[Studies on flavonoids extraction technology from Glycyrrhiza inflata and their bacteriostatic activities].
OBJECTIVE
To study the extraction technique for the flavonoids from Glycyrrhiza inflata and their bacteriostatic bioactivities.


METHODS
It was investigated about comparison of extraction methods such as ultrasonic-assisted extraction (UAE), enzymatic extraction (EE), whisk extraction (WE) and repeat freeze-dissolve extraction (FDE). The UAE conditions were optimized by orthogonal array. The bacteriostatic effect was studied using doubling dilution.


RESULTS
The UAE was the most effective method and the optimal UAE conditions were adding 20-fold ethanol (30% v/v), extracting for two times, 20 min each time. Futhermore, the minimal inhibitory concentrations (MIC) of the flavonoids against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis were 0.03125, 0.03125, 0.125, 0.03125 mg/ml respectively.


CONCLUSIONS
UAE is suitable for fast and effective extraction of flavonoids. The flavonoids have obvious bacteriostatic bioactivities against microorganisms mentioned above.
Cui
Yong-Ming
YM
College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
Yu
Long-Jiang
LJ
Ao
Ming-Zhang
MZ
Yang
Ying
Y
Hu
Jing
J
D002480:Cellulase; D004365:Drugs, Chinese Herbal / Q000302:isolation & purification / Q000494:pharmacology; D004925:Escherichia / Q000187:drug effects*; D000431:Ethanol; D005419:Flavonoids / Q000302:isolation & purification* / Q000494:pharmacology*; D006035:Glycyrrhiza / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011208:Powders; D027343:Rhizome / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects; D013678:Technology, Pharmaceutical / Q000379:methods; D013997:Time Factors; D014465:Ultrasonics
D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D011208:Powders; D000431:Ethanol; D002480:Cellulase