Consumption of lactic acid bacteria (LAB) has been suggested to confer a range of health benefits including stimulation of the immune system and increased resistance to malignancy and infectious illness. In the present study, the effects of feeding Lactobacillus rhamnosus (HN001, DR20 TM ), Lactobacillus acidophilus (HN017) and Bifidobacterium lactis (HN019, DR10 TM ) on in vivo and in vitro indices of natural and acquired immunity in healthy mice were examined. Mice were fed daily with L. rhamnosus, L. acidophilus or B. lactis (10 9 colony forming units) and their immune function was assessed on day 10 or day 28. Supplementation with L. rhamnosus, L. acidophilus or B. lactis resulted in a significant increase in the phagocytic activity of peripheral blood leucocytes and peritoneal macrophages compared with the control mice. The proliferative responses of spleen cells to concanavalin A (a T-cell mitogen) and lipopolysaccharide (a B-cell mitogen) were also significantly enhanced in mice given different LAB. Spleen cells from mice given L. rhamnosus, L. acidophilus or B. lactis also produced significantly higher amounts of interferon-g in response to stimulation with concanavalin A than cells from the control mice. LAB feeding had no significant effect on interleukin-4 production by spleen cells or on the percentages of CD4 + , CD8 + and CD40 + cells in the blood. The serum antibody responses to orally and systemically administered antigens were also significantly enhanced by supplementation with L. rhamnosus, L. acidophilus or B. lactis. Together, these results suggest that supplementation of the diet with L. rhamnosus (HN001), L. acidophilus (HN017) or B. lactis (HN019) is able to enhance several indices of natural and acquired immunity in healthy mice.

B. lactis HN019 could be an effective probiotic dietary supplement for enhancing some aspects of cellular immunity in the elderly.

Fertilisers are one of the most important elements of modern agriculture. The application of fertilisers in agricultural practices has markedly increased the production of food, feed, fuel, fibre and other plant products. However, a significant portion of nutrients applied in the field is not taken up by plants and is lost through leaching, volatilisation, nitrification, or other means. Such a loss increases the cost of fertiliser and severely pollutes the environment. To alleviate these problems, enhanced efficiency fertilisers (EEFs) are produced and used in the form of controlled release fertilisers and nitrification/urease inhibitors. The application of biopolymers for coating in EEFs, tailoring the release pattern of nutrients to closely match the growth requirement of plants and development of realistic models to predict the release pattern of common nutrients have been the foci of fertiliser research. In this context, this paper intends to review relevant aspects of new developments in fertiliser production and use, agronomic, economic and environmental drives for enhanced efficiency fertilisers and their formulation process and the nutrient release behaviour. Application of biopolymers and complex coacervation technique for nutrient encapsulation is also explored as a promising technology to produce EEFs.

The importance of colostrum for the growth and health of newborn offspring is well known. In bovine colostrum, the antibody (immunoglobulin) complement system provides a major antimicrobial effect against a wide range of microbes and confers passive immunity until the calf's own immune system has matured. Bovine serum and lacteal secretions contain three major classes of immunoglobulins: IgG, IgM and IgA. The immunoglobulins are selectively transported from the serum into the mammary gland, as a result of which the first colostrum contains very high concentrations of immunoglobulins (40–200 mg/ml). IgG1 accounts for over 75 % of the immunoglobulins in colostral whey, followed by IgM, IgA and IgG2. All these immunoglobulins decrease within a few days to a total immunoglobulin concentration of 0.7–1.0 mg/ml, with IgG1 representing the major Ig class in milk throughout the lactation period. Together with the antibodies absorbed from colostrum after birth, the complement system plays a crucial role in the passive immunisation of the newborn calf. The occurrence of haemolytic or bactericidal complement activity in bovine colostrum and milk has been demonstrated in several studies. This review deals with the characteristics of bovine Igs and the complement system to be exploited as potential ingredients for health-promoting functional foods.

Oligosaccharides and glycoconjugates are some of the most important bioactive components in milk. A great deal of information is available on the biological function of the components from human milk. Their primary role seems to be in providing protection against pathogens by acting as competitive inhibitors for the binding sites on the epithelial surfaces of the intestine. Evidence is also available to support the role of some of these components as growth promoters for genera of beneficial microflora in the colon. Compared with human milk, levels of oligosaccharides in bovine milk are very low. Nevertheless, a number of neutral and acidic oligosaccharides have been isolated from bovine milk and characterised. The highest concentration of these molecules is found in early postparturition milk (colostrum). The chemical structure of the oligosaccharides and many of the glycoconjugates from bovine milk are similar to those in human milk. It is likely that bovine oligosaccharides and glycoconjugates can be used in milk products as bioactive components in human nutrition.

The application of probiotics and prebiotics to the manipulation of the microbial ecology of the human colon has recently seen many scientific advances. The sequencing of probiotic genomes is providing a wealth of new information on the biology of these microorganisms. In addition, we are learning more about the interactions of probiotics with human cells and with pathogenic bacteria. An alternative means of modulating the colonic microbial community is by the use of prebiotic oligosaccharides. Increasing knowledge of the metabolism of prebiotics by probiotics is allowing us to consider specifically targeting such dietary intervention tools at specific population groups and specific disease states.

Probiotics are defined as live microorganisms which when administered in adequate amounts confer a health benefit on the host.

In industrialized countries the incidence of diseases caused by immune dysregulation has risen. Epidemiologic studies initially suggested this was connected to a reduction in the incidence of infectious diseases; however, an association with defects in immunoregulation is now being recognized. Effector T(H)1 and T(H)2 cells are controlled by specialized subsets of regulatory T cells. Some pathogens can induce regulatory cells to evade immune elimination, but regulatory pathways are homeostatic and mainly triggered by harmless microorganisms. Helminths, saprophytic mycobacteria, bifidobacteria and lactobacilli, which induce immunoregulatory mechanisms in the host, ameliorate aberrant immune responses in the setting of allergy and inflammatory bowel disease. These organisms cause little, if any, harm, and have been part of human microecology for millennia; however, they are now less frequent or even absent in the human environment of westernized societies. Deficient exposure to these 'old friends' might explain the increase in immunodysregulatory disorders. The use of probiotics, prebiotics, helminths or microbe-derived immunoregulatory vaccines might, therefore, become a valuable approach to disease prevention.