Chemical Composition and in Vitro Evaluation of the Antioxidant and Antimicrobial Activities of Eucalyptus gillii Essential Oil and Extracts

In this study, essential oil and various extracts (hexane, petroleum ether, acetone, ethanol, methanol and water) of Eucalyptus gilii were screened for their chemical composition, antimicrobial and antioxidant activities. The essential oil chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID), respectively. Thirty four compounds were identified, corresponding to 99.5% of the total essential oil. Tannins [104.9-251.3 g catechin equivalent (CE)/Kg dry mass], flavonoids [3.3-34.3 g quercetin equivalent (QE)/Kg dry mass], phenolics [4.7-216.6 g gallic acid equivalent (GAE)/Kg dry mass] and anthocyannins [1.2-45.3 mg cyanidin-3-glucoside equivalent (C3GE)/Kg dry mass] of various extracts were investigated. Free radical scavenging capacity of all samples was determinedt. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, the IC50 of essential oil was 163.5 ± 10.7 mg/L and in the 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate (ABTS) assay, it was 94.7 ± 7.1 mg/L. Among the various extracts, the water extract showed the best result (IC50 = 11.4 ± 0.6 mg/L) in the DPPH assay which was comparable to vitamin C (IC50 = 4.4 ± 0.2 mg/L). The antimicrobial activities were evaluated against different bacterial and fungal strains. Gram positive bacteria were found to be more sensitive to the essential oil and extracts than Gram negative ones. Anthocyanins seem to have a major effect on the growth of Bacillus subtilis (R2 = 0.79). A significant antifungal activity was observed against the yeast and fungi. Correlations between chemical composition and antioxidant activities were studied and R2 values were about 0.96 for the effect of phenolics on the DPPH assay

Eucalyptus oleosa Essential Oils: Chemical Composition and Antimicrobial and Antioxidant Activities of the Oils from Different Plant Parts (Stems, Leaves, Flowers and Fruits)

Essential oils obtained by hydrodistillation from the different parts (stems, adult leaves, immature flowers and fruits) of Eucalyptus oleosa were screened for their antioxidant and antimicrobial properties and their chemical composition. According to GC-FID and GC-MS, the principal compound of the stem, immature flowers and the fruit oils was 1,8-cineole, representing 31.5%, 47.0% and 29.1%, respectively. Spathulenol (16.1%) and γ-eudesmol (15.0%) were the two principal compounds of adult leaves oil. In the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, the oils of the four parts showed moderate antioxidant activity. In the ABTS (2,2’-azinobis-3-ethylbenzothiazoline-6-sulphonate) assay, the most active part was the adult leaves, with a IC50 value 13.0 ± 0.6 mg/L, followed by stems (IC50 = 43.5 ± 1.4 mg/L). The essential oils showed a better antibacterial activity against Gram-positive and Gram-negative bacteria, and a significant antifungal activity also was observed against yeast-like fungi. A strong correlations between oxygenated monoterpenes and antimicrobial activity (especially 1,8-cineole) were noted (R2 = 0.99, 0.97 and 0.79 for B. subtilis, P. aeruginosa and C. albicans, respectively)

On class and elitism in archaeology

While archaeology is certainly a politically conscious discipline, with various members involved in political and activist movements, especially focusing on gender and race issues, little has been said, discussed, or done with regards to class and elitism. In fact, it seems that since the advent of postmodernity in the 1970s, class and elitism have become moot topics. The aim of this article is to reflect upon class-based discrimination and elitism in archaeology, first by tracing the changes they have undergone, especially during late capitalist times, and how class has become sublimated to fit the neoliberal agenda; second, the article focuses on several issues concerning class and elitism in the university context in general, and in archaeology in particular, and how these serve as barriers to those less wealthy and fortunate; third, this work highlights how these issues concerning class and elitism in archaeology then affect scientific discourse on one hand, which has become more technologically advanced, and consequently more expensive, and archaeological theory on the other, which in its hectic search for novelty has lost its capacity to truly contribute anything new to our understanding of past and present societies

Eucalyptus camaldulensis: Volatiles from immature flowers and high production of 1,8-cineole and β-pinene by in vitro cultures

Calli of Eucalyptus camaldulensis Dehn were induced, for the first time, from immature flowers and stamens and established in the presence of 2,4-D and BA, under dark and light conditions. Immature flowers, of the same type used for callus induction, were submitted to hydrodistillation while the induced calli were extracted with n-pentane. The constituents of the n-pentane extracts and of the hydrodistillate were identified by GC-MS. The main constituents of the hydrodistillate from immature flowers were 1,8-cineole (34.7%), β-pinene (7.7%), and spathulenol (9.5%). The n-pentane extract from calli developed from stamens consisted only of alkanes, alkenes and alcohols, while that of calli developed from immature flowers consisted mainly of monoterpenes (92.08-96.56%). The main monoterpenes produced in these calli, cultured in darkness and under light conditions, were 1,8-cineole, 62.70 and 69.26% as well as β-pinene, 27.09 and the 25.31%, respectively. © 2001 Elsevier Science Ltd. All rights reserved

Eucalyptus camaldulensis: Volatiles from immature flowers and high production of 1,8-cineole and β-pinene by in vitro cultures

Calli of Eucalyptus camaldulensis Dehn were induced, for the first time, from immature flowers and stamens and established in the presence of 2,4-D and BA, under dark and light conditions. Immature flowers, of the same type used for callus induction, were submitted to hydrodistillation while the induced calli were extracted with n-pentane. The constituents of the n-pentane extracts and of the hydrodistillate were identified by GC-MS. The main constituents of the hydrodistillate from immature flowers were 1,8-cineole (34.7%), β-pinene (7.7%), and spathulenol (9.5%). The n-pentane extract from calli developed from stamens consisted only of alkanes, alkenes and alcohols, while that of calli developed from immature flowers consisted mainly of monoterpenes (92.08-96.56%). The main monoterpenes produced in these calli, cultured in darkness and under light conditions, were 1,8-cineole, 62.70 and 69.26% as well as β-pinene, 27.09 and the 25.31%, respectively. © 2001 Elsevier Science Ltd. All rights reserved