Toxicological and bioactivity evaluation of blackcurrant press cake, sea buckthorn leaves and bark from Scots pine and Norway spruce extracts under a green integrated approach

Nora Pap,Dhanik Reshamwala,Risto Korpinen,Petri Kilpeläinen,Marina Fidelis,Marianna M Furtado,Anderson S Sant’Ana,Mingchun Wen,Liang Zhang,Jarkko Hellström,Pertti Marnilla,Pirjo Mattila,Tytti Sarjala,Baoru Yang,Amanda Dos Santos Lima,Luciana Azevedo,Varpu Marjomäki,Daniel Granato

doi:10.1016/j.fct.2021.112284

Abstract

Aqueous extracts from blackcurrant press cake (BC), Norway spruce bark (NS), Scots pine bark (SP), and sea buckthorn leaves (SB) were obtained using maceration and pressurized hot water and tested for their bioactivities. Maceration provided the extraction of higher dry matter contents, including total phenolics (TPC), anthocyanins, and condensed tannins, which also impacted higher antioxidant activity. NS and SB extracts presented the highest mean values of TPC and antioxidant activity. Individually, NS extract presented high contents of proanthocyanidins, resveratrol, and some phenolic acids. In contrast, SB contained a high concentration of ellagitannins, ellagic acid, and quercetin, explaining the antioxidant activity and antibacterial effects. SP and BC extracts had the lowest TPC and antioxidant activity. However, BC had strong antiviral efficacy, whereas SP can be considered a potential ingredient to inhibit α-amylase. Except for BC, the other extracts decreased reactive oxygen species (ROS) generation in HCT8 and A549 cells. Extracts did not inhibit the production of TNF-alpha in lipopolysaccharide-stimulated THP-1 macrophages but inhibited the ROS generation during the THP-1 cell respiratory burst. The recovery of antioxidant compounds from these by-products is incentivized for high value-added applications.

Highlights

Side streams of berries and woods offer diverse sources of various bioactive compounds
A study concerning the effects of different pre-treatment maceration techniques on the content of phenolic compounds, antioxidant capacity, and other chemical properties reported that this procedure improved the extraction of compounds from red grape skin (Wojdyło et al, 2021)
Ma et al (2019) found that ellagitannins were the main responsible for the antioxidant activity of sea buckthorn leaves (SB) leaves aqueous extract measured by the 2-deoxyribose assay and metal chelating ability

Summary

Introduction

Side streams of berries and woods offer diverse sources of various bioactive compounds. Industrial side streams from berry and wood sectors have a huge potential as they may contribute to the improvement of the circular economy, especially if cascade use models are adopted, that is, reusing and recycling products as many times as possible before their final disposal via energy gener ation or landfilling. In this panorama, in many EU countries, the pro duction of sea buckthorn (SB), Norway spruce (NS), Scots pine (SP), and blackcurrant (BC) is of economic significance as a wide array of products are manufactured – from food ingredients to furniture. According to Tian et al (2017), the sea buckthorn leaves contained more polyphenols and showed different phenolic profiles (ellagitannins above 90%) from the corresponding berries

Objectives

Methods

Results