Fermentation techniques in feed product

Zhaolai Dai , ... Guoyao Wu , in Animal Agriculture, 2020

Perspective and future directions

Feed fermentation is a complex process that integrates knowledge from nutrition, physiology, immunology, microbiology, biochemistry, industry pattern, ecology, economic system, and bioinformatics. The use of techniques for feed fermentation depends on the nutritional requirements and digestive physiology of animals, the nutritive value of feedstuffs, fermentation characteristics of the microorganisms added to the starter culture, and actual situations on private farms. Yet, it is not a small job to accurately determine the nutritional requirements of animals in the mail service-antibody era or the nutritive values of fermented feedstuffs due to differences in (a) the combinations of ingredients, (b) starter cultures, (c) additives to the biomass for fermentation, and (d) fermentation weather. One should conduct in heed that fermentation is required only for selected feedstuffs before they can be fed to animals in guild to prevent losses of nutrients. Standards should be fabricated for the evaluation of the nutritive values and for safety of the fermented feed products, and to provide official guidelines to regulate the employ of fermented feeds in animal agriculture. The spectrum and transfer of antibody-resistant genes in the microorganisms used for feed fermentation should be strictly monitored for the control of beast disease and the protection of human being wellness. The inclusion of functional bacteria of gut origin in starter cultures and in combination with other natural "regulators" of intestinal ecology may assistance to optimize fermentation processes. Finally, advancing cognition of metabolomics, the microbiome, bioinformatics and big information analyses will hasten development of fermented feeds for animal production, and this, in turn, will aid in sustaining animal agriculture in the mail service-antibiotic era.

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Lactic Acrid Bacteria

F. Mozzi , in Encyclopedia of Food and Wellness, 2016

LAB as Starter Cultures in the Food Manufacture

LAB, the so-called powerhouse or workhorse microbes of the fermented nutrient industry, are intensively employed in food and feed fermentation also as in nutrient biotechnology.

The ability of LAB to produce lactic acid from various sugars plays an important role in nutrient fermentation. As lactic acid derives from pyruvate (a glycolysis end product), a fast and desirable lactic acid production rate requires a loftier glycolytic flux. In add-on to lactic acid, other alternative end products such as ethanol, acetic acid, and formic acrid are formed past many species. LAB have the ability to ferment a variety of substrates from dairy, meat, vegetables, and cereals, transforming them into tasty products with unique textures and improved (longer) shelf lives. Depending on the raw material, specific, niche-adjusted LAB genera and species are employed to carry out fermentation to produce a variety of fermented foods and beverages such equally yogurts, fermented milks, buttermilk, kefir, cheeses, fermented sausages, fermented fish, sourdough, pickles, olives, sauerkraut, and other fermented vegetables and fruits. Examples of such fermented foods and beverages and the LAB involved are shown in Table ane .

Tabular array 1. Examples of fermented foods and beverages using LAB

Fermented foods and beverages LAB species
Dairy products
Yogurt Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus
Fermented milks Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus johnsonii, Lactobacillus reuteri
Kefir Lactobacillus kefir, Lactobacillus kefiranofaciens, Lactobacillus plantarum, Lactobacillus acidophilus, Lactobacillus kefiri
Buttermilk Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis var. diacetylactis
Cheeses Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Leuconostoc mesenteroides subsp. cremoris, Lactobacillus delbrueckii subsp. lactis, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus helveticus, Streptococcus thermophilus
Meat products
Fermented sausages Lactobacillus sakei, Lactobacillus curvatus, Pediococcus acidilactici
Fish products
Fermented fish Lactobacillus alimentarius, Carnobacterium piscicola
Vegetable products
Olives Pediococcus acidilactici, Pediococcus parvulus, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Lactobacillus plantarum, Lactobacillus pentosus
Sauerkraut Pediococcus pentosus, Leuconostoc mesenteroides, Lactobacillus plantarum
Leeks Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus sakei
Eggplant, mustard, beets, peppers, tomatoes, carrots, capers, cabbage Lactobacillus fermentum, Lactobacillus pentosus, Lactobacillus plantarum, Pediococcus pentosaceus, Lactobacillus brevis, Lactobacillus paracasei, Lactobacillus pantheris, Pediococcus acidilactici, Lactobacillus curvatus, Weisella consufa, Weisella soli, Enterococcus faecium
Soybeans Leuconostocs, Lactococcus lactis
Fermented fruits
Pineapples
  Kiwis
  Papayas
  Cherries		 Lactobacillus plantarum, Lactobacillus rossiae
Lactobacillus plantarum
Lactobacillus plantarum, Lactobacillus pentosus, Weisella confusa, Weisella cibaria
Lactobacillus plantarum, Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus pentosaceus
Alcoholic beverages
Vino Oenococcus oeni
Rice wine Lactobacillus sakei, Pediococcus acidilactici
Cereal-based products
Sourdough Lactobacillus sanfranciscensis, Lactobacillus farciminis, Lactobacillus fermentum, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus amylovorus, Lactobacillus reuteri, Lactobacillus pontis, Lactobacillus panis, Lactobacillus alimentarius, Pediococcus pentosaceus, Weisella cibaria
Fermented maize products Lactobacillus fermentum, Lactobacillus plantarum, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus helveticus, Lactococcus lactis subsp. cremoris

Despite the desirable role of LAB in food fermentation, some psychrotrophic species (i.eastward., Leuconostoc mesenteroides, Leuconostoc gasicomitatum, Lactobacillus curvatus, and Lactobacillus sakei) have been reported to cause detrimental effects in packaged (air, vacuum, and modified-temper) foods. Souring, foreign flavors, gas germination, discoloration, slime product, and decreased pH are some defects caused by the presence of this type of bacteria in ready-to-eat vegetable and fruit salads, fresh raw meat, cooked meat products, and composite foods.

