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Cinnamylpyrogallol was found to be a greater inhibitor of fungal growth than either cinnamyl alcohol or pyrogallol. Antifungal activity decreased with time owing to oxidation of the compound in solution. Cinnamylphloroglucinol was less active than cinnamylpyrogallol against the 27 species of fungi (including dermatophytes) tested. In addition these substances also were active against two of the four bacterial species tested.

Positive patch test reactions to Frullania nisquallensis were observed in seven forest workers who had allergic contact dermatitis. Frullania is a genus of leafy liverworts. Five of these seven patients also showed coincidental positive patch test reactions to usnic acid derived from lichenized fungi. Attacks of such dermatitis occurred only during work in forest areas, were worse in wet weather, appeared within a day or two of starting work amongst vegetation, and subsided in two to four weeks after leaving work. "Cedarpoisoning" is a misnomer for allergic contact dermatitis occurring in forest workers in British Columbia; such dermatitis results from exposure to species of epiphytes on trees.

The effects of light on growth, pigmentation and the activities of enzymes involved in the deamination of phenylalanine and tyrosine and in the biosynthesis of hispidin were examined in Polyporus hispidus. Evidence is presented for the stimulation of phenylalanine ammonia-lyase activity by light. Tyrosine ammonia-lyase activity and aminotransferase activities for phenylalanine and tyrosine were higher in the dark. Tracer studies showed that conversion of cinnamate into p-coumarate is enhanced by light. p-Coumaric acid hydroxylase, catalysing the conversion of p-coumarate into caffeate, could be detected only in cultures exposed to light. These results suggest that the cinnamate pathway for the metabolism of phenylalanine, leading to hispidin synthesis, is regulated by light in P. hispidus.

We have isolated two dithiapolyacetylenes from the roots of Chaenactis douglasii and from the plant roots as well as root cultures of Eriophyllum lanatum , namely 1-(2-methylethyn)-4-(hex-1,3-diyn-4-ene)-2,3-dithiacyclohexa-4,6-diene, and 1-(4-methylbut-1,3-diyn)-4-(but-1-yn-3-ene)-2,3-dithiacyclohexa-4,6-diene. We propose the trivial names thiarubrine A and thiarubrine B for these compounds.

Phenylalanine ammonia-lyase (PAL) has been detected in an Ascomycete, Nectria cinnabarina. Growth in light increases levels of PAL in some but not all Basidiomycetes.

E/Z Photoisomerism, in UV-A, of cell wall ferulate and diferulate-carbohydrate esters is suggested as a mechanism for transduction of light energy leading to changes in wall structure and hence water flux, turgor pressure and growth. Unilateral light would cause phototropism.

Eleven sesquiterpenes have been examined as potential moleuscicides against the planorbid snail Biomphalaria havanensis . The most potent compound was helenalin followed by pyrethrosin.

Cinnamic acid 4-hydroxylase from potato tuber tissue does not appear to be stimulated by light, but only by the wounding of the tissue. This behavior is in contrast to that observed in other tissues.

HIGHER plants are capable of synthesizing aromatic compounds from shikimic acid, possibly through a pathway similar to that described by Davis et al. 1. Certain benzene rings, however, are formed from acetate in accordance with the hypothesis of Birch and Donovan2. Thus the B ring of quercitin is synthesized from shikimic acid3 whereas the A ring is an acetate-formed ring4.

Phylloglossum drummondii, Kunze is a small and relatively rare cryptogam of New Zealand and Australia. It is considered to be a lycopod which is reduced and specialized in the adoption of a geophytic habit1. So far as we know, it has not been examined for any of its organic chemical constituents.

DURING the course of a study of glyoxylic acid metabolism in wheat it became desirable to obtain glyoxylate labelled with carbon-14, a compound which does not appear to be available commercially. Oxalic acid, which is available commercially as oxalic acid-14C, has been used in the synthesis of glyoxylic acid1–4. Weinhouse and Friedmann5 synthesized glyoxylate-14C from oxalate-14C by reduction with mercuric chloride and Grignard magnesium. In order to isolate the crystalline bisulphite addition product of glyoxylate it was necessary to dilute the oxalate-14C (2.25 mgm.) with 900 mgm. of inactive oxalate. Tafel and co-workers3,4 introduced an electrolytic method for the reduction of oxalate to glyoxylate. These workers used relatively large amounts of oxalate (10 gm.) and obtained very high yields (87 per cent). The reaction was carried out in 10 per cent sulphuric acid at 10° C. with a current of 4 amp. and was complete in 30 min. Mohrschulz2 investigated the reaction more thoroughly and showed that it could be carried out in 2 per cent sulphuric acid at a temperature of 15–20° C. The highest yields were obtained using mercury as the cathode (rather than lead, copper or nickel).

MALEIC hydrazide is widely used as a growth inhibitor in plants. Its activity as a plant growth regulating substance was described so long ago as 19491 and it is used to arrest sprouting in stored root crops, for the temporary inhibition of growth of lawn grass and hedges and for the prevention of the formation of suckers in tobacco. It is translocatable in plants and is toxic to meristematic tissue causing a loss of apical dominance2. Little seems to be known about the fate of this compound in plants, or the mechanism whereby it exerts its effects. It has been shown to accelerate the destruction of indoleacetic acid in vitro 3 and, in this behaviour, resembles monohydric phenols which are required in the indoleacetic acid oxidase system4. Maleic hydrazide exists as 6-hydroxy-3(2H)-pyridazinone5 and may be expected to exhibit phenolic properties under physiological conditions.

ALTHOUGH phloroglucinol itself seldom occurs in plants it has been implicated in the biosynthesis of ring A of the flavonoid compounds1,2. In the course of a study of the metabolism of the glucoside, phloridzin, in Malus, leaf disks were fed phloroglucinol together with glucose labelled with carbon-14, and although phloridzin synthesis was unaffected a new compound was detected in chromatograms which has been tentatively identified as phlorin3, the glucoside of phloroglucinol.

METHYL salicylate has been found to occur both in the free state1 and as the aglycone of a primeveroside, gaultherin2 in Gaultheria procumbens L. (Ericaceae).

Dans deux varietes deMetrosideros polymorpha Gaud. (Myrtaceae), nous avons trouve les favanoides suivants: arabinoside-3, galactoside-3, rhamnoside-3-quercetine, et arabinoside-3, thamnoside-3-myricetine; en outre, deux glycosides en moindre quantite.