Berberine features poor water solubility and low oral bioavailability, attributed to low membrane permeability, P‑glycoprotein (P‑gp)‑mediated efflux, enterohepatic recirculation and intracellular accumulation. Even at low blood concentrations, BBR still exerts potent biological functions, which implies that active metabolites are formed after entering the body.

Berberine is metabolized rapidly in vivo, primarily by the liver, intestinal tract and gut microbiota. The liver serves as its principal metabolic organ. Phase I metabolism includes demethylation, demethylenation, reduction and hydroxylation; subsequent Phase II transformations such as glucuronidation, sulfation and methylation also constitute major metabolic pathways.

Recent research reveals that berberine and its derivatives boast a wide spectrum of pharmacological activities, including hypoglycemic, hypolipidemic, antioxidant, gut microbiota‑modulating, anti‑Alzheimer’s and anti‑tumor effects.

🦠 Antimicrobial Activity

Berberine demonstrates outstanding broad‑spectrum antimicrobial properties.

• Against bacteria: berberine and its derivatives suppress bacterial proliferation by inhibiting β‑lactamase activity and disrupting core physiological processes such as cell wall synthesis and protein metabolism. Combined with conventional antibiotics, it generates prominent synergistic inhibition against drug‑resistant bacteria common in livestock farming.
• Against fungi: berberine compromises fungal membrane integrity, disturbs intracellular enzyme activity and blocks biofilm formation, yielding robust antifungal effects.

Structural studies further confirm that berberine derivatives modified at C8, C9, C13 and other positions deliver enhanced antibacterial potency.

🛡️ Gastrointestinal Regulation

Gastrointestinal disorders are frequently accompanied by mucosal barrier injury, dysbiosis and immune dysregulation, creating an urgent demand for effective interventions.

Modern studies show berberine stabilizes and reinforces intestinal barrier function through multiple pathways: balancing gut microbiota homeostasis, inhibiting the TLR4 signaling pathway and NLRP3 inflammasome activation, activating the PI3K/Akt/mTOR cascade, boosting goblet cell count and mucosal thickness, upregulating tight junction proteins (occludin, claudin‑1, E‑cadherin), and stimulating vitamin D receptor activity.

It also facilitates intestinal mucosal repair: it elevates the proportion of regulatory T cells (Treg) and the expression of CTLA‑4 on their surface to curb macrophage activation, and promotes barrier restoration by downregulating HSP90AA1 and MAPK14 expression. In short, berberine safeguards intestinal health by strengthening gut barrier integrity and accelerating mucosal injury repair.

✨ Antioxidant Properties

Oxidative stress arises from an imbalance between reactive oxygen species (ROS) generation and endogenous antioxidant defense. This imbalance triggers cellular and molecular damage, disturbs DNA, protein and lipid metabolism, and fuels mutation accumulation and malignant transformation.

Berberine exerts antioxidant effects by cutting ROS production, scavenging excess ROS and boosting cellular antioxidant capacity, with detailed mechanisms outlined below:

• It enhances antioxidant enzyme activity and upregulates glutathione peroxidase expression, clearing surplus reactive oxygen species, lowering malondialdehyde levels and mitigating oxidative stress injury.
• It confers cytoprotection via targeted modulation of oxidative stress signaling pathways. It activates the Nrf2/ARE signaling axis to strengthen cellular antioxidant defense.
• Berberine also inhibits NADPH oxidase activity, curbing ROS formation. It reduces levels of lipid peroxidation and protein oxidation products, thereby lessening oxidative damage to cell membranes and proteins.