The content of Sennosides, the main active component of Senna Leaf Extract, is usually 2.5%-5% (HPLC detection). Through interaction with intestinal microorganisms, Rhein anthrone is generated, which stimulates the colon nerve plexus. Increases the frequency of intestinal peristalsis by 40-60% (European Journal of Pharmacology). A double-blind trial showed that 100mg of the standardized extract (including 20mg Sennosides) reduced colon transit time from 72 hours to 24 hours in patients with chronic constipation (a 66.7% reduction) and increased bowel frequency from 1.2 to 3.8 times per week (a 217% increase).
Its mechanism of action includes:
Promote intestinal fluid secretion: Increase intestinal fluid secretion by 300-500ml/ day by activating chloride ion channel (CFTR) (only 100-200ml in control group);
Regulation of intestinal flora: Clinical data showed that 50mg of Senna Leaf Extract daily could increase bifidobacteria abundance by 28% (qPCR detection) and reduce pathogenic bacteria such as Escherichia coli by 42% (16S rRNA sequencing);
Anti-inflammatory effect: Inhibition of the NF-κB pathway (IC50=12μM) reduced IL-6 levels in colitis models by 65% (ELISA).
Safety data showed that short-term use (<7 days) had an adverse reaction rate of only 4.2% (1.8% in the placebo group), mainly mild abdominal pain (2.7%). The EU EMA recommends a maximum daily dose of 30mg Sennosides (equivalent to 600mg of dry leaf extract), with long-term use at least 2 weeks interval to prevent electrolyte imbalance (potassium loss rate ≤0.5mmol/L). A pharmaceutical company’s GRAS certified product (FDA 21CFR 582.20) reduced the risk of intestinal spasms by 73% by delaying the stimulation threshold from 4 hours to 8-12 hours through microencapsulation (clinical trial NCT03452111).
In commercial applications, the production cost of standardized extracts (containing 60% Sennosides) is 120/kg, with a premium of 300,400 /kg for the end product. The global market size will reach $2.1B in 2023 (F&S report), of which functional foods will account for 58% (e.g. the re-purchase rate of digestive tea containing Senna is 72%). A clinical trial (n=500) showed that a combination of probiotics (10⁹ CFU/g) improved the relief rate of chronic constipation from 68% to 89% with Senna alone (p<0.01).
Environmentally and ethically, the share of sustainably grown organic Senna (USDA certified) production has increased from 12% in 2015 to 34% in 2023, with a 41% reduction in carbon intensity (LCA analysis). Its window of action (6-12 hours) and dose-dependence (EC50=15mg Sennosides) make it a first-line natural regimen for short-term laxation, but without the risk of interaction with diuretics/digoxin (PK parameter AUC↑22%).