Chemical Composition and Antioxidant Activity of Essential Oil and Organic Extracts of Premna integrifolia Linn

ABSTRACT This study was designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and various extracts obtained from Premna integrifolia Linn. GC-MS analysis of the essential oil was resulted in determination 29 different compounds, representing 95.73% of total oil. Antioxidant activities of the essential oil and organic extracts of chloroform, ethyl acetate and methanol were determined by three different test systems namely DPPH (2,2-diphenyl-1-picrylhydrazyl), superoxide and nitric oxide radical scavenging assays. The essential oil and methanol extract showed potent antioxidant activity among all the tested samples. Furthermore, the amount of total phenolic compounds was determined and its content in methanol extract was the highest as compared to other samples. The results indicate that the essential oil and extracts of Premna integrifolia could serve as an important bio-resource of antioxidants for using in the pharmaceutical industries.

Antifungal potential of essential oil and ethanol extracts of Lonicera japonica Thunb. against dermatophytes.

The antifungal potential of essential oil and ethanolic leaf extracts of Lonicera japonica Thunb. was evaluated for controlling the growth of dermatophytes. The oil (1,000 ppm) and extracts (1,500 ppm) of L. japonica revealed 55.1-70.3 % and 40.1-65.5 % antidermatophytic effect against Microsporum canis KCTC 6348, 6349, 6591, Trichophyton rubrum KCTC 6345, 6352, 6375, Trichophyton mentagrophytes KCTC 6077 and 6085, respectively, along with their respective minimum inhibitory concentrations ranging from 62.5-500 and 125-1,000 µg/ml. Also, the oil had strong detrimental effect on spore germination of all the tested dermatophytes as well as concentration and time-dependent kinetic inhibition of M. canis KCTC 6348. The results demonstrated that L. japonica oil and extracts could be potential sources of natural fungicides to protect human and animals from fungal infections.

In vitro control of plant pathogenic Xanthomonas spp. using Poncirus trifoliata Rafin.

The secondary metabolites such as essential oil and pure compounds (limonin and imperatorin) from Poncirus trifoliata Rafin were tested for in vitro control of phytopathogenic bacteria of Xanthomonas spp. In vitro studies showed that the oil had inhibitory effect on Xanthomonas campestris pv. compestris KC94-17-XCC, Xanthomonas campestris pv. vesicatoria YK93-4-XCV, Xanthomonas oryzae pv. oryzae KX019-XCO and Xanthomonas sp. SK12 with their inhibition zones and minimum inhibitory concentration (MIC) values ranging from 13.1~22.1 mm and 62.5~125 µg/ml, respectively. Limonin and imperatorin also had in vitro antibacterial potential (MIC: 15.62~62.5 µg/ml) against all the tested Xanthomonas spp. Furthermore, the SEM studies demonstrated that limonin and imperatorin caused morphological changes of Xanthomonas sp. SK12 at the minimum inhibitory concentration (15.62 µg/ml). These results of this study support the possible use of essential oil and natural compounds from P. Trifoliata in agriculture and agro-industries to control plant pathogenic microorganisms.

Essential oil composition and antioxidant activities of Curcuma aromatica Salisb.

The chemical composition of the hydro-distilled essential oil from leaves of Curcuma aromatica Salisb. was analysed by GC-MS. Twenty-three compounds representing 94.29% of the total oil were identified. The antioxidant activities of the oil and various extracts of C. aromatica were evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical-scavenging assays. The oil and methanol extract showed potent DPPH radical-scavenging activities (IC(50)=14.45 and 16.58 microg/ml, respectively), which were higher than butylated hydroxyanisole (IC(50)=18.27 microg/ml). The extracts also exhibited remarkable superoxide radical-scavenging activities (IC(50)=22.6-45.27 microg/ml) and the activity in the methanol extract was superior to all other extracts (IC(50)=22.6 microg/ml). Furthermore, the amount of total phenolic compounds was determined and its content in ethyl acetate extract was the highest as compared to other extracts. The results indicate that the oil and extracts of C. aromatica could serve as an important bio-resource of antioxidants for using in the food industries.

Hair growth promoting effect of Zizyphus jujuba essential oil.

This study was undertaken to examine the efficacy of essential oil from seeds of Zizyphus jujuba for its potential role on hair growth by in vivo method. Essential oil was applied at different concentrations (0.1%, 1% and 10%) over the shaved skin onto the backs of BALB/c mice and monitored for 21 days. After 21 days, mice treated with 1% and 10% of oil produced a greater effect on the length of hair which were measured to be 9.96 and 10.02 mm, respectively, as compared to the control (8.94 mm). We measured the weight of hair/cm(2) area of dorsal skin and also evaluated hair thickness and hair follicles microscopically after plucking the hair immediately from the shaved area of mice and found the best results for 1% of essential oil-treated mice. From this study, it is concluded that Z. jujuba essential oil possesses hair growth promoting activity.

