Functional Properties and Antioxidant Activity of <i>Morus alba</i> L. Leaves var. Zolwinska Wielkolistna (WML-P)-The Effect of Controlled Conditioning Process

• Main Authors: Monika Przeor (Author), Ewa Flaczyk (Author), Dominik Kmiecik (Author), Maciej S. Buchowski (Author), Halina Staniek (Author), Aneta Tomczak-Graczyk (Author), Joanna Kobus-Cisowska (Author), Anna Gramza-Michałowska (Author), Joanna Foksowicz-Flaczyk (Author)
• Format: Book
• Published: MDPI AG, 2020-07-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

This study evaluated the effect of adding a new step, termed conditioning, to the traditional processing of leaves from <i>Morus alba</i> var. zolwinska wielkolistna grown in Poland (WML-P). This step, modeled on tea leaves processing, was conducted in a controlled environment on a semi-technical scale. The primary goal was to evaluate the effect of the WML-P conditioning for 1-4 h at 32-35 °C on the content of bioactive compounds (total phenolics, phenolic acids, flavonols, 1-deoxynojirimycin) and antioxidant activity (radical scavenging against DPPH, antioxidant capacity, chelating activity and ferric reducing antioxidant potential) of the lyophilized extracts. For the first time WML-P extracts content was comprehensively characterized by assessing dietary fiber fractions, fatty acids, amino acids, macro- and microelements and chlorophyll content. Compared to the traditional process, adding the conditioning step to WML-P processing resulted in an increased total phenolics content, radical scavenging capacity, ability to quench 2,2-diphenyl-1-picrylhydrazyl (DPPH^•) and iron-chelating ability in the lyophilized extracts. The beneficial effect depended on conditioning time. The highest flavonols and phenolic acids content were found after 2-h conditioning. We concluded that adding a 2-h conditioning step to traditional WML-P processing results in getting WML-P lyophilized extract with increased bioactive compounds content and high antioxidant activity.

Item Description

10.3390/antiox9080668
2076-3921