Perspective: A proposal on solutions of modern supply chain construction for lactoferrin

Lactoferrin is an iron-binding glycoprotein of the transferrin family that is found in most bodily fluids of mammals and has a variety of biological and beneficial functions, with great importance in health enhancement as a supplement for humans and other animals. More than 300 t of lactoferrin were produced in 2021, and this number is expected to grow yearly by 10% to 12%, to over 580 t in 2030. With new and important functions of lactoferrin being revealed and studied, focus on its industrial production and application is increasing accordingly. However, lactoferrin is mainly sourced from cheese whey or skim milk by cation-exchange column chromatography, which is a costly and low-quality method. A potential solution for lactoferrin global supply chain construction is proposed in this article as a complement to traditional routes of purification from whey or skim milk. The large-scale production of lactoferrin, mainly by recombinant yeast, mammal, and grain systems, as well as the market niche and product design, are discussed.

Lactoferrin and Its Derived Peptides: An Alternative for Combating Virulence Mechanisms Developed by Pathogens

Due to the emergence of multidrug-resistant pathogens, it is necessary to develop options to fight infections caused by these agents. Lactoferrin (Lf) is a cationic nonheme multifunctional glycoprotein of the innate immune system of mammals that provides numerous benefits. Lf is bacteriostatic and/or bactericidal, can stimulate cell proliferation and differentiation, facilitate iron absorption, improve neural development and cognition, promote bone growth, prevent cancer and exert anti-inflammatory and immunoregulatory effects. Lactoferrin is present in colostrum and milk and is also produced by the secondary granules of polymorphonuclear leukocytes, which store this glycoprotein and release it at sites of infection. Lf is also present in many fluids and exocrine secretions, on the surfaces of the digestive, respiratory and reproductive systems that are commonly exposed to pathogens. Apo-Lf (an iron-free molecule) can be microbiostatic due to its ability to capture ferric iron, blocking the availability of host iron to pathogens. However, apo-Lf is mostly microbicidal via its interaction with the microbial surface, causing membrane damage and altering its permeability function. Lf can inhibit viral entry by binding to cell receptors or viral particles. Lf is also able to counter different important mechanisms evolved by microbial pathogens to infect and invade the host, such as adherence, colonization, invasion, production of biofilms and production of virulence factors such as proteases and toxins. Lf can also cause mitochondrial and caspase-dependent regulated cell death and apoptosis-like in pathogenic yeasts. All of these mechanisms are important targets for treatment with Lf. Holo-Lf (the iron-saturated molecule) can contain up to two ferric ions and can also be microbicidal against some pathogens. On the other hand, lactoferricins (Lfcins) are peptides derived from the N-terminus of Lf that are produced by proteolysis with pepsin under acidic conditions, and they cause similar effects on pathogens to those caused by the parental Lf. Synthetic analog peptides comprising the N-terminus Lf region similarly exhibit potent antimicrobial properties. Importantly, there are no reported pathogens that are resistant to Lf and Lfcins; in addition, Lf and Lfcins have shown a synergistic effect with antimicrobial and antiviral drugs. Due to the Lf properties being microbiostatic, microbicidal, anti-inflammatory and an immune modulator, it represents an excellent natural alternative either alone or as adjuvant in the combat to antibiotic multidrug-resistant bacteria and other pathogens. This review aimed to evaluate the data that appeared in the literature about the effects of Lf and its derived peptides on pathogenic bacteria, protozoa, fungi and viruses and how Lf and Lfcins inhibit the mechanisms developed by these pathogens to cause disease.

A ratiometric electrochemiluminescence resonance energy transfer platform based on novel dye BODIPY derivatives for sensitive detection of lactoferrin

A ratiometric electrochemiluminescence resonance energy transfer (ECL-RET) platform depended on novel dye BODIPY derivatives was proposed for rapid detection of lactoferrin. This ECL-RET platform is composed of aptamer decorated BODIPY composites and C₆₀@BSA, in which BODIPY derivative is the ECL probe and can generate significant resonance energy transfer with K₂S₂O₈. BODIPY derivative and K₂S₂O₈ are used as built-in reference signal and calibration signal respectively to eliminate background signal and abnormal change signal by double signal self-calibration process. At the same time, C₆₀, as the accelerator of K₂S₂O₈, can effectively increase the ECL signal and further transfer as much energy as possible to BODIPY derivative. Under optimal conditions, the constructed ECL-RET platform exhibited sensitive detection of lactoferrin in the wide linear range of 10^-4- 850 ng/mL with a LOD of 42 fg/mL. Meanwhile, the proposed ECL-RET aptasensor demonstrated superior stability, specificity and reproducibility, displaying favorable application value in practical diagnosis of this method.

In Silico and In Vitro Analysis of Multifunctionality of Animal Food-Derived Peptides

Currently, the associations between oxidative stress, inflammation, hypertension, and metabolic disturbances and non-communicable diseases are very well known. Since these risk factors show a preventable character, the searching of food peptides acting against them has become a promising strategy for the design and development of new multifunctional foods or nutraceuticals. In the present study, an integrated approach combining an in silico study and in vitro assays was used to confirm the multifunctionality of milk and meat protein-derived peptides that were similar to or shared amino acids with previously described opioid peptides. By the in silico analysis, 15 of the 27 assayed peptides were found to exert two or more activities, with Angiotensin-converting enzyme (ACE) inhibitory, antioxidant, and opioid being the most commonly found. The in vitro study confirmed ACE-inhibitory and antioxidant activities in 15 and 26 of the 27 synthetic peptides, respectively. Four fragments, RYLGYLE, YLGYLE, YFYPEL, and YPWT, also demonstrated the ability to protect Caco-2 and macrophages RAW264.7 cells from the oxidative damage caused by chemicals. The multifunctionality of these peptides makes them promising agents against oxidative stress-associated diseases.

Expression and characterization of recombinant human lactoferrin in edible alga Chlamydomonas reinhardtii

Lactoferrin (LF) is a naturally occurring iron-binding glycoprotein with a variety of biological functions. It has increasing demand every year and huge market potential. In this study, we explored the feasibility of expressing human LF (hLF) in edible algae C. reinhardtii. A codon-optimized hLF gene was synthesized, inserted into pCAMBIA-1301C and transformed into C. reinhardtii SP strain. In total, 7 hLF-expressing clones were selected with clone 121 exhibiting the highest expression level. The hLF-containing algal extract significantly inhibited the growth of bacteria such as Escherichia coli and Klebsiella variicola. During acute toxicity experiment no acute toxicity was detected, especially on changes of the body weight and histopathology of organs. The recombinant hLF possessed a similar or modestly reduced stability compared to commercial hLF standard. Our data indicated that expression of hLF in C. reinhardtii is feasible and paved a way to commercial production of lactoferrin using edible Chlamydomonas expression system.

Abbreviations: atrazine chlorohydrolase gene (atzA); bovine serum albumin (BSA); human LF (hLF); lactoferrin (LF); Luria-Bertani (LB); quantitative reverse transcriptase PCR (qRT-PCR) ; SDS polyacrylamide gel electrophoresis (SDS-PAGE); Tris-acetate phosphate (TAP); western blotting (WB)