Microplastic
adsorption.
A strain-specific study.

Global annual plastic production has surpassed 400 million metric tons, with polyethylene (PE) and polypropylene (PP) collectively accounting for a substantial proportion of total output. PE, PP, polyamide (PA), and polyethylene terephthalate (PET) are among the most prevalent microplastics identified in environmental matrices.

Evidence of human exposure to microplastics has accumulated in recent years. Published studies cited in the source report describe detection of plastic particles in human blood and lung tissue, including PET, PE, PP, and other polymer types. Additional experimental literature has reported inflammatory responses associated with selected microplastics in cellular and animal models.

In this context, the SEQUIVA study employed fluorescent microparticles to evaluate whether selected probiotic strains associated with the SEQUIVA probiotic product possess the capacity to adsorb PP, PE, and PET particles under controlled in-vitro conditions.

Materials & methods

A 30 microliter aliquot of bacterial culture at an optical density of 600 nm (OD600) = 1.2 was transferred into a 2 mL centrifuge tube containing 270 microliters of PE, PET, or PP fluorescent microparticle working solution (0.16 mg/mL; particle size, 0.1 micrometer). The tubes were incubated in the dark on a shaking incubator at 37 degrees C and 130 rpm for 4 hours.

Following incubation, the mixtures were centrifuged at 2000 rpm for 10 minutes. A 200 microliter aliquot of the supernatant was transferred into a 96-well black microplate, and fluorescence intensity was measured using a Thermo Fisher Scientific multimode microplate reader at an excitation wavelength of 485 nm and emission wavelength of 525 nm.

These findings provide preliminary in-vitro evidence that selected strains associated with the SEQUIVA probiotic product can adsorb common microplastic particles under the tested assay conditions. The data are most appropriately described as strain- and polymer-specific adsorption results.

The scientifically supported terminology is adsorption, not absorption. The assay measures the reduction in fluorescent particles remaining in the supernatant after incubation and centrifugation; it does not establish plastic degradation or human microplastic removal.