Isomaltooligosaccharides (IMOs) – Global Prebiotic Association (2024)

Prebiotic Type Spotlight: Isomaltooligosaccharides (IMOs)

Last Updated November 2023

Each edition of GPA’s Prebiotic Spotlight focuses on a specific prebiotic type to raise awareness around the prebiotic itself, its sources, any notable and/or recent research, and how it is used in the marketplace. In this issue, isomaltooligosaccharides (IMOs) are highlighted.

Overview

IMOs are low-degree polysaccharides with at least one α-(1→6) glycosidic bond between glucose residues and a monosaccharide number of 2-5 (Chen et al., 2022). They are found naturally in soy sauce, sake, rice miso, honey, and fermented foods such as kimchi and sourdough bread and commercially from starch-derived sources (Palaniappan and Emmambux, 2023). IMOs are partially digested in the human body by brush border enzymes, including maltase/glucoamylase and isomaltase, while the undigested oligosaccharides get fermented in the large intestines, leading to beneficial gastrointestinal effects and prebiotic properties (Chen et al., 2022).

Benefit Areas

IMOs’ various prebiotic effects on human health have been explored throughout the years, which include:

Modulating the gut microbial profile (Goffin et al., 2011; Yen et al., 2011).
Improving metabolic disorders like hyperlipidemia and cardiovascular disease risk by modulating blood lipid profiles (Sunarti et al., 2022; Wang et al., 2001).
Relieving constipation through improving bowel movements, stool output, and fecal acetate and propionate concentrations in elderly subjects (Chen et al., 2001; Yen et al., 2011).
Demonstrating anticarcinogenic effects in preclinical settings, including cell proliferation inhibition and cell apoptosis induction (Xiao et al., 2011).

Sources

IMOs naturally occur in small quantities in honey, soy sauce, sake, rice miso, and some fermented foods such as kimchi and sourdough bread (Chen et al., 2022; Gourineni et al., 2018; Palaniappan & Emmambux, 2023), making these unviable options economically for the extraction of IMOs (Cardoso et al., 2021). Instead, IMOs are commonly derived commercially from the enzymatic processing of starch via transglycosylation of hydrolyzed starch from two common bases – corn and tapioca, to be used as functional sweeteners. IMOs can also be made by bacterial fermentation of sucrose in the presence of a maltose acceptor by a glucosyltransferase enzyme such as dextransucrase (Gourineni et al., 2018). The production of differently structured IMOs consists of choosing different biocatalysts and proportion of glycosyl-acceptor donors to regulate the degree of polymerization (Palaniappan & Emmambux, 2023). The IMO structure determines their physicochemical and biological properties such as viscosity, solubility, sweetness, as well as influences their prebiotic potential. For example, long-chain IMOs demonstrate higher prebiotic potential for being more resistant to intestinal degrading enzymes than short-chain ones (Cardoso et al., 2021; Palaniappan & Emmambux, 2023). As such, the structure of IMOs is essential for their utilization in different applications, including functional foods and drinks, infant formulas, dental and natural sweetener preparations, animal feed, and medical applications (Cardoso et al., 2021).

Dose Range

IMOs have a recommended daily dose for consumption of 30 g in a healthy adult (Palaniappan & Emmambux, 2023). Nonetheless, they are commonly used in clinical settings at 10 g/day for 4 weeks (Chen et al., 2001; Yen et al., 2011), and have been reported to be well tolerated up to 68.5 g/day without causing side effects (Gourineni et al., 2018). IMOs have been Generally Recognized as Safe (GRAS) by the United States (US) Food and Drug Administration (FDA) since 2016 (FDA, 2016), and accepted as novel food ingredients by numerous jurisdictions around the world including Health Canada (HC) in 2012, European Food Safety Authority (EFSA) in 2010, and Food Standards Australia New Zealand (FSANZ) in 2017 (EFSA, 2010; FSANZ, 2017; HC, 2012).

Recent Research

The evaluation of IMO consumption by humans is an exciting research area with potential for growth. For example, on clinicaltrials.gov one study is currently recruiting for the use of panosyl-IMO as an adjunctive to proton pump inhibitor (PPI) therapy for the treatment of gastroesophageal reflux disease (GERD) (ClinicalTrials.gov, 2023). Meanwhile, on PubMed, using the term “isomaltooligosaccharides” retrieved 19 articles published this year, with most being reviews, in vitro, or animal studies (PubMed, 2023). An in vivo study by Sharma et al. (2023) investigated the protective effects of an IMO-containing synbiotic mix with two probiotics, Bifidobacterium longum Bif10 and Bifidobacterium breve Bif11, and two prebiotics, IMOs and Finger millet arabinoxylan (FM-AX), against dextran sodium sulphate in induced ulcerative colitis (UC) male Balb/c mice for 25 days. While the individual components ameliorated symptoms such as disease activity index, colon histological damage, gut-bacterial dysbiosis and inflammation, the synbiotic mix was more potent in decreasing the tumor necrosis factor α (TNF-α) and lipocalin levels, increasing anti-inflammatory markers such as interleukin-10 and interleukin-22, and improving short chain fatty acid levels in the cecum content (Sharma et al., 2023). Animal studies are an important initial step in understanding the safety and efficacy of IMOs, while clinical trials are needed to substantiate their use in humans.

How are IMOs used in the marketplace?

IMOs have gained commercial interest for their prospective applications in the food, pharmaceutical, and cosmetic industries. In addition to their production from low-cost, widely available agricultural products such as cereal starches, roots, and tubers (potatoes), IMOs are low in calories, suitable humectants, have low viscosity, low water activity, high moisture retaining capacity and solubility, resistance to crystallization, stability within pH 4-6, high stability during food processing, and relative sweetness levels of about 60% of sucrose (Palaniappan & Emmambux, 2023). There is a growing global demand for the application of IMOs in both the food and feed industries, with the highest market share in 2022 reported for food grade and beverage products, led in order by the regions of North America, Europe, Asian-Pacific, South America, and the Middle East and Africa (MarketWatch, 2023a). The global IMO market size was valued at $111.5 million USD in 2022 and is estimated to grow at a compound annual growth rate (CAGR) of 3.4 percent, reaching $141.4 million USD in 2029 (MarketWatch, 2023b).

Isomaltooligosaccharides (IMOs) – Global Prebiotic Association (2024)

Prebiotic Type Spotlight: Isomaltooligosaccharides (IMOs)

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