bees (Apis mellifera) from various plant sources (substances exuded from wounds in plants, lipophilic materials on leaves and leaf buds, gums, resins, and lattices) and mixing salivary enzymes (β-glucosidase) that it is used to seal holes in the honeycombs and smooth out the internal walls [1,2]. More than 420 different compounds have been characterized so far in propolis, giving it diverse pharmacological properties such as antimicrobial, antioxidative, anticancer, anti-inflammatory, antifungal, antiparasitic, and antiviral activities [2,3].…”