Effects of Salvia miltiorrhiza extract on growth of Rhodobacter sphaeroides

Objective To study the effects of Salvia miltiorrhiza extract on the growth of Rhodobacter sphaeroides(photosynthetic bacteria,PSB).Methods The effects of S.miltiorrhiza extract on the growth of R.sphaeroides were researched by observing the effects of S.miltiorrhiza and general culture medium at concentration on the number,growth curve,dehydrogenase activity,and absorption spectra of photosynthetic pigment of alive R.sphaeroides.Results After adding S.miltiorrhiza extract into culture medium for 3 d,the number of alive R.sphaeroides was increased in 1.6 times,the delay period was shortened and the expotential and stationary periods were advanced which could shorten the growth period of R.sphaeroides,the dehydrogenase activity of R.sphaeroides was improved in 6.6 times as before.When S.miltiorrhiza concentration was higher,the absorption of photosynthetic pigment of alive R.sphaeroides was getting lower,which was almost insusceptible while S.miltiorrhiza concentration was lower.When S.miltiorrhiza concentration was high,the formation of carotenoid which was in short wavelength region was influenced and the peak at 855 nm was approximately blue-shifted to 863 nm.Conclusion When adding S.miltiorrhiza extract into culture medium,the growth and the activity of R.sphaeroides could be improved,the growth cycle be shortened and the formation of photosynthetic pigment be effected.