Before try any biochemical test you could check if the 16S rRNA gene is amplified by actinomycete specific primers...

In this way I suggest the primers S-C-Act-0235-a-S-20 and S-C-Act-0878-a-A-19 (Stach, J. E., Maldonado, L. A., Ward, A. C., Goodfellow, M., & Bull, A. T. (2003). New primers for the class Actinobacteria: application to marine and terrestrial environments. Environmental Microbiology, 5(10), 828-841)

After that, and if your intention is seek for a better taxonomic position of your isolates, you could follow the directions found in Stackebrandt, E., Frederiksen, W., Garrity, G. M., Grimont, P. A., Kämpfer, P., Maiden, M. C., ... & Whitman, W. B. (2002). Report of the ad hoc committee for the re-evaluation of the species definition in bacteriology. International journal of systematic and evolutionary microbiology, 52(3), 1043-1047.

Good lucky

you should make the 16s analysis, is better for actinobacteria

Me to prefer to go for 16s r-RNA gene amplification and identification. Among actinobacteria, only streptomyces sp. are easy to identify. Streptomyces, smell like moist soil and when grown in the agar plate or slant their colonies are submerged in the agar media. Mr. Zucchi has suggested good references, for more knowledge you can refer.