Multifactorial analysis of unstable non-acid milk occurrence in dairy production/ Análise multifatorial da ocorrência de leite instável não ácido em propriedades leiteiras

The aim was to analyze the Unstable Non-Acid Milk (UNAM) phenomenon through the association of zootechnical characteristics of the farms relating them to their occurrence. The data collection was carried out in 12 dairy farms which received a technical visit to learn the production system: handling, feeding, mineralization and milking procedures. The milk samples were analyzed for fat, protein, lactose, solids not fat, standard plate count, somatic cell count, pH, titratable acidity and ethanol test stability. Milk data were submitted to analysis of variance; association between zootechnical characteristics and UNAM were determined by logistic regression; and multivariate analysis of principal components was carried out. The occurrence of UNAM was verified in 25% of the evaluated farms. In UNAM herds 27% to 33% of the cows were classified as UNAM. The animals with UNAM milk was different between farms classified as Stable or UNAM, being 12% and 30% of cows, respectively. The detection of UNAM was possible when in the herd there are at least 23% of the animals producing UNAM milk. The three principal components identified covered the main areas of influence on the occurrence of UNAM: Quality and interaction with part of the solids; Production and relationship with lactose; Nutrition and correlations with part of the components. The classification of milk in the expansion tank as UNAM can only be identified when more than 23% of the animals were in this condition. The multivariate analysis identified that the nutritional balance of each cow was determining factor for UNAM presence.

Effect of dietary mannan oligosaccharides and fructo-oligosaccharides on physico-chemical indices, antioxidant and oxidative stability of broiler chicken meat

The objective of this present study was to investigate the potentiality of prebiotics (mannan oligosaccharides-MOS and fructo-oligosaccharides-FOS) in replacement of antibiotic growth promoter and their relationship with physico-chemical indices, antioxidant and oxidative stability and carcass traits of broiler chickens meat. Accordingly, 240 day-old broiler chicks of uniform body weight divided in 6 treatment groups with 5 replicate each (5 × 6 = 30) having 8 birds in each replicate. Six corn based dietary treatments were formulated viz. T1 (control diet), T2 (T1 + Bacitracin methylene di-salicylate @ 0.002%), T3 (T1 + 0.1% MOS), T4 (T1 + 0.2% MOS), T5 (T1 + 0.1% FOS), and T6 (T1 + 0.2% FOS). Significant (p < 0.05) increase in cut up part yields (%) and reduction in cholesterol and fat content in T4 (0.2% MOS) group. The water holding capacity (WHC) and extract release volume (ERV) were increase (p < 0.05) in 0.1 or 0.2% MOS supplemented group. DPPH (1, 1-diphenyl-2-picrylhydrazy) was higher (p < 0.05) and lipid oxidation (free fatty acid and thio-barbituric acid reactive substances) was lower (p < 0.05) in T4 group. The standard plate count (SPC), staphylococcus and coliform counts were decreased (p < 0.05) in T3 or T4 group. Thus, it can be concluded that mannan oligosaccharides (MOS) may be incorporated at 0.2% level in diet for improved physico-chemical indices, antioxidant and oxidative stability and carcass characteristics of broiler chickens meat and it may be suitable replacer of antibiotic growth promoter.

VaxArray Immunoassay for the Multiplexed Quantification of Poliovirus D-Antigen

Next generation poliovirus vaccines are critical to reaching global poliovirus eradication goals. Recent efforts have focused on creating inactivated vaccines using attenuated Sabin strains that maintain patient safety benefits and immunogenicity of conventional inactivated vaccines while increasing manufacturing safety and lowering production costs, and on developing novel oral vaccines using modified Sabin strains that provide critical mucosal immunity but are further attenuated to minimize risk of reversion to neurovirulence. In addition, there is a push to improve the analytical tools for poliovirus vaccine characterization. Conventional and Sabin inactivated poliovirus vaccines typically rely on standard plate-based ELISA as in vitro D-antigen potency assays in combination with WHO international standards as calibrants. While widely utilized, the current D-antigen ELISA assays have a long time to result (up to 72 hours), can suffer from lab-to-lab inconsistency due to non-standardized protocols and reagents, and are inherently singleplex. For D-antigen quantitation, we have developed the VaxArray Polio Assay Kit, a multiplexed, microarray-based immunoassay that uses poliovirus-specific human monoclonal antibodies currently under consideration as standardized reagents for characterizing inactivated Sabin and Salk vaccines. The VaxArray assay can simultaneously quantify all 3 poliovirus serotypes with a time to result of less than 3 hours. Here we demonstrate that the assay has limits of quantification suitable for both bioprocess samples and final vaccines, excellent reproducibility and precision, and improved accuracy over an analogous plate-based ELISA. The assay is suitable for adjuvanted combination vaccines, as common vaccine additives and crude matrices do not interfere with quantification, and is intended as a high throughput, standardized quantitation tool to aid inactivated poliovirus vaccine manufacturers in streamlining vaccine development and manufacturing, aiding the global polio eradication effort.

