Risk Assessment of "Other Substances" – D-Ribose

The Norwegian Scientific Committee for Food Safety (NFSA) [Vitenskapskomiteen (VKM) for mattrygghet] has, at the request of the Norwegian Food Safety Authority (Mattilsynet; NFSA), assessed the risk of "other substances" in food supplements and energy drinks sold in Norway. VKM has assessed the risk of doses in food supplements and concentrations in energy drinks given by NFSA. These risk assessments will provide NFSA with the scientific basis while regulating the addition of “other substances” to food supplements and other foods. "Other substances" are described in the food supplement directive 2002/46/EC as substances other than vitamins or minerals that have a nutritional and/or physiological effect. It is added mainly to food supplements, but also to energy drinks and other foods. VKM has not in this series of risk assessments of "other substances" evaluated any claimed beneficial effects from these substances, only possible adverse effects. The present report is a risk assessment of D-ribose, and it is based on previous risk assessments and articles retrieved from a literature search. According to information from NFSA, D-ribose is an ingredient in food supplements sold in Norway. NFSA has requested a risk assessment of 3100 and 6200 mg/day of D-ribose in food supplements for the age groups children (10 to <14 years), adolescents (14 to <18 years) and adults (>18 years). Other sources of D-ribose, such as foods and cosmetics, have not been included in the present risk assessment. D-ribose is a component of the genetic material RNA and is synthesized in all living cells via the pentose phosphate pathway. D-ribose is also a structural component of adenosine triphosphate (ATP), the primary source of cellular energy and a key component of riboflavin (e.g. vitamin B2). The estimated endogen synthesis of D-ribose is referred to be from 2.7 g per day (women) to 16.5 g per day (men). D-ribose is available in small amounts in the diet via ripe fruits and vegetables. It is also an ingredient in food supplements, some so-called energy drinks and in cosmetics as skin conditioner and humectant. Orally administered D-ribose is absorbed in the small intestine by passive diffusion. Absorption rates after oral ingestion of doses up to 200 mg/kg bw per hour (administered for 5 hours) has been shown to range from 87.8 to 99.8% in humans. No serious adverse health effects were identified at doses up to 20 g per day as reported in the human studies included in this opinion. Based on a subchronic oral toxicity study in rats, no observed adverse effect levels (NOAELs) of 3.6 and 4.4 g/kg bw per day in males and females were derived. The NOAELs were based on a statistically significant decrease in body weight. In another study in rats, the NOAELs for embryo toxicity/teratogenicity of D-ribose were 3.6 and 4.6 g/kg bw per day based on individual females. This NOAELs were primarily based on a statistically significantly higher incidence of one or multiple wavy ribs in the mid- and high-dose groups compared to control animals. No studies on children (10 to <14 years) and adolescents (14 to <18 years) were identified. Based on the included literature there was no evidence indicating that age affects tolerance for D-ribose. Therefore, in this risk characterisation a tolerance as for adults, based on body weight, were assumed for these age groups. The values used for comparison with the estimated exposure in the risk characterization are 20 g per day (corresponding to 286 mg/kg bw per day in a 70 kg adult) considered to be without appreciable health risk for most healthy adults and the NOAEL of 3.6 g/kg bw per day from the subchronic toxicity and embryotoxicity/teratogenicity studies in rats. From a daily dose of 3100 mg or 6200 mg of D-ribose, the intake levels are 71.4, 50.6 and 44.3 mg/kg bw per day and 142.6, 101.1 and 88.6 mg/kg bw per day for for children (10 to <14 years), adolescents (14 to <18 years) and adults (³18 years), respectively. The calculated MOE values from the rat study for a daily intake of 3100 mg per day were 50.4, 71.1 and 81.3 for children (10 to <14 years), adolescents (14 to <18 years) and adults (³18 years), respectively. The calculated MOE values for a daily intake of 6200 mg per day were 25.2, 35.6 and 40.6 for children (10 to <14 years), adolescents (14 to <18 years) and adults (³18 years), respectively. In this case, MOE values below 100 are regarded as acceptable since D-ribose is present in all cells in the body and the daily doses from food supplements are in the same order as the endogenous production, which ranges from 2.7 g per day (women) to 16.5 g per day (men) (Bioenergy Life Science Inc., 2008). VKM concludes that it is unlikely that daily doses of 3100 mg or 6200 mg D-ribose in food supplements causes adverse effects in children (10 to <14 years), adolescents (14 to <18 years) and adults (above18 years).