Lactic starter cultures are defined as actively growing cultures of LAB that are used to start and command the fermentation process; in improver, these microorganisms contribute to the sensory characteristics of the fermented products and to their rubber. Fifty-fifty today, the almost relevant industrial application of LAB is their use as starter cultures in nutrient fermentation. Because the starter industry relies on the apply of selected strains of certain species with known metabolic backdrop, the use of starter cultures has undoubtedly improved the commercial and hygienic quality of the fermented final products and the standardization of the entire procedure. In dissimilarity, the limited number of available strains with high technological performance and the risk of bacteriophage attack results in the search for new strains to diversify products. In this respect, artisanal or homemade fermentations represent a rich source of indigenous LAB for commercial employ. Currently, defined, multi-, or mono-strain cultures prepared every bit frozen or freeze-dried cell concentrates are commercially available.

During the past few decades considering of the huge worldwide industrial marketplace for lactic fermentation (estimated equally more than 100 billion euros in 2011), especially in Western countries, many efforts have been made to improve the functioning of LAB as starter cultures or to ameliorate empathize their physiology for the production of industrially interesting metabolites. As a outcome, innovation is leading to the commercialization of more stress-tolerant, phage-resistant strains also as starter cultures that atomic number 82 to improved organoleptic properties. In this context, some metabolic traits of lactic starter cultures of technological involvement, such as product of aroma compounds, bacteriocins, exopolysaccharides (EPS), low-calorie sugars, and so on, have been the targets of research and volition be discussed afterwards in this article.

LAB metabolism results in both decreased carbohydrate content in the raw material they ferment and decreased pH acquired by lactic acid production. As mentioned before, this rapid acidification process is 1 of the about desirable effects of LAB growth, enabling the inhibition of detrimental microorganisms including several common human pathogens, and thus prolonging the shelf lives of fermented products. While lactic acid imparts a distinctive, desirable, and fresh acid taste to fermented products, the fermentation procedure must exist controlled to avoid excessive acid concentration, which may be rejected by consumers and may mask more than fragile flavors such as diacetyl. In cheese making, lactic acid production is also responsible for milk coagulation and texture properties. The pH decrease indirectly affects flavor by controlling the proteolytic activity of both coagulant and natural milk proteinases and by influencing the biochemical reactions involved in the formation of other aroma compounds. In this respect, LAB may heighten the organoleptic backdrop of the fermented product by imparting a characteristic flavor, which may derive from the fermentation of lactose or other sugars, citrate, the deposition of milk proteins and fat, and the metabolism of amino acids and free fatty acids. The flavor of the final product depends on several factors such every bit composition of the starter culture and raw material, type of fermentation, and ripening and storage conditions.

Besides the contribution of LAB to the season of fermented foods, some strains may contribute to the texture and nutritional quality of the final product. In addition, some LAB secrete natural nutrient preservatives because of the production of antifungal and antibacterial compounds such every bit boosted carboxylic acids (i.e., phenyl-lactic acid and acetic acid), fatty acids, ethanol, carbon dioxide, hydrogen peroxide, and bacteriocins.

Bacteriocin production is a desirable feature because they help control microbial populations in fermented foods and, thus, extend product shelf-life and condom. Bacteriocins produced by LAB are a diverse group of ribosomally synthesized antimicrobial peptides, which may be classified into different groups depending on the presence of posttranslational modifications and if they are active as unmarried- or two-peptide bacteriocins. Nisin is a broad spectrum bacteriocin, which inhibits Gram-positive foodborne pathogens and spoilage microbes besides as Gram-negative bacteria if combined with additional preventatives. Nisin has been the paradigm, the near studied and commercially applied bacteriocin to date. Narrow spectrum bacteriocins, such as lactococcin A, tin can also be of value as these bacteriocins have lytic issue on sensitive lactococci and may release key enzymes that can accelerate cheese ripening and enhance the development of important organoleptic properties. In food, bacteriocins may be present via in situ production by bacterial fermentation, past the addition of purified or semipurified preparations, or every bit an ingredient based on a fermentate of a bacteriocin-producing strain.

