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Quantitative analysis of glucose, fructose, sucrose, and maltose in different geographic origin honey samples in the world using the Fourier transform infrared (FTIR) spectroscopy and chemometrics such as partial least squares (PLS) and principal component regression was studied. The calibration series consisted of 45 standard mixtures, which were made up of glucose, fructose, sucrose, and maltose. There were distinct peak variations of all sugar mixtures in the spectral "fingerprint" region between 1500 and 800 cm(-1). The calibration model was successfully validated using 7 synthetic blend sets of sugars. The PLS 2nd-derivative model showed the highest degree of prediction accuracy with a highest R(2) value of 0.999. Along with the canonical variate analysis, the calibration model further validated by high-performance liquid chromatography measurements for commercial honey samples demonstrates that FTIR can qualitatively and quantitatively determine the presence of glucose, fructose, sucrose, and maltose in multiple regional honey samples.

The phytoalexin resveratrol (trans-3,5,4'-trihydroxy-stilbene), a natural component of resistance to fungal diseases in many plants, is synthesized by the enzyme trihydroxystilbene synthase (stilbene synthase, EC 2.3.1.95), which appears to be deficient or lacking in susceptible plants. Earlier workers isolated a stilbene synthase gene (Vst1) from grapevine (Vitis vinifera L.), which has subsequently been introduced as a transgene into a range of species to increase resistance of hosts to pathogens to which they were originally susceptible. Papaya (Carica papaya L.) is susceptible to a variety of fungal diseases, including root, stem, and fruit rot caused by the pathogen Phytophthora palmivora. Since resveratrol at 1.0 mM inhibited mycelium growth of P. palmivora in vitro, we hypothesized that papaya resistance to this pathogen might be increased by transformation with the grapevine stilbene synthase construct pVst1, containing the Vst1 gene and its pathogen-inducible promoter. Multiple transformed lines were produced, clonally propagated, and evaluated with a leaf disk bioassay and whole plant response to inoculation with P. palmivora. RNA transcripts of stilbene synthase and resveratrol glycoside were induced in plant lines transformed with the grapevine pVst1 construct shortly after pathogen inoculation, and the transformed papaya lines exhibited increased resistance to P. palmivora. The immature transformed plants appear normal and will be advanced to field trials to evaluate their utility.

Chlorogenic acids are major secondary metabolites found in coffee seeds. The accumulation of chlorogenic acids and free quinic acids was studied in Coffea arabica cv. Tall Mokka and Coffea canephora seeds. Growth stages are specified from I to V, corresponding to rapid expansion and pericarp growth (I), endosperm formation (II), mature (green) (III), ripening (pink) (IV), and fully ripened (red) (V) stages. We detected monocaffeoylquinic acids (3CQA, 4CQA and 5CQA), dicaffeoylquinic acids (3,4diCQA, 3,5diCQA and 4,5diCQA) and a monoferuloylquinic acid (5FQA) in whole fruits (stage I), pericarps and seeds. The most abundant chlorogenic acid was 5CQA, which comprised 50-60% of the total of C. arabica and 45-50% of C. canephora seeds. The content of dicaffeoylquinic acid, mainly 3,5d diCQA, was high in C. canephora. A high content of 5FQA was found in seeds of stages III to V, especially in C. canephora. Total chlorogenic acids were accumulated up to 14 mg per fruit in C. arabica and 17 mg in C. canephora, respectively. In contrast, free quinic acid varied from 0.4-2.0 mg (C. arabica) and 0.2-4.0 mg (C. canephora) per fruit during growth. High biosynthetic activity of 5CQA, which was estimated via the incorporation of [U-14C]phenylalanine into chlorogenic acids, was found in young fruits (perisperm and pericarp) in stage I, and in developing seeds (endosperm) in stages II and III. The biosynthetic activity of chlorogenic acids was clearly reduced in ripening and ripe seeds, especially in C. canephora. Transcripts of PAL1, C3′H and CCoAMT, three genes related to the chlorogenic acid biosynthesis, were detected in every stage of growth, although the amounts were significantly less in stage V. Of these genes, CCoAMT, a gene for FQA biosynthesis, was expressed more weakly in stage I. The transcript level of CCoAMT was higher in seeds than in pericarp, but the reverse was found in PAL1. The pattern of expression of genes for the CQA and FQA synthesis is roughly related to the estimated biosynthetic activity, and to the accumulation pattern of chlorogenic acids.

Changes occurring in phenolic compounds and purine alkaloids, during the growth of seeds of cacao (Theobroma cacao) cv. Trinitario, were investigated using HPLC-MS/MS. Extracts of seeds with a fresh weight of 125, 700, 1550, and 2050 mg (stages 1-4, respectively) were analyzed. The phenolic compounds present in highest concentrations in developing and mature seeds (stages 3 and 4) were flavonols and flavan-3-ols. Flavan-3-ols existed as monomers of epicatechin and catechin and as procyanidins. Type B procyanidins were major components and varied from dimers to pentadecamer. Two anthocyanins, cyanidin-3-O-arabinoside and cyanidin-3-O-galactoside, along with the N-phenylpropernoyl-l-amino acids, N-caffeoyl-l-aspartate, N-coumaroyl-l-aspartate, N-coumaroyl-3-hydroxytyrosine (clovamide), and N-coumaroyltyrosine (deoxyclovamide), and the purine alkaloids theobromine and caffeine, were present in stage 3 and 4 seeds. Other purine alkaloids, such as theophylline and additional methylxanthines, did not occur in detectable quantities. Flavan-3-ols were the only components to accumulate in detectable quantities in young seeds at developmental stages 1 and 2.