enantioselective biotransformation of prochiral ketone via

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Enantioselective Biotransformation of Prochiral Ketone via Daucus carota Ryan Smith, Charlie Knox, and Elizabeth Davis Faculty Advisor: Dr. Michele Harris Department of Chemistry Stephen F. Austin State University Incubated carrots with ketone, extracted alcohol product, measured optical activity, and verified product using IR spectroscopy. Incubated carrot strips in buffer with low percent detergent . Used ammonium sulfate precipitation. Analyzed both supernatant and pellet using SDS-PAGE. Placed known quantity of purified alcohol on disk and placed on a Petri dish growing bacteria. Biotransformations of prochiral ketones can be performed using plant cells. The benefits of using plant cells include low cost, environmentally sound procedures compared to conventional chemical processes, and the stereospecific nature of the reaction. 1,2 Benzofuran-2-yl methyl ketone was reduced to (- )-benzofuran-2-yl-ethanol after incubation with carrots in water. The reaction was enantioselective in that it produced the S-isomer as indicated by optical activity. Currently, attempts to isolate the carrot enzyme and antimicrobial studies of the (-)-benzofuran-2-yl- ethanol product are underway. SDS-PAGE Results Funding for this project was provided by the Robert A. Welch Departmental Grant (AN-0008) and from SFASU Office of Research and Sponsored Programs Faculty Research Grant 1. Ravia, S. et.al. J.Chem.. 2006, 83, 1049-1051 2. Yadav, J.S.; et.al. J. Org. Chem., 2002, 67, 3900-3903 3. Yang, Z.; et.al. J. Micro. Biotech., 2008, 35, 1047-1051 Abstract Methods References Antibacterial Results Funding Reaction Possible Reaction Pathway STD 10 μl RS 10 μl SN Blank Blank 5μl RS 50% 5μl SN 50% 739.60 803.44 878.92 941.46 1005.68 1022.22 1073.48 1152.80 1172.12 1253.29 1300.84 1453.85 3349.33 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 %T 500 1000 1500 2000 2500 3000 3500 4000 Wavenumbers (cm-1) Optical Activity Results The optical activity of the alcohol product agreed with literature values of -16.4 and the percent yield was 37%. IR Spectroscopy Results Ketone Alcohol Ring of inhibition of bacterial growth. The concentration of the alcohol was 1.5 mg/ml. Arrows indicate protein bands isolated from carrot surface. Acknowledgements The following students collaborated on this project: Betty Abraha, Adrianne Crandall, Natasha Impink Hernandez, Olivia Korpe, John Sharp, and Kenneth Smith. Conclusions This undergraduate group effort has worked out the preliminaries for: isolating pure, optically active alcohol demonstrated carrot protein can be removed from surface of carrot, and the alcohol may some antibacterial properties at fairly high concentrations.

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Enantioselective Biotransformation of Prochiral Ketone via Daucus carota Ryan Smith, Charlie Knox, and Elizabeth Davis

Faculty Advisor: Dr. Michele Harris Department of Chemistry

Stephen F. Austin State University

Incubated carrots with ketone, extracted alcohol product, measured optical activity, and verified product using IR spectroscopy.

Incubated carrot strips in buffer with low percent detergent . Used ammonium sulfate precipitation. Analyzed both supernatant and pellet using SDS-PAGE.

Placed known quantity of purified alcohol on disk and placed on a Petri dish growing bacteria.

Biotransformations of prochiral ketones can be performed using plant cells. The benefits of using plant cells include low cost, environmentally sound procedures compared to conventional chemical processes, and the stereospecific nature of the reaction.1,2

Benzofuran-2-yl methyl ketone was reduced to (-)-benzofuran-2-yl-ethanol after incubation with carrots in water. The reaction was enantioselective in that it produced the S-isomer as indicated by optical activity. Currently, attempts to isolate the carrot enzyme and antimicrobial studies of the (-)-benzofuran-2-yl-ethanol product are underway.

SDS-PAGE Results

Funding for this project was provided by the Robert A. Welch Departmental Grant (AN-0008) and from SFASU Office of Research and Sponsored Programs Faculty Research Grant

1. Ravia, S. et.al. J.Chem.. 2006, 83, 1049-1051

2. Yadav, J.S.; et.al. J. Org. Chem., 2002, 67, 3900-3903

3. Yang, Z.; et.al. J. Micro. Biotech., 2008, 35, 1047-1051

Abstract Methods

References

Antibacterial Results

Funding

Reaction

Possible Reaction Pathway

ST

D

10 µ

l R

S

10 µ

l S

N

Bla

nk

Bla

nk

5µl

RS

50%

5µl

SN

50%

739.

60

803.

4487

8.92

941.

4610

05.6

8

1022

.22

1073

.48

1152

.80

1172

.12

1253

.29

1300

.84

1453

.85

3349

.33

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

105

%T

500 1000 1500 2000 2500 3000 3500 4000

Wavenumbers (cm-1)

Optical Activity Results

The optical activity of the alcohol product agreed with literature values of -16.4 and the percent yield was 37%.

IR Spectroscopy Results

Ketone

Alcohol

Ring of inhibition of bacterial growth. The concentration of the alcohol was 1.5 mg/ml.

Arrows indicate protein bands isolated from carrot surface.

Acknowledgements

The following students collaborated on this project: Betty Abraha, Adrianne Crandall, Natasha Impink Hernandez, Olivia Korpe, John Sharp, and Kenneth Smith.

Conclusions

This undergraduate group effort has worked out the preliminaries for: isolating pure, optically active alcohol demonstrated carrot protein can be

removed from surface of carrot, and the alcohol may some antibacterial

properties at fairly high concentrations.