Mmushi T MSc (Microbiology).pdf

CHAPTER SIX
APPENDICES
6.1. Appendix A: Solutions
6.1.1. Preparation of Vanillin sulphuric acid
0.1 g Vanillin (Sigma-Aldrich, Batch No. 086K3676)
28 ml Ethanol (Reidel-de Haen, Batch No. 32221)
1 ml Sulphuric acid 95-97% (Fluka, Batch No. 84720)
Vanillin powder of 0.1 g was weighed into a dark brown coloured bottle, 28 ml of
ethanol was added into the same bottle, and 1 ml of sulphuric acid was lastly added
slowly into the bottle and shaked the mixture. The recipe was followed in this order with
the acid. The mixing was done at room temperature. Vigorously shaking of the mixture
insured complete dissolving of the ingredients and resulting in a homogenous mixture of
vanillin sulphuric acid.
6.1.2. Preparation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) solution
0.2 g DPPH (Sigma-Aldrich, Cat.: D9132)
100 ml Methanol (Sigma-Aldrich, Batch No. 34860)
DPPH of 0.2 g was weighed and added it into a brown bottle and added 100ml of
methanol into the same brown bottle. The mixture was shaked to dissolve the DPPH.
The DPPH solution was stored in the fridge until needed.
6.1.3. Preparation of p-iodonitrotetrazolium chloride (INT) solution
0.2 g p-iodonitrotetrazolium chloride (Sigma-Aldrich, Batch No. 18377-5G)
100 ml distilled water
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