The International Forum is one of the instruments of the International Cooperation for Global Innovation programme being implemented jointly by Phillips Hydrocolloids Research Ltd. (PHRLtd) and San-Ei Gen F.F.I., Inc. to explore the boundaries of scientific areas related to our commercial interests. There is great excitement in exploring inter-disciplinary subjects, and the Arabinogalactan Proteins (AGPs) represent one such area.
They are a large family of glycoprotein found in plants membranes, cell walls and plant secretions, and are ubiquitous throughout the plant kingdom. The Forum was planned to bring together experts in the various aspects of these fascinating materials, which span all the way from controlling plant development to providing important industrial commodities and technical products. Chemical botanists, plant biologists, genetic manipulators, medical doctors, cell biologists and microbiologists have joined chemical and industrial research scientists in the quest to understand these incredibly diverse yet related materials. The two editions of the Journal are the result. The first edition here concentrates on the origin, composition and function within the biological world.
The question is what are the AGPs in composition and in structure and how do they relate to one another ? Although not living themselves, they have a role in providing instructions to cells and through their glycosylphosphosphatidylinositol (GPI) anchor provide communication between plants and their environment. There is an indication too that they might be able to serve as agents to strengthen the human immune system. Professor Bacic opens the curtain on this fascinating class of plant glycoproteins which are becoming increasingly important in plant biology and human health.
Professor Paul Knox takes this fascinating story a stage further. Can these strategic molecules enable us to understand the growth and development of plants at the molecular level? To make progress in this direction it is necessary to understand the genetic codes within the various AGP sequences. Professor Knox cleverly uses monoclonal antibodies to explore the parts and functions of strategic epitopes.
Professor Kieliszewski uses modern synthetic gene technology to design novel glycoproteins, and AGPs, whose properties could resemble the native AGPs. She is able to define many of the structural sequences, particularly the peptide modules which make up the AGPs.
Dr Redgwell shows us that the AGPs are present in several varieties of both Arabica and Robusta coffee, and it is likely that they have diverse functions during the growth and development of coffee. This observation opens up new and exciting physiochemical possibilities for their use as surface active hydrocolloids. As in all investigative studies analytical tools are vital and Professor John Williams, Neil Pickles and Professor Paul Knox demonstrate the power of monoclonal antibodies in the regard.
Thereafter, there is a transition to the microbiological, medical and chemical fields. Coming from plant world AGPs offer a valuable source of dietary fibre. Professor Ushida shows that these remnants and products of plant walls are not metabolised in the stomach but ferment in the colon to give short chain fatty acids which are beneficial to human health. Moreover, Professor Ushida's work demonstrates also that the AGP in the special Acacia gum produced by San-Ei Gen F.F.I., Inc. acts as a prebiotic and stimulates the production of beneficial bacterial in the colon. Professor Aled Phillips and his colleagues in Japan have shown that the effects of dietary supplementation with this material can prove beneficial to humans. With 25 grams per day there is a two-fold increase in serum butyrate which has been shown to play a role against colo-rectal cancer and inflammatory bowel disease. 「View PDF for the rest of the abstract」

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In Europe and Japan both industry and universities have progressively applied more and more resources to develop mechanisms which could unlock the creative resources within universities and lead to wealth creating innovation. Following a review of such university and industry innovation models, it was concluded that every organisation must examine their own situation and devise a plan to meet their own needs. There is no magic formula which can be universally applied.
Accordingly the San-Ei Gen F.F.I.ーPhillips Hydrocolloids Research Ltd Model was designed and implemented. Success parameters were specifically identified for a Global System which would provide creative stimulus, stability, trust, coherence and cross-fertilisation between an academic centre and the company's research and development capability. Progress has been rapid both academically and commercially.
The special features which characterise this innovative relationship are described.
One of the operating instruments of the International Cooperation for Global Innovation programme is this International Forum, the Proceedings of which are published in two editions of this Journal. It enabled the "Global Family" now associated with the cooperation to meet, discuss and explore wider aspects of a subject which has its roots in one of the practical ventures now on-going.

