@article{article_1556127, title={Sensitivity of pure cultures of some Gram-positive and Gram-negative rumen bacteria to sigla storax (Liquidambar orientalis)}, journal={Mediterranean Veterinary Journal}, volume={10}, pages={432–438}, year={2025}, author={Demirtaş, Ahu}, keywords={antibiotic feed additives, antimicrobial, minimum inhibitory concentration (MIC), phytochemicals, Styrax liquidus}, abstract={Extracted from the wounded bark of the Liquidambar orientalis tree, sigla storax is a semi-viscous, balsamic resin. This study aimed to evaluate the effects of sigla storax on the growth of pure cultures of select Gram-positive and Gram-negative rumen bacteria, thereby elucidating its potential mode of action on rumen metabolism as an alternative antibiotic feed additive. Under strictly anaerobic conditions, the antimicrobial activity of sigla storax was assessed using the broth microdilution method. With the exception of Streptococcus bovis, storax demonstrated potential antimicrobial activity on all bacteria at doses starting from 1-2 mg/ml (P <0.05). The most susceptible bacterium was Ruminococcus flavefaciens, which was inhibited at 4 mg/ml sigla, while the most resistant was S. bovis, which showed no inhibition. For other Gram-positive bacteria, the minimum inhibitory concentration (MIC) varied: 16 mg/ml for Butyrivibrio fibrisolvens, and 32 mg/ml for Ruminococcus albus, Eubacterium ruminantium, and Methanobacterium formicicum. Interestingly, at lower doses, sigla storax exhibited a growth-stimulating effect on E. ruminantium (0.06-0.125 mg/ml) and S. bovis (0.125-2 mg/ml) (P <0.05). The Gram-negative Megasphaera elsdenii also showed a slight stimulatory response to sigla storax at concentrations of 0.06-0.5 mg/ml (P <0.05). However, at 32 mg/ml, sigla storax inhibited both Gram-negative bacteria tested: M. elsdenii and Fibrobacter succinogenes. While Gram-positive bacteria generally exhibited higher sensitivity to sigla storax compared to Gram-negative bacteria, the study concluded that its mechanism of action differs from typical antibiotic feed additives. This distinction is due to sigla storax’s antibacterial activity against Gram-negative bacteria and its stimulatory effects on certain Gram-positive bacteria.}, number={1}, publisher={Burdur Mehmet Akif Ersoy University}