Background on the 'Lactoferrin' Molecule
The word ‘lactoferrin’ (‘lacto’ – means milk; ‘ferrin’ – means iron) denotes an iron-binding compound present in milk. However, Lactoferrin is also known to bind several other metals including copper, zinc, manganese, and vanadium. Lactoferrin is a 75 to 80-kDa metal-binding glycoprotein that is normally synthesized inside all mammals, including humans. It is a single-gene product (“bio-replenishment”) that is essential for life. Lactoferrin is present in sperm, amniotic/ seminal/ cerebrospinal/ gastric fluids, saliva, tears, vaginal secretions and other body fluids that bathe mucosal surfaces. It is also present in the white blood cells (neutrophils) and is localized in several tissues.
Each Lactoferrin protein molecule has the capacity to avidly bind two atoms of iron (and other metals) in a reversible manner. Based on its iron-binding status, the Lactoferrin molecule could exist in either ‘apo’ (iron-free) or ‘holo’ (iron-saturated) forms. The lactoferrin molecule could also exist (in a very low proportion), as a partially iron-saturated form, i.e. a single atom of iron bound to each molecule. All the three Lactoferrin forms are inter-convertible.
Lactoferrin is considered a multi-functional protein with a role in several important physiological pathways. The primary function of Lactoferrin is to play a role in supporting immunity and to help maintain a healthy physiology. It also has been demonstrated to have important roles in maintaining skeletal structure, supporting a healthy digestive system, and facilitating nutrient and mineral absorption.
Lactoferrin Bio-Functionality
LF Physiological Turnover
Lactoferrin is naturally produced and utilized in the body to support various functions. It is secreted in response to external stimuli – into the oral cavity (saliva/ crevicular fluid) and intestinal lumen (mucins/ gastric juices). Following the digestive process, any unabsorbed Lactoferrin is excreted in the feces while the absorbed Lactoferrin passes through the urine. Lactoferrin is also spent in the tears, exudates in skin during inflammation; in the seminal fluids in bone joints during exercise, and via via sperm and vaginal secretions during sex.
Immune Reinforcement
Lactoferrin interacts with specific receptors on blood cells (i.e. neutrophils, lymphocytes, monocytes and macrophages) and regulate several biochemical mediators of immune response. Lactoferrin avidly promotes to such immune cell cascade and helps in supporting the body's innate immunity.
The iron-chelating capacity of Lactoferrin in the metal-binding pockets in coordination with biocarbonate anion has been heavily researched for its role in reinforcing the natural defenses.
Bio-Replenishment
With external stresses and natural aging, levels of bioactive compounds (such as lactoferrin) begins to decline and can result in a deficiency or imbalance. In such instances, it becomes important to replenish the body’s reserves. This helps to keep the body healthy and energized. Simply gathering “helpful” ingredients and throwing them into a capsule is not enough - most bioactive compounds have multi-functional properties and must be extracted, isolated and activated in order to optimally perform their desired function.
Gastrointestinal Support
Lactoferrin has several physiological functions to protect the gastrointestinal tract. Approximately 80% of the immune system is located in the gut. Lactoferrin has been heavily studied for its ability to modulate the immune response and support probiotic activity. Lactoferrin has also been shown to stimulate cell proliferation in the gut, as well as help maintain digestive regularity. Lactoferrin has key receptors in the digestive tract; when taken in active form, this multi-functional protein can assist with nutrient and mineral absorption.
Prebiotic
Lactoferrin has been researched to show strong prebiotic activity. Probiotics,are beneficial good bacteria in the gut that help support digestive health and regularity. Prebiotics help lay down and support the environment in the gastrointestinal tract that allows these beneficial bacteria to survive and thrive. Most prebiotic compounds are insoluble sugars or fibers (inulin, FOS, etc.). Lactoferrin, in contrast, is a functional protein that elicits an iron-independent metabolic stimulation of probiotic flora which is a unique prebiotic activity.
Antioxidant
Oxidative stress is essentially an imbalance between the free radicals produced in the body and the ability of the body to counteract or detoxify their harmful effects through neutralization by antioxidants. The activity of most antioxidants (often plant source vitamins) is instantaneous; therefore, the functionality is not long lasting and may be limited. Lactoferrin, as an endogenous mammalian protein, has been shown to have a prolonged antioxidant activity of over 10 hours.
Commercial Applications of Lactoferrin
Due its numerous health benefits, Lactoferrin is widely used in nutritional/sports supplements worldwide. It is commonly found in infant formulas (particularly in South Asian counrties). Due to increasing and new research, Lactoferrin has also found unique applications in food safety, diagnostics, cosmetics, and even the veterinary market. Lactoferrin is considered safe and is an accepted nutritional ingredient by various government/ regulatory agencies, including the U.S. Food and Drug Administration (FDA), the European Food Safety Authority (EFSA), the New Zealand Food Safety Authority, and the Japanese Ministry of Health, Labor and Welfare (JMHLW).
Demand for Lactoferrin
As demand for Lactoferrin increases, need for efficient and effective procurement becomes key. Lactoferrin is largely harvested from cow's milk; however, different protein isolation techniques, as well as quality of the raw material, result in variance in Lactoferrin biological activity. Nonetheless, global production of Lactoferrin is currently estimated at 1,000 metric tons/year and this figure is continuously growing. Recent advances in Lactoferrin research elucidate structure-function relationships, anti-oxidant/ immuno-modulatory properties and cost-effective systems for large-scale protein isolation. This research has opened up unlimited opportunities for this bio-replenishment to be more extensively used in health industry.