Last time we talked about Goat Colostrum, and this time we would like to talk about Lactoferrin.

In 1939, Sorensen Obtained a red protein while separating whey protein, and also obtained a partially purified red protein while separating Lp. However, it was named Lactoferrin till 1959 that Groves obtained the pure red substance by chromatography that this red substance was a glycoprotein bound with iron. The presence of Lactoferrin in human milk was discovered by scientists Montreuij and Johansonb in 1960. Subsequently, Baggin and other scientists found this protein in some body fluids and various cells and began a large number of studies. Studies have shown that Lactoferrin is a natural protein in animal milk. It is a multifunctional protein with broad-spectrum antibacterial and antiviral effects. It can regulate the iron balance in the body, regulate the generation of bone marrow cells, promote the growth of cells, regulate the immune function of the body, enhance the disease resistance ability of the body, inhibit the role of human tumor cells; It can cooperate with a variety of antibiotics and antifungal agents to treat diseases more effectively. ^[1]Because Lactoferrin has so many advantages, it can ultimately promote the body to improve immunity, and also the study of Lactoferrin has a long history, long use time, and good effect, so Lactoferrin is known as the elder of improving immunity.

(Overview of Lactoferrin)

Lactoferrin is widely distributed in mammalian milk and other tissues and their secretions, but the content of Lactoferrin in animal milk is the highest. Lactoferrin in the blood is mainly secreted by multinucleated cells, while bone marrow, salivary glands, and endometrium can also secrete a small amount of lactoferrin.^[2]

The average concentration of Lactoferrin in human milk is about 1.0-3.0mg/ml, and the content of Lactoferrin in milk is 0.02-0.35mg/ml. During lactation, the content of Lactoferrin changes with the lactation time. For example, the high value of Lactoferrin in human colostrum can reach 6-14mg/ml, and it can be reduced to 1 mg/ml in normal milk. The Lactoferrin content in bovine colostrum can reach 1 mg/ml on the first day after parturition, and then it begins to decrease. When the cows are at the end of lactation, the content of Lactoferrin in milk will rise again. ^[2]Because the concentration of Lactoferrin in milk is low and the process is very complex, about 14 liters of milk is needed to extract 1g Lactoferrin, so Lactoferrin is also known as the gold component in milk.

(Preciousness of lactoferrin)

Lactoferrin has a high affinity for iron ions, which is 250-300 times higher than that of transferrin. According to the difference of iron-binding, Lactoferrin can be divided into three types: iron deficiency, iron half-saturation, and iron saturation. Different types of Lactoferrin have different resistance to pasteurization heat denaturation, among which the iron saturated type has the strongest resistance, and the iron deficiency type has the weakest resistance. Lactoferrin can bind not only Fe³⁺ and Fe²⁺, but also Cu²⁺, Mn²⁺, Zn ²⁺.^[3]

(Mechanism of Lactoferrin)

As for the thermal stability of Lactoferrin, it was found that heat treatment at 72 ℃ for the 20s or 135℃ for 8s hardly affected the iron-binding capacity of Lactoferrin, but the iron-binding capacity of lactoferrin would be reduced if the time of treatment at the two temperatures was prolonged. The heat treatment intensity at 85℃ for 10 min did not affect the antibacterial activity of lactoferrin. Besides, some studies showed that Lactoferrin was degraded at 120℃ for 5min at ph2.0 or pH3.0, but the antibacterial activity of the degradation product was higher than that before treatment. This result led to the discovery of Lactoferrin active polypeptide. Lactoferrin has an antibacterial effect on Gram-positive bacteria and Gram-negative bacteria, but it has a stronger effect on Gram-negative bacteria. The iron saturation of Lactoferrin was negatively correlated with its antibacterial activity. The change of environmental pH affected the inhibitory effect of Lactoferrin on Gram-positive bacteria but had little effect on Gram-negative bacteria. When the pH was 7.5-8.0, the antibacterial effect was the best. The antibacterial activity of Lactoferrin was not affected after pasteurization under 70℃; the increase of HCO^3-concentration was beneficial to enhance its antibacterial activity.^[3]

