Screening biológico de extrato de brócolis (Brassica oleracea L. var. Italica) não encapsulado e encapsulado por electrospraying

Abstract

Chronic non-communicable diseases are a serious public health problem, due to the high degree of morbidity and mortality, especially type II diabetes mellitus, cancers, and neuroinflammatory diseases. Thus, there is a need to develop natural alternatives for the prevention and control of these diseases. Broccoli has glucosinolate and phenolic compounds in its composition, which have several biological effects, such as antioxidant, antimicrobial, antihyperglycemic, and antitumor action. Despite their benefits, these compounds are very unstable at elevated temperatures and pH changes, so there is a need for encapsulation in order to improve their bioavailability. Thus, the objective of the work was to encapsulate broccoli extract by electrospinning/electrospraying techniques and to perform a biological screening of the unencapsulated extract and the encapsulated extract by electrospraying. The capsule produced by electrospraying that showed the best characteristics was evaluated for its antioxidant, antimicrobial, antihyperglycemic, antitumor activity against glial tumor, and neuroprotective activity in vitro. The encapsulated and non-encapsulated extracts were subjected to digestion simulation and evaluated for antioxidant and antihyperglycemic profile. The broccoli extract presented glucosinolates and phenolic compounds in its composition. The electrospinning technique produced fibers and the electrospraying technique produced capsules with smooth morphology, high encapsulation efficiency, and good thermal stability. The capsule with the addition of 50% of extract in relation to zein presented the best characteristics and was chosen for the evaluation of biological activities. The encapsulated and unencapsulated broccoli extract showed antioxidant activity against DPPH and hydroxyl radicals, with no activity detected against the nitric oxide radical. The broccoli extract showed an inhibition halo against S. aureus, E. coli, and S. Typhimurium, and the absence of inhibition of L. monocytogenes, the tested concentrations were not bactericidal. The encapsulated and unencapsulated extracts showed high inhibition of the α-amylase enzyme and moderate inhibition of αglucosidase. The simulation of digestion demonstrated that the compounds are degraded and their concentration is reduced throughout the digestive process, which significantly impacted their antioxidant and antihyperglycemic activity. The extract and the capsule had an antitumor effect against the glioma cell line, showing no toxicity in primary astrocyte culture, in addition, they had a neuroprotective effect in astrocytes exposed to lipopolysaccharide, acting on the reduction of reactive oxygen species and preserving the activity of enzymes antioxidants. The electrospinning/electrospraying technique was efficient for protecting the compounds present in the broccoli extract. The encapsulated and unencapsulated extracts showed antioxidant, antihyperglycemic, antitumor, and neuroprotective effects, and can act in the control of chronic noncommunicable diseases.