576
Bacteroidetes or Firmicutes while it promotes the growth of Salmonella and Shigella
pathogens (Khan et al. 2012; Mach and Clark 2017).
Dietary proteins provide different amino acids which influences the host metabolisms and promote the gut microbiota growth and diversity, and undergo microbial
fermentation to produce secondary metabolites such as bioamines, fatty acids and
other nitrogen containing compounds (Lin et al. 2017). Fan et al. (2017) observed
decrease in bacterial population in ileum, reduction of protein concentration and
decrease in the concentration of metabolites such as SCFAs and bioamines. A consumption of diet low in Microbiota–accessible carbohydrates (MACs) or dietary
fiber has been associated with reduction of gut microbiota diversity which results in
development of colon cancer, diabetics, inflammatory and cardiovascular diseases
(Holmes et al. 2011; Makki et al. 2018). A low fiber diet with abundance of
Bacteroides levels, results in lower production of SCFAs (Chen et al. 2017). Some
species of Bacteroides such as B. fragilis moreover cause diarrhea, inflammatory
bowel diseases and gastrointestinal disorder (Wexler 2007). Recently, a study
resulted in the richness of microbiota in the 15% crude protein diet along with the
increase in the abundances of beneficial Lactobacillaceae, Actinomycetaceae, and
Micrococcaceae (Chen et al. 2018).
25.5 Bioavailability of Nutrients
Bioavailability of desired nutrients to the cells from the gut plays a critical role for
performing normal physiological functions (Fairweather–Tait 1997; Krebs 2001;
Schönfeldt et al. 2016). Nutrient utilization is affected by a sequence of metabolic
activities like uptake, solubilization, and enzyme secretion, enzymatic transformation, digestion, release, absorption and excretion. The bioavailability of macronutrients like carbohydrates, proteins, and fats, is generally higher (> 90%) than the
micronutrients like vitamins, minerals, and bioactive phytochemicals such as flavonoids, carotenoids etc., and is dependent upon the amount of food digested, absorbed
and/or utilized by the body. Thus, the supply of nutrients and non–nutrient bioactive
compounds to the human body largely depends on both the amount in food and their
bioavailability.
Bioavailability depends on many factors like age, gender, genetics, tissue uptake,
nutritional status, physiological factors like gastric acid secretion, food matrix, and
interactions between nutrients in the presence of enhancers and inhibitors in the diet
(Davidsson and Tanumihardjo 2013; Yetley 2007). Some environmental factors like
sunlight, wavelength of light in artificial environments, pH of the soil, fertilizer
usage, degree of ripeness at harvest, and morphological source (stem, leaf, flower,
or fruit), impact the character of nutrients and their bioavailability from plants. Food
processing factors like thermal treatments, homogenization, lyophilization, cooking
(boiling, frying, steaming), storage, mechanical treatments (grating, cutting, chopping, slicing, mashing, and juicing), also impact the bioavailability of nutrients from
K. Sharma et al.
Bacteroidetes or Firmicutes while it promotes the growth of Salmonella and Shigella
pathogens (Khan et al. 2012; Mach and Clark 2017).
Dietary proteins provide different amino acids which influences the host metabolisms and promote the gut microbiota growth and diversity, and undergo microbial
fermentation to produce secondary metabolites such as bioamines, fatty acids and
other nitrogen containing compounds (Lin et al. 2017). Fan et al. (2017) observed
decrease in bacterial population in ileum, reduction of protein concentration and
decrease in the concentration of metabolites such as SCFAs and bioamines. A consumption of diet low in Microbiota–accessible carbohydrates (MACs) or dietary
fiber has been associated with reduction of gut microbiota diversity which results in
development of colon cancer, diabetics, inflammatory and cardiovascular diseases
(Holmes et al. 2011; Makki et al. 2018). A low fiber diet with abundance of
Bacteroides levels, results in lower production of SCFAs (Chen et al. 2017). Some
species of Bacteroides such as B. fragilis moreover cause diarrhea, inflammatory
bowel diseases and gastrointestinal disorder (Wexler 2007). Recently, a study
resulted in the richness of microbiota in the 15% crude protein diet along with the
increase in the abundances of beneficial Lactobacillaceae, Actinomycetaceae, and
Micrococcaceae (Chen et al. 2018).
25.5 Bioavailability of Nutrients
Bioavailability of desired nutrients to the cells from the gut plays a critical role for
performing normal physiological functions (Fairweather–Tait 1997; Krebs 2001;
Schönfeldt et al. 2016). Nutrient utilization is affected by a sequence of metabolic
activities like uptake, solubilization, and enzyme secretion, enzymatic transformation, digestion, release, absorption and excretion. The bioavailability of macronutrients like carbohydrates, proteins, and fats, is generally higher (> 90%) than the
micronutrients like vitamins, minerals, and bioactive phytochemicals such as flavonoids, carotenoids etc., and is dependent upon the amount of food digested, absorbed
and/or utilized by the body. Thus, the supply of nutrients and non–nutrient bioactive
compounds to the human body largely depends on both the amount in food and their
bioavailability.
Bioavailability depends on many factors like age, gender, genetics, tissue uptake,
nutritional status, physiological factors like gastric acid secretion, food matrix, and
interactions between nutrients in the presence of enhancers and inhibitors in the diet
(Davidsson and Tanumihardjo 2013; Yetley 2007). Some environmental factors like
sunlight, wavelength of light in artificial environments, pH of the soil, fertilizer
usage, degree of ripeness at harvest, and morphological source (stem, leaf, flower,
or fruit), impact the character of nutrients and their bioavailability from plants. Food
processing factors like thermal treatments, homogenization, lyophilization, cooking
(boiling, frying, steaming), storage, mechanical treatments (grating, cutting, chopping, slicing, mashing, and juicing), also impact the bioavailability of nutrients from
K. Sharma et al.