The use of dietary fibre to optimize microbial gut function in pigs, with particular consideration of dietary cereal grains and legumes

This chapter examines interactions of dietary fibre components of pig diets with GIT microbiota, emphasizing cereals and legumes fed to pigs. Carbohydrate composition of these feedstuffs are described, and their relationship to metabolic activity of the porcine intestinal microbiota and interactions with the host. Fermentable carbohydrates which act as substrates for microbial metabolism are described, followed by an assessment of cereals and legumes as potential modulators of intestinal microbiota. Past work focussed on purified extracts, but attention is now focussing on whole grains or their fractions such as brans, in terms of effects on microbial populations. Such studies are showing the positive consequences of mixtures of DF in the form of complex plant cellular structures, rather than single refined ingredients, to achieve beneficial health outcomes. Further work is also needed to define appropriate quantities and types of DF to achieve desired effects whilst minimising negative outcomes.

The Influence of by-Products From Brewery Spent Grain Hydrolysis on Lactic Acid Fermentation Efficiency

The brewery spent grain (BSG) is a lignocellulosic waste material produced in a huge amount around the world. Strict environmental protection law requires proper utilization. BSG can be transformed into easy-fermentable carbohydrates as a result of hydrolysis. This may be a low-cost raw material for biotechnological fermentation. The literature provides a lot of information that hydrolysis of lignocellulose creates by-products which can be potentially noxious to bacteria cells employed in fermentation. This research examined the influence of most of these by-products: furfural, acetic, formic, gallic, and levuilnic acid, on the LA fermentation effectiveness. These components were introduced to Lactobacillus cultures in various concentrations. The rate of cell growth, glucose consumption, and lactic acid production were measured. This components affects in various extent on LA formation in the culture. In any case, there is a critical value of them harms the fermentation, due to the reduced ability of bacteria propagation. Lower concentrations of bio-catalyst lead to an LA production efficiency drop. The LA concentrations in flasks after one day of propagation with the 2.1 [g/L] of appropriate inhibitor drop app. [%] 16 (F), 22 (GA), 8 (LevA), 40 (AA), and 100 (FA) in comparison to the flask without any inhibitor.

Study of Carbohydrate Hydrolysis From Arracacha Roots (Arracacia Xanthorriza Bancroft) to Produce Fermentable Sugars

In Colombia, approximately 855 840 tons of arracacha are produced each year. The unsalable postharvest arracacha root (Arracacia xanthorriza Bancroft) is not commercialized, mainly due to mechanical damage or small and misshapen roots. In this work, dry samples were characterized and subjected to two treatments: one using thermal hydrolysis, applying saturated steam at pressures of 0,1034 MPa, 0,2068 MPa, and 0,4137 MPa; and another one using hydrolysis with sulfuric acid in concentrations between 0,252,00 M. Then, the cake resulting from the hydrolysis and filtration process was enzymatically hydrolyzed (Liquozyme SC DS, Novozymes) at 1,5, 5 and 10 KNU/g (pH 6, 80 _C, 2 h). Fermentation inhibitors (acetic acid and furfural) were evaluated in the best pretreatment. The results showed that the treatment with sulfuric acid at 1,00 M (2 h) has high yields in reducing sugars added to enzymatic hydrolysis. The maximum level of fermentable carbohydrates per gram of dry sample (1,04 g/g) was also reached. Regarding the fermentation inhibitors of the reducing sugar, a higher concentration of acetic acid was found with a lower furfural content. Therefore, arracacha discards are a promising raw material to increase the supply of bioethanol.

Fermentable carbohydrate metabolism in maguey mezcalero potosino (Agave salmiana): HPLC characterization and evaluation

The maguey mezcalero potosino (Agave salmiana) is a natural resource of great regional importance, used for the manufacture of mezcal and other alcoholic beverages by fermentation of simple sugars and sugars released by fructans hydrolysis. For this, only the stem and base of leaves is used, which results on wasting the other sections that represent up to 40% of weight of the complete plant. The objective of this study was to identify and quantify the fermentable carbohydrates present in raw and hydrolysed juices of the stem and four sections of the whole leaves (base, neck, wings and apex) of maguey plants with representative specimens of three stages of maturity with industrial importance. For carbohydrate characterization, high resolution liquid chromatography (HLPC) was used. The sugars found as fructose, glucose, sucrose, xylose and maltose coincide with those identified in other Agave species, significant differences are observed depending on the section and the state of maturity of the plant, the sugar concentration in the discarded sections of the plant (fructose: 5.79 – 4.80 mg mL-1) are considerable and statistically similar to those found in the stem (fructose: 2.49 mg mL-1) and the base of the leaf (fructose: 3.16 mg mL-1) (structure used in the mezcal production process). The results obtained can promote the integral use of the plant and diversification towards other industries such as pharmaceuticals, biofuels or foods.

