Essential Oil of Zingiber cassumunar Roxb. and Zingiber officinale Rosc.: A Comparative Study on Chemical Constituents, Antibacterial Activity, Biofilm Formation, and Inhibition of Pseudomonas aeruginosa Quorum Sensing System.

Pseudomonas aeruginosa can regulate its pathogenicity via quorum sensing (QS) system. Zingiber cassumunar and Z. officinale have been used for the treatment of infectious diseases. The study aimed to evaluate and compare the chemical constituents, antibacterial, and QS inhibitor of Z. cassumunar essential oils (ZCEO) and Z. officinale essential oils (ZOEO). The chemical constituent was analysed using GC/MS. Broth microdilution and spectrophotometry analysis were used to evaluate their antibacterial and QS inhibitor activities. The main constituent of ZOEO with percent composition above 6 % (α-curcumene, α-zingiberene, ß-sesquiphellandrene, and ß-bisabolene, α-citral, and α-farnesene) were exist in a very minimal percentage less than 0.7 % in Z. cassumunar. All major components of ZCEO with percentages higher than 5 % (terpinen-4-ol, sabinene, γ-terpinene) were present in low proportion (<1.18 %) in Z. officinale. ZCEO demonstrated moderate antibacterial activity against P. aeruginosa. The combination of ZCEO and tetracycline showed a synergistic effect (FICI of 0.5). ZCEO exhibited strong activity in inhibiting biofilm formation. ZCEO at 1 / 2 ${{ 1/2 }}$ MIC (62.5 µg/mL) was able to reduce pyoverdine, pyocyanin, and proteolytic activity. This is the first report on the activity of ZCEO in the inhibition of P. aeruginosa QS system and it may be used to control the pathogenicity of P. aeruginosa.

Hepatoprotective and toxicological evaluation of tropical Sargassum polycystum C. Agardh collected from Sumbawa coast Indonesia, against carbon tetrachloride-induced liver damage in rats.

Pharmacological activities of seaweed, including its antioxidant effect, have been demonstrated and can protect macromolecules from xenobiotic-induced damage. Understanding the potency of seaweed as a hepatoprotection and its toxicity remains underexplored. The aims of this study were to investigate the antioxidant and hepatoprotective activity, as well as the toxicological potencies of S. polycystum ethyl acetate extract against carbon tetrachloride-induced liver damage in rats. Total phenolic content and total flavonoid contents were quantified using standard spectroscopy-based methods. The antioxidant activity was measured using 1,1-Diphenyl- 2-picryl Hydrazil scavenging radical, while the composition of compounds was identified by LCMS/MS. After seven days of post-administrated rats with S. polycystum ethyl acetate extract, the serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvate transaminase (SGPT) levels were tested. Total phenolic content, total flavonoid content and IC50 of S. polycystum ethyl acetate extract were 1.28±0.04 of GAE/g, 13.32±0.48 QE/g and 744.726µg/mL, respectively. S. polycystum ethyl acetate extract 150mg/kg BW provides a hepatoprotective effect with a significant improvement in the levels of SGOT (134.845 U/l±9.645) and SGPT (60.238 U/l ± 9.645) (p<0.05). S. polycystum ethyl acetate extract potentially protected the damage induced by CCl4 in the rat's liver at a certain concentration, while a higher extract concentration requires further examination.