Category Archives: dysbiosis

Codonopsis: A Novel Herbal Approach to Hydrogen Sulphide Gas-Producing Bacteria

When preparing for my recent lecture at the 11th Herbal & Naturopathic International Conference – Using Herbal Medicines to Modify the Microbiota – I came across an interesting study that looked at the impact of dang shen (Codonopsis pilosula) on the gut microbiota – and specifically gastrointestinal concentrations of Desulfovibrio spp. – a key gastrointestinal hydrogen-sulphide gas-producer.

Most species of bacteria in the colon produce hydrogen gas as a byproduct of fermentation. Some of this microbially-produced hydrogen stays as hydrogen, but some is consumed by other bacteria or archaea. These hydrogen consumers are termed hydrogenotrophs. Hydrogen is shunted down one of three pathways, into methane (by methanogens), acetate (by acetogens), and hydrogen sulphide (via sulphate-reducing bacteria).

This hydrogen pathway is important because excess production of hydrogen sulphide gas has been linked to colonic inflammation, increased gut permeability, visceral hypersensitivity (one of the main drivers of IBS), inflammatory bowel disease (IBD), and colorectal cancer. Sulphate-reducing bacteria (SRB) are also postulated to play a causative role in some cases of small intestinal bacterial overgrowth (SIBO) – commonly referred to as hydrogen-sulphide SIBO.

Agents capable of reducing populations of these bacteria are sorely needed, and to date there has been little research done into agents proficient at decreasing SRB populations. So, I was super excited to come across this study that looked at the impact of dang shen on one of the main hydrogen-sulphide gas producers in the human gastrointestinal tract – the Proteobacteria Desulfovibrio spp..

Dang shen is commonly referred to as “poor man’s ginseng”, as it is used for similar purposes as Korean ginseng, but is far less costly and easy to come by. This study utilised a mouse model of IBD to investigate the impact of Codonopsis on the microbiota (Jing et al., 2018). The polysaccharide components were isolated from dang shen roots and administered to the mice. The dose used was equivalent to the high end of the traditionally recommended dose for this herb – 30g/day. Clear prebiotic-like effects were observed, such as increases in concentrations of beneficial members of the gastrointestinal ecosystem, such as Bifidobacterium spp., Akkermansia spp., and Lactobacillus spp.. Conversely, populations of pathobionts like Alistipes spp., and Desulfovibrio spp. were inhibited.

As pointed out, it was the polysaccharides of Codonopsis that demonstrated this capacity to reduce populations of SRB, whilst concurrently increasing beneficial bacteria populations. Thus, we need to use extraction techniques that are capable of extracting the water-soluble dang shen polysaccharides. Customarily in Traditional Chinese Medicine (TCM), Codonopsis is extracted via decoction. This preparation technique would undoubtedly work well to extract out the polysaccharides. Other suitable options would include just chewing up and consuming the root chunks (luckily they taste quite pleasant), adding the root to soups and stews, or grinding the chunks into a powder and using this in smoothies etc…

I have only just started using Codonopsis for this application in clinic, so I haven’t yet had the opportunity to systematically observe the impact on GIT concentrations of SRB. But I wanted to get this research out there so that others could start trialling this herb – as tools to address an overgrowth of hydrogen sulphide-producing bacteria are few and far between.

I am very curious to get others feedback on the prescription of Codonopsis as an anti-Desulfovibrio agent. Feel free to post your experiences below.

Note: For a limited time, Probiotic Advisor is offering FREE access to Dr Hawrelak’s 1-hour webinar on Using Herbal Medicines to Modify the Microbiota – enrol today!

Jason Hawrelak
Chief Research Officer
Probiotic Advisor

Jing, Y., Li, A., Liu, Z., Yang, P., Wei, J., Chen, X., … Zhang, C. (2018). Absorption of Codonopsis pilosula Saponins by Coexisting Polysaccharides Alleviates Gut Microbial Dysbiosis with Dextran Sulfate Sodium-Induced Colitis in Model Mice. BioMed Research International, 2018, 1–18.

