Emerging applications of nanotechnologies to probiotics and prebiotics

Fervid interests on nanoparticles are increasing within the scientific and non-scientific communities, as they are utilised in food and non-food applications. The versatility of emerging applications of nanoparticles makes them potentially harmful to the food, healthcare and environment sectors, and thus necessitates the development of nanonutraceuticals from nutritional substances such as antioxidants, vitamins, fatty acids, fibres, probiotics and prebiotics. This review excavated state of the art on nanotechnology applications such as gold and selenium particles, nanolayers, nanobeads, nanoemulsions and nanofibers to probiotics and prebiotics for the synthesis of anticancer, antimicrobial, antioxidant and photo-reactive products among others, and finally delved into other noteworthy considerations like safety. It is concluded that available literature on the current status of nanoprobiotics and prebiotics are exhaustive, despite their huge potentials and applications.     

Serum Amyloid A3 Promoter-Driven Luciferase Activity Enables Visualization of Diabetic Kidney Disease

The early detection of diabetic nephropathy (DN) in mice is necessary for the development of drugs and functional foods. The purpose of this study was to identify genes that are significantly upregulated in the early stage of DN progression and develop a novel model to non-invasively monitor disease progression within living animals using in vivo imaging technology. Streptozotocin (STZ) treatment has been widely used as a DN model; however, it also exhibits direct cytotoxicity to the kidneys. As it is important to distinguish between DN-related and STZ-induced nephropathy, in this study, we compared renal responses induced by the diabetic milieu with two types of STZ models: multiple low-dose STZ injections with a high-fat diet and two moderate-dose STZ injections to induce DN. We found 221 genes whose expression was significantly altered during DN development in both models and identified serum amyloid A3 (Saa3) as a candidate gene. Next, we applied the Saa3 promoter-driven luciferase reporter (Saa3-promoter luc mice) to these two STZ models and performed in vivo bioluminescent imaging to monitor the progression of renal pathology. In this study, to further exclude the possibility that the in vivo bioluminescence signal is related to renal cytotoxicity by STZ treatment, we injected insulin into Saa3-promoter luc mice and showed that insulin treatment could downregulate renal inflammatory responses with a decreased signal intensity of in vivo bioluminescence imaging. These results strongly suggest that Saa3 promoter activity is a potent non-invasive indicator that can be used to monitor DN progression and explore therapeutic agents and functional foods.     

The role of rheological behaviour in flavour perception in model oil/water emulsions

Decreasing the fat content of a food produces changes in a range of physical, chemical and sensory properties that are important in flavour perception. The aim of this paper was to study the role of rheological behaviour in flavour perception in model oil/water emulsions, using a series of samples with different hydroxypropyl methyl cellulose (HPMC) and oil content. The composition of the emulsions was adjusted to deliver iso-release aroma in vivo and to produce samples with the same viscosity in-mouth (measured as the Kokini oral shear stress). The results showed that there was no significant difference in perceived thickness between the three samples providing further evidence that the Kokini oral sheer stress is well correlated with in-mouth thickness. However, there was a significant difference in perceived volatile fruity flavour and sweetness. Samples containing the highest oil content were perceived as significantly less fruity and sweet despite having the same volatile release and in-mouth thickness.     

A review on selection of fermentative microorganisms for functional foods and beverages: the production and future perspectives

Fermentation has been employed as a traditional means of improving the shelf life and nutritional contents of foods, thus making fermented foods and beverages functional and therapeutic. Lactic acid bacteria (LAB) plays a major role in determining the health benefits of fermented milk and related products. This review takes into cognizance numerous investigations reporting certain microbial strains and mixes to contribute safety, quality, stability, health and organoleptic properties to fermented foods, due to increased consumers’ awareness of food products with health claims. A look was taken at selection criteria for the ideal fermentative microbial species and strains, their usefulness and prospective ‘OMICS‘-based approaches to elucidating fermentative complex communities in relation to their effects on fermented food products. Moreover, recommendations were given for improved fermentation of beverages and functional foods. It is projected that fermented foods and beverages will continually be a paramount in the global food and emerging functional food market.     

