Lactic acid bacteria – Potential for control of mould growth and mycotoxins: A review

Disease outbreaks due to the consumption of contaminated food and feedstuff are a recurring problem worldwide. The major factor contributing to contamination are microorganisms, especially fungi, which produce low-molecular-weight compounds as secondary metabolites, with confirmed toxic properties referred to as mycotoxins. Several mycotoxins reported to date are cosmopolitan in distribution and incur severe health-associated risks (including cancer and neurological disorders). Hence, creating awareness among consumers, as well as developing new methods for detection and inactivation is of great importance for food safety. In this review, the focus is on the occurrence of various types of mycotoxins in food and feed associated with risks to humans and livestock, as well as legislation put forth by various authorities, and on presently practiced detoxification methods. Brief descriptions on recent developments in mycotoxin detection methodology are also inlcuded. This review is meant to be informative not only for health-conscious consumers but also for experts in the field to pave the way for future research to fill the existing gaps in our knowledge with regard to mycotoxins and food safety.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1541-4337.2009.00094.x

Mycotoxins in Food and Feed: Present Status and Future Concerns

In the United States, 1 in 8 women will be diagnosed with breast cancer in her lifetime. Along with genetics, the environment also contributes to disease development but what these exact environmental factors are remain unknown. We have previously shown that breast tissue is not sterile but contains a diverse population of bacteria. We thus believe that the host9s local microbiome could be modulating the risk of breast cancer development. Using 16S rRNA amplicon sequencing we show that bacterial profiles differ between normal adjacent tissue from women with breast cancer and tissue from healthy controls. Women with breast cancer had higher relative abundances of Bacillus , Enterobacteriaceae and Staphylococcus . Escherichia coli (member of the Enterobacteriaceae family) and Staphylococcus epidermidis, isolated from breast cancer patients, were shown to induce DNA double stranded breaks in HeLa cells using the γH2AX assay. We also found that microbial profiles are similar between normal adjacent tissue and tissue sampled directly from the tumour. This novel study raises important questions as to what role the breast microbiome plays in disease development or progression and how we can manipulate this microbiome for possible therapeutics or prevention. Statement of significance: This study shows that different bacterial profiles in breast tissue exist between healthy women and those with breast cancer. Higher relative abundances of bacteria, that had the ability to cause DNA damage in vitro , were detected in breast cancer patients, as well as a decrease in some lactic acid bacteria, known for their beneficial health effects, including anti-carcinogenic properties. This study raises the important question as to the role of the mammary microbiome in modulating the risk of breast cancer development.

The Microbiota of Breast Tissue and Its Association with Breast Cancer.

Detoxification of patulin and ochratoxin A, two abundant mycotoxins, by lactic acid bacteria

The food and water we consume are often contaminated with a range of chemicals and heavy metals, such as lead, cadmium, arsenic, chromium, and mercury, that are associated with numerous diseases. Although heavy-metal exposure and contamination are not a recent phenomenon, the concentration of metals and the exposure to populations remain major issues despite efforts at remediation. The ability to prevent and manage this problem is still a subject of much debate, with many technologies ineffective and others too expensive for practical large-scale use, especially for developing nations where major pollution occurs. This has led researchers to seek alternative solutions for decontaminating environmental sites and humans themselves. A number of environmental microorganisms have long been known for their ability to bind metals, but less well appreciated are human gastrointestinal bacteria. Species such as Lactobacillus, present in the human mouth, gut, and vagina and in fermented foods, have the ability to bind and detoxify some of these substances. This review examines the current understanding of detoxication mechanisms of lactobacilli and how, in the future, humans and animals might benefit from these organisms in remediating environmental contamination of food.

Bioremediation and Tolerance of Humans to Heavy Metals through Microbial Processes: a Potential Role for Probiotics?

Impact of lactic acid bacteria on oxidative DNA damage in human derived colon cells

Aim of the present study was a comprehensive investigation of the detoxification capacities of lactic acid bacteria (LAB) towards heterocyclic aromatic amines (HCA) formed during cooking of meat. It has been postulated that LAB prevent genotoxic and/or carcinogenic effects of HCA in laboratory rodents and humans via direct binding mechanisms. We measured the removal of the most abundant cooked food mutagens (AalphaC, PhIP, IQ, MeIQx, DiMeIQx) by eight LAB species. From each species, twelve strains were tested in liquid binding experiments with HPLC coupled with coulometric electrode array detection. The highest removal rates were observed with the representatives of the L. helveticus and S. thermophilus groups, which were seven to eight times more effective than L. kefir and L. plantarum. Strong and statistically significant differences were seen in the binding behaviour of the individual amines, the ranking order of detoxification being AalphaC > DiMeIQx > MeIQx > IQ > PhIP. Results of Salmonella/microsome assays with strain TA98 showed that the binding of AalphaC and PhIP to LAB correlates with the reduction of their mutagenic activities. This study may contribute to the development of strategies concerning the adverse health effects of HCA utilizing highly protective LAB for the production of fermented foods.

Reinhard Stidl

Papers

Detoxification of patulin and ochratoxin A, two abundant mycotoxins, by lactic acid bacteria

Impact of lactic acid bacteria on oxidative DNA damage in human derived colon cells

Binding of heterocyclic aromatic amines by lactic acid bacteria: results of a comprehensive screening trial.

Investigations concerning the long term effects of dietary factors on human health: current topics, methods and new concepts.

Lactobacilli and Fermented Foods