An insight into Cochlospermum planchonii extracts obtained by traditional and green extraction methods: Relation between chemical compositions and biological properties by multivariate analysis

In African traditional medicine Cochlospermum planchonii is used to manage various diseases such as malaria, diarrhoea, jaundice, infections and inflammation, hence presents the potential to be a good source of bioactive compounds. In this study, traditional and green extraction techniques have been used namely green extraction (homogenizer assisted extraction (HAE) and Sonication (SON)) and conventional extraction (Maceration (MAC), and Soxhlet (SOX)). Extracts prepared from aerial parts were studied for the total phenolic, flavonoids, total antioxidant and enzyme inhibitory properties also relating their biological properties and chemical content by multivariate analysis. The total phenolic contents obtained were in the order of HAE (221.78 mg gallic acid equivalent (GAE)/g) > SON (202.64 mg GAE/g) > SOX (190.28 mg GAE/g) > MAC (187.45 mg GAE/g). The highest flavonoid content (rutin equivalent (RE)) was obtained by SOX (65.67 ± 0.43 mg rutin equivalent (RE)/g). The highest antioxidant activity was recorded for HAE. C. planchonii extracts showed inhibitory activity against acetylcholinesterase (8.46–8.56 mg galantamine equivalent (GALAE)/g), tyrosinase (165.76–171.10 mg kojic acid equivalent (KAE)/g) and α-amylase (1.18–1.30 mmol acarbose equivalent (ACAE)/g) enzymes. It was found that the observed enzyme inhibitory properties was dependent on the type of extraction methods. Only SOX extract presented α-glucosidase inhibition (21.26 mmol ACAE/g) suggesting potential studies of this extract as antidiabetic. Liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry (LC-DAD-ESI-MSn) was used for the qualitative analysis of the samples, allowing the quantification of gallic acid, prodelphynidins and flavonol derivatives. Based on multivariate analysis, green extraction techniques (HAE and SON) were different from conventional techniques (MAC and SOX). Results showed the usefulness of green extraction techniques for obtaining bioactive enriched fractions and tend to highlight the need for additional investigations to fully explore the potential usefulness of C. planchonii as source of antioxidant, antidiabetic and whitening agent as well as cholinesterase inhibitors.