Corrosion Resistance Studies of Austenitic Stainless Steel Grades in Molten Zinc-Aluminum Alloy Galvanizing Bath

The corrosion inhibition performance and mechanical behavior of galvanized and heat-treated four newly developed austenitic stainless steel grades and type 316L austenitic stainless steel for application as sink rolls in galvanizing baths of 0.14–0.21 wt.% aluminum was investigated and compared through immersion corrosion test to determine the weight loss between 168 and 504 h, tensile test, and Charpy impact test. The delta ferrite content of the test samples was observed and estimated through optical microscopy, feritscope, and ONRL diagram. Scanning electron microscopy and energy dispersive spectroscopy were used to characterize the surface microstructure, morphology, and chemical composition of the galvanized coating of the steel samples. Result showed that only two of the newly developed stainless steel compositions were selected for use in fabrication of galvanizing hardware based on the comparisons of corrosion and mechanical performances of tested alloys.     

Applications of soy protein hydrolysates in the emerging functional foods: a review

Several applications of protein hydrolysates have been documented including gelation, solubility and emulsifying properties. However, very rare reviews have solely explored the potentials of soy protein hydrolysates (SPHs). Varying and abundant pieces of information on the physicochemical properties of soy proteins, such as foaming, solubility, emulsifying, gelling, fat- and water-holding capacities, suggest their hydrolysates to be equally or more important. In this regard, this review highlights the different methods that have been used to prepare SPHs, coupled with the most promising applications and potentials of SPHs. Nonetheless, further investigations are necessary to validate the potentialities of SPHs as food agents for the emerging functional foods.     

Human colonic microbiota modulation and branched chain fatty acids production affected by soy protein hydrolysate

Several functional properties have been attributed to soy protein hydrolysates (SPHs); however, their gut fermentation needs to be investigated. This study aimed to determine the effect of hypo-allergic pepsin-educed SPH on the growth of gut microbiota, SCFA and BCFA production in a pH-controlled, stirred, batch culture fermentation system compared with commercial SPH and soy protein isolate (SPI). The results showed that all substrates affected gut bacteria. SPH selectively increased the number of lactobacilli (log 9.61 to log 9.84) at 72-h fermentation, but not for bifidobacteria. This is in accordance with increased BCFAs yield of 15.54 ± 0.00 mm (isobutyrate) and 465.59 ± 1.42 mm (isovalerate). The gut microbial balance index (GMBI) of SPH was 0.23, thus suggesting its gut microbial modulation. Therefore, SPH has potential for modulation or balance of gut microbiota, which may be used as functional ingredient for emerging market of nutraceuticals and nutri-pharmaceutical industry.     

Hydrogen storage in destabilized borohydride materials

Several new destabilized borohydride systems were prepared by mechanochemical synthesis and characterized to determine their suitability for hydrogen storage. The mixtures included: Mg(BH₄)₂/Ca(BH₄)₂; Mg(BH₄)₂/CaH₂/3NaH; and Mg(BH₄)₂/CaH₂; systems as well as a double cation hydride MnLi(BH₄)₃. Temperature programmed desorption, TPD, analyses showed that the desorption temperature of Mg(BH₄)₂ can be lowered by ball milling it with Ca(BH₄)₂. The resulting mixture absorbed and released hydrogen with the pressure composition temperature, PCT, isotherm displaying a well-defined plateau region. The other two systems; Mg(BH₄)₂/CaH₂ and Mg(BH₄)₂/CaH₂/NaH, can also absorb and release hydrogen. The desorption enthalpies are all in the 84–88 kJ/mol range. These systems, however, are only partially reversible and lose some of their hydrogen-holding capacity after the initial desorption. A plausible explanation for this is that the mechanisms involve the formation of a (B₁₂H₁₂)⁻²-containing intermediate which has a high kinetic barrier to re-hydrogenation. TPD analysis also showed that the double cation material, MnLi(BH₄)₃ can release hydrogen in the range of 130 °C but the process is irreversible. A Kissinger analysis of the first decomposition step in the differential thermal analysis, DTA, data showed that the activation energies for all the Mg(BH₄)₂-based borohydrides range from 115 to 167 kJ/mol.