Open AccessEstimation of Frankia growth using Bradford protein and INT reduction activity estimations: application to inoculum standardization
Author(s) -
Prin Y.,
Neyra M.,
Diem H.G.
Publication year - 1990
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1990.tb04181.x
Subject(s) - frankia , int , absorbance , formazan , bradford protein assay , chemistry , chromatography , biomass (ecology) , methanol , biochemistry , biology , bacteria , symbiosis , root nodule , genetics , computer science , operating system , organic chemistry , agronomy
The growth of Frankia spp. strain ORS 020607 in BAP medium was studied by using two methods simultaneously: determination of Bradford protein content and INT (2‐( p ‐iodophenyl‐3‐( p ‐nitrophenyl)‐5‐phenyl tetrazolium chloride ) reduction activity (IRA). With the latter test, red formazan crystals formed intracellularly were extracted with methanol. Colouration intensity was estimated by absorbance spectrophotometry at 490 nm. The protein content and IRA of the culture were monitored for 96 days. IRA appeared to reflect the ‘metabolically active’ biomass of Frankia more accurately than the Bradford protein estimations.