Proteases in the diet of monogastric animals

There are many proteases, and about 2% of the human genome is involved in the regulation of their formation. The share of proteases involved in digestion accounts for only a small part. Despite this, the mechanisms of action of digestive proteases are less studied than carbohydrases and lipases. The incorporation of exogenous proteases into young animal feeds is often accompanied by improved utilization of protein and other nutrients. Exogenous proteases degrade inhibitors of the endogenous protease and lectins in feed. Alkaline proteases are of interest due to their broader substrate specificity and activity throughout the entire gastrointestinal tract. This group includes keratinases, which digest proteins inaccessible for cleavage by proteases and peptidases of animals. Keratinases digest agglutinins, glycinin and b-conglycinin and connective tissue proteins, which are resistant to the action of gastrointestinal enzymes and a number of exogenous proteases. The alleged reasons for the inconsistent results when using feed proteases are described. Their mediated positive effects not associated with proteolysis are indicated. It is advisable to use proteases with keratinolytic activity as fodder proteases.

Effects of Leucaena leucocephala supplementation to basal hay on Energy and Protein metabolism in West African. Dwarf sheep

Energy and protein utilization and quantitative retention of protein, fat and energy was investigated with twelve castrated West African Dwarf (WAD) sheep averaging (23.0 h 2.4 kg BW) in nitrogen and energy balance trials. Dried leaves of Leucaena leucocephala were offered as supplement at two levels 25% (diet 2) and 50% (diet 3) of dry matter intake (DM1), replacing hay in the basal hay diet. The basal hay diet without supplementation was the control. Measurements were performed by means of nitrogen and carbon balances and with the use of indirect calorimetry The digestibility and utilization of protein were influenced (P<0.05) by supplementation. Metabolisability of energy (ME/ GE) was on the average 42.9 (SEM 4.3)% being significantly (P<0.05) different among treatments. Diet 2 had a higher (P<0.05) retained protein (9.6 g/d) compared with the control diet and hence a superior (P<0.05) protein utilization than the control and diet 3, respectively. It was concluded that Leucaena leuccocephala improved protein utilization and retention in WAD sheep.

Nutrients Mediate Bioavailability and Turnover of Proteins in Mammals

As a major component of biologically active compounds in the body, proteins contribute to the synthesis of body tissues for the renewal and growth of the body. The high level of dietary protein and the imbalance of amino acid (AA) composition in mammals result in metabolic disorders, inefficient utilization of protein resources and increased nitrogen excretion. Fortunately, nutritional interventions can be an effective way of attenuating the nitrogen excretion and increasing protein utilization, which include, but are not limited to, formulating the AA balance and protein-restricted diet supplementing with essential AAs, and adding probiotics in the diet. This review highlights recent advances in the turnover of dietary proteins and mammal’s metabolism for health, in order to improve protein bioavailability through nutritional approach.

Comprehensive Resource Utilization of Waste Using the Black Soldier Fly (Hermetia illucens (L.)) (Diptera: Stratiomyidae)

The black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), is a saprophytic insect that can digest organic wastes, such as animal manure, plant residues, and food and agricultural wastes. In the degradation process, organic wastes are converted into protein, grease, and polypeptides, which can be applied in medicine, the refining of chemicals, and the manufacturing of feedstuffs. After their conversion by the H. illucens, organic wastes not only become useful but also environmentally friendly. To date, the H. illucens has been widely used to treat food waste and to render manure harmless. The protein and grease obtained via this insect have been successfully used to produce livestock feed and biodiesel. In this article, the biological characteristics, resource utilization of protein and grease, and environmental functions of the H. illucens are summarized. This article provides a theoretical basis for investigating potential applications of the H. illucens.

Current Trends in Protein Engineering: Updates and Progress

Proteins are one of the most important and resourceful biomolecules that find applications in health, industry, medicine, research, and biotechnology. Given its tremendous relevance, protein engineering has emerged as significant biotechnological intervention in this area. Strategic utilization of protein engineering methods and approaches has enabled better enzymatic properties, better stability, increased catalytic activity and most importantly, interesting and wide range applicability of proteins. In fact, the commercialization of engineered proteins have manifested in economically beneficial and viable solutions for industry and healthcare sector. Protein engineering has also evolved to become a powerful tool contributing significantly to the developments in both synthetic biology and metabolic engineering. The present review revisits the current trends in protein engineering approaches such as rational design, directed evolution, de novo design, computational approaches etc. and encompasses the recent progresses made in this field over the last few years. The review also throws light on advanced or futuristic protein engineering aspects, which are being explored for design and development of novel proteins with improved properties or advanced applications.