The Influence of Essential Oils on Human Vigilance

Olfactory stimuli are used in aromatherapy to enhance mood, well-being and work efficiency. Nevertheless, the impact of fragrances on cognitive performance in humans is not well understood. The present investigation aimed to evaluate the effects of 1,8-cineol, jasmine absolute ether, linalyl acetate and peppermint essential oil on human vigilance performance. The odorants were administered by means of inhalation and, except for peppermint essential oil, were tested at 2 different dosages. Performance in a standard visual vigilance task was measured in terms of speed and accuracy and subjective ratings of the odorants were assessed in terms of pleasantness, intensity, arousal and stress. We hypothesized that 1,8-cineol, jasmine absolute ether and peppermint essential oil would improve vigilance performance, whereas linalyl acetate would impair such performance. Comparison of the performances of the seven independent experimental groups with that of a control group did not show any of the expected effects. In contrast, inhalation of linalyl acetate decreased reaction times. Within-group analyses, however, revealed significant interactions between subjective ratings of the odorants and task performance. The results of the present investigation emphasize the high impact of subjective factors on the modulation of attentional functions by olfactory stimuli in humans.

Effect of Securigera Securidaca Linnaeus on Conditioned Avoidance in Mice

6 groups of albino mice ( ns = 6) were administered finely crushed Securigera Securidaca or its extracts. 3 groups of animals were given chloroform, absolute ether, or petroleum ether extract of seeds of Securigera Securidaca. The dose for each extract was 100 mg/kg body weight. Two groups of animals were given 100 mg/kg or 250 mg/kg body weight of crushed seeds. The control group of animals was given olive oil 10 cc/kg body weight. All the doses of the drugs were given orally. The conditioned avoidance technique was used 2 and 4 hr. after every treatment to test Ss' learning. Analysis of variance showed significant differences for treatments, days of treatments, and animals within time and treatment. Also a significant time-day interaction indicated the differential effect of time on different days.

Effect of Securigera Securidaca on Electroshock Seizure Threshold in Mice

Finely crushed seeds 100 mg/kg or 250 mg/kg of body weight of Securigera Securidaca or their extracts with petroleum ether, absolute ether or chloroform 100 mg/kg of body weight were administered to albino mice to study their effects on brain excitability. The drugs significantly increased minimal electroshock-brain seizure-threshold. This effect might be due to increase the brain concentration of γ-aminoburyric acid.

THE CONVERSION OF META- AND PARA-SUBSTITUTED BENZALDOXIME ARENESULFONATES TO NITRILES

The meta- and para-substituted syn-benzaldoxime arenesulfonates were prepared from the reaction between the sodium salt of the oxime and the acid chloride in absolute ether. These oxime esters reacted in aqueous alcohol readily to yield the corresponding nitriles exclusively. The reaction rates can be correlated by a Hammett plot with a slope of −0.77. Several para-substituents tended to deviate from the line. Isotope study gives a kH/kD ratio of 4.51. The rate was found to be sensitive to the change in the ionizing power of the solvent, and to the change in the strength of the esterifying acid. The addition of lithium perchlorate gives rise to a normal salt effect. Sodium acetate brings about a basic elimination having a Hammett p value of + 0.44. A mechanism is proposed in the light of these results.

THE ACTION OF ZINC ON α,β-DIBROMOPROPIONYL HALIDES

A vigorous reaction occurs between zinc filings and a solution of α,β-dibromopropionyl bromide in absolute ether. The principal organic products of the reaction are ethyl acrylate and ethyl bromide. Suggested steps in the reaction are described. The α,β-dibromopropionic acid from which the acid halides were made was obtained by oxidation of β,γ-dibromopropyl alcohol. Treatment of β-bromopropionic acid in the Hell–Volhard–Zelinsky reaction failed to accomplish bromination in the α-position, only β-bromopropionyl bromide being isolated.