A landscape review of controlled release urea products: Patent objective, formulation and technology.

Fertiliser has been a vital part of agriculture due to it boosting crop productivity and preventing starvation throughout the world. Despite this huge contribution, the application of nitrogen (N) fertilisers results in N leaching and the formation of greenhouse gases, which threaten the environment and human health. To minimise the impacts, slow/controlled release fertilisers (S/CRFs) have been being developed since the beginning of the 20th century. Despite the efforts made over a century, the basic terminological and classification information of these fertilisers remains vague. The scientific knowledge published in S/CRF patents has also been overlooked since the beginning. This review focused on the information gaps, clarified the definitions, differentiation and classification methods that have been randomly used in previous literature. The objectives, formulations and technologies of 109 controlled release urea patents involving sulphur coated urea, polymer coated urea and urea matrix fertilisers published in the years since these products emerged were also reviewed to 1) highlight the overlooked scientific knowledge in the patents; 2) understand the evolutionary processes and current research states of the products; 3) clarify research preferences and challenges to date; 4) identify remaining gaps for the future direction. It is expected that the organised basic information and the patent knowledge highlighted in this paper can be new resources and foster the development of S/CRFs in the future.

Viability assessment of Bifidobacterium longum ATCC 15707 on non-dairy foods using quantitative fluorescence microscopy.

This study demonstrates an effective technique for separating and purifying viable bacteria from samples that interfere with viability staining. The viability of Bifidobacterium longum ATCC 15707 was assessed using Percoll Buoyant Density Gradient Centrifugation (PBDC) to separate bacteria from complex non-dairy food matrices and Quantitative Fluorescence Microscopy (QFM) to determine individual cells using LIVE/DEAD BacLight bacterial viability staining. Water agar (3%) was used to retain cells of B. longum and offered a lower fluorescence background with BacLight viability staining, compared with fixation on polycarbonate (PC) black membrane. The effect of drying temperatures and non-dairy foods on viability of B. longum was assessed. B. longum coated on oat, peanut or raisin was separated by filtration, low- and high-speed centrifugation, flotation and sedimentation buoyant density centrifugation. Purified cells were subsequently deposited on water agar for rehydration followed by LIVE/DEAD BacLight viability staining and enumeration. Conventional plate counting was also conducted to compare viability results. Finally, this method was applied to assess cell membrane damages of B. longum incorporated onto non-dairy foods during 24 h drying. Furthermore, viability assessment of B. longum coated onto oat, peanut, or raisin was much lower by plate counting compared to viability staining. Drying appeared to have a greater impact when viability was assessed by plate counting compared to viability staining. IMPORTANCE: Enumeration of viable beneficial bacteria from function foods presents a significant bottleneck for product development and quality control. Interference with microscopic and/or fluorescent techniques by ingredients, time required to incubate plated microbes, and the transient nature of the colony forming unit make rapid assessment of viable bacteria difficult. Viability assessment of Bifidobacterium longum ATCC 15707 by Percoll Buoyant Density Gradient Centrifugation with LIVE/DEAD BacLight viability staining on water agar (3%) was in agreement with serial dilution enumeration. Without the need for incubation viability assessment by staining provided a more rapid means to assess the impact of drying on the viability of B. longum coated onto oat, peanut or raisin.

Effect of Non-Dairy Food Matrices on the Survival of Probiotic Bacteria during Storage.

The viability of probiotics in non-dairy food products during storage is required to meet content criteria for probiotic products. This study investigated whether non-dairy foods could be matrices for probiotics. Selected probiotic bacteria were coated on non-dairy foods under two storage conditions, and viabilities were assessed. The non-dairy foods were coated with 5-7 log cfu g-1 of Lactobacillus acidophilus ATCC4356T, Lactobacillus plantarum RC30, and Bifidobacterium longum ATCC15707T. The coated non-dairy foods were stored at 20 °C and 20% relative humidity (RH) or 30 °C and 50% RH. Viability of probiotic bacteria was determined after 0, 2, and 4 weeks of storage. B. longum showed the highest survival at week 4 of 6.5-6.7 log cfu g-1 on wheat bran and oat, compared with 3.7-3.9 log cfu g-1 of L. acidophilus and 4.2-4.8 log cfu g-1 of L. plantarum at 20 °C 20% RH. Under the storage conditions of 30 °C 50% RH, survival of 4.5 log cfu g-1 of B. longum was also found on oat and peanut. This was two and four times higher than the population of L. acidophilus and L. plantarum, respectively. The results suggest that probiotics can survive on non-dairy foods under ambient storage conditions. However, the storage conditions, food matrices, and probiotic strains should be carefully chosen to maximize probiotic bacteria survival.

Mimicking filtration and transport of rotavirus and adenovirus in sand media using DNA-labeled, protein-coated silica nanoparticles.

