| Summary: | 碩士 === 弘光科技大學 === 生物科技研究所 === 97 === Red and green Perilla frutescens leaves were examined for their antioxidant antibacterial, and anti-inflammatory bioactivities. Essential oils (EO) were first separated by the steam distillation. The obtained EO were further subjected to solvent fractionation on a silica gel chromatorgraphy. The separated sub EO fractions were analyzed by GC/MS.
The yields of the essential oil were 0.04% and 0.03% for the red and green leaves of Perilla frutescens, respectively. Fourty kinds of volatiles were found in the essential oil of red Perilla frutescens, among which the major components were perilla aldehyde and limonene, reaching respectively 54.35% and 23.81% in the whole essential oils. On fractionation with pentane, trans-caryopnyllene was found to be the major chemical and reached a content of 38.94%. While the ether layer contained 93.19% of perilla aldehyde. Fourty three kinds of volatiles were found in the essential oil of green Perilla frutescens, perilla aldehyde and limonene, the major two constituents, were found to reach 65.26 and 12.49%, respectively. The corresponding pentane layer contained 41.96% of trans-caryopnyllene, and the ether layer 84.40% of perilla aldehyde.
By antioxidant analysis, the aqueous extract of red leaves at concentration of 5mg/mL showed 64.52% of DPPH free radical scavenging capability.In contrast, the aqueous extract of green leaves at the same concentration exhibited a 34.87% of Fe2+-chelating capability. Its ether fractioante at 0.5 mg/mL showed a 56.52% of SOD scavenging capability. In contrast, the ether extract of red leaves exhibited a 56.12% H2O2 cleavage capability.
The total polyphenolics were analyzed. Data showed that each 100g of the red/green leaves contained a total poplyphenolics of 578.49/614.02mg. The content of rutin and quercetin reached 20.44/13.92mg and
77.41/29.65mgrespectively.
By antibacterial analysis, we recognized that the crude essential oil at 0.1% revealed 70% of antibacterial properties. On a chromatographic separation, the ether fractionate attained a 95% of antibacterial activity against the common pathogens E. coli, S. aureus, V.parahaemolyticus, and S. typhimurium, while only 85% effective against the strain T. mentagrophytes, comparing to the better effect of the essential oil of green leaves in inhibition of H. pylori.
By anti-inflammatory analysis, we showed that all the aqueous extracts of red and green leaves revealed substantial effect to suppress the expression of TNF-α, and indeed more potent than the ethanol extracts. In contrast, the extracts of red leaves possessed better anti-inflammatory bioactivity.
In conclusion, Perilla frutescens leaves, despite the red or green, have the merit to provide moderate anti-oxidants, anti-bacterial and anti-inflammatory capability.
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