Sure LAB strains are able to produce EPS, which are polymers of carbohydrates. Depending on their chemic compositions, EPS can exist classified as homopolysaccharides, which contain a single type of monosaccharide, and heteropolysaccharides, which are formed from several repeating units of different monosaccharides. The power to synthesize EPS is widespread among LAB species; however, a wide diversity in respect to EPS structures and to the amount of polysaccharides produced exists amid the LAB producer strains. The inclusion of EPS-producing strains in starter cultures is desirable as these biopolymers naturally confer suitable technological characteristics to dairy products, such as improvement of rheological properties and reduction of syneresis of fermented milks as well every bit better consistency of curd in low-fatty ripened cheeses. In addition, health-promoting effects such as a possible part as prebiotics, serum cholesterol-lowering ability, and immunomodulatory and anticarcinogenic activities take been ascribed to EPS produced by LAB. Conversely, the presence of EPS in wine and beer is detrimental.

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Volume 4

Susann Mende , ... Doris Jaros , in Encyclopedia of Dairy Sciences (Third Edition), 2022

Introduction

Lactic acid bacteria (LAB) are ubiquitous in many different environments, including plants, the mucosal surfaces of humans, terrestrial, and marine animals, and fermented foods. LAB are traditionally used for food and feed fermentation to improve stability of the raw materials, sensory characteristics, and their nutritional value because of the product of lactic acid and other fermentation metabolites. A large number of strains are classified as beingness safe for use in foods, merely pathogenic species that may cause infections (some Streptococcus and Enterococcus spp.) or psychrotrophic LAB, which are able to grow even in cold storage, should likewise exist considered in the LAB grouping. Leaner associated with nutrient fermentations include Lactobacillus, Leuconostoc, Pediococcus, Lactococcus, and Streptococcus spp. Additional LAB with interesting species for the industry might be Weissella, Carnobacterium, Enterococcus, Oenococcus, and Tetragenococcus spp. Some of these are able to produce extracellular polysaccharides (EPS), which may exist interesting for applications in the food, pharmaceutical, and chemistry sectors. Commercially relevant EPS are, for example, xanthan produced past Xanthomonas campestris, gellan produced by Sphingomonas elodea, or curdlan produced by Alcaligenes faecalis. The only polysaccharide from LAB which is currently utilized commercially is a dextran from Weissella and Leuconostoc spp. Generally, the variety of EPS produced by LAB is large and offers significant potential for use in dissimilar industrial sectors (nutrient, health, chemical science, cosmetics).

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Sustainable livestock production and food security

Akash , ... Satish Adusumilli , in Emerging Issues in Climate Smart Livestock Production, 2022

Sustainable livestock production and surround

Increased global understanding of climate change and research showing that livestock is a correspondent to greenhouse gases, environmental destruction, and biodiversity depletion take contributed to a number of coordinated initiatives aimed at improving or maintaining the viability of livestock systems that provide economic and ecological resources without sacrificing future health and surround. Nutrient product and processing also as enteric feed fermentation contribute 45% and 39% of total agricultural emissions, respectively ( Steinfeld et al., 2006). Ruminants produce about 90% of livestock emissions through enteric fermentation (188 million tons), and the remaining 10% from manure (Swamy and Bhattacharya, 2006). Eutrophication, overgrazing, and soil deposition are some adverse environmental effects from inadequately managed livestock production systems. For example, a often cited statistic is that livestock contribute xviii% of greenhouse gases worldwide (Steinfeld et al., 2006). A recent metaanalysis of 86 studies that analyzed diverse agroforestry systems showed that when grassland was transformed into silvo-pastures mixing plants, forage, and livestock, the cyberspace aggregating of soil carbon or the sink of greenhouse gases was greater (Feliciano et al., 2018). Nutritional, genetic, wellness, and management strategies take been developed by brute scientists to reduce greenhouse gas emission intensities by as much as 30% (Gerber et al., 2013a,b). One of the main strategies for ensuring the sustainability of livestock production systems is the thought of sustainable diets that are competitive, ethically and socioculturally appropriate, and environmentally safe. In consideration of competitiveness amid feed and food systems, the principle of sustainable diets stipulates that potential feed systems will concentrate on the efficiency of the conversion of fibrous foods, such as residue of crops with a large content of poorly digestible structural carbohydrates (lignin and cellulose) into human-consuming animal products. Sustainable nutrient and feed systems thus accept the capacity to preserve the productivity of feed systems while at the aforementioned fourth dimension reducing their detrimental environmental and social effects (Bocquier and González-García, 2010).

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Microbial Production of Bioplastics from Renewable Resources

Jian Yu , in Bioprocessing for Value-Added Products from Renewable Resources, 2007

3.1.two scl-PHA synthesis past other strains

Alcaligenes latus is some other good strain for scl-PHA production, peculiarly for the homopolymer P3HB. Information technology accumulates P3HB up to fifty–60 wt% of dry prison cell mass from sucrose during cell growth, resulting in a relatively short fermentation fourth dimension on an culling carbohydrate [63]. In batch fermentation, the growth yield (Yx/due south) was effectually 0.4 thousand cell (g saccharide)−1 and the production yield (Yp/s) effectually 0.24 g P3HB (m sugar)−1 [64]. When prison cell growth was controlled under nitrogen-limited conditions, laboratory fermentation, fed with a high sucrose solution (900 thou L−1), reached a high productivity of 4.9 k P3HB L−1 h−ane and a yield of 0.42 g P3HB (g sucrose)−1 [65].

