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Subcritical water extraction (SWE) of monoterpenes from coriander seeds and effect of extraction conditions were investigated varying temperature (170–200 °C) and time (5–20 min). Monoterpenes was influenced by differences in their chemical structures and SWE conditions. The extraction efficiency of linalool was decreased with the increasing extraction temperature and extraction time, whereas linalool oxide was increased due to conversion of linalool to linalool oxide by hydrothermal oxidation. Geraniol, which has the same chemical formula as linalool, was extracted at a high temperature (170 °C) owing to the different placement of hydroxyl groups. The efficiency of SWE for geraniol (1.22 ± 0.22 mg/g) and linalool oxide (0.30 ± 0.09 mg/g) was higher than that of conventional extraction methods (hexane, methanol, hot water, and hydrodistillation). Therefore, SWE can be used to effectively and selectively extract monoterpenes by exploiting temperature changes in short extraction time. [Display omitted] • Monoterpenes were efficiently selectively extracted using subcritical water extraction. • Major compounds extracted were oxygenated monoterpenes in subcritical water. • Linalool converted to linalool oxide under subcritical-water condition above 170 °C. • Monoterpene contents by SWE were higher than conventional extraction methods. [ABSTRACT FROM AUTHOR]

Abstract: Linalool oxide is a monoterpene that is found in some species of aromatic plants. The effects of the inhalation of linalool oxide (0.65%, 1.25%, 2.5% and 5.0% w/w) in the elevated plus-maze and light/dark box tests as animal models of anxiety were investigated in adult male mice and compared with the effects of the reference anxiolytic diazepam (0.5 and 2.0mg/kg), administered intraperitoneally. Additionally, the effects of inhaled linalool oxide were investigated in the rotarod test. Linalool oxide significantly increased the number of visits to the open arms of the elevated plus-maze and the amount of time spent there as well as the total number of entries. In the light/dark box test, inhalation of linalool oxide led to an increase in the time spent by the mice in the brightly-lit chamber and in the number of times the animal crossed from one compartment to another. Performance on the rotarod was unaffected. Thus, inhaled linalool oxide was found to have anxiolytic properties in both animal models, without causing any motor deficit. These results suggest that inhalation of linalool oxide may be a useful means of counteracting anxiety. [Copyright &y& Elsevier]

• A significant correlation occurred between linalool and tea leaf area. • There was no significant relation between linalool synthesis and leaf area in tea. • Metabolism of linalool affected differential accumulation of linalool in tea. • The larger tea leaves were less capable of conversion of linalool to linalool oxides. It is generally proposed that tea cultivars with larger leaves contain more linalool, an important tea aroma contributor, than ones with smaller leaves. The objective of this study was to confirm the trait and explore the involved reason. Investigation on ten tea cultivars with different leaf areas demonstrated a significant positive correlation between linalool content and leaf area (R2 = 0.739, p = 0.010). Analysis of metabolite and gene expression level showed that the transform ability of linalool into linalool oxides was the key factor. Feeding experiments that supplied tea leaves of different leaf areas with [2H 3 ]linalool under different light conditions revealed that the larger tea leaves receive more light and are less capable of transformation of linalool to linalool oxides, thus leading to linalool accumulation. This information will advance understanding of the variation of linalool content in tea varieties and will provide assistance in breeding and screening of high-linalool tea cultivars. [ABSTRACT FROM AUTHOR]

• Improved surveillance of Aedes aegypti can be achieved using host-derived attractants from plant or human sources. • Linalool oxide (LO) and hexanoic acid (HA) representing plant- and human-derived odorants, respectively, increase trap catches of Ae. aegypti in the presence of CO 2. • Blends of LO and HA masked the attractive effective of each other resulting in decreased Ae. aegypti catches. Linalool oxide (LO) and hexanoic acid (HA) represent plant- and human-derived odorants, respectively, previously found as attractants for the dengue vector Aedes aegypti. Here, we investigated if a blend of both compounds can improve captures of this mosquito species in field trials in two dengue endemic sites, Kilifi and Busia Counties in Kenya. Ae. aegypti captures were significantly higher in Kilifi than Busia (χ 2 1,142 = 170.63, P < 0.0001) and varied by treatments (χ 2 5,137 = 151.19, P = 0.002). We found that CO 2 -baited BG Sentinel traps combined with a blend of both odorants decreased Ae. aegypti captures about 2- to 4-fold compared to captures with the individual compounds (LO or HA) used as positive controls. This was the case for all blends of LO and HA, irrespective of the doses tested. Our findings indicate that combining plant- and human-derived odors may elicit a masking effect in trapping Ae. aegypti. These results partly corroborate previous findings for malaria mosquitoes which showed that combining lures from both host sources either decreases or increases trap catches depending on the dose. Further investigations in the usefulness of combining plant and animal odorants in mosquito trapping are therefore necessary. Image, graphical abstract [ABSTRACT FROM AUTHOR]