Identificação Bioquímica
Interpretador para o tubo de Rugai com lisina (modificado IAL). Insira as reações de glicose, gás, H2S, lisina, motilidade, urease, sacarose e indol para identificar o gênero do isolado.
Rugai with lysine
Mark the reactions read on the modified Rugai (IAL) tube and get the compatible genera and species, with divergences flagged test by test.
Glucose (base)
Bottom of the tube
Common reading pitfall
Reading the butt after 24 h may reverse the yellow (alkalinisation): read between 18 and 24 h.
Gas
Bubbles or displacement of the butt
Common reading pitfall
An air bubble trapped during inoculation mimics gas: compare with an uninoculated tube from the same lot.
H2S
Blackening of the butt
Common reading pitfall
Heavy H2S masks the acid butt: with full blackening, consider glucose as fermented.
Lysine deaminase
Top of the slant
Common reading pitfall
Deaminase is read at the top of the slant and fades over time: late reading gives false negatives for Proteus/Providencia/Morganella.
Lysine decarboxylase
Lysine column
Common reading pitfall
The column must turn yellow first (fermentation) and only then purple; purple from the start is not a valid reaction.
Motility
Turbidity beyond the stab line
Common reading pitfall
A crooked stab or a needle entering twice creates a turbid track that mimics motility.
Urease
Urea slant
Common reading pitfall
Weak urease (Klebsiella, Citrobacter) only appears after 24 h and may be read as negative at 18 h.
Sucrose
Sucrose slant
Common reading pitfall
Late sucrose fermentation (S. sonnei, Serratia) requires a 48 h re-read before reporting it negative.
Indole
After 3 drops of Kovac’s reagent
Common reading pitfall
Indole is the last test: adding Kovac's before the other readings invalidates the whole tube.
Mark at least one test to see the possibilities.
Support reading only. Biochemical profiles overlap: confirm by seroagglutination, additional tests, or automated identification before releasing the report.
Get the free Bench Kit
I'll send the PDF Bench Kit: agar guide, Gram staining table, Rugai guide, dilution mini-table and a BrCAST/EUCAST antibiogram checklist.
Identificou a bactéria? Interpretar os halos de antibiograma (BrCAST) →
Precisa de UFC/mL ou diluição? Ver as calculadoras de bancada →