Lactoferrin can respond to a variety of physiological and environmental changes, so it is considered to be a key component of the innate defense system. Lactoferrin has strong antibacterial activity against a variety of bacteria, fungi, yeasts, viruses, and parasites. It also has anti-inflammatory and anti-cancer activities and has a variety of enzyme functions. Lactoferrin plays a key role in maintaining the cellular iron level in vivo.^[4]

Lactoferrin has a significant relationship with respiratory health. In 2007, James C king, pediatrician, School of medicine, University of Baltimore, Maryland, USA Clinical studies by Dr. Jr and others have shown that: compared with infants without Lactoferrin intake, continuous Lactoferrin intake in term infants within 12 months after birth can reduce the average incidence of respiratory diseases (especially asthma) by 70%.^[5]

Lactoferrin has a significant relationship with intestinal health. In 2007, Professor Yoshio, from the Department of molecular microbiology and immunology, Department of biomedical science, Nagasaki University, Japan, showed that Lactoferrin had a significant inhibitory effect on rotavirus gastroenteritis, and the frequency and frequency of diarrhea and vomiting were significantly reduced. ^[6]

Lactoferrin is closely related to immunity, In 2017, Professor Timby N of the Department of clinical pediatric Sciences at the University of Mayo, Sweden, and expert professors from the von Horner children's Hospital at the University of Munich medical center and the Department of Nutrition at the University of California, Davis, showed that the average use of antipyretic drugs decreased by 42% after six months of life. ^[7]

Other research results of Lactoferrin in the expert consensus on the health effects of Lactoferrin on infants and young children were published by the Chinese Nutrition Society in 2018. The role of Lactoferrin includes: regulating immunity, enhancing the activities of monocytes and NK cells, and reducing the risk of cold during pregnancy. It can improve the bioavailability of iron in intestinal cells, stabilize the reduced iron ions, and reduce the stimulation of the gastrointestinal tract. Anti-inflammatory: reduce the release of inflammatory factors such as IL-1, IL-2, and TNF - α, and participate in the anti-inflammatory reaction. It can promote cell growth and reduce the incidence of necrotizing enterocolitis and delayed septicemia in premature infants. ^[8-9]reduce the incidence of respiratory tract infection in full-term infants, [9] reduce the number of intracellular types A streptococcus in tonsil samples of children with pharyngitis. ^[10]

[1]. Studies show that Lactoferrin added to milk powder is closer to breast milk. Research shows that lactoferrin in milk powder is closer to breast milk [citation date: 2020]
[2]. Isolation, preparation and study of lactoferrin. Cnki [reference date.2020]
[3]. Advances in the study of physical and chemical properties of lactoferrin and its recombinant expression system. Cnki [reference date.2020]
[4].Lactoferrin a Multiple Bioactive Protein: An Overview.NCBI [reference date.2020]
[5].King JC J, Cummings GE, Guo N, Trivedi L, Readmond BX, Keane V, et al. A double-blind, placebo-controlled, pilot study of bovine lactoferrin supplementation in bottle-fed infants. J Pediatr Gastroenterol Nutr. 2007;44(2):245-51.
[6].Egashira M , Takayanagi T , Moriuchi M , et al. Does daily intake of bovine lactoferrin-containing products ameliorate rotaviral gastroenteritis?[J]. Acta Paediatrica, 2010, 96(8):1242-1244.
[7].Hans D , Christine P , Niklas T , et al. Benefits of Lactoferrin, Osteopontin and Milk Fat Globule Membranes for Infants[J]. Nutrients, 2017, 9(8):817.
[8]. Yang Yuexin, Li Ning, Guidelines for The Application of Nutritional Functional Ingredients, A301 Lactoferrin[9].Manzoni,etal.Pediatrics.2012Jan;129(1):116-23
[10].Zuccotti,GV etal.Immune modulation by lactoferrin and curcumin in children with recurrentrespiratory infections.J Biol Regul Homeost Agents 2009;23(2):119-123.