Comparison of Probiotic Isolate Growth in Natural Culture with Various Carbon Sources

Probiotik merupakan mikroba hidup yang memberikan pengaruh menguntungkan pada inang karena dapat menyeimbangkan mikroba yang ada dalam saluran pencernaan menjadi meningkat. Pemanfaatan tersebut dapat memberikan pengaruh positif dan kesehatan bagi inang sehingga sangat baik untuk diaplikasikan. Pemanfaatan bahan alami dapat menekan biaya media tumbuh sehingga perlu penggantian media sintetik dengan media alami karena memiliki harga yang relatif lebih murah tetapi mengandung nutrien penting bagi pertumbuhan mikroba. Tujuan penelitian ini adalah untuk mengetahui pertumbuhan isolat probiotik berdasarkan lama waktu kutur dalam media alami yang mengandung sumber karbon berbeda. Pertumbuhan isolat probiotik dalam berbagai sumber karbon dilakukan melalui metode Standard Plate Count (SPC). Melalui metode SPC didapatkan jumlah koloni isolat G dari masing-masing media berupa kanji, sagu, dan dedak yaitu 2,3 x 108 Cfu/mL, 6,4 x 106 Cfu/mL, dan 4,3 x 106 Cfu/mL selama 48 jam; 2,6 x 108 Cfu/mL, 1,6 x 108 Cfu/mL, dan 1,0 x 108 Cfu/mL selama 96 jam; 4,6 x 108 Cfu/mL, 1,8 x 108 Cfu/mL, dan 1,2 x 108 Cfu/mL selama 144 jam. Hasil yang didapatkan menunjukkan bahwa isolat G mampu ditumbuhkan dalam media alami berupa kanji, sagu dan dedak.

Phage Endolysin LysP108 Showed Promising Antibacterial Potential Against Methicillin-resistant Staphylococcus aureus

As a potential antibacterial agent, endolysin can directly lyse Gram-positive bacteria from the outside and does not lead to drug resistance. Considering that XN108 is the first reported methicillin-resistant Staphylococcus aureus (MRSA) strain in mainland China with a vancomycin MIC that exceeds 8 µg mL-1, we conducted a systematic study on its phage-encoded endolysin LysP108. Standard plate counting method revealed that LysP108 could lyse S. aureus and Pseudomonas aeruginosa with damaged outer membrane, resulting in a significant reduction in the number of live bacteria. Scanning electron microscopy results showed that S. aureus cells could be lysed directly from the outside by LysP108. Live/dead bacteria staining results indicated that LysP108 possessed strong bactericidal ability, with an anti-bacterial rate of approximately 90%. Crystal violet staining results implied that LysP108 could also inhibit and destroy bacterial biofilms. In vivo animal experiments suggested that the area of subcutaneous abscess of mice infected with MRSA was significantly reduced after the combined injection of LysP108 and vancomycin in comparison with monotherapy. The synergistic antibacterial effects of LysP108 and vancomycin were confirmed. Therefore, the present data strongly support the idea that endolysin LysP108 exhibits promising antibacterial potential to be used as a candidate for the treatment of infections caused by MRSA.

The Use of Ultrasound for Preventing Honey Crystallization

The aim of this study was to evaluate the effect of ultrasound treatment for preventing honey crystallization on the physicochemical and microbiological properties of unifloral honey and polyfloral honey. Honey samples without any treatment were used as a control group for comparison. The effect of applying ultrasound treatment was evaluated by studying over time the tendency of crystallization, the rheological properties of honey and chemical and microbiological properties. The parameters analyzed for the two groups of samples (treated and untreated with ultrasound), which did not vary or had small variations during the research were water content, acidity, water activity, glucose, fructose, sucrose, glucose/water ratio, glucose/fructose ratio. The crystallization process was installed in the control samples from the first month of the study, and much later in the treated samples. The color of the untreated samples varied considerably, and the color of the treated ones remained stable or slightly varied. For the control samples, the smallest variation in hydroxymethylfurfural (HMF) concentration was in raspberry honey (5%), and the most significant variation was in honeydew honey (30%). For the treated samples, the largest variation of this parameter was found in tillia honey (127%), and the smallest variation was in rapeseed honey (26%). The microbiological quality was higher for the treated samples. In the ultrasound-treated samples of acacia honey, honeydew honey and grassland honey, yeasts, molds or standard plate counts (SPCs) were undetectable. For control samples, SPC values were <10–50 cfu/g. Ultrasound-treated samples maintained their SPC parameter levels or were thus reduced (<10–20 cfu/g). Yeasts and molds were undetectable or had value between <10 and 10 cfu/g. The yeasts and the molds ranged in the control samples between <10 and 40 cfu/g.