The PHA synthesis factor (phaCAB) of R. eutropha has been cloned and expressed in E. coli and Klebsiella strains in order to utilize other carbohydrates, such as sucrose [66, 67]. A productivity of 1 g PHA Fifty−1 h−ane was achieved with a recombinant Klebsiella on sucrose [67]. A high productivity of 2.8 g P3HB Fifty−ane h−1 in a fed-batch culture of a recombinant E. coli was too accomplished under vigorous agitation and oxygen-enriched aeration [68]. An E. coli harboring the A. latus P3HB cistron tin can produce P3HB on sucrose or P3HB3HV on sucrose and propionic acid, with PHA productivities similar to that of wild types [69, 70]. The precursor of 3-hydroxy valerate of copolymer P3HB3HV in the recombinant strain is formed from structurally related substrates, not through prison cell metabolism.

The 3HV precursor of P3HB3HV tin can likewise be supplied in vivo through cell metabolism on structurally unrelated substrates. A Pseudomonas sp. was cultivated on glucose to produce P3HB3HV in the absenteeism of propionic or valeric acids. In a fed-batch culture, the cell mass concentration reached 38 g L−1 in 45 h, containing 53 wt% P3HB3HV with 7.5 mol% 3HV. The productivity was around 0.84 yard PHA L−1 h−1 [71].

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Novel methods for pathogen control in livestock pre-harvest: an update*

T.R. Callaway , ... D.J. Nisbet , in Advances in Microbial Nutrient Safe, 2013

14.five.1 Probiotics

A probiotic is a 'alive microbial feed supplement which beneficially affects the host animal by improving intestinal microbial balance' and they are included in fauna rations to enhance performance or to reduce zoonotic pathogens (Collins and Gibson, 1999; Fuller, 1989; Sherman, 2009). Probiotics tin exist: (ane) live cultures of yeast or leaner, (ii) oestrus-treated (or otherwise inactivated) cultures of yeast or bacteria, or (3) fermentation finish products from culturing yeast or bacteria. The virtually common probiotic bacteria used in food animals remain Bifidobacterium and Lactobacillus (Gomes and Malcata, 1999).

In general, probiotics are aimed at improving brute growth and functioning, simply some have been reported to reduce foodborne pathogens in food animals (Ohya et al., 2000, 2001; Etienne-Mesmin et al., 2011; Leatham et al., 2009; Stephens et al., 2007a, 2007b). In swine, the addition of a probiotic culture comprising Streptococcus (Enterococcus) faecium reduced enterotoxigenic Eastward. coli (ETEC) colonization and subsequent diarrhea in swine (Underdahl et al., 1982; Ushe and Nagy, 1985). Inclusion of a Saccharomyces fermentation feed production did not reduce populations of Salmonella in experimentally infected pigs, but did reduce the negative effects of Salmonella infection in these animals (Price et al., 2010). Other swine studies plant that feeding a probiotic coupled with a prebiotic (a synbiotic, discussed beneath) reduced ETEC shedding and furnishings (Krause et al., 2010) besides as Clostridium difficile colonization (Songer et al., 2007). Other studies found that Lactobacillus and Streptococcus cultures reduced Salmonella populations in poultry (Zhang et al., 2007a, 2007b).

Research studies of ruminants have demonstrated that a probiotic containing Lactobacillus acidophilus cultures (single strain, known every bit a direct fed microbial or DFM) added to the feed of finishing cattle reduced E. coli O157:H7 shedding past more than l% (Brashears et al., 2003a, 2003b; Elam et al., 2003; Brashears and Galyean, 2002 ). In an contained evaluation, it was found that in cattle fed this DFM, fecal shedding of Due east. coli O157:H7 was 13%, while in the control group it reached 46% (Bribe et al., 2003). Further studies have confirmed that this product tin can reduce E. coli O157 populations in cattle (Stephens et al., 2007a, 2007b; Younts-Dahl et al., 2004; Moxley et al., 2003). Currently, this probiotic is fed to beef cattle to reduce pathogens and improve growth efficiency; this ensures that the pathogen reduction pays for its inclusion in the cattle ration, a disquisitional factor in whatsoever pathogen reduction strategy. Other probiotics comprising non-toxigenic Due east. coli strains that specifically target the reduction of Eastward. coli O157:H7 in ruminants have been developed also, and are in the production development stream (Zhao et al., 2003).

Drawbacks/limitations: Probiotics by definition need to exist fed daily, and there have frequently been problems with specific probiotic versus nutrition interactions, which must be examined for the nearly common diets.

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Zoonotic transfer of pathogens from animals to farm products*

D.J. Bolton , ... T.R. Callaway , in Global Safety of Fresh Produce, 2014

5.five.2 Pro-contest strategies

In the opposite manner to direct antipathogen strategies, pro-commensal strategies seek to promote the growth of groups of beneficial bacteria that are competitive with, or antagonistic to, pathogens. The use of native or novel microflora introduced to reduce pathogenic bacteria in the gut has been termed every bit a 'probiotic' strategy (Fuller, 1989). Providing a limiting nutrient ('prebiotic') to the microbial population that allows an existing commensal microbial population a competitive advantage in the alimentary canal is another pro-commensal approach. The overall goal of pro-competition strategies is to fill up all ecological niches in the gut and thereby forestall the establishment of, or cause the displacement of, a pathogenic bacterial population in the gut.