Antimicrobial and cytotoxic constituents from leaves of Sapium baccatum.

Six compounds, namely, Lupeol (1), Betulin (2), beta-Taraxerol (3), Taraxerone (4), Stigmasterol (5) and beta-Sitosterol (6) were isolated from the petroleum ether extract of the leaves of Sapium baccatum based on spectroscopic evidence. Lupeol (1), Betulin (2) and Stigmasterol (5) were isolated for the first time from this plant. The cytotoxic potential of the different solvent extracts (methanol, petroleum ether, carbon-tetrachloride and dichloromethane); six column fractions (F-4, F-7, F-10, F-12, F-18 and F-22) of petroleum ether extract and three pure compounds 1, 4 and 6 were determined by using brine shrimp lethality bioassay. The LC50 of all the tested samples were showed to be lethal to brine shrimp nauplii. However, petroleum ether, carbon-tetrachloride extract, column fractions F-4 and F-18 of petroleum ether extract and pure compound 6 showed quite potent activity in brine shrimp lethality bioassay with LC50 1.33, 1.35, 1.40, 1.58 and 1.58 microg/ml, respectively. These result suggested that they might be contain antitumor or pesticidal activity. Further, the methanol extract and four column fractions (F-7, F-12, F-18 and F-22) of petroleum ether showed significant activity against the tested microorganisms.

Anti-inflammatory activity of seed essential oil from Zizyphus jujuba.

This study was undertaken to evaluate the effect of essential oil from seeds of Zizyphus jujuba on TPA-induced skin inflammation in experimental mice. Exposure of TPA on the ear of the BALB/c mice caused a marked increase in both ear thickness and skin water content. The ear thickness was measured for TPA-induced ear was 0.54 mm, as compared to control (0.23 mm). Treatment with 1% and 10% of essential oil caused significant decrease in ear thicknesses which were measured to be 0.30 and 0.35 mm, as well as reduce the water content about 51% and 53% in the TPA-induced skin inflammation model, respectively. Furthermore, histological analysis clearly confirmed that Z. jujuba essential oil inhibited the inflammatory responses of skin inflammation in animal model. Therefore, our findings demonstrate that the essential oil of Z. jujuba seeds might accelerate the development of new drugs for various inflammatory diseases.

Antioxidant and antilisterial effect of seed essential oil and organic extracts from Zizyphus jujuba.

Hydrodistilled volatile oil from the seeds of Zizyphus jujuba was analyzed by GC-MS. Twenty three compounds representing 91.59% of the total oil was identified. The oil and organic extracts revealed a great potential of antilisterial effect against all five strains of Listeria monocytogenes ATCC 19111, 19116, 19118, 19166 and 15313. Also the oil had strong detrimental effect on the viable count of the tested bacteria. The samples were also subjected to screening for the antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals scavenging activities assay. In the first case, the IC(50) value of the Z. jujuba essential oil was determined to be 5.21+/-0.01 microg/ml. Among the extracts, the strongest activity was exhibited by the methanol extract with an IC(50) value of 20.44+/-0.18 microg/ml. In the superoxide radicals scavenging activities assay, methanol extract was superior to all other extracts (IC(50)=18.60+/-0.3 microg/ml). Furthermore, the amount of total phenolic compounds was determined. The results indicate that the essential oil and extracts of Z. jujuba could serve as natural antimicrobial and antioxidant agents for the food industry.

Chemical composition, antibacterial and antioxidant activities of leaf essential oil and extracts of Metasequioa glyptostroboides Miki ex Hu.

The aims of this study were to analyze the chemical composition of leaf essential oil of Metasequioa glyptostroboides Miki, and to test the efficacy of oil and extracts (hexane, chloroform, ethyl acetate and methanol) against food spoilage and food-borne pathogenic bacteria and their antioxidant activity. The GC-MS analysis revealed 49 compounds representing 94.62% of the total oil containing 2-butaneone (30.6%), cyclopentane (15.1%), beta-myrcene (13.29%), cyclobutane (7.67%), furan (3%), valeramide (2.81%), borneol (1.2%), beta-farnesene (1.67%), thymol (1.44%) and alpha-pinene (1.46%) as major components. The oil (1000 microg/disc), and extracts (1500 microg/disc) exhibited promising antibacterial effect as a diameter of zones of inhibition (10-18 and 7-13 mm), respectively. MIC values of oil and the extracts were ranged 125-2000 and 250 to <2000 microg/ml, respectively. Also the oil had strong antibacterial effect on the viable counts. Scanning electron microscopic study demonstrated potential detrimental effect of the oil on the morphology of S. aureus KCTC1916. The free radical scavenging activities of the oil and ethyl acetate extract were found to be 11.32 and 19.12 microg/ml, respectively. Also the ethyl acetate extract revealed the highest phenolic contents (85.17 mg/g of dry wt) as compared to the other extracts.