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Arabinogalactan-proteins (AGPs) are highly glycosylated plant macromolecules containing 1-10% (w/w) protein. Their wide use as gums and stabilisers in industry, particularly those from Acacia spp. (eg gum arabic), has stimulated enormous interest and considerable literature on this class of plant gum. More recently they are gaining interest in human health through the practice of complementary medicine such as traditional Chinese herbal medicine where high-molecular-weight glycoconjugates, including AG(P)s, are believed to act as modulators of the immune response. Experimentally, and by analogy with animal proteoglycans and their roles as key recognition molecules, AGPs have been implicated in a variety of biological processes in planta. The cloning of the genes encoding their protein backbones in the mid 1990s and identification and characterisation of a glycosylphosphatidylinositol membrane anchor at the C-terminus of many AGPs, has revealed new insights into their structure and function. This article will provide an overview of our current knowledge of their structure and function.

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Arabinogalactan-proteins (AGPs) are a class of proteoglycans found at the surface of plant cells and in plant gums and secretions. Their functions in these locations are far from clear although various studies involving genetic, inhibitor and immunochemical analyses are indicating roles in cell expansion and the mediation of local cell interactions that underpin developmental events. AGPs are structurally diverse within a plant: Arabidopsis thaliana has at least 40 genes encoding AGP core proteins. Proline-rich domains that carry AGP glycans can be associated with a range of other protein motifs including fasciclin domains. AGP glycan components are decorated arabino-3,6-galactans and are highly heterogeneous. Monoclonal antibodies to AGP glycan epitopes indicate extensive regulation of glycan structure in relation to developmental events in meristems and that the precise developmental occurrence of an AGP epitope can vary between species. The relationship between AGP glycans and core protein diversity has not been fully elucidated and understanding the precise biochemical/cell biological functions of individual AGPs remains a challenge. A chemical disruptor of AGPs, a synthetic phenyl glycoside, known as β-glucosyl Yariv reagent (βGlcY) is a useful tool for the functional analysis of AGPs. The application βGlcY to living cells can result in the disruption of cell proliferation, disruption of cell expansion or modified cell development. In the Arabidopsis seedling root the application of βGlcY blocks the final stage of accelerated cell elongation and also disrupts a staged occurrence of pectin-associated 1,4-galactan. Analysis of the moss Physcomitrella patens indicates the presence of several classes of AGP core protein sequences and the presence of AGP glycan epitopes at all plasma membranes. Physcomitrella grows by tip-extending apical cells and this cell expansion is sensitive to βGlcY application. Genetic and experimental tractability makes this a suitable system for the structural and functional analysis of AGPs as well as providing an evolutionary perspective.

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Hydroxyproline-rich glycoproteins (HRGPs), comprising extensins, proline-rich proteins (PRPs) and arabinogalactan proteins (AGPs) are abundant structural components unique to green algae and green plants where they contribute to cell wall networks and the plasma membrane glycocalyx. HRGPs are extended macromolecules consisting of small repetitive peptide and glycopeptide motifs that form peptide modules and glycomodules of functional significance, as in "mix and match" mode they define the molecular properties of the overall macromolecule. The glycomodules result from a combination of posttranslational modifications unique to plants, namely proline hydroxylation/glycosylation that leads either to short arabinooligosaccharide or larger arabinogalactan polysaccharide added to the hydroxyproline residues. The precise oligosaccharides or polysaccharide addition is driven by a sequence-dependent O-Hyp glycosylation code recently elucidated in this laboratory: contiguous Hyp residues direct the addition of homo-arabinooligosaccharides to Hyp, while clustered non-contiguous Hyp residues direct the addition of a complex arabinogalactan heteropolysaccharide often containing glucuronic acid and rhamnose in addition to arabinose and galactose. This advance in combination with synthetic gene technology now allows us to design novel glycoproteins, arabinogalactan-proteins and gums whose properties can be optimised to provide new fibres, filters, films, pharmaceuticals and foods.

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The arabinogalactan polysaccharides in the cell walls of coffee beans exist in part, or in total, as arabinogalactan-proteins (AGPs). The occurrence of AGPs was confirmed in several varieties of both Arabica and Robusta species of coffee. Microscopic studies of the distribution of AGPs in the cell wall was carried out using the β-glucosyl Yariv reagent and two monoclonal antibodies specific for two epitopes which may exist in AGPs. Although the AGPs were distributed across the width of the wall some forms appeared to be concentrated only in the layer adjacent to the cell lumen, indicating possible differences in the location of variant structural forms of the parent polymer. During roasting the arabinogalactan moiety underwent dramatic changes which included a loss of arabinosyl residues and a 10-20 fold reduction in molecular weight. The carbohydrate-protein linkage, as evidenced by the positive reaction to the Yariv reaction, remained in tact even after a long roast. Chemical analysis demonstrated that coffee AGPs also contained between 8-10% glucuronic acid and therefore had the physical properties of polyelectrolytes. A physicochemical study on the functional properties of coffee AGPs showed that they possessed rheological features which suggested they could be a useful hydrocolloid with properties analogous to surface active polymers such as Acacia gum.

