EPS Extraction Procedure

EPS Extraction Procedure

Total Estimated Time: 8 hours

EPS Extraction Estimated Time: 4.5 hours

Method: Optimized method developed in Kirisits lab

Make Buffer: 10 mM Tris, 10 mM EDTA, 2.5% NaCl, pH 8

  1. 500 mL DDI

  2. 7882 g Tris-HCl

  3. 861 g EDTA*2H2O

  4. 5 g NaCl

  5. Adjust to pH 8 with 5 N NaOH

  6. Autoclave

Do Extraction:

  1. 15-mL conical

  2. 2 ± 0.05 g GAC (wet weight)

  3. 10 mL extraction buffer

  4. Vortex for 1 min at max intensity

    1. Attach tubes to vortex adapter

  5. Incubate horizontally at 35 °C for 4 h with shaking at 200 rpm

    1. Use shaker-incubator and secure with tape

  6. Centrifuge for 10 min at 10,000xg

  7. Filter supernatant through 0.45-mm nylon filter into fresh 15-mL conical

    1. Pre-soak the nylon filters in ultrapure water in a glass beaker

    2. Use a plastic transfer pipette to transfer the supernatant to a plastic syringe with a filter attached

 

At this point, the supernatant may be saved in 20oC refrigerator for up to 5 days before polysaccharide and protein processing.

 

Polysaccharides/Carbohydrates Estimated Time: 2 hours

Method: Phenol-sulfuric acid method, modified from Masuko et al. 2005

Application: Pure culture and Mixed culture GAC.

Linear Range: ~5-100 mg glucose/L

Location: UNDER FUME HOOD!!

Standards: Store at 4 °C in sterile bottle.

  1. Prepare 1 g/L stock solution (SS). Add 0.25 g glucose to a 250-mL volumetric flask. Dilute to volume with DDI.

  2. Run a standard curve every time

Standard Conc. (mg/L)

Volumetric Flask (mL)

Volume of SS (mL)

5

100

0.5

10

100

1

25

100

2.5

50

100

5

100

100

10

 

Phenol Solution:

  1. Make 5% (w/v) phenol solution

  2. Add 0.5577 mL of concentrated (89%) phenol to 10 mL DI

Procedure:

  1. Turn on small water bath to 90 °C

    1. Check the water level in the bath so that water does not enter the tubes

  2. Add 150 mL of sample to 13-mm glass test tube.

  3. Move to the hood

  4. Add 450 mL of concentrated H2SO4.

  5. Quickly add 90 mL of 5% (w/v) phenol.

  6. Cap and vortex gently.

  7. Place samples in 90 °C water bath for 10 min.

  8. Cool at room temperature for 5 min in a water bath.

  9. Vortex gently. Transfer 200 mL into a 96-well plate in duplicate.

  10. Measure absorbance at 490 nm on the plate reader.

  11. Dispose of the plate in the black waste bucket.

Proteins Estimated Time: 1.5 hours

Method: Pierce BCA Protein Kit

Linear range: 5-250 mg BSA/L

Standards: Make according to manufacturer’s instructions.

Vial

Vol. Diluent (mL)

Vol.  & Source BSA (mL)

Final BSA Conc. (mg/L)

A

700

100 of Stock

250

B

400

400 of A dilution

125

C

450

300 of B dilution

50

D

400

400 of C dilution

25

E

400

100 of D dilution

5

 

Procedure:

  1. Turn on large water bath and set to 60 °C

  2. Make mixed reagent.

    1. Multiply # of samples to be analyzed by 2. This is the volume (mL) of Reagent A you will use.

    2. Measure Reagent A in a graduated cylinder.

    3. Pour into a 100-mL wide-mouth bottle.

    4. Divide volume of Reagent A by 50. This is the volume (mL) of Reagent B to add.

    5. Add Reagent B to Reagent A. Swirl gently to mix.

  3. Add 100 mL of sample to a 13-mm glass test tube.

  4. Add 2 mL of the mixed reagent to each test tube and cap.

  5. Vortex gently to mix.

  6. Place samples in the 60 °C water bath and incubate for 30 min.

  7. Vortex gently. Transfer 200 mL to a 96-well plate in triplicate.

  8. Measure absorbance at 562 nm on the plate reader.

  9. Dispose of the plate in the black waste bucket.

 

Total Solids Estimated Time: 0.5 hours

  1. Label and weigh aluminum weigh pan

  2. Scrape media from bottom of extraction tube into the weigh pan using a metal spatula

  3. Dry overnight in 105 C oven

  4. Transfer to desiccator to cool

  5. Weigh pan + total solids (TS)

 

Calculations