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. A B R A~~O V I T C I~ AND 0. A. KOLEOSO 'The extractives from the heartwood of Popz~lus trernz~lozdes (aspen poplar) have been the subject of a systematic investigation (1-3). I t was shown that saponification of the acetone extractives gave a steam-volatile portion which could be resolved into four major components by gas-phase chromatography (1). I t has since been established that one of the major coinponents of this mixture was isophorone, which was an artifact formed during the extraction procedure. We now report a study of the composition of the steam-volatile fraction of the benzene extractives of the heart~vood, from which fatty acids had been removed \vith sodium bicarbonate.The mixture was subjected to a preliminary preparative gas chromatographic separation to give nine components, the first four of .which were collected together as fraction I and later rechromatographed. T h e other pealts were collected individually as fractions 11, 111, IV, V, and VI, respectively (increasing retention times). Fractions IV and VI appeared to be inixtures which could not be resolved further and xere not examined a t this time.Fractions 11, 111, and V were rechromatographed on Apiezon L columns; I1 and V were single con~pounds, and I11 was resolved into four fractions: IIIA, IIIB, I I I C , and 111".Colnpound I1 had bands in the infrared characteristic of a primary alcoholic group and a monosubstituted phenyl ring. Its nuclear nlagnetic resonance (n.1n.r.) spectrum exhibited a 51-1 singlet a t T 2.9 and a 2H singlet a t T 5.7, suggesting that i t \!-as benzyl alcohol, \vhich was confirmed by conlparison of the spectra tvith those of an authentic sample. Similarly, compound I I I A was shown to be phenol, and compound IIIB 0-phenylethanol. Compound I I I C exhibited a weak band a t 3 500 cin-I (OH), a band of inedium intensity a t 2 720 cm-I 0 I I (C-W), and a strong band a t 1 GSO cm-I, suggesting the presence of an a,@-unsaturated aldehyde function. I t had an ultraviolet absorption maximuin a t 274 nip, suggestive of an aor 0-hydroxy-a$-unsaturated aldehyde (4). I t formed a 2,4-dinitropl~enylhydrazone and a semicarhazone, the melting points of which were very close to those of the corresponding derivatives of isophorone. T h e infrared and ultraviolet spectra of IIIC, hen-ever, \\-ere quite different from those of isophorone. Unfortunately, there were insufficient amounts of I I I C to carry out anj7 further structural studies. Compound V had bands in the infrared characteristic of a phenolic hydroxyl group and a para-disubstituted benzene ring. I t s n.1n.r. spectrum showed a 41-1 quartet a t T 3.2, a 2H quartet a t T 7.5 (Ar-CB2-), and a 31-1 triplet a t T 8.9 (-CI-12-Cf13).These data \Irere compatible with the compound being p-ethylp1~enol ; this was confirmed by direct comparison with an authentic sample.Fraction I was rechromatographed a t a lower temperature and resolved into nine cornponents (fractions 1"-1'). Fractions I", ID, I", and I' were collected, since they were the most abundant (the first fracti...

Sorghum and maize are two of the major food grains grown and eaten in Nigeria. Production of these two crops averages about 4.5 million metric tons, this value representing approximately 56% of the total cereal grains produced in Nigeria for the past three years.Although the production of these cereals has increased over the years, the effect has not been felt because of inadequate post-harvest technology especially in the area of processing. Maize and sorghum processing in Nigeria as in many other African countries is still by the traditional method of pounding in a mortar and winnowing. This method is usually performed by women, and is the major occupation for many of them. It is time consuming in that less than 2 kg of flour/hour/woman at an extraction rate of about 60% can be produced. The flour produced normally has a moisture content of 2 5 4 0 % and with the rather hot climate the keeping quality is usually poor. The efforts being made through research and development to improve milling efficiency, increase the quantity of available cereal products, increase the shelf-life and eventual diversification of processed grains to replace fully or partially imported cereals for domestic and industrial uses are discussed.

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