Probiotics are a 'live microbial feed supplement which beneficially affects the host animal by improving intestinal microbial balance' that are included in animate being rations to enhance performance, or to reduce zoonotic pathogens (Fuller, 1989). In full general, probiotics aim to improve animate being growth and functioning, only some accept been reported to reduce foodborne pathogens in food animals. In swine, the addition of a probiotic culture comprising Streptococcus (Enterococcus) faecium reduced enterotoxigenic E. coli (ETEC) colonization and subsequent diarrhea. Inclusion of a Saccharomyces fermentation feed product did not reduce populations of Salmonella in experimentally infected pigs, just did reduce the negative effects of Salmonella infection in these animals (Cost et al., 2010). Other studies take constitute that Lactobacillus and Streptococcus cultures reduced Salmonella populations in poultry.

Research studies in ruminants take demonstrated that a probiotic containing Lactobacillus acidophilus cultures fed to finishing cattle reduced E. coli O157:H7 shedding by more than 50%. Further studies have confirmed that this product can reduce E. coli O157 populations in cattle (Moxley et al., 2003). Currently, this probiotic is fed to beef cattle to reduce pathogens and amend growth efficiency; thus ensuring that the pathogen reduction economically pays for its inclusion in the cattle ration, a disquisitional gene in any pathogen reduction strategy to be implemented in the food production manufacture.

Prebiotics are substrates that are unavailable to or indigestible by the host beast, but are digestible by a portion of its microbial population. Prebiotics provide free energy or other limiting nutrients to the intestinal mucosa likewise as substrates for the intestinal bacterial fermentation, resulting in enhanced production of vitamins and antioxidants that further directly do good the host fauna (Kim et al., 2011). Some prebiotics can provide a competitive advantage to members of the native microflora that can help to exclude pathogenic bacteria from the intestine via direct competition for nutrients or for binding sites through the production of 'blocking factors', or antimicrobial chemical compound (east.g. bacteriocins, volatile fat acrid (VFA) production) (Price et al., 2010). Other research has indicated that specific carbohydrate prebiotics reduced colitis blazon symptoms and improved mucosal immunity in swine. In poultry, the use of prebiotics has been plant to increase immune measures and performance (Vandeplas et al., 2010), as well as to reduce Salmonella and Clostridium perfringens populations in broilers and models of in vitro intestinal infection (Kim et al., 2011).

Competitive exclusion (CE) involves the improver of a (non-pathogenic) bacterial culture to the abdominal tract of nutrient animals in order to reduce colonization or decrease populations of pathogenic bacteria in the gastrointestinal tract (Fuller, 1989). A CE culture may be composed of i or more than strains or species of leaner, but it should exist derived from the animal of interest and thus attempt to exploit relationships developed during co-evolution of host and microbiome. Salmonella colonization in young chickens was reduced past administration of a grooming of gut bacteria originating from healthy developed chickens. Other researchers have demonstrated that a swine mucosal CE civilization could reduce Salmonella populations in young pigs. Recent studies demonstrated that a swine CE culture derived from the cecal contents of salubrious pigs reduced the incidence of Salmonella cholerasuis and enterotoxigenic Eastward. coli. The utilize of true CE products in ruminants has been express because of the complexity of the ruminant gastrointestinal microbial population, and the length of time involved in cattle production (up to eighteen months).

The simultaneous application of probiotics or CE with prebiotics is known equally 'synbiotics', and could yield a synergistic issue in reduction of foodborne pathogenic bacterial populations in food animals prior to slaughter. Furthermore, synbiotic approaches increased glucose transport in broilers and increased the availability of B-vitamins. Several studies have demonstrated that synbiotic strategies could reduce postweaning E. coli diarrhea in swine and necrotic enteritis in poultry. In a variation on synbiotics, researchers included bacteriophages phages forth with a competitive exclusion civilisation to successfully reduce Salmonella population in poultry.

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Genomics and the Bioeconomy

Gerardo Jiménez-Sánchez , Jim Philp , in Genomics and Society, 2016

Fermenting industrial waste gases to bio-based products

Industrial waste gases, such as COii and CO, are starting to exist used as feedstocks for fermentation. This has the enormous advantage of decoupling bio-based production from food production. A good instance is the employ of steel mill off-gases, especially highly toxic CO, to produce valuable chemicals [93], and in the future, a jet fuel. Photosynthetic and nonphotosynthetic biocatalysts are existence developed that rely on metabolic engineering to improve yields and titers. Similarly, Calysta 17 of Kingdom of norway uses natural gas-fed fermentation to produce feed-quality protein with loftier nutritional value for use in aquaculture. There are 2 ways of carbon capture from waste matter gases for industrial purposes to consider, photosynthetic and nonphotosynthetic.

