E-rutin is a derivative of quercetin to which glucose has been added to improve water solubility and absorption (see structure). Quercetin is a polyphenol and is classified as a flavonoid and is found in apples, onions, grapes, and broccoli. Although quercetin and rutin have been reported to have antioxidant functions and useful functions for muscle and exercise, they are not absorbed into the body from the digestive tract very efficiently.
On the other hand, E-rutin, one of the derivative of quercetin is highly water soluble and has more dramatically improved absorption, with a bioavailability that is 17 times greater than quercetin and 43 times greater than rutin. Furthermore, E-rutin has received GRAS (Generally Recognized As Safe) certification by the Food and Drug Administration (FDA) as a safe food, and is also recognized as a food additive in Japan.
Morinaga's E-rutin is made from enzymatically processed rutin derived from Japanese pagoda tree Styphnolobium japonicum (pictured), and does not contain buckwheat-derived ingredients.
Thirty-nine male college students on the American football team intook whey protein containing 42mg of rutin six times a week for four months, and their body weight, body composition, and oxidative stress level (BAP/d-ROMs ratio) were measured.
We carried out this test, in the American football game season when the subjects lose weight even though they eat a good diet due to strenuous exercise.
The results showed that the E-rutin group significantly increased muscle weight and lean body mass in the lower extremities, as well as potential antioxidant ability in the blood, compared to the placebo group taking E-rutin-free whey protein. In muscle mass, the E-rutin also increased more significantly than before intake.
These results indicate that intake of E-rutin with protein reduces oxidative stress and increases muscle mass.
O. Naomi et. al., J. Int. Soc. of Sports Nutr. 45, 16 (2019)
Nine healthy adult males took supplements containing E-rutin twice a day for seven days before the test and before muscle training on the day of the test, and whey protein containing E-rutin after muscle training (resistance exercise). And then, the concentration of insulin and free testosterone in serum were measured.
The results showed that serum insulin concentration, free testosterone concentration, in area under the concentration curve (AUC) for 40 minutes after resistance exercise were significantly increased in the E-rutin group compared to the placebo group. On the other hand, there was no difference in the speed of muscular power recovery after exercise.
These results indicate that intake of E-rutin with protein increases the response of anabolic hormones (insulin and free testosterone) associated with resistance exercise.
K. Goto et. al,. The 19th Annual Meeting of Japan Society of Exercise and Sports Physiology (2011)
Seventeen athletes using Morinaga's Training Lab were asked to consume E-rutin protein for approximately one month, and their weight and body fat percentage were measured and questioned.
The results showed that although there was no significant difference in body weight, there was a significant increase in lean body mass after intake of E-rutin. The results of the questionnaire also showed that many athletes could feel the benefits of E-rutin.
A. Kohara et. al., Food Style 21, 15, 48 (2011)
Reactive oxygen species generated during exercise can damage muscle cells and tissues, but E-rutin, with its high antioxidant activity, is thought to protect cells and tissues by inhibiting or eliminating the generation of reactive oxygen species, thereby protecting of muscles. Therefore, the antioxidant effects of E-rutin on muscle were examined at the in vivo level.
Male BALB/c mice were divided into two groups: control diet and E-rutin 0.2% diet, and they were subjected to the endurance swimming training (for maximum time at a flow rate of 13L/min) once a week for ten weeks.
As a result, the gastrocnemius muscle weight was significantly increased in the E-rutin group compared to the control diet (E-rutin-free diet) groupalthoughhere was no significant change in body weight in both groups. In addition, blood oxidative stress markers were significantly suppressed and potential antioxidant capacity was enhanced in the E-rutin group compared to the control diet group. In addition, there was no significant change in BAP levels in both groups.
These results suggest that intake of E-rutin during exercise suppresses oxidative stress during exercise and contributes to muscle weight gain.
R. Itoh, et. al., Jpn. J. Exercise Sports Physiol, 27(2), 27 (2020)
The effects of E-rutin intake on muscle hypertrophy in animals were examined in two in vivo studies.
〈in vivo 1〉 Male ICR mice were divided into 4 groups, which were fed either a normal diet or a diet containing 0.03% E-rutin, and each group was also given functional overloaded treatment or a sham treatment, and their plantaris muscle cross-sectional area was measured after 3 weeks of treatment.
The results showed that the transverse area of plantaris muscle fibers was significantly larger in the E-rutin group than in the control group fed an E-rutin-free diet. In addition, the transverse area of muscle fibers in the E-rutin group was larger with muscle loading.
〈in vivo 2〉 Male ICR mice were divided into three groups: a test diet in which the protein in the standard diet was replaced with whey protein, or a test diet plus 0.003% or 0.03% E-rutin and 3 weeks after of muscle exercise treatment, the muscle fiber cross-sectional area of plantaris muscle was measured.
The results showed that the E-rutin group increased the cross-sectional area of muscle fibers in a concentration-dependent manner compared to the control group.
These results indicate that E-rutin intake may have the ability to increase muscle hypertrophy without training. Furthermore, it was shown that E-rutin enhanced the muscle hypertrophy function in a dose-dependent manner, and it was also enhanced when E-rutin was taken at the same time as whey protein.
A. Kohara et. al., J. Int. Soc. Sports Nutr. 32, 14 (2017)
The effects on protein (amino acid) digestion and absorption were examined in 10 healthy male university students who consumed E-rutin and whey protein at the same time.
The results showed that the concentrations of total amino acids (TAA), essential amino acids (EAA), and branched-chain amino acids (BCAA) in the blood of the E-rutin + whey protein group tended to be significantly increased or increased after 60 minutes of intake compared to the whey protein group. Among the individual amino acids, the blood levels of cysteine, tyrosine, histidine, and methionine tended to be significantly elevated or increased in the E-rutin + whey protein group at 45 or 60 minutes after intake. Although some amino acids remained unchanged in the E-rutin + whey protein group, no amino acids showed a decrease in blood concentrations, and no absorption inhibition by E-rutin was observed.
In summary, intake of E-rutin with protein increased the blood amino acid concentration of the amino acid as a whole. In other words, E-rutin may have a function to promote protein absorption.
N. Omi et. al., Jpn Pharmacology and Therapy, 48, 51 (2020)