Harvest and storage of moist cereal straw - experiments 2013-2014 and 2015-2016

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Tutkimus osoitti: suomenkarjan maitoa kannattaa jatkojalostaa

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Characterisation of erwinias causing blackleg and soft rot in Finland

Potato stems showing blackleg or wilting were collected during 2003-2004 and the erwinias were isolated based on cavity forming on pectate-containing media followed by anaerobic growth test. Bacteri were also isolated from rotting tubers and from water samples collected from rivers in southern and western Finland

Creating novel approaches to mitigate aflatoxin risk in food and feed with lactic acid bacteria - mold growth inhibition and aflatoxin binding

Aflatoxins, produced by Aspergillus fungi, are ubiquitous toxins and they can present a severe health risk to humans and animals if contaminated food and feed is consumed. Fungi live in the soil and on the surface of the crop and Aspergillus species are dominant in favorable conditions of maize cultivation areas. Climate change could threaten the production of safe food by promoting Aspergillus growth and aflatoxin production in food and feed. A novel biological approach using lactic acid bacteria (LAB) could reduce the health risks of aflatoxins through inhibiting mold growth, thus aflatoxin production and by binding existing aflatoxins. LAB are commonly used in fermented food production; they are also known to inhibit mold growth and interact with aflatoxins. LAB provide a potential novel approach to mitigate the mould growth and aflatoxin production in maize during storage and after food consumption. Mold growth inhibition by certain LAB strains may be caused by competition for resources between bacterial cells and fungi and/or production of antifungal compounds such as organic acids. Aflatoxin binding is more complex. Binding is a reversible reaction, which occurs on bacterial surfaces and involves interaction with carbohydrates, peptidoglycan and to some extent protein structures. Aflatoxin binding seems to be highly related to strain, matrix, temperature, pH, incubation time and related conditions. There are two different aspects of aflatoxin risk mitigation in this research. First is the fungal growth inhibition with LAB and second is aflatoxin binding from food and feed with LAB. We have isolated 200 strains of bacteria from 21 different indigenous fermented dairy and cereal products prepared locally in different parts of Kenya. Firstly, these strains are being tested for their growth inhibition abilities against aflatoxin producing Aspergillus fungi in laboratory conditions. Secondly, the same strains are tested for their abilities to bind and retain aflatoxin M1 and B1. Later, these same effective strains will be tested in various food and feed matrices against Aspergillus growth and then the ones with most potential will be identified. This approach aims at providing a safe method of reducing aflatoxin absorption in human gastrointestinal tract after ingesting fermented maize or dairy products, which are contaminated with aflatoxins. Novel biological methods can have a role in preventing toxic effects of aflatoxins in food and feed. Exploitation of LAB is a good option for existing methods as LAB are generally recognized as safe. This research is done as part of FoodAfrica programme, which is a research, and development programme and the main funding agency being Finnish Ministry for Foreign Affairs. The research is partnering with MTT Agrifood Research Finland and ILRI International Livestock Research Institute

Genomic methods in analyzing the communities of soil bacteria

Culture-independent examination of complex microbial communities has been made possible by recent advances in molecular biology. Terminal restriction fragment length polymorphism is one of such techniques that allow rapid assessment of the diversity of microbial community

The use of macroarray as a simple tool to follow the metabolic profile of Lactobacillus plantarum during fermentation

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Leuconostoc Strains Unable to Split a Lactose Analogue Revealed by Characterisation of Mesophilic Dairy Starters

Mesophilic starter cultures used in dairy industry have been traditionally characterised by metabolic and biochemical methods. As closely related species of lactic acid bacteria have often only minor differences in phenotypic traits, which may also be variable within certain species, clear identification is often complicated. Therefore, techniques of molecular biology have been applied for rapid detection and differentiation of lactic acid bacteria. In this work, some bacterial clones isolated from mesophilic starters, which were preliminary identified as lactococci by phenotypic methods, were found to be Leuconostoc strains by both PCR and PFGE. According to the results, genotypic differentiation methods used in combination with phenotypic tests provide a fast and convenient way to reliably identify lactic acid bacteria displaying atypical metabolic characteristics

Valorization of non-wood biomass - case studies with food industry side-streams and municipal foodwaste

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Viability of Lactobacillus paraplantarum DSM 14485 in human gastrointestinal tract and its molecular and biochemical identification after fermented vegetable consumption

Abstract In this study the viability of a potentially probiotic Lactobacillus paraplantarum DSM 14485 in the intestinal tract of 22 healthy test subjects was qualitatively assessed in a randomised double blinded cross-over study design lasting 2 x 4 weeks (interventions I and II) with a 4-week washout period. The subjects were given in their diet either spontaneously fermented vegetables (SF) or vegetables fermented by starter bacteria which contained  Lb. paraplantarum DSM 14485 (P). The numbers of lactic acid bacteria (LAB) in fecal samples were at the level of 105 cfu g-1 in both groups. The presence of Lb. paraplantarum DSM 14485 was confirmed by biochemical and molecular methods. We were able to show that Lb. paraplantarum DSM 14485, isolated from spontaneously fermented cucumbers, was viable in the intestine of ten test subjects after taking P-diet when the numbers of LAB were sufficiently high in the product