Photosynthetic carbon capture from waste matter gases

Much more attention has been given to photosynthetic processes and marine algal applications in particular. If successful, algae could deliver six to ten times more energy per hectare than conventional cropland biofuels while reducing carbon emissions by up to 80% relative to fossil fuels [94].

Cyanobacteria and algae grow faster than terrestrial plants and have simpler genetic backgrounds, which are easier to manipulate [95]. Despite the availability of a relatively large number of completed genome sequences, applications of synthetic biology in cyanobacteria and algae have significantly lagged behind those in East. coli and yeast.

Despite the obvious potential, in that location are several technical barriers and many articulate targets for synthetic biology studies [96]. There is a serious lack of chassis strains. There is a lack of cyanobacterial standardized parts, and it cannot be assumed that E. coli or yeast parts will perform the same way in blue-green alga (or vice versa). Indeed, performance will differ beyond different cyanobacterial species.

Transformation efficiencies need to be improved. In vivo brake activities are an important bulwark to introducing foreign DNA into cyanobacterial cells. A horizontal bulwark is that solar conversion efficiencies are low, with yields effectually v–7% during the growing season and effectually 3% in bioreactors on an annual footing [97]. In photo-bioreactors, excessive photon capture by the cells in the surface layer can block the calorie-free availability to the cells underneath [98]. Ribulose bisphosphate carboxylase is an essential enzyme in photosynthetic carbon fixation, just the reaction is deadening. However, the carbon fixation efficiency can exist greatly increased [99]. Despite early progress, synthetic biology in cyanobacteria and algae is in its infancy.

Nonphotosynthetic carbon capture from waste product gases

Microorganisms capable of fermenting syngas are ubiquitous. They have diverse metabolic capabilities, resulting in the formation of a variety of desirable native products such equally acetate, ethanol, butanol, butyrate, formate, and Hii [100] but non at industrial-scale efficiency. The vast majority of syngas fermenting organisms are anaerobic acetogens, which have a chemoautotrophic mode of metabolism [101].

Developing technologies based on purely chemoautotrophic organisms that utilize CO2 and other waste material gases for producing bio-based chemicals and fuels is attractive but technically very challenging. Half dozen natural carbon fixation pathways are known so far, of which v are found to some extent in chemoautotrophs. Of these, the Wood–Ljungdahl pathway seems to be the most efficient in bio-based product weather condition [102]. What may turn out to be disquisitional is that it as well can operate under heterotrophic weather [100].

The selection is similar to the choice in other bio-based production technologies—if contemplating the introduction of a complete carbon fixation pathway into a prokaryotic host, whether to innovate a natural pathway or a synthetic 1. And the dilemma is also the aforementioned—natural pathways take been optimized for the survival and reproduction of the native organisms in their natural environments, not for the survival in the artificial, extreme environs of a bioreactor, using high substrate concentrations to make loftier titers and yields of desired industrial products.

However, the task represents another classic for synthetic biological science. Carbon fixation requires a relatively big set of genes, most of which involve circuitous, largely unexplored regulation [103]. Then there are the familiar tasks, the creation and insertion of the genes necessary to make the industrial production and the removal of competing or interfering genes or pathways. Additional complications ascend from: anaerobic or microaerobic conditions; suitable redox environments; specialized metals chaperones; and membrane systems for ATP coupling [102]. All this likewise requires a constructed biology strategy that minimizes the complex regulatory systems. Every bit with many other bioeconomy applications of synthetic biology, the promise is great merely the tasks ahead gargantuan.

As examples of the hope, ethanol product from CO is considered to be a feasible arroyo to low-carbon fuel product, and at least three companies are seeking to develop the technology every bit a commercial process. The biochemistry and metabolic technology of gas fermentation for biofuels was reviewed recently [104]. Köpke et al. [105] demonstrated the production of ii,iii-butanediol from waste matter gases. A recent patent filing described the production of one or more terpenes past recombinant, acetogenic fermentation of CO [106].

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Brown Seaweeds

João Reboleira , ... Susana Bernardino , in Nonvitamin and Nonmineral Nutritional Supplements, 2019

Brown Seaweed equally a Food and Feed Supplement

The apply of extracts of chocolate-brown algae or their bioactive compounds as a food supplement is however a growing area, with a large number of studies focusing on in vitro potentials and the possible effects of their implementation on beast diet.