Effect of channel and fin geometries on a trapeze plate-fin heat sink performance

This study aims to achieve a minimum base temperature (or junction temperature) and hence better thermal performance. Trapezoidal curved plate-fin heat sink with dolphin fins and rectangular channel (Model-1) and trapezoidal curved plate-fin heat sink with dolphin fins, cut corner, and rectangular channel (Model-2) were designed and compared with a standard plate-fin heat sink. The effects of fins on the airflow and heat transfer in designed plate-fin heat sinks have been investigated numerically. The numeric results show that the use of fins and small changes in geometry significantly improve the heat transfer rate. Outcomes of the study showed 44–51% and 57–62% convective heat transfer enhancement compared with a standard plate-fin heat sink, without any overall mass augmentation, in Model-1 and Model-2, respectively. The presence of dolphin fins reduces the thermal resistance by up to 30%, which contributes to the overall thermal enhancement of the designed plate-fin heat sinks. Simulation results show that increasing the fins in areas close to the heat source and reducing the non-working areas significantly influence the thermal performance of heat sinks. The results also show that the trapeze plate-fin heat sinks with the different channel-fin geometries are superior to the standard trapeze plate-fin heat sink in thermal performance.

Bacteriological quality of raw milk marketed in and around Guwahati city, Assam, India

Background and Aim: Milk is a highly perishable commodity, which is subjected to various types of contamination right from the farm level to the consumers' table. This study aimed to assess the quality of raw milk sold in and around Guwahati city based on the microbial load. Materials and Methods: A total of 200 raw pooled milk samples collected from 25 different locations in and around Guwahati city were subjected to quality evaluation based on the methylene blue reduction test (MBRT), standard plate count, and coliform count as per the standard procedure. Results: Out of the 200 samples evaluated, more than 50% of them were graded as poor to very poor quality based on the MBRT results. None of the samples could be graded as excellent quality and only 14.5% were graded as good quality. The standard plate count and coliform count of all the raw milk samples were found to be significantly higher than the legal standard. A highly significant (p<0.01) difference was observed for standard plate count and coliform count among the different locations in and around Guwahati city. Conclusion: From the present study, it could be inferred that raw milk sold in most parts of Guwahati city do not confer to the legal microbiological standard and may pose a high risk of milk-borne illness among consumers of the city, which needs a systematic series of actions to be implemented properly.

Bacteria Screening with Sufficient Nitrate Extraction from Wastewater

Search for effective biological strain for use to remedy water pollution has been limited. This study was performed to search for effective bacteria capable of extracting nitrate from wastewater. Samples from abattoir inside (Abi) and abattoir outside (Abt), fishpond of kwalkwalawa (Fpk) and mabera fishpond (Fpm) wastewater were used. Using conventional standard plate technique as 1.96×107 cfu/ml (Abi) had highest bacteria count while 1.05×107 cfu/ml (Fpk) had minimal. The obtained pure colonies were morphologically and biochemically characterized including two Enterobacter specie, Proteus and Pseudomonas specie. The isolated organisms were used as a test organism for the removal of nitrate present in high nitrate containing medium. Prior to the extraction, the wastewater samples were physicochemically analyzed using parameters like color, odor, pH, alkalinity, hardness, temperature and nitrate. For nitrate extraction, bacteria were inoculated in a separate tubes containing nitrate broth, incubated in a rotary shaker 150rpm at 37°C for 16hrs. The supernatant from 10minutes centrifuged culture were used for nitrate removal evaluation after a series of reaction and stop using spectrophotometer at 420nm. The absorbance 0.732 proteus specie after estimation of nitrate in a medium was maximal while Enterobacter specie 0.574 was minimal. Meanwhile, two of the Enterobacter specie has similar absorbance 0.012 while Proteus and Pseudomonas species had 0.016 and 0.010 respectively in the nitrate concentration removed within the media. The nitrate present in the medium was compared with a known standard curve prepared with NaNO3 at 100-1000 ppm. The result indicated that bacteria from fish pond wastewaters had highest potential for extracting nitrate and that inherent bacteria are capable of removing pollutant nitrate and the bacteria may be able to remove nitrate efficiently if genetically engineered.