Agronomic Evaluation and Chemical Characterization of Lavandula latifolia Medik. under the Semiarid Conditions of the Spanish Southeast.

Lavandula latifolia is one of the main rainfed crops of aromatic and medicinal plants produced in Spain. As a global concern, the agronomic productivity of this aromatic crop is also threatened by the consequences of imminent climate change. On this basis, the study of the agronomic production of two drought-tolerant ecotypes, after three years of cultivations practices, constitutes the main objective of the present study. For this trial, clones of the two pre-selected ecotypes, along with clones from two commercial plants (control), were grown in an experimental plot. The main results confirmed an increase in biomass and essential oil production with plant age. The essential oil chemotype defined by 1,8-cineol, linalool, and camphor was maintained over time, but a decrease in 1,8-cineol in the benefit of linalool was detected. In the phenolic profile, 14 components were identified, with salvianic acid and a rosmarinic acid derivate being the main compounds quantified. These phenolic extracts showed potent in vitro antioxidant capacity, and after the second year of cultivation practices, both phenolic compounds and antioxidant capacity remained stable. Thus, under semiarid conditions, L. latifolia drought-tolerant ecotypes reach a good level of production after the second year of crop establishment.

Biocidal Potential and Chemical Composition of Industrial Essential Oils from Hyssopus officinalis, Lavandula × intermedia var. Super, and Santolina chamaecyparissus.

This work presents the biocidal (insecticidal, ixodicidal, nematicidal, and phytotoxic) effects and chemical compositions of three essential oils obtained from the industrial steam distillation (IEOs) of hyssop (Hyssopus officinalis L.), lavandin (Lavandula × intermedia or L. × hybrida var. Super), and cotton lavender (Santolina chamaecyparissus L.). Their chemical composition analyzed by gas chromatography coupled to mass spectrometry showed 1,8-cineole (53%) and ß-pinene (16%) as the major components of H. officinalis, linalyl acetate (38%) and linalool (29%) of L. × intermedia; and 1,8-cineole (10%) and 8-methylene-3-oxatricyclo[5.2.0.02,4 ]nonane (8%) in S. chamaecyparissus. The biocidal tests showed that L. × intermedia IEO was the most active against the insect Spodoptera littoralis and toxic to the tick Hyalomma lusitanicum, IEO of H. officinalis was strongly active against S. littoralis, and finally, S. chamaecyparissus IEO was a strong antifeedant against the aphid Rhopalosiphum padi, toxic to H. lusitanicum and with moderate effects against Leptinotarsa decemlineata, S. littoralis, and Lolium perenne.

Emulsifying properties of acylated rapeseed (Brassica napus L.) peptides.

A peptide fraction having an average size of 5.6 amino acids has been purified from a rapeseed hydrolyzate, acylated using C(10)-C(14) acyl chlorides, and the surface tension values at the air-water interface and emulsifying properties studied. As compared with standard surface-active proteins, such as bovine serum albumin (BSA), and with detergents such as sodium dodecyl sulfate (SDS), acylated peptides exhibited particular surface characteristics. The surface tension at air-water interface of acylated peptides ranged from 29.1 to 37.8 mN/m at equilibrium; these values were considerably lower than those for BSA and closer those for SDS, suggesting that acylated peptides pack at the air-water interface more like detergents than like proteins. The adsorption of acylated peptides to the oil-water interface was slower than for SDS or BSA, as deduced from the rather large size of oil droplets in emulsions (31-17 microm). Consequently, these emulsions creamed extensively during aging. Nevertheless, emulsions generated from acylated peptides were in general more stable to phase separation than those prepared from SDS. The C(14) acylated peptides were more effective for generating emulsions than the C(10) and C(12) derivatives, especially concerning the stability of emulsions against coalescence and phase separation, which was better than SDS and close to BSA.