Seed Health’s double-capsule delivers live probiotics in human GI tract simulation study

14 Sep 2021 --- Research supported by Seed Health has investigated a new approach to innovating probiotic and synbiotic compositions via gene sequencing and vitamin B12 synthesis.

The study, published in the International Journal of Molecular Sciences, has revealed Seed Health’s novel dual encapsulation system can safeguard the viability of select probiotic strains in a laboratory simulation of the gastrointestinal tract called Simulator of Human Intestinal Microbial Ecosystem (SHIME).

The company’s Daily Synbiotic consists of a 24-strain synbiotic blend called SH-DS01. In this blend, the Limosilactobacillus reuteri SD-LRE2-IT strain was able to produce vitamin B12 (at 40.57 ug/L), a micronutrient essential both for human cognitive health and a healthier gut microbial community.

Reaching the GI tract
Moreover, the same strain delivered high numbers of metabolically active cells to the gastrointestinal tract, including the small intestine, where immune responses and absorption of metabolites into the bloodstream occur. 

“Using metabolomic profiles, for example vitamin B12 synthesis, coupled with delivery systems that allow for the regiospecific release of live strains in the human gut or a simulated equivalent, offers a new approach to innovating probiotic and synbiotic compositions, especially with novel metabolomes and benefits,” lead study author Dr. Peter Bron tells NutritionInsight.

The metabolome is the totality of small molecules and metabolic intermediates found within a biological sample – meaning what each strain makes inside the cell and releases to the outside.

What’s inside?
The study argues it is “unrealistic” to expect a single probiotic strain to act through multiple mechanisms and impact the variable genetic backgrounds, microbiome composition and dietary habits of consumers. 

Confirmation of vitamin B12 production by L. reuteri SD-LRE2-IT after it was grown in B12-free chemically defined medium (AU = arbitrary units).Therefore, the SH-DS01 blend contains lactobacilli and bifidobacteria, consisting of a dry outer compartment containing polyphenolic compounds derived from pomegranate. 

Seed Health’s cap-in-cap system ViaCap was shown to facilitate the continuous delivery of live organisms within the SHIME system. 

The benefits of SHIME screening
The toolbox for screening and identifying novel probiotic strains has been vastly expanded by leading-edge gene sequencing, what Bron calls “genomic power tools.” 

“Coupling this with metabolite profiling to confirm the functioning of a gene’ signature, and then demonstrating strain viability in a specific delivery system through a simulated human gut model like SHIME, offers a systematic and rapid approach prior to entering clinical trials,” notes Bron.

He adds the SHIME system is the “best simulator” of what goes on in the human gut. “We designed a SHIME experiment because our ViaCap intentionally excludes any synthetic enteric coating agents to protect against acid degradation of the outer capsules,” he explains. 

SHIME models have previously been used by Nexira researching its baobab acacia prebiotic, as well as Glycom for its HMO investigations.

Furthermore, Bron and his research team also wanted to evaluate the regional – meaning across the small intestine equivalent – release profile of Seed Health’s probiotic strains. 

“The B12 de novo synthesis experiment was simply the next evidentiary step to confirm the ‘activity’ of the gene sequences associated with vitamin B12 synthesis.”

Representative flow cytometry dot plots of viable and non-viable probiotic cells in the SH-DS01 capsule (A) at the end of the gastric digestion stage (B), after 1.5 h of small intestinal digestion (C) and at the end of small intestinal digestion (3 h) (D).Next steps to probiotic innovation
Commenting on future research plans, Bron maintains “simulated and in vitro experiments offer insights into what may be happening in vivo.” 

“It is of interest to link the two experiments in this paper to demonstrate the delivery of bioactive vitamin B12 to human systemic metabolism, especially among vegans and vegetarians,” he states. 

“Such evidence would complement our ongoing clinical trials with SHDS-01 and add to the evidence base we have assembled.”

Gut-brain axis in the spotlight
Ultimately, the study highlights the importance of appropriate encapsulation to retain a high viable count and metabolic activity in a simulated small intestinal environment. 

Therefore, this could enable these cells to produce key metabolites such as B vitamins and thereby impact cognitive health through the gut-brain axis.

In past interviews, NutritionInsight extensively covered how mounting research indicates the gut-brain axis physically links intestinal and cognitive health. 

The gut-brain axis further holds major potential for mood NPD and to support mental well-being.

Brain and mood health claims in novel supplement launches continue to climb up, as Innova Market Insight data reveals a 21 percent average annual growth in the category between 2015 and 2019.

Of the leading subcategories, Vitamins/Minerals jumped from 26 percent in 2015 to 34 percent in 2019. 

By Anni Schleicher