Prebiotic peptides, their formation, fermentation in the gut, and health implications

Prebiotics can be synthesized from sources other than dietary fibers, such as proteins. The proteins, when processed into peptides have healthful or deleterious effects on the host. Outside living systems, prebiotic peptides (PP) are formed via preformation of amino acids or related monomeric building blocks, resulting in nonenzymatic polymerization/ligation to produce peptides. Whereas, inside living systems like the human gut, many metabolic pathways are involved in PP production, and mostly involve host-microbiota interactions. The interplay is responsible for PP activities and their implications on host amino acid balance and metabolism. Similar to carbohydrates fermentation, PP will yield short chain fatty acids (SCFA), but also branched chain fatty acids (BCFAs), phenols, indole, hydrogen sulfide, amines, and ammonia, capable of biologically mediating molecular signals. This holistic review considers a brief description of prebiotics, and tracks down prebiotic peptides formation processes, interactions with gut microbes, and health outcomes.

Prebiotics in vitro digestion by gut microbes, products' chemistry, and clinical relevance

Several investigations have elucidated the chemistry of prebiotics based on their fermentation by the colonic microbes, which release metabolites that are often implicated in host's gut and whole body health. The present study aims at providing a preview of prebiotics and their interactions with the colonic microbiota for a slow fermentation in vitro. The metabolites produced, mainly short chain fatty acids (SCFA), their chemistry, interactions with prebiotic structural mechanisms, and beneficial impacts on the host were also reported. The present review further considers the clinical relevance of the SCFAs produced. It was deduced that the physicochemical properties of prebiotics would influence their colonic fermentation rate, microbial choice, and growth as well as SCFA type and ratios. This will in turn be of utmost clinical significance. KEY POINTS: • Prebiotics affect the composition of gut microorganisms. • The chemistry of short chain fatty acids are described. • Microbial and clinical applications of SCFAs were provided.

Perspectives on the trends, challenges and benefits of green, smart and organic (GSO) foods

Rapid rate of industrialization has turned our planet around in favor of fast foods, food fraud, food terrorism, food waste, food adulteration, food poisoning, food contamination and food injustice, paving the path for green, smart and organic products. Green foods are grown and harvested in the absence of any form of environmental pollution or harmful conditions. Smart foods are termed to be good for the consumers, farmers and the planet. Organic foods are regarded as “credence goods” because some of the attributes that consumers may consider are neither obvious nor easily verified. Therefore, these three terms are interconnected as they forge a substantive common denominator - healthfulness. The concepts of green, smart and organic (GSO) foods are herein recounted together with their interdependence and relationship to health and sustainability. The processes, policies and global trends of GSO foods were discussed, whilst not undermining the benefits and challenges associated with them.

Fermentation of prebiotics by human colonic microbiota in vitro and short-chain fatty acids production: a critical review

Prebiotics are known for their health benefits to man, including reducing cardiovascular disease and improving gut health. This review takes a critical assessment of the impact of dietary fibres and prebiotics on the gastrointestinal microbiota in vitro. The roles of colonic organisms, slow fermentation of prebiotics, production of high butyric and propionic acids and positive modulation of the host health were taken into cognizance. Also, the short-chain fatty acids (SCFAs) molecular signalling mechanisms associated with their prebiotic substrate structural conformations and the phenotypic responses related to the gut microbes composition were discussed. Furthermore, common dietary fibres such as resistant starch, pectin, hemicelluloses, β-glucan and fructan in context of their prebiotic potentials for human health were also explained. Finally, the in vitro human colonic fermentation depends on prebiotic type and its physicochemical characteristics, which will then affect the rate of fermentation, selectivity of micro-organisms to multiply, and SCFAs concentrations and compositions.

The quadriceps gastrocnemius muscle

The gastrocnemius muscle forms the belly of calf muscles in the posterior compartment of the leg. This paper reports a four-headed gastrocnemius (named quadriceps gastrocnemius) muscle as a new variant and when present can alter the anatomy and/or the boundaries of the popliteal fossa. The four heads are named as medial, intermedio-medial, intermedio-lateral and medial. The newly identified heads, intermedio-medial and intermedio-lateral heads form the inferior boundaries of the popliteal fossa. Clinical conditions like popliteal entrapment syndrome may arise because of distal fossa congestion created by the intermedio-medial and intermedio-lateral heads. This supernumerary heads may also be useful for grafting and they also provide bulkier mass for gastrocnemius proximal attachment. The knowledge of anatomical variants presented is useful to surgeons, prosectors and radiologists.

Multiple abdominal peritoneal and intestinal variations and their accompanying clinical implications

Accessory peritoneal sac and cystoduodenal ligament as peritoneal variations were observed in a cadaver in our laboratory. Slender stomach, thin transverse colon, redundant sigmoid colon, absent ascending colon and doubly distended gall bladder were also reported in the same cadaver. Relevant anatomical and clinical implications are discussed.