Abstract: Effects of different extraction conditions for 95% ethanol extract of star anise were investigated on bacteriostasis of the extract against putrefying bacteria, which were isolated form low-temperature meat product. The optimal extraction conditions for antimicrobial substance from star anise are as follows: extracting for 3 h at 60 ℃ with raw material to 95% ethanol ratio 1:12 (m/V), which were obtained by single factor test and orthogonal rotational regression design. In virtue of artificial neural networks, the model describing the effects of extraction conditions on antimicrobial capacity against the putrefying bacteria was established. The results showed that the artificial neural networks method is more reliable than regressive analysis method.

Key words: star anise, antimicrobial test, BP artificial neural network