Bioengineered Wheat Arabinoxylan - Fostering Next-Generation Prebiotics Targeting Health-Related Gut Microbes

Area of Science:

• Microbiology
• Nutrition Science
• Biochemistry

Background:

• Dietary fibers, particularly prebiotic fibers, are crucial for gut microbiota modulation.
• Structural heterogeneity of fibers like wheat arabinoxylan (AX) influences microbial utilization and health benefits.
• Understanding AX structure-activity relationships is key for developing targeted prebiotics.

Purpose of the Study:

• To investigate how molar mass and chemical structure of wheat AX impact the growth and metabolism of *Faecalibacterium prausnitzii* and *Lacticaseibacillus rhamnosus*.
• To evaluate the prebiotic potential of modified AX structures.
• To identify optimal AX modifications for enhancing beneficial gut bacteria.

Main Methods:

• Wheat AX was fractionated into low, medium, and high molar masses (LAX, MAX, HAX).
• AX samples were enzymatically modified to alter xylose unit substitution patterns.
• Microbial growth and short-chain fatty acid (SCFA) production by *F. prausnitzii* and *L. rhamnosus* were measured using modified AX substrates.

Main Results:

• Modified AX samples generally exhibited superior prebiotic scores compared to unmodified AX.
• Low molar mass AX (LAX), particularly with doubly substituted xylose units, demonstrated the highest prebiotic potential and SCFA production.
• Singly or doubly substituted AX consistently promoted *L. rhamnosus* growth, while AX with all arabinose removed preferentially impacted *F. prausnitzii*.

Conclusions:

• Bioengineered wheat AX, especially LAX with specific substitution patterns, holds significant potential as next-generation prebiotics.
• Tailoring AX structure can selectively enhance the growth and metabolic activity of key health-associated gut microbes.
• These findings provide a basis for designing targeted prebiotic interventions for gut health.