Berries for glucose control: New supplement on the cards after Korean researchers record positive RCT results

Berry-extract-and-soybean-mixture-shown-to-improve-hyperglycemia.png
Schisandra chinensis is also known as the five-flavour fruit or Omija in Korean. ©Getty Images

A group of South Korean researchers plan to develop new supplements with functional claims using a mixture containing berry extract and soybean for controlling hyperglycemia, following positive human clinical trial results.

Hyperglycemia is a symptom in patients suffering from type II diabetes and is manifested by the rapid rise in plasma glucose levels. 

The berry in question is schisandra chinensis, also known as Omija in Korean, or five-flavour fruit in layman term. The red-coloured berry is native to Korea, China and has been used as a medicinal plant mostly in East Asia.

In particular, the researchers found that the combination of omija extract and soybean (OSM) could bring about synergistic effects in blood glucose control and the effects are stronger than using omija extract or soybean alone.

“OSM exhibited much better inhibitory effects on α-glucosidase, α-amylase activities, and DPPH scavenging compared with Omija extract or soybean powder,” said the researchers.

Writing in Nutrients, the researchers from the Healthcare Claims & Management Incorporation, Jeonbuk National University, Woosuk University, said that the supplementation of omija extract and soybean has shown to significantly reduce fasting plasma glucose and postprandial glucose.

This was seen from a 12-week randomised, double-blinded, placebo-controlled trial involving 80 participants with fasting plasma concentrations between 100mg/dL and 140mg/dL.

The trial was conducted between February and October 2021 at the Woosuk University Korean Medicine Hospital and supported by the Ministry of Agriculture, Food, and Rural Affairs (MAFRA).

Prior to the trial, the researchers have confirmed the synergic effects of Omija extract and soybean mixture on fasting and post-glucose and insulin levels, as well as insulin resistance in both in vitro and in vivo settings.

During the trial, the intervention group was instructed to take two capsules twice per day – after breakfast and dinner, taking two capsules each time. Each capsule contains 125mg of OSM.

In the clinical trial, it was expected that OSM would lower the blood glucose level and reduce insulin secretion.  

Findings

Significant reduction in fasting plasma glucose and postprandial glucose were observed in the intervention group following the trial.

For instance, the intervention group saw its fasting plasma glucose reduced to 111.00 ± 12.07 mg/dL, a significant reduction of 5.62 ± 9.73mg/dL from baseline. The placebo group, however, saw a slight increase of 0.66 ± 12.25 mg/dL by the end of the study.

Postprandial glucose at the 60th minute after a meal had also dropped significantly from 213.62 ± 45.15 mg/dL to 202.15 ± 51.56 mg/dL in the intervention group by the end of the study.

For the placebo group, their postprandial glucose at the 60th minute had increased from 186.76 ± 40.25 mg/dL to 201.14 ± 40.45 mg/dL instead.

Other parameters, such as postprandial insulin, insulin area under the curve, and the amount of fructosamine had also decreased in the intervention group.

Fructosamine is a compound that is formed when glucose combines with a blood protein and has a half-life of approximately 20 days.

As such, measuring its concentration could reflect the recent two to three weeks changes in blood glucose levels, said the researchers.

In the case of the intervention group, fructosamine levels had dropped significantly from 262.88 ± 24.46 μmol/L to 254.97 ± 20.90 μmol/L.

 

Source: Nutrients

Efficacy and Safety of Omija (Schisandra chinensis) Extract Mixture on the Improvement of Hyperglycemia: A Randomized, Double-Blind, and Placebo-Controlled Clinical Trial

https://doi.org/10.3390/nu14153159

Authors: Kim, D.-S et al