Probiotics Prevent SIBO in Proton Pump Inhibitor Users

Proton pump inhibitor (PPI) medications are one of most frequently utilised classes of medicines. Primarily used to treat gastro-oesophageal reflux disease (GORD), gastritis and peptic ulcer disease, use of these medications has risen sharply over the past two decades. In fact, utilisation has increased by over 1300% over this time! Commonly used PPIs include omeprazole (Losec), lansoprazole (Zoton), esomeprazole (Nexium), pantoprazole (Somac) and rabeprazole (Pariet). Nexium alone accounts for over 19 million prescriptions in the US annually. In Australia, during 2013-14 there were over 19 million prescriptions written for PPIs – quite impressive for a nation of only 24 million people!

The capacity of PPIs to increase risk of Small Intestinal Bacterial Overgrowth (SIBO) had been debated (at least in some circles) until a meta-analysis published in 2013 showed conclusively that PPI use increased the odds of developing SIBO. Pooled data showed over a 7.5-fold increased risk of SIBO development in PPI users.

Given the substantial SIBO-risk associated with their use and the massive frequency of utilisation, it is not surprising that SIBO diagnosis and awareness has increased dramatically over the past decade. This is even more worrying in light of data suggesting that up to 70% of patients taking PPIs are doing so inappropriately!

So, is there anyway to decrease the risk of SIBO development in those patients taking PPIs? It turns out that the right probiotic preparation is indeed capable of reducing the risk of SIBO development.

In a very recent randomised, controlled trial, 128 patients with GORD were allocated to receive either a probiotic supplement or placebo alongside their PPI over a 12-week period. The probiotic group received the strain Lactobacillus reuteri DSM 17938 at a dose of 5 drops per day of an oil preparation (containing a total of 1 x 10^8 CFU/day). SIBO assessment was done (via the Glucose Breath Test) at baseline and again after 12 weeks PPI treatment (esomeprazole). No patients tested positive for SIBO at baseline. Amazingly, SIBO developed in over 56% of patients taking the PPI in the placebo group in just 12 weeks! On the other hand, SIBO only developed in 6% of subjects in the PPI + probiotic group (group difference P<0.001). Additionally, significantly more children in the placebo group developed new gastrointestinal symptoms compared to those in the probiotic group (P=0.026).

This study clearly showed that the co-ingestion of this specific probiotic strain was capable of preventing SIBO from developing in patients taking PPIs. Is this something we could expect from just any probiotic preparation? The research suggests not, with a previous study finding an alternative probiotic preparation comprised of two probiotic strains (Lactobacillus rhamnosus R0011 & L. acidophilus R0052) prescribed at a higher dose (2.0 x 10^9 CFU/day combined) was unable to prevent SIBO development in PPI users. So, at this point, we’d have to conclude that this is an action potentially unique to the L. reuteri DSM 17938 strain.

So, how does this strain work to prevent SIBO from developing? It may have to do with the ability of this strain to produce an anti-microbial compound called reuterin. Reuterin has demonstrated broad action against a range of microorganisms that are commonly found to be overgrown in patients with SIBO – Escherichia, Proteus, Pseudomonas, Staphylococcus, Streptococcus, Enterococcus and Bacteroides spp..

I’ve always argued that probiotics can play pivotal roles in the treatment of SIBO and now we have excellent evidence showing that the right probiotic can prevent its development too.

Jason Hawrelak
Chief Research Officer
Probiotic Advisor

Selected references:
Axelsson LT, Chung TC, Dobrogosz WJ, et al. (1989). Production of a broad spectrum antimicrobial substance by Lactobacillus reuteri. Microbial Ecology in Health and Disease 2(2):131-136.

Belei O, Olariu L, Dobrescu A, et al. (2018). Is it useful to administer probiotics together with proton pump inhibitors in children with gastroesophageal reflux? J Neurogastroenterol Motil 24(1):51-57. PMID: 29291607

Forgacs, I., & Loganayagam, A. (2008). Overprescribing proton pump inhibitors. BMJ, 336(7634), 2-3. doi: 10.1136/bmj.39406.449456.BE
Hollingsworth S, Duncan EL, Martin JH. (2010). Marked increase in proton pump inhibitors use in Australia. Pharmacoepidemoil Drug Saf 19(10):1019-1024.

Lo, W. K. and W. W. Chan (2013). “Proton Pump Inhibitor Use and the Risk of Small Intestinal Bacterial Overgrowth: A Meta-analysis.” Clinical Gastroenterology and Hepatology 11(5): 483-490.