For extraction of bioactive compounds from endophytic bacteria, different solvents can be used to get crude extract. I strongly recommend ethyl acetate. Bioactive volatile compounds from ethyl acetate crude extract can be identified using gas chromatography-mass spectrometry (GCMS). Bioactive nonvolatile compounds from the same crude extract can be identified using liquid chromatography-MSMS (LC-MSMS).

The selected endophytic bacteria isolate crude extracts can be prepared by inoculating 100 μl of bacterial suspension into 250 ml nutrient broth (NB). The bacteria cultures then incubate at 25±2°C for five days on a rotating shaker (150 rpm). The culture then centrifuge at 12000 rpm for 20 min to separate the bacterial cells from their metabolites. The supernatant will be collected, and the pellet will be discarded. The supernatant will be extracted with an equal volume of (250ml) ethyl acetate and then leave overnight. The free cell extracts will be evaporated using a rotary evaporator at 45°C with 225 rpm, and the residues will be re-dissolved in methanol.

Hello,

I assume you have already isolated the endophytic bacteria from the tissue.

For isolation of bio-active compounds you can choose one of these two ways depending up on you research interest.

1. You can first study the effect of your bacterial crude extract for one or more bio-activity (in-vitro/in-vivo), if you find better activity then start separating the each bio-molecule responsible for the activity as suggested in previous answer.

2. In case if you want to isolate particular known bio-active compound, you can use same extraction methodology used to isolate that compound from plant or fungi (refer papers).

Hope this helps.

Vijaya

doi.org/10.1007/s13596-019-00410-z