Table 1 : Inhibition of Kazakhstan and US HA-MRSA by Actinomycetes Antagonists.

Antagonist #
and Source ( pH)
Zone of Inhibition (Kazakhstan HA-MRSA) (mm) United States HA-MRSA Zone of Inhibitione (mm)
Growth Media
1a 2b 3c
2-2 mud (9.1) 0 18 NG 0
6-12 rhizosphere (8.6) 0 25 NG 0
18-7 sandy soil (10.0) 13 44 NG 0
19-25 soil (9.3) 0 35 0 11.5
33-1 mud (9.6) NGd 49 39 10.0
36-3 meadow soil (8.3) 10 24 23 0
41-8 saline soil (10.0) 11 29 15 7.0
48-29 sandy soil (10.0) 0 32 22 20.5
51-9 rhizosphere (9.5) 10 46 10 0
58-22 rhizosphere (8.9) 0 18 14 22.5
72-1 soil (9.6) 0 50 NG 0
96-1 soil (8.6) 11 26 19 0
Q4-39 soil (10.0) 0 16 15 0
Y-45 rhizosphere (9.8) 0 20 16 0

a Growth Medium 1 = Modified Bennett's pH=7.2
b Growth Medium 2 = Modified Bennett's pH=7.2, 5% NaCl
c Growth Medium 3 = Modified Bennett's pH=9.0, 0.5% Na2CO3
d NG = No growth of the Actinomycetes producer
e Zone of Inhibition for US HA-MRSA reported is an average of multiple disk diffusion assays (DDA's).
Notes on Growth Medium:
Modified Bennett's Growth Media 1 a , 2 b and 3 c comprised of glucose (0.2%), peptone (0.2%), yeast extract (0.1%), and agar (2%), were used to grow actinomycete strains and incubated at 28°C, and growth was checked after 1-2 weeks incubation. Purified isolates were investigated in antibacterial tests against Kazakhstan HA-MRSA using the standard disk diffusion assay; strains with positive anti-MRSA activities were chosen for preparation of Kazakhstan (KZ) extracts.
Notes on Antagonistic KZ extract antibacterial testing against Kazakhstan and United States HA-MRSA:
Fourteen KZ extracts (first column of Table 1 labeled as "Antagonistic #") containing components with antibacterial activities shipped from Kazakhstan were tested in antagonistic tests against United States HA-MRSA grown on Mueller-Hinton agar plates, using standard Kirby-Bauer disk diffusion assay. Dilution of KZ extracts and antibacterial testing were performed using similar conditions for HA-MRSA isolates from Kazakhstan and United States, using our previously reported methods [8]. Sterile disks containing 10 µg/mL of crude powder of KZ extracts were placed on fresh plates of the Mueller-Hinton agar seeded with bacterial suspensions at a cell density of 5×105 CFU/ml of overnight cultures of the test HA-MRSA strains. The diameters of the zones of inhibition of growth (mm) around the disks measured after incubation periods of 18 h at 37°C presented are average values from triplicate experiments.

Azizan et al.Journal of Pharmaceutical Technology and Drug Research  2013 2:14DOI : 10.7243/2050-120X-2-14