Biodegradation of caffeine by whole cells of tea-derived fungi Aspergillus sydowii, Aspergillus niger and optimization for caffeine degradation

Table 5 Comparison of the kinetic parameters for caffeine degradation on different reaction temperatures (1200 mg/L of caffeine,15d. pH 7.0)^a

Reaction temperature (°C)	Fungal dry mass (g)	C_caffeine,f (mg/L)	C_{theophylline,f} (mg/L)	C_{3-methylxanthine,f} (mg/L)	Q_caffeine (mg/L d)	Q_theophylline (mg/L d)	Y_{theophylline/caffeine}	% of caffeine degraded
25	0.22 ± 0.02^A	121.6 ± 14.4^A	478.8 ± 20.2^A	196.6 ± 7.5^A	71.9 ± 1.0^B	31.9 ± 1.3^A	0.44 ± 0.02^A	89.9 ± 1.2^B
30	0.22 ± 0.03^A	105.0 ± 16.9^A	549.4 ± 29.3^B	178.7 ± 10.8^B	73.0 ± 1.1^B	36.6 ± 2.0^B	0.50 ± 0.03^B	90.5 ± 1.4^B
35	0.19 ± 0.02^A	202.0 ± 15.7^B	618.4 ± 18.8^C	149.8 ± 13.2^B	66.5 ± 1.0^A	421.2 ± 1.3^C	0.61 ± 0.02^C	83.2 ± 1.3^A

^aAll kinetic parameters were calculated according to Sirisansaneeyakul and others (2013) [34]
All data are presented as mean ± SD, ^A-Cp < 0.05 in the same column
Concentrations of caffeine, theophylline and 3-methylxanthine determined by HPLC
Ccaffeine,f the final caffeine concentration (mg/L), Ctheophylline,f the final theophylline concentration (mg/L), C3-methylxanthine,f the final 3-methylxanthine concentration (mg/L), Qcaffeine the volumetric rate of caffeine degradation (mg/L d), Qtheophylline the volumetric rate of theophylline production (mg/L d), Ytheophylline/caffeine theophyline yield on caffeine (mg/mg)

ISSN: 1471-2180