Haskap Berry Leaves (Lonicera caerulea L.)—The Favorable Potential of Medical Use

Abstract

The presented research evaluates the medical use potential of Lonicera caerulea leaves, which are waste plants in cultivating berries. The study’s screening activity included the leaves of five varieties of Lonicera caerulea: Atut, Duet, Wojtek, Zojka, and Jugana. The microbiological analysis confirmed the safety of using Lonicera caerulea leaves without significant stabilization. Lonicera caerulea leaves standardization was carried out based on the results of the chromatographic analysis, and it showed differences in the contents of active compounds (loganic, chlorogenic and caffeic acids, and rutin), which are attributed to biological activity. For the Lonicera caerulea leaves varieties tested, the differences in the content of total polyphenol content, chlorophylls, and carotenoids were also confirmed. The screening of biological activity of five Lonicera caerulea leaf varieties was carried out concerning the possibility of inhibiting the activity of α-glucosidase, lipase, and hyaluronidase as well, and the antioxidant potential was determined. The defined profile of the biological activity of Lonicera caerulea leaves makes it possible to indicate this raw material as an essential material supporting the prevention and treatment of type II diabetes. However, this research showed that tested enzymes were strongly inhibited by the variety Jugana. The health-promoting potential of Lonicera caerulea leaves was correlated with the highest chlorogenic acid and rutin content in the variety Jugana.

Health Benefits of Antioxidant Bioactive Compounds in the Fruits and Leaves of Lonicera caerulea L. and Aronia melanocarpa (Michx.) Elliot

“…Many studies have indicated the beneficial effects of L. caerulea fruits in supporting the treatment of obesity and diabetes [83]. A Korean study coordinated by Chun et al (2018) investigated the influence of L. caerulea fruit extract ingestion on mildly diabetic obese mice fed a high-fat diet.…”

“…The leaves of haskap were recently found to be an important source of bioactive compounds. According to the variety, the total phenolic content varied between 32.127 and 52.399 mg/g, carotenoids content was between 1.848–2.876 mg/g, while chlorophyll A and chlorophyll B were present in concentrations of 10.642–14.003 and 4.463–5.575 mg/g, before storage [ 83 ]. The leaf extract prepared by ultrasonication in distilled water at 30 °C for 60 min contained several phenolic acids, such as loganic acid with anti-inflammatory properties acting against hyaluronidase and hypolipidemic potential acting against lipase, chlorogenic acid with antidiabetic potential acting against α-glucosidase, and caffeic acid with antioxidant and anti-inflammatory activity [ 83 ].…”

“…According to the variety, the total phenolic content varied between 32.127 and 52.399 mg/g, carotenoids content was between 1.848–2.876 mg/g, while chlorophyll A and chlorophyll B were present in concentrations of 10.642–14.003 and 4.463–5.575 mg/g, before storage [ 83 ]. The leaf extract prepared by ultrasonication in distilled water at 30 °C for 60 min contained several phenolic acids, such as loganic acid with anti-inflammatory properties acting against hyaluronidase and hypolipidemic potential acting against lipase, chlorogenic acid with antidiabetic potential acting against α-glucosidase, and caffeic acid with antioxidant and anti-inflammatory activity [ 83 ]. An extract prepared by aqueous two-phase flotation using ammonium sulfate-ethanol presented increased yields of flavonoids, such as rutin, luteolin-7-O-glucoside, and diosmin, which provided increased antioxidant capacity [ 84 , 85 ].…”

“…Another study showed that the administration of an L. caerulea leaf infusion lowered the cholesterol level and inhibited the enzymes responsible for the absorption of simple sugars, which indicated the potential beneficial effects of haskap leaves in type 2 diabetes [ 83 ].…”

Exploring Beneficial Properties of Haskap Berry Leaf Compounds for Gut Health Enhancement

“…The pivotal preliminary study identified the most active variety of haskap berry leaves, showcasing high antioxidant potential and significant inhibitory activity against α-glucosidase, hyaluronidase, and lipase. Recognising the potential relevance of these findings in diabetes, our study builds upon this foundation to explore the application of haskap berry leaves in addressing aspects of this metabolic condition [ 9 ].…”