Comparing the effects of intake of sugar containing different levels of D-ribose in sugar on glycemic index and blood glucose response in healthy adults / 한국영양학회지

PURPOSE: To compare the extent to which three different levels of D-ribose in sugar reduce the glycemic index (GI) and blood glucose response in healthy adults. METHODS: Healthy adults (eight male and six female participants, n = 14) fasted for 14~16 h after eating the same dinner. Participants were then randomized to receive glucose, sucrose, sucrose containing 5% D-ribose (RB5), sucrose containing 10% D-ribose (RB10), or sucrose containing 14% D-ribose (RB14) every week on the same day for 10 weeks (repeating the sample twice). Blood samples were collected by finger prick before and 15, 30, 45, 60, 90, and 120 min after starting to eat. RESULTS: We observed a decreased glycemic response to sucrose containing D-ribose. GIs for sucrose, RB5, RB10, and RB14 were 67.39, 67.07, 47.57, and 45.62, respectively. GI values for sucrose and RB5 were similar to those for foods with a medium GI, and GI values for RB10 and RB14 were similar to those for foods with a low GI. The postprandial maximum blood glucose rise (Cmax) with RB14 was the lowest among the test foods. Cmax values for RB10 and RB14 were significantly lower than that for sucrose. CONCLUSION: The results of this study suggest that sucrose containing D-ribose has an acute suppressive effect on GI and Cmax. In addition, D-ribose active elements in sugar may be effective in preventing blood glucose spikes induced by sucrose intake.

Effects of D-ribose on High-energy Phosphate Metabolism of Skeletal Muscle Tissues of Tired Mice / 世界科学技术-中医药现代化

This article was aimed to study effect of D-ribose on the high-energy phosphate metabolism of skeletal muscle tissues of tired mice. The model was made by burden swimming. And then, the mice were divided into four groups, which were the model group, D-ribose group, caffeine group, and D-ribose with caffeine group). Intragastric administrations of drugs were given to all mice in four groups, three times per day. And all mice continued to swim for three days. The time of swimming was recorded. Gastrocnemius of mice were removed after swimming or 3 days later to measure the concentration of ATP, ADP, AMP and IMP with the HPLC. The results showed that compared with the control group, the time of burden s wimming was significantly prolonged for mice in the D-ribose group and the D-ribose with caffeine group. After three-day recovery, the concentration of ATP, AMP and IMP of gastrocnemius in the D-ribose group and the D-ribose with caffeine group mice was significantly increased. There was no significant difference in the caffeine group mice. It was concluded that D-ribose is involved in the high-energy phosphate metabolism of skeletal muscle tissues of tired mice . D-ribose promotes the recovery of ATP concentration in the gastrocnemius of tired mice, and prolongs the time of burden swimming. Therefore, it has a certain anti-fatigue effect .

Inhibitory Effect of Pentose on Biofilm Formation by Oral Bacteria

A number of bacterial species coexist in oral cavities as a biofilm rather than a planktonic arrangement. By forming an oral biofilm with quorum sensing properties, microorganisms can develop a higher pathogenic potential and stronger resistance to the host immune system and antibiotics. Hence, the inhibition of biofilm formation has become a major research issue for the future prevention and treatment of oral diseases. In this study, we investigated the effects of pentose on biofilm formation and phenotypic changes using wild type oral bacteria obtained from healthy human saliva. D-ribose and D-arabinose were found to inhibit biofilm formation, but have no effects on the growth of each oral bacterium tested. Pentoses may thus be good candidate biofilm inhibitors without growth-inhibition activity and be employed for the future prevention or treatment of oral diseases.

The Effect of Dissolved Oxygen Tension on the Fermentation of D-ribose / 微生物学通报

After comparing the varieties of parameters in batch culture under different dissolved oxygen tension by Bacillus pumilus, we found that the demand of cell on oxygen in different phase isn' t consistent. Based on the analys is of the metabolic pathway of oxygen and the mechanism of the effect of dissolved oxygen tension on fermentation of D-ribose, a two-stage oxygen-supply control mode was proposed and experimentally proved to be available. High ribose yield and high glucose consumption rate were achieved during whole process for 44h, and the ultimate ribose concentration and cell concentration were 5.0% and 18.8% higher than former respectively.