Muriel Cerny

Aframomum stipulatum (Gagnep) K. Schum and Aframomum giganteum (Oliv. & Hanb) K. Schum as Aroma Tincto Oleo Crops resources: essential oil, fatty acids, sterols, tocopherols, and tocotrienols composition of different fruit parts of Congo varieties

BACKGROUND Today, few known plant species provide both an essential oil (EO) and a vegetable oil (VO). Seed and husk of two Aframomum species were investigated and compared in terms of EO, fatty acids, tocopherols, and tocotrienols. RESULTS EO yield reaches 15.3 g kg(-1) in the seeds and 3.2 g kg(-1) in the husks, while VO yield is 180.0 g kg(-1) in the seeds and 25.0 g kg(-1) in the husks. β-Pinene, 1,8-cineol, α-selinene, terpine-4-ol, linalool, myrtenal and β-caryophyllene are the major compounds of seed and husk EO. Fatty acid analysis of two Aframomum species shows that oleic, linoleic, and palmitic acids were the major compounds of VO. Total sterol contents reached 4.3 g kg(-1) in seed VO and 8.5 g kg(-1) in husk VO. An appreciable amount of tocopherols (0.52 g kg(-1) ) was found in seed VO. CONCLUSION The seed and husk oil of A. stipulatum and A. giganteum fruits are rich sources of many bioactive constituents such as fatty acids, sterols, tocopherols and tocotrienols. These tropical wild fruits can be considered as new Aroma Tincto Oleo Crops (ATOC) resources that contain both EOs and VOs.

Effect of methylene blue on the formation of oxidized phospholipid vesicles

Soybean phosphatidylcholine, which is rich in linoleic acid, was oxidized with singlet oxygen through photosensitization with methylene blue. This compound facilitates the oxidation of phospholipids relative to the reaction with free unsaturated fatty acids. A response surface methodology was used to control oxidation, with methylene blue concentration and the amount of available air as independent variables. The conjugated diene-to triene ratio was then monitored. Hydroperoxide yield dependent principally on the amount of air, whereas photosensitizer concentration strongly influenced the size and zeta potential of vesicles formed by the sonication of oxidized phospholipids in water. Methylene blue plays an important role in the surface charge expression and ion permeability of these vesicles.