Combined whole cell wall analysis and streamlined in silico carbohydrate-active enzyme discovery to improve biocatalytic conversion of agricultural crop residues

The production of biofuels as an efficient source of renewable energy has received considerable attention due to increasing energy demands and regulatory incentives to reduce greenhouse gas emissions. Second-generation biofuel feedstocks, including agricultural crop residues generated on-farm during annual harvests, are abundant, inexpensive, and sustainable. Unlike first-generation feedstocks, which are enriched in easily fermentable carbohydrates, crop residue cell walls are highly resistant to saccharification, fermentation, and valorization. Crop residues contain recalcitrant polysaccharides, including cellulose, hemicelluloses, pectins, and lignin and lignin-carbohydrate complexes. In addition, their cell walls can vary in linkage structure and monosaccharide composition between plant sources. Characterization of total cell wall structure, including high-resolution analyses of saccharide composition, linkage, and complex structures using chromatography-based methods, nuclear magnetic resonance, -omics, and antibody glycome profiling, provides critical insight into the fine chemistry of feedstock cell walls. Furthermore, improving both the catalytic potential of microbial communities that populate biodigester reactors and the efficiency of pre-treatments used in bioethanol production may improve bioconversion rates and yields. Toward this end, knowledge and characterization of carbohydrate-active enzymes (CAZymes) involved in dynamic biomass deconstruction is pivotal. Here we overview the use of common “-omics”-based methods for the study of lignocellulose-metabolizing communities and microorganisms, as well as methods for annotation and discovery of CAZymes, and accurate prediction of CAZyme function. Emerging approaches for analysis of large datasets, including metagenome-assembled genomes, are also discussed. Using complementary glycomic and meta-omic methods to characterize agricultural residues and the microbial communities that digest them provides promising streams of research to maximize value and energy extraction from crop waste streams.

A Study on Occurrence and Haemato-biochemical Alterations in SARA in Cattle Treated with Different Therapeutic Regimens

Background: Subacute ruminal acidosis is one of the most important nutritional diseases in cattle. The consequence of feeding excessive amounts of rapidly fermentable carbohydrates in conjunction with inadequate fiber to ruminants leads to subacute ruminal acidosis. Cattles are at a high risk of developing SARA. The present research work was undertaken to study haemato-biochemical alterations in SARA affected cattle treated with different treatment regimens. Methods: Present work was done to study the efficacy of sodium bicarbonate powder, Azadirachta indica (Neem) dried leaves powder and Saccharomyces cervisiae (Yeast) in sub-acute ruminal acidosis (SARA) in cattle. Out of 148 cattle screened, 24 (16.22%) were diagnosed as SARA, 13 (56.52%) animals were in mid stage of lactation followed by early and late lactation (5 cases, 21.74% each).Result: After sodium bicarbonate treatment, animals showed changes in various haemato-biochemical parameters. However decreased neutrophils and ALT was also observed. After treatment of Azadirachta indica reduction in lymphocyte and eosinophil count was seen.

Proximate composition and physico-chemical parameters of water hyacinth (Eicchornia crassipes) ensiled with breadfruit (Artocarpus altilis) as feed for WAD goats

Scarce forages and low digestibility are major challenges of dry season feeding of ruminants in the tropics. This can be overcome by conservation of forages through ensiling with unconventional and inexpensive materials containing high fermentable carbohydrates. Water hyacinth, an invasive water weed with high biomass yield was ensiled with graded levels of breadfruit and assessed for its potential as a feed resource. Breadfruit was included in silages at 0% (control, T1); 10% (T2), 20% (T3), 30% (T4) and 40% (T5) with sawdust added at a constant inclusion level of 10% to serve as absorbent. Proximate composition and silage quality assessment were determined after 30 days of ensiling. Results showed that dry matter (%) of silages ranged between 14.21 (T1) and 28.44 (T4). Ash contents (g/100g) reduced (P<0.05) as breadfruit inclusion increased in the silage diets. Crude protein (g/100g) was higher (P<0.05) in T1 (12.03) than T5 (9.18) but was similar in T2, T3 and T4 (10.50, 10.72, 10.28) respectively. The appearance, odour and texture of the silages in T3-T5 had acceptable physical attributes while pH values ranged from 4.65 – 5.40. It is concluded that the leaves and stem of water hyacinth ensiled with breadfruit have potential as feed for ruminants in terms ofnutritio nal and physico-chemical attributes.

Maize Silage Pretreatment via Steam Refining and Subsequent Enzymatic Hydrolysis for the Production of Fermentable Carbohydrates

Maize, also called corn, is one of the most available feedstocks worldwide for lignocellulosic biorefineries. However, a permanent biomass supply over the year is essential for industrial biorefinery application. In that context, ensiling is a well-known agricultural application to produce durable animal feed for the whole year. In this study, ensiled maize was used for steam refining experiments with subsequent enzymatic hydrolysis using the Cellic® CTec2 to test the application possibilities of an ensiled material for the biorefinery purpose of fermentable carbohydrate production. Steam refining was conducted from mild (log R0 = 1.59) to severe conditions (log R0 = 4.12). The yields were determined, and the resulting fractions were characterized. Hereafter, enzymatic hydrolysis of the solid fiber fraction was conducted, and the carbohydrate recovery was calculated. A conversion to monomers of around 50% was found for the mildest pretreatment (log R0 = 1.59). After pretreatment at the highest severity of 4.12, it was possible to achieve a conversion of 100% of the theoretical available carbohydrates. From these results, it is clear that a sufficient pretreatment is necessary to achieve sufficient recovery rates. Thus, it can be concluded that ensiled maize pretreated by steam refining is a suitable and highly available feedstock for lignocellulosic biorefineries. Ultimately, it can be assumed that ensiling is a promising storage method to pave the way for a full-year biomass supply for lignocellulosic biorefinery concepts.