I will focus on THREE things today

Transcription

1 Bioavailability of the most predominant 5-MTHF in humans using the emerging LC-MS/MS technique Dr. Shyamala Vishnumohan (former PhD student from UNSW),Princess Margaret Hospital, Perth and Dr. Jayashree Arcot Food Science and Technology School of Chemical Sciences and Engineering, Sydney 52 Australia I will focus on THREE things today 1. Research background 2. Research methodology 3. Results

2 Research Background The public derives its folate not only from synthetic folic acid.

3 also from natural sources! Despite 35 years of investigation.. Literature to date suggests that the food folates are 1-98% bioavailable compared to folic acid (Tamura & Stokstad,1973; Brouwer et al;1999; Winkels et al,7)

4 Research Objective The bioavailability of dietary 5-methyl tetrahydrofolate (5-MTHF) in a whole day s mixed diet (a form predominant in foods) relative to supplemental 5-methyl Tetrahydrofolate in the selected population Research methodology

5 Facts about the project country Population not exposed to synthetic folic acid No data on processed (cooked) foods! Study design Study period: 3 Months Screening for participants (n=) Unwilling to participate (n=1) Willing to participate (n=) Subjects met the inclusion criteria (N=22) Excluded due to deficiency in folate/iron/b12 (n=38) High folate diet group (n=11) µg Supplementation group (n=11) µg

6 Dietary analysis and Planning What is the daily intake of dietary folate in the selected population???? Typical South Indian Diet Breakfast (or ) Dinner Lunch

7 A microbiological assay lab was set up in India in one month! 45 foods were prioritised based on a 24 hour dietary recall and FFQ, Standardised and analysed for total folate contents Profiling the folate vitamers External standards RT: AA: NL: 3.26E4 m/ z= F: + p 442.@3. [ ] MS Folic acid Internal standards RT: AA: NL: 3.78E4 m/ z= F: + p 447.@3. [ ] MS RT: 3.63 AA : NL: 1.71E4 m/ z= F: + p 446.@3. [ ] MS THF RT: 3.65 AA: RT: AA: NL: 1.E4 m/ z= F: + p 451.@3. [ ] MS Relative Abundance Relative abundance RT: 4.1 AA: RT: 1.76 MA: Time (min) RT: AA: NL: 1.63E4 m/ z= F: + p 4.@25. [ ] MTHF MS 5-MTHF NL: 2.38E4 m/ z= F: + p 47.@25. [ ] MS L4 R1 1-FFA NL: 1.E4 m/ z= F: + p 474.@22. [ ] MS 5-Formyl THF Time (min) Relative Abundance RT: 4.3 NL: 1.76E4 AA: m/ z= F: + p 465.@25. [ ] MS RT: 1.78 NL: 2.45E4 AA: m/ z= F: + p 475.@25. [ ] MS RT: NL: 1.37E4 AA: m/ z= F: + p 479.@22. [ ] MS Time (min)

8 Using LC-MS/MS % 3% 5 Methyl THF 5-Formyl THF Typical diet before entering the study (429 µg g folate/day) 57% Folic acid 6% 3% Experimental diet formulation (Diet predominant in 5-MTHF) 5 3% 61% 5 Methyl THF from daily diet 5 Methyl THF from snack foods 5-Formyl THF Folic acid What did we measure? Serum folate (Chemiluminescence and LC-MS/MS) Red cell folate (Chemiluminescence and LC-MS/MS)

9 Results Relative Bioavailability based on serum folate was 41% Folate (5MTHF) rich diet group Supplement group A (B) R-Max B (A) R-Max Maximal bioavailability = 24% Maximal bioavailability = %

10 Relative Bioavailability based on RBC folate was 45.5% Mean baseline Mean W12 RBC Mean increase in Study groups RBC folate folate (ng/ml) RBC folate (ng/ml) # (ng/ml) Group A (5-MT diet rich group) Group B (5-MT supplement group) ( % mean increase in serum folate at R max ) GroupA 362 Bioavailablility + 87 = 1 ( % mean increase 1 in serum folate at 2 R max + ) GroupB 79 Re lative Maximal % 134% # Statistically significant P=.1 Conclusion Relative bioavailability based on serum folate was 41% Relative bioavailability based on RBC folate was 45.5 %

11 Strengths of the study Long term study Population not exposed to synthetic folic acid Test diet representative of a mixed varied diet Test diet similar to traditional diet LC-MS/MS adds accuracy to the values generated for biomarkers and diets Acknowledgement Study Participants (India) Dr.Sheela Ramachandran,, PSG college (India) IPRS,School of Chemical Sciences and Engineering,BMSF Dr.Russ Pickford,UNSW

12 Thank you! Questions???