Availability of vitamin B 6 from different food sources

Abstract

The present study was conducted to investigate the precaecal digestibility of vitamin B6 from selected food sources including eggs, bananas, white cabbage, corn, milk powder, fish, barley, soybeans, brown rice, wheat bran, brewer's yeast, rye and soybean meal. These foods were chosen for their relevance in human and animal nutrition and prepared as they are usually eaten by humans. As confirmed by further investigations the precaecal digestibility is a valuable measure for determining the availability of native B-vitamins. Therefore, pigs were fitted with an end-to-end ileo-rectal anastomosis for digesta passing straight from ileum to rectum, thus avoiding endogenous vitamin synthesis by the colon. Three weeks after surgery the digestibility experiments were carried out during which the animals were fed various experimental diets for a period of 12 days and digesta were collected quantitatively twice a day during the final 5 days of this period. The concentration of vitamin B6 in foods and chyme was determined by high pressure liquid chromatography. Precaecal digestibility of vitamin B6 from all tested food sources ranged from 51 to 91% in the following order: cabbage diet > banana diet > fish diet > milk powder diet > brewer's yeast diet > soybeans diet > soybean meal diet > egg diet/corn diet > barley diet > wheat bran diet > rye diet. Only boiled brown rice had a very low vitamin B6 availability of 16%. The digestibility of vitamin B6 from plant products (excluding the rice) was on average 10% lower when compared with animal products (71 versus 79%).

Effects of vitamin B6 metabolism on oncogenesis, tumor progression and therapeutic responses

“…3 The major sources of vitamin B6 include whole grain, nuts, vegetables and bananas, which are particularly rich in PN, as well as raw milk and distinct types of meat, which contain high amounts of PM and PL. 4 According to the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (http://www.chem. qmul.ac.uk/iubmb/enzyme/), 5 44% of all classified enzymatic activities rely on PLP as an obligate prosthetic group.…”

Evaluation of vitamin B6intake and status of 20- to 64-year-old Koreans

“…The bioavailability of nutrients in foods and dietary supplements is an important issue in evaluating the adequacy of diets and resolving inadequate status [ 25 ]. In an animal study, the bioavailability of vitamin B 6 in humans consuming a mixed diet was approximately 75% [ 32 ] and the digestibility of vitamin B 6 from animal products was approximately 10% greater than from plant sources [ 33 ]. Pyridoxine 5'-β-D-glucoside, a glycosylated from of vitamin B 6 commonly found in foods of plant origin, is approximately 50% as bioavailable as other forms of vitamin B 6 [ 8 ].…”

Toward Eradication of B-Vitamin Deficiencies: Considerations for Crop Biofortification

“…Good sources of dietary B6, besides animal-derived products such as fish and meat, are fresh vegetables including carrots and onions ( USDA, 2016 ; Fudge et al, 2017 ). However, bioavailability should be considered, given the observations that up to half of the B6 pool could be lost as a result of incomplete digestibility, which is found to be more problematic in plant-based food sources compared to animal products ( Roth-Maier et al, 2002 ). Furthermore, the most consumed staple crops in the world are considered poor sources of dietary B6 ( Fudge et al, 2017 ) ( Table 1 ).…”