This volume is the first of two volumes dedicated to the Portuguese Carbohydrate Group – GLUPOR – and most of the chapters gather a range of topics presented at the GLUPOR 14 international meeting, which took place in Caparica, Lisbon in January 2023. GLUPOR was created in 1995 by Amélia Pilar Rauter with the mission to promote and internationalize carbohydrate research in Portugal and to support students and young researchers adventuring in the field. Since the inaugural meeting in 1995, GLUPOR meetings have been biennial in a joint initiative with the Portuguese Chemical Society (SPQ). The regular meetings and activities of GLUPOR throughout the years have brought the Portuguese carbohydrate community together and provided unique opportunities to strengthen collaborations nationally and internationally, motivating students and young researchers in the field and advancing research across different areas of Glycosciences.

The first chapter reports original work by Serge Perez and colleagues in a French–Portuguese collaboration combining glycobioinformatics, structural biology and ligand recognition by carbohydrate-binding modules (CBM) to develop the CBMcarb-DB – a novel database dedicated to displaying and analysing the 3D structures of CBM-carbohydrate complexes. CBMcarb-DB aims at more accessible and curated structural data on CBM-carbohydrate binding interactions, enabling knowledge on carbohydrate conformation, mode of binding and functional information on binding specificity. In the era of post-genomics and artificial intelligence, CBMcarb-DB will facilitate structure–function studies and the prediction of a carbohydrate-binding function for newly identified uncharacterized proteins.

The next four chapters cover challenges and the latest advances in carbohydrate chemistry, starting with the chapter by Rita Ventura and colleagues that highlights current methodologies addressing the challenge of regioselectivity and stereoselectivity of glycosidic bond formation, focusing on the synthesis of 1,2-cis-glycosides. In the third chapter, authored by Nadege Lubin-Germain and colleagues, enabling technologies for increasing the efficiency of chemical reactions applied to glycosylation are highlighted considering stereochemical and large-scale control. New green activation conditions (electrochemistry, mechanochemistry, biocatalysis, continuous flux and photocatalysis) are discussed in the context of new opportunities to tackle the increasing complexity of glycosidic targets. The next chapter is dedicated to Sonogashira reactions in carbohydrate chemistry, an area of research developed within a Portuguese–French collaboration between the Carbohydrate Chemistry Group in Lisbon and the Institut de Chimie Organique et Analytique, Université d’Orléans, under the leadership of Amélia Pilar Rauter and Patrick Rollin, respectively. The authors review the chemical aspects and specific challenges related to the use of Sonogashira cross coupling for nucleoside and pseudo-C-nucleoside synthesis. In the fifth chapter, Anne Wadouachi and coworkers dwell on the catalytic transformation of biomass-derived natural resources into valuable compounds for sustainable driven research. The authors provide the state-of-the-art on key parameters that influence the conversion and selectivity of the gold-catalysed oxidation of free sugars and highlight effective alternative activation methods to reduce environmental impact of the sugar oxidation.

The following two chapters dwell on the unique structure and functional properties of polysaccharides for their exploitation in more sustainable applications and highlight the need for research on polysaccharides. In the sixth chapter, Claudia Nunes and co-workers present the latest findings for the use of polysaccharide-based films for food packaging applications. The authors highlight the effect of the incorporation of carbon-based nanomaterials on polysaccharide-based film properties. The next chapter by Elizabete Coelho and co-workers gives an overview of the brewer’s yeast cell wall polysaccharides and their recognition by the innate immune system. The authors review recent results on the structural analysis of yeast polysaccharides and highlight structural changes arising from the brewing process. The authors focus on β-glucans for their immunomodulatory properties, highlighting structural features for interaction with the innate immune system. They also discuss opportunities for brewer’s yeast cell wall polysaccharide applications based on their ability to interact with the innate immune system.

The final chapter authored by Benedita Pinheiro and co-workers is dedicated to the most recent findings in understanding the recognition of complex carbohydrates by the human gut microbiome and its impact on the host’s health. The authors highlight recent archetypal examples of bacterial carbohydrate-binding proteins and integrate the molecular complexity of these systems with the impact for the host. They critically discuss the potential of the fine-tunability of these microbiome carbohydrate-binding proteins for application as molecular tools for diagnosis and therapeutics.

This volume highlights the role of carbohydrates across different fields of science and the importance of Glycoscience research for innovation in Chemistry, Biology and Biotechnology. We sincerely hope that its content will stimulate researchers, particularly young researchers, for the investigation of carbohydrates, which hold many secrets yet to be discovered in fundamental and applied research.

We end this preface by thanking all the authors for their unique contributions and resilience in their continued carbohydrate-inspired research to create knowledge towards a sustainable and healthier world.

Amélia Pilar Rauter

Yves Queneau

Angelina Sá Palma