Walsh et al. (2013) investigated the influence of dietary supplementation of purified laminarin and fucoidan from Laminaria spp. independently or in combination on growth performance, coefficient of total tract apparent digestibility, selected faecal microbial populations, and volatile fatty acid concentrations in weaned pigs. The authors discovered that the inclusion of 300 mg/kg of laminarin showed the greatest benefit in growth operation with improvements in average daily gain and gain-to-feed ratio partially due to an increased coefficient of total tract apparent digestibility and lower faecal score. Curiously, combining fucoidan with laminarin showed no benign upshot on the overall growth performance of the weaned pigs. In another case, Hong et al. (2015) examined the furnishings of supplementing by-products from Undaria pinnatifida on ruminal fermentation characteristics in vitro as well as on growth operation, endocrine response, and milk product in Holstein cows (in vivo), and concluded that dietary supplementation with by-products from brown seaweed did not compromise ruminal fermentation nor daily milk yield and limerick, which may have potential to be used as a safe food supplement in dairy cows. More than recently, Belanche et al. (2016) studied the effect of 2 brown seaweeds (Ascophyllum nodosum and Laminaria digitata) on rumen function in rusitec fermenters and observed that these seaweeds had no substantial outcome on rumen fermentation, feed degradability, or methane emissions. Nonetheless, specific furnishings depending on species were noticed such as a substantial decrease in nitrogen degradability promoted by A. nodosum due to its high phlorotannin content, which led to a modify of bacterial community, having a negative impact. In contrast, 50. digitata did not accept these effects considering it has much lower phlorotannin content and therefore, promoted a greater efficiency of microbial protein synthesis. These results suggested that special attention must exist taken with seaweeds that present college phlorotannin concentrations.

It should still be mentioned that enquiry surrounding the potential of brown algae equally a source of bioactives for pharmaceuticals and food supplements for human consumption is existence carried out, and seems to be gaining pregnant traction. Lin et al. (2017) evaluated the combined effects of depression molecular weight fucoidan and fucoxanthin from S. hemiphyllum in terms of antihyperglycemic, antihyperlipidemic, and hepatoprotective furnishings in mouse models of type 2 diabetes. Positive effects in several of these activities, including lowered blood sugar and increased serum adiponectin levels were identified upon assistants of 300 mg/kg (of body weight) of low molecular weight fucoidan and fucoxanthin, as well as upon ingestion of a 50:50 mixture of these compounds. The mixture had a greater effect over increased hepatic glycogen levels and antioxidant enzyme activities, hinting at a synergic effect. Fan et al. (2017) evaluated the anticancer effects of a polysaccharide exclusively found in Sargassum fusiforme, and previously extracted by Cen et al. (2005) and Chen et al. (2012). In this written report, human hepatocellular carcinoma cells HepG2 were inoculated in mice supplied with a daily oral dose of 100, 200, and 400 mg/kg (of body weight) of the same polysaccharide. Significant in vitro HepG2 cytotoxicity was institute, besides as tumor growth inhibition in mice. The authors as well attributed the antitumor activity of this polysaccharide to possible immunomodulatory furnishings. In a airplane pilot study, Lee et al. (2012) studied the safety and effects of Seapolynol™, a commercial polyphenol excerpt obtained from Eastward. cava. In this study, 46 individuals with hypercholesterolemia were subjected to a 12-calendar week treatment period with a daily oral dose of 400 mg. The researchers verified a significant subtract in hip circumference, full cholesterol, low-density lipoprotein cholesterol, and c-reactive protein. No significant adverse effects were identified. Rhanasto-Rilla et al. (2017) performed an in vitro evaluation of the SIRT6 activation potential of extracts obtained from chocolate-brown seaweeds. These were obtained from Fucus dichitus, Fucus vesiculosus, Cytoseira tamariscofolia, Cytoseira nodacaulis, and Alaria esculenta. The activation of SIRT6 was evaluated through measurement of H3K9 deacetylation. Significant H3K9 deacetylation was verified in the presence of F. dichitus, F. vesiculosus, and C. tamariscofolia extracts. From the F. dichitus extracts, the researchers identified fucoidan as the compound responsible for the verified activities, using mass spectrometry. Yu et al. (2017) studied the neuroprotective effects of fucoxanthin from Sargassum horneri on HiiO2-induced toxicity, in SH-SY5Y cells and in cerebellar granule neurons. The authors verified significant protection confronting neural apoptosis and intracellular reactive oxygen species. Cells treated with fucoxanthin displayed higher survival rates and restored enzymatic activity, which had been disrupted by exposure to HtwoO2.

Based on the evaluated research, the employ of chocolate-brown seaweeds as dietary supplements appears to exist promising, even if there is a lack of human being studies. Farther studies are needed regarding the positive and negative impacts of dietary supplementation with extracts or pure compounds from brownish seaweeds under in vitro and in vivo weather condition in both humans and animals to understand their mechanisms of action and their true potential.

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Degradation of phenolic compounds institute in olive products by Lactobacillus plantarum strains

José María Landete , ... Rosario Muñoz , in Olives and Olive Oil in Health and Disease Prevention (2nd Edition), 2021

12.2 Phenolic compounds and Lactobacillus plantarum

L. plantarum is a versatile bacterium found in a variety of ecological niches, ranging from vegetable and found fermentations to the man gastrointestinal tract. 50. plantarum cells are rods with rounded ends, straight, generally 0.9–1.2   μm wide per iii–8   μm long occurring singly, in pairs, or in short chains (Fig. 12.i). The genome of the lactic acrid bacterium L. plantarum strain WCFS1 has been sequenced, 7 and its size of 3.three   Mb is among the largest known for lactic acid leaner. eight,9 Information technology is though that such genome length is related to the multifariousness of environmental niches in which Fifty. plantarum is encountered. Nonetheless, this bacterium is nigh often plant in the fermentation of plant-derived raw materials, which includes several industrial and artisan nutrient and feed fermentations, such as must, olives, and a variety of vegetable fermentations.

