We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Identification of plastic-degrading bacteria in the human gut
Summary
Scientists discovered bacteria in the human gut that can break down common plastics like polyethylene and polypropylene, though all the plastic-degrading species identified were opportunistic pathogens. The bacteria could physically and chemically alter plastic surfaces but only achieved limited depolymerization. This finding raises the question of whether microplastic exposure in the gut could promote the growth of potentially harmful bacteria while they attempt to digest the plastic.
Environmental pollution caused by the excessive use of plastics has resulted in the inflow of microplastics into the human body. However, the effects of microplastics on the human gut microbiota still need to be better understood. To determine whether plastic-degrading bacteria exist in the human gut, we collected the feces of six human individuals, did enrichment cultures and screened for bacterial species with a low-density polyethylene (LDPE) or polypropylene (PP)-degrading activity using a micro-spray method. We successfully isolated four bacterial species with an LDPE-degrading activity and three with a PP-degrading activity. Notably, all bacterial species identified with an LDPE or PP-degrading activity were opportunistic pathogens. We analyzed the microbial degradation of the LDPE or PP surface using scanning electron microscopy and confirmed that each bacterial species caused the physical changes. Chemical structural changes were further investigated using X-ray photoelectron spectroscopy and Fourier-transform-infrared spectroscopy, confirming the oxidation of the LDPE or PP surface with the formation of carbonyl groups (C=O), ester groups (CO), and hydroxyl groups (-OH) by each bacterial species. Finally, high temperature gel permeation chromatography (HT-GPC) analysis showed that these bacterial species performed to a limited extent depolymerization. These results indicate that, as a single species, these opportunistic pathogens in the human gut have a complete set of enzymes and other components required to initiate the oxidation of the carbon chains of LDPE or PP and to degrade them. Furthermore, these findings suggest that these bacterial species can potentially biodegrade and metabolize microplastics in the human gut.
Sign in to start a discussion.
More Papers Like This
Polyethylene Terephthalate Hydrolases in Human Gut Microbiota and Their Implications for Human Health
Researchers searched the genomes of healthy human gut bacteria and discovered enzymes capable of breaking down PET, one of the most common plastics found in food and drink packaging. They identified multiple bacterial species in the human gut that produce these PET-degrading enzymes. This discovery suggests that gut microbes may play a role in processing the microplastics people swallow, though it also raises questions about whether the breakdown products could affect human health.
Marine bacteria capable of enzymatic degrading of low- and high-density polyethylene: Toward sustainable mitigation of marine microplastic pollution
Scientists discovered ocean bacteria that can break down common plastic types found in marine pollution, with some bacteria destroying up to 17% of the plastic in lab tests. These naturally occurring bacteria could potentially be used to help clean up the tiny plastic particles that contaminate our oceans and eventually enter our food chain through seafood. While still in early research stages, this finding offers hope for a biological solution to reduce the microplastics that may pose health risks when we consume contaminated fish and shellfish.
PET Microplastics Affect Human Gut Microbiota Communities During Simulated Gastrointestinal Digestion. First Evidence of Plausible Polymer Biodegradation During Human Digestion
Researchers simulated gastrointestinal digestion and found that PET microplastics altered human gut microbiota community composition, and provided first evidence of plausible partial polymer biodegradation during passage through the human digestive tract.
Gut microbiota, a key to understanding the knowledge gaps on micro-nanoplastics-related biological effects and biodegradation
This review explores how micro- and nanoplastics affect the community of microorganisms living in the gut, and how those same gut microbes might be able to break down plastic particles. Swallowed microplastics can disrupt the balance of gut bacteria, potentially leading to various diseases. On the other hand, some gut bacteria can actually degrade plastics into smaller, less harmful molecules, opening a possible avenue for biological cleanup.
Characterization of plastic degrading bacteria isolated from sewage wastewater
Researchers isolated bacteria from sewage wastewater that can degrade plastic, with two Pseudomonas strains achieving 25% weight loss of plastic pieces over 120 days. Chemical analysis confirmed the bacteria were breaking down and transforming the plastic polymer bonds. These plastic-eating bacteria could offer a green biotechnology approach to reducing microplastic pollution in wastewater systems.