This study aimed to evaluate technological (acidification, proteolysis, lipolysis, resistance to low pH, NaCl, and bile salts) and biopreservation (antimicrobial activity against foodborne pathogens) features of 1002 LAB by high throughput screening (HTS) methods. The LAB was isolated from 11 types of Brazilian artisanal cheeses (BAC) marketed in the main 5 producing regions. Remarkable intra-species variability in acidification rates have been found, which was most pronounced between isolates from Mina's artisanal cheeses, Caipira and Coalho cheeses. Lacticaseibacillus paracasei and Levilactobacillus brevis showed the fastest acidification rate; however, all isolates showed slower acidification rates than a lactococcal control strain (4.3 × lower). When testing inhibitory effects, > 75% of LAB isolates could inhibit the growth of Staphylococcus aureus ATCC 19095 and Listeria monocytogenes ATCC 7644. Two of these isolates, identified as Lactiplantibacillus plantarum and Lentilactobacillus buchneri, the sterile and neutral supernatants alone, were sufficient to inhibit L. monocytogenes growth. Principal component analysis (PCA) allowed the identification of functional groups based on proteolytic and lipolytic activity, osmotic stress resistance, and inhibition of L. monocytogenes. The type of cheese the isolates were recovered from influenced properties such as anti-listerial compounds and lipolytic enzyme production. The use of HTS and multivariate statistics allowed insights into a diverse set of LAB technological and biopreservation properties. These findings allow a profound knowledge of the heterogeneity of a large set of isolates, which can be further used to design starter cultures with varied and combined properties, such as biopreservation and technological features. Besides that, HTS makes it possible to analyze a vast panel of LAB strains, reducing costs and time within laboratory analysis, while avoiding the loss of information once all LAB are tested at the same time (differently from the traditional labor-intensive approach, in which a few numbers of strains is tested per time).
DOCUMENT
Managing dairy excreta as slurry can result in significant emissions of ammonia (NH3) and greenhouse gases (GHGs) during storage and thereafter. Additionally, slurry often has an imbalanced nitrogen (N) to phosphorus (P) ratio for crop fertilization. While various treatments exist to address emissions and nutrient imbalances, each has trade-offs that can result in pollution swapping. An integrated management system, starting with source segregation (SS) in-house to separate faeces and urine into two manageable streams followed by step-wise complementary treatments has been designed to manage nutrients and reduce emissions in the whole chain, but its effect on emissions in storage remains untested. This study investigated NH3, nitrous oxide (N2O), and methane (CH4) emissions and total N losses from integrated storage systems combining SS, mesophilic or thermophilic anaerobic digestion (AD), acidification, drying and zeolite addition and an impermeable cover. These systems were compared to two reference slurry storage systems: in-house uncovered (US) and outside covered (CS). A 30-day lab-scale experiment was conducted at 10 °C, monitoring emissions using an INNOVA1412 gas analyser, while total N losses were assessed using mass balance. Results indicated that the SS fractions treated before covered storage exhibited significantly lower emissions (NH3 or CH4 or both) compared to both reference slurry storage systems (US and CS). Source segregation combined with acidification of urine and AD of faeces at 35 °C and an impermeable cover allowed for a 99% reduction in NH3 emissions, a 45% reduction in CH4 emissions and had no effect on N2O emissions as compared to US. When AD of faeces was conducted at 55 °C instead of 35 °C, the CH4 emission was reduced by 77% compared to US. This study concludes that SS combined with urine and faeces treatment allows a more effective and simultaneous reduction of all emissions in storage as compared to slurry storage systems, while also effectively separating nutrients allowing more precise N and P fertilization with dairy excreta. Further research is necessary to assess emissions and fertilizer value of treated fractions after field application, in addition to the associated costs.
LINK
This open access book states that the endemic societal faultlines of our times are deeply intertwined and that they confront us with challenges affecting the security and sustainability of our societies. It states that new ways of inhabiting and cultivating our planet are needed to keep it healthy for future generations. This requires a fundamental shift from the current anthropocentric and economic growth-oriented social contract to a more ecocentric and regenerative natural social contract. The author posits that in a natural social contract, society cannot rely on the market or state alone for solutions to grand societal challenges, nor leave them to individual responsibility. Rather, these problems need to be solved through transformative social-ecological innovation (TSEI), which involves systemic changes that affect sustainability, health and justice. The TSEI framework presented in this book helps to diagnose and advance innovation and change across sectors and disciplines, and at different levels of governance. It identifies intervention points and helps formulate sustainable solutions for policymakers, administrators, concerned citizens and professionals in moving towards a more just and equitable society.
MULTIFILE
Microbes like bacteria and fungi can grow on almost everything, including e.g. on a music CD made of aluminum and polycarbonate. How? By producing an optimal mixture of effective enzymes that degrade the material on which the microbes thrive. In this project we want to find and characterize microbes that have the ability to digest one of the most commercially successful but at the same time hard-to-degrade materials: furan-based bio-composite resin. To help the microbes to degrade this recalcitrant material, we first must open up the complex resin structure by using (mild) acidification, grinding, and/or UV light. Thus, with this project we aim to find an effective and sustainable way to safely and effectively dispose and recycle used bio-composite resins. Our findings will help to increase the circularity of bio-composite materials and as such decrease the environmental waste pressure.