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Immunological methods can be utilised in the characterisation of gums in a number of ways: the identification and quantification of gums from different species; the detection of adulterating gums in foods; and the functional and structural characterisation of the gum molecule. These approaches are applicable to any hydrocolloid, but here we present examples of each of these elements using gum arabic.

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Acacia gum (Gum arabic) has previously been tested for its properties as non-digestible polysaccharide. Its promotive effect on Bifidobacteria and propionic acid production in the large intestine has been so far suggested. However, there has been little information about the chemical and physical characteristics of acacia gum tested in previous studies. For this reason standardized samples were used for the present experiments, based on a specific species of gum arabic (Acacia(sen)SUPER GUM™). In our experiment, using a pig in vitro and in vivo model to investigate the behavior of these accurately characterized samples of gum arabic on the fermentation traits in the large intestine and to determine the responsible bacteria for its fermentation. Propionate production was apparently stimulated by the specific gum arabic independently of molecular weight. Next to propionate, acetate was also produced from this gum arabic. To a lesser extent valeric acid and butyrate were produced with relatively long time lag. Temperature gradient gel electrophoresis (TGGE) analysis on 16S rDNA showed a transition of predominant bacteria during incubation or enrichment. Several 16S rDNA bands detected at the start of enrichment disappeared and replaced by several others. From the sequence of results, a potent polymer degrading propionate producer, Prevotella ruminicola, was suggested to be the most enriched bacterium and the specific bacteria responsible for gum arabic fermentation in the large intestine. Indeed, this bacterium was predominantly isolated from the enrichment culture with Acacia(sen)SUPER GUM™ EM2 medium. Two weeks of feeding 5% or 10% dietary gum increased proportion of pig cecal propionate as a result of shift of bacterial composition. The feeding of Acacia(sen)SUPER GUM™ EM2 also reduced ammonia concentration. Propionate, as a precursor of hepatic gluconeogenesis, may reduce the use of amino acid in gluconeogenesis. This implies the reduction of ammoniogenesis which may help the patients of hepatic and renal disorder. This suggests an additional potential of the gum arabic Acacia(sen)SUPER GUM™ EM2 as a dietary fiber, in addition to its effect on digesta transit and increase in stool mass, glucose and bile acid absorption, based on its physical properties.

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Anecdotal evidence suggests that high fibre supplementation of dietary intake may have health benefits in renal disease related to alterations in circulating levels of short chain fatty acids. The aim of this study was to examine the effect of dietary supplementation with a gum arabic sample of standardised molecular characteristics, Acacia(sen) SUPER GUM™EM2 (SUPERGUM™), on systemic levels of butyrate in normal human subjects, and to examine the potential role of butyrate in modifying the generation of the pro-fibrotic cytokine TGF-β1 by renal epithelial cells in vitro. Following 8 weeks of dietary supplementation with 25g/day of SUPERGUM™ there was a 2 fold increase in serum butyrate (n=7, p=0.03). In vitro work demonstrated that exposure of renal epithelial cells to elevated concentrations of butyrate suppressed both basal and stimulated TGF-β1 synthesis. The action of butyrate was mediated by suppression of the ERK MAP kinase signalling pathway. In addition, butyrate exposures reduced the response of renal epithelial cells to TGF-β1 as assessed by luciferase activity of a TGF-β responsive reporter construct. Attenuation of TGF-β1 signalling was associated with reduced phosphorylation of Smad 2/3 and decreased trafficking of TGF-β1 receptors into signalling, non-lipid raft associated membrane fractions. The potential importance of these findings to renal disease are discussed.

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Acorns are the fruits of beech(Fagus L.), oak(Quercus L.),evergreen chinquapin(Castanopsis Spach.), and tanoak(Pasania Oerst.) trees in the family Fagaceae, which are widespread in the Temperate Zone of the Northern Hemisphere. The acorns are in fact types of nuts and the eatable portion is the cotyledon in the seeds. In the pre-farming period, the nuts constituted one of the most important foodstuffs for the ancients in the Eastern Asia, Central Europe and North America. This review is concerned with the culture and science of acorns.

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