Fructooligosaccharide Production and Enzymatic Applications

Fructooligosaccharides (FOS) are short-chain fructans composed of β-(2→1) linked fructose units attached to a terminal glucose. They have gained prominence as low-calorie sweeteners and prebiotics that selectively stimulate beneficial gut microbiota. Industrial production of FOS usually relies on enzymatic transformation of sucrose or inulin using fructosyltransferases and β-fructofuranosidases, often sourced from fungi or bacteria. Key challenges include maximising transfructosylation over hydrolysis, achieving high product yields under mild conditions, and simplifying downstream purification. Advances in enzyme discovery, protein engineering and reactor design have expanded the repertoire of biocatalysts capable of high tolerance to substrate concentrations, broad pH and temperature optima, and resistance to proteolysis. Coupled processes such as in situ conversion in food matrices, integrated membrane reactors for continuous by-product removal, and microbial biopurification strategies enhance both efficiency and sustainability. The resulting FOS preparations find application as functional ingredients in beverages, dairy and plant-based foods, and hold potential in pharmaceutical formulations to modulate host metabolism and immunity.

Research from Nature Portfolio

Recent studies have described a novel alkaline, low-temperature-active invertase from a Bacillus species that combines high sucrose tolerance with robust transfructosylation activity under mild conditions. The recombinant enzyme displays optimum activity at pH 8.0 and retains substantial activity down to 0 °C, while tolerating sucrose concentrations in excess of 2 M. Structural analysis revealed an unusually flexible catalytic loop enriched in glycine residues and a positively charged catalytic pocket, features that underpin both its alkaline adaptation and resistance to substrate inhibition. This biocatalyst exemplifies a class of glycoside hydrolases with tailored properties for efficient FOS synthesis at scale without elevated energy input.

Fructooligosaccharide Production and Enzymatic Applications publication trend

The graph below shows the total number of articles in fructooligosaccharide production and enzymatic applications across all publications each year (not limited to Nature Index journals).

Technical terms

Fructooligosaccharides (FOS): Short-chain fructans with 2–5 fructose units and a terminal glucose, used as prebiotic sweeteners.

β-Fructofuranosidase: An enzyme that hydrolyses and transfructosylates sucrose to generate FOS.

Fructosyltransferase: A class of enzymes catalysing the transfer of fructosyl units from sucrose to acceptor sugars, promoting FOS synthesis.

Transfructosylation: Enzymatic reaction in which a fructosyl moiety is transferred from one sugar molecule to another, forming longer fructan chains.

Prebiotic: A dietary substance selectively utilised by beneficial gut microbes, conferring health benefits to the host.

References

1. Characterization of a novel low-temperature-active, alkaline and sucrose-tolerant invertase. Scientific Reports (2016).
2. Development of a functional prebiotic strawberry preparation by in situ enzymatic conversion of sucrose into fructo-oligosaccharides. Food Research International (2023).
3. Efficient Degradation for Raffinose and Stachyose of a β-D-Fructofuranosidase and Its New Function to Improve Gel Properties of Coagulated Fermented-Soymilk. Gels (2023).
4. Purification and characterization of crude fructooligosaccharides extracted from red onion (Allium cepa var. viviparum) by yeast treatment. Microbial Cell Factories (2024).
5. Development and Characterization of an Enzyme Membrane Reactor for Fructo-Oligosaccharide Production. Membranes (2019).