Rotavirus (RoV) and adenovirus (AdV) are important viral pathogens for the risk analysis of drinking water. Despite this, little is known about their retention and transport behaviors in porous media due to a lack of representative surrogates. We developed RoV and AdV surrogates by covalently coupling 70-nm sized silica nanoparticles with specific proteins and a DNA marker for sensitive detection. Filtration experiments using beach sand columns demonstrated the similarity of the surrogates' concentrations, filtration efficiencies and attachment kinetics to those of the target viruses. The surrogates showed the same magnitude of concentration reduction as the viruses. Conversely, MS2 phage (a traditional virus model) over-predicted concentrations of AdV and RoV by 1- and 2-orders of magnitude respectively. The surrogates remained stable in size, surface charge and DNA concentration for at least one year. They can be easily and rapidly detected down to a single particle. Preliminary tests suggest that they were readily detectable in a number of environmental waters and treated effluent. With up-scaling validation in pilot trials, the surrogates developed here could be a cost-effective new tool for studying virus retention and transport in porous media. Examples include assessing filter efficacy in water and wastewater treatment, tracking virus migration in groundwater after effluent land disposal, and establishing safe setback distances for groundwater protection.

Dichelobacter nodosus, Fusobacterium necrophorum and the epidemiology of footrot.

Footrot is a debilitating disease of sheep resulting in lameness, production losses and suffering. To study the basic bacteriology of the disease, a survey was initiated across commercial farms and non-commercial research flocks to compare the bacteriology of symptomatic footrot infected sheep with healthy asymptomatic sheep. Of the 80 farmers initially contacted, 14 collected hoof swabs and returned the swabs by post. Following DNA extraction, species-specific PCR was used to identify if Dichelobacter nodosus (D. nodosus) or Fusobacterium necrophorum (F. necrophorum) species were present on each swab. Of the 42 swabs taken from symptomatic footrot infected sheep, 17 were positive for both F. necrophorum and D. nodosus, two were positive for F. necrophorum only, two for D. nodosus only and 23 swabs were negative for both F. necrophorum and D. nod osus. Of the 50 swabs received from healthy asymptomatic sheep, one was positive for F. necrophorum only and 49 were negative for both D. nodosus and F. necrophorum. This suggests that both F. necrophorum and D. nodosus are linked to footrot in the field in a pastoral farming system. If these bacteria are linked together and collectively cause footrot, this may need to be considered when managing a footrot outbreak, or maintaining a quarantine.

Variation in Fusobacterium necrophorum strains present on the hooves of footrot infected sheep, goats and cattle.

Footrot is a disease of sheep, goats and cattle that causes losses in production and raises welfare issues world-wide. The disease is characterised by destruction of the hard keratin of the hoof leading to lameness, and both Dichelobacter nodosus (D. nodosus) and Fusobacterium necrophorum (F. necrophorum) are thought to be involved in the etiology of this disease. While a lot is known about the genetic diversity of D. nodosus, very little is known about variation in F. necrophorum, especially as regards its role in footrot. We used PCR in conjunction with SSCP and sequencing to analyse swabs collected from the hooves of sheep, goats and cattle with symptomatic footrot for the presence of a portion of the lktA gene of F. necrophorum. Out of 29 samples tested, 27 had amplifiable lktA sequences and within these we found four different variants of the lktA gene. Eight of the nine samples from cattle were positive for a variant that matched the type strain of F. necrophorum subsp. necrophorum. Of the 14 samples from sheep, 13 were positive for lktA, but none of theses matched the known type strains, and 11/13 of the lktA sequences were identical. This sequence was distinct to those of the type strains. None of the footrot infections carried multiple variants of lktA, suggesting that only one strain of F. necrophorum is present in each case. This is in contrast to D. nodosus in footrot infections, which have been demonstrated to have up to seven strains infecting a single hoof.

Protein transduction of dendritic cells for NY-ESO-1-based immunotherapy of myeloma.

Myeloma vaccines, based on dendritic cells pulsed with idiotype or tumor lysate, have been met with limited success, probably in part due to insufficient cross-priming of myeloma antigens. A powerful method to introduce myeloma-associated antigens into the cytosol of dendritic cells is protein transduction, a process by which proteins fused with a protein transduction domain (PTD) freely traverse membrane barriers. NY-ESO-1, an immunogenic antigen by itself highly expressed in 60% of high-risk myeloma patients, was purified to near homogeneity both alone and as a recombinant fusion protein with a PTD, derived from HIV-Tat. Efficient entry of PTD-NY-ESO-1 into dendritic cells, confirmed by microscopy, Western blotting, and intracellular flow cytometry, was achieved without affecting dendritic cell phenotype. Experiments with amiloride, which inhibits endocytosis, and N-acetyl-l-leucinyl-l-norleucinal, a proteasome inhibitor, confirmed that PTD-NY-ESO-1 entered dendritic cells by protein transduction and was degraded by the proteasome. Tetramer analysis indicated superior generation of HLA-A2.1, CD8+ T lymphocytes specific for NY-ESO-1(157-165) with PTD-NY-ESO-1 compared with NY-ESO-1 control protein (44% versus 2%, respectively). NY-ESO-1-specific T lymphocytes generated with PTD-NY-ESO-1 secreted IFN-gamma indicative of a Tc1-type cytokine response. Thus, PTD-NY-ESO-1 accesses the cytoplasm by protein transduction, is processed by the proteasome, and NY-ESO-1 peptides presented by HLA class I elicit NY-ESO-1-specific T lymphocytes.