Figure 12.one. Manual electron micrograph of Lactobacillus plantarum CECT 748T grown in a defined media (12,000×).

The effects of olive phenolic compounds on Fifty. plantarum growth have been studied by several authors. Brines from nonalkali-treated green olives were tested for their antimicrobial properties against L. plantarum. ten They showed a marked bactericidal effect toward L. plantarum. Aqueous solutions of the total phenolics extracted from these brines had the aforementioned bactericidal effect. It has been demonstrated that diffused olive polyphenols exerted a significant inhibitory growth effect on L. plantarum during brining only when they were associated with NaCl. 4 The viability of L. plantarum in the presence of single or combined fractions of isolated phenolic compounds from NaOH-treated and untreated olive brines was studied. 11 When assayed at the concentrations founds in brines, only the single phenolic fraction containing hydroxytyrosol strongly inhibited L. plantarum. However, tyrosol, vanillic acid, verbascoside, and luteolin-seven-glucoside, when assayed equally single fractions, had no bactericidal result against L. plantarum. Similar results were obtained by evaluating inhibitory activities of p-hydroxybenzoic, sinapic, syringic, protocatechuic, and cinnamic acids on L. plantarum growth. 12 Hydroxytyrosol was the sole compound establish to be bactericidal at low concentration. eleven Nonetheless, in the same written report, the inhibitory combined result of some olive phenolics was also clearly demonstrated. 11

Several authors have studied the effects of oleuropein and its hydrolysis products on the survival of 50. plantarum. The results reported were different depending on the antibacterial exam method used. Oleuropein was bactericidal against L. plantarum strains isolated from green olive fermentations brines. 13 Heat-treated oleuropein likewise demonstrated a strong bactericidal event but not the brine-treated oleuropein, which allowed survival of most of the L. plantarum strains tested. In add-on, the inhibition of L. plantarum growth was always observed when oleuropein was associated with some other phenolic fraction or added direct in brines. Contrarily, it was besides reported that untreated oleuropein was not inhibitory to L. plantarum; however, when the aglycon was formed in the medium, cell viability decreased. 14 Moreover, when oleuropein and NaCl were associated, the bactericidal effect on L. plantarum growth was very pronounced. The aforementioned authors also reported that the presence of glucose seems to delay the antimicrobial activity of these ii compounds. 14

The bactericidal effect of oleuropein was accompanied by changes in the typical bacillary structure of L. plantarum. 13 The morphology of L. plantarum strains incubated in estrus-treated or untreated oleuropein solutions changes in both size and shape. Cells become longer, often deformed in their bacillary structure and also become wider. This could indicate that oleuropein promotes peptidoglycan disruption, which could atomic number 82 to cell death past destruction of the jail cell envelope. Information technology has been described that oleuropein increased the leakage of inorganic phosphate, glutamic acid, and potassium from Fifty. plantarum cells. 15 In improver, brines from nonalkali-treated green olives showed a marked bactericidal effect toward L. plantarum. 10 The bactericidal upshot was shown by sure alterations at ii unlike levels of the cellular ultrastructure, the cell wall, and the cytoplasmic membrane. Other changes in the cell ultrastructure were observed, such as the presence of mesosomal membranes. Fluorescence microscopy showed adsorption of phenolics to both whole cells and isolated jail cell walls from L. plantarum. These alterations maybe lead to the disruption of the prison cell envelope when the incubation time is extended, thus promoting cellular lysis. ten Recently, differential gene expression was used to increase the insights into the molecular mechanisms used by L. plantarum in the adaptation to oleuropein. 16 According to transcriptomic information, L. plantarum reduces growth, remodels membrane phospholipids, and diminishes the expression of several ABC transporters. The controlled expression of all of these molecular players suggests that oleuropein could act as a signaling molecule in the plant–microbe interaction and facilitate the adaptation of benign microbes such as Fifty. plantarum by the plant host, via controlled expression of bacterial molecular players involved in this reciprocal interplay. 16

The effects of dissimilar phenolic compound concentrations on the fatty acid limerick of 50. plantarum isolated from traditional homemade olive brines were determined. 17 They institute that phenolic compounds altered L. plantarum fatty acid constitution. When caffeic and ferulic acids were added to the medium, lactobacillic acid production was reduced at the expense of unsaturated fatty acids, mainly palmitoleic acid. Consequently, in stationary-phase cultures an increase in the degree of unsaturation was found. The authors suggest that acidic phenols could change the membrane fluidity, every bit a possible hypothesis for the changes observed in the unsaturated fat acid content. The fatty acid biosynthetic pathway was thoroughly downregulated at the transcriptional level in response to olive oil challenge. xviii A ready of 230 genes were differentially expressed by 50. plantarum to respond to olive oil. This response involved elements typical of the stringent response, as indicated by the induction of genes involved in stress-related pathways and downregulation of genes related to processes associated with rapid growth. A set of genes involved in the transport and metabolism of uniform solutes were downregulated, indicating that 50. plantarum does not require osmoprotective mechanisms in presence of olive oil. 18

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