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A synthetic blend of the aggregation pheromone [(3R,4S,1'E)-3,4-bis(1'-butenyl)tetrahydro-2-furanol, linalool, farnesol, and nerolidol] of the spined citrus bug,Biprorulus bibax, and the pentatomid defense chemical, (E)-2-hexenal, both attracted adultB. bibax to individual trees in citrus orchards. Lemon trees containing single glass vials with aggregation pheromone or (E)-2-hexenal were colonized by significantly greater numbers of reproductiveB. bibax than unbaited trees. There was no significant difference between the treatments and bug recruitment was not improved by using both treatments.B. bibax did not enter cylinder/funnel traps baited with aggregation pheromone but colonized trees containing the traps. Orange or lemon trees containing aggregation pheromone on orchard perimeters recruited significantly larger populations of emigrating, nonreproductiveB. bibax during fall than untreated trees. Nonreproductive bugs were not attracted to trees containing (E)-2-hexenal. The potential for using these semiochemicals as management tools forB. bibax is discussed.

In order to overcome the limitations of the methodology for the separation of enantiomers in GLC analysis, we successfully developed a novel GLC column named 'Chiramix', coated with a mixture of two chiral stationary phases, heptakis-(2,6-di-O-methyl-3-O-pentyl)-ˇ-cyclodextrin (2,6-Me-3-Pe-ˇ-CD) and octakis-(2,6-di-O-methyl-3-O-trifluoroacetyl)--cyclodextrin (2,6-Me-3-TFAc--CD). It was proved that the 'Chiramix' column is greatly superior to those with a single chiral phase for separating enantiomers of compounds with various functional groups. As a successful example, this was applied to the analysis of multicomponent systems, such as peach flavours, and the enantiomeric purities of several components of monoterpene hydrocarbons, alcohols, ketones and lactones were determined exactly and simultaneously.

Four isomers of acetoxycineoles, (trans and cis)-2- and 3-acetoxy-1,8-cineoles, were identified as the odorous components of the rhizomes of greater galangal. Their structures were confirmed by comparing the retention indices by GC and the mass spectra with those of synthesized compounds. The concentration of trans-3-acetoxy-1,8-cineole was the highest among the isomers. The isomers presented individual odor features:  the (trans and cis)-2 isomers respectively exhibited woody and sweet aromas, while the (trans and cis)-3 isomers respectively showed sweet floral and camphoraceous aromas. Of these, trans-2-acetoxy-1,8-cineole seemed to have the strongest qualitative effect on the characteristic flavor of greater galangal. Keywords: Alpinia galanga Willd.; greater galangal; rhizome; flavor component; trans-2-acetoxy-1,8-cineole; cis-2-acetoxy-1,8-cineole; trans-3-acetoxy-1,8-cineole; cis-3-acetoxy-1,8-cineole

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