Synthesis of Perbenzoylated Carbohydrates in Preparation for Anthocyanin Pigment Characterization

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Synthesis of Perbenzoylated Carbohydrates in
Preparation for Anthocyanin Pigment
Characterization

• Brandon Lew
• March 15, 2006

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Introduction

• Purpose
• To develop a technique for carbohydrate
  characterization through NMR so that anthocyanin
  carbohydrate tails may be characterized.

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Anthocyanins
http//www.mariquita.com/images/photogallery/straw
berries.jpg
http//www.personal.psu.edu/staff/m/h/mhl100/image
s/blueberries.jpg
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Carbohydrate Tails
Anthocyanidin Base







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Anthocyanin Characterization

• NMR of anthocyanins
• Seeram et al. 2002
• Separation of tails
• Takeoka et al. 2005
• Combine to perform NMR on separated tails

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Carbohydrates
Chair
Chain
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Perbenzoylation

• Levene and Meyer (1927)
• Glucose
• DAccorso et al. (1981)
• NMR data of many monosaccharides

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Perbenzoylation (Protocol 1)
ß-glucose

Perbenzoylated-ß-glucose
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Purification

• Thin-layer chromatography (TLC)
• Column chromatography
• High-pressure liquid chromatography (HPLC)

http//www.hamline.edu/depts/chemistry/facility/im
ages/hplc.jpg
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Nuclear Magnetic Resonance Spectroscopy (NMR)
Excited State
Magnetic Field
EM radiation
Radio wave
Detector
1H/13C
Ground State
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Protocol 1 Results 1H NMR of perbenzoylated ß
glucose
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Protocol 1 Results HPLC of perbenzoylated maltose
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Protocol 1 Results 13C NMR of perbenzoylated
maltose
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Perbenzoylation (Protocol 2)
ß-glucose

Perbenzoylated-ß-glucose
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Protocol 2 Results 1H NMR of perbenzoylated ß
glucose
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Protocol 2 Results HPLC of perbenzoylated ß
glucose
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Procedure 2 Results 1H NMR of perbenzoylated a
glucose
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Conclusion

• Protocol 1 contaminated
• Some disaccharides selectively benzoylated

ß-glucose
Perbenzoylated-ß-glucose
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Conclusion

• Protocol 2 purer, quicker
• Perbenzoylation works for characterization

ß-glucose
Perbenzoylated-ß-glu
cose
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Future Work

• Use perbenzoylation to characterize carbohydrate
  tails of anthocyanins
• Anthocyanins differ by their tails
• Important for developing anti-oxidant food
  additives

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Acknowledgements

• Dr. Matachek
• Hamline University
• Ms. Fruen
• Ms. Richter, Bill Mitchell
• Team Research

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Synthesis of Perbenzoylated Carbohydrates in
Preparation for Anthocyanin Pigment
Characterization

• Brandon Lew
• March 15, 2006