Impact of milk protein type on the viability and storage stability of microencapsulated Lactobacillus acidophilus using spray drying

Three different milk proteins — skim milk powder (SMP), sodium caseinate (SC) and whey protein concentrate (WPC) — were tested for their ability to stabilize microencapsulated L. acidophilus produced using spray drying. Maltodextrin (MD) was used as the primary wall material in all samples, milk protein as the secondary wall material (7:3 MD/milk protein ratio) and the simple sugars, d-glucose and trehalose were used as tertiary wall materials (8:2:2 MD/protein/sugar ratio) combinations of all wall materials were tested for their ability to enhance the microbial and techno-functional stability of microencapsulated powders. Of the optional secondary wall materials, WPC improved L. acidophilus viability, up to 70 % during drying; SMP enhanced stability by up to 59 % and SC up to 6 %. Lactose and whey protein content enhanced thermoprotection; this is possibly due to their ability to depress the glass transition and melting temperatures and to release antioxidants. The resultant L. acidophilus powders were stored for 90 days at 4 °C, 25 °C and 35 °C and the loss of viability calculated. The highest survival rates were obtained at 4 °C, inactivation rates for storage were dependent on the carrier wall material and the SMP/d-glucose powders had the lowest inactivation rates (0.013 day−1) whilst the highest was observed for the control containing only MD (0.041 day−1) and the SC-based system (0.030 day−1). Further increase in storage temperature (25 °C and 35 °C) was accompanied by increase of the inactivation rates of L. acidophilus that followed Arrhenius kinetics. In general, SMP-based formulations exhibited the highest temperature dependency whilst WPC the lowest. d-Glucose addition improved the storage stability of the probiotic powders although it was accompanied by an increase of the residual moisture, water activity and hygroscopicity, and a reduction of the glass transition temperature in the tested systems

Breast cancer management pathways during the COVID-19 pandemic: outcomes from the UK 'Alert Level 4' phase of the B-MaP-C study

BACKGROUND: The B-MaP-C study aimed to determine alterations to breast cancer (BC) management during the peak transmission period of the UK COVID-19 pandemic and the potential impact of these treatment decisions. METHODS: This was a national cohort study of patients with early BC undergoing multidisciplinary team (MDT)-guided treatment recommendations during the pandemic, designated 'standard' or 'COVID-altered', in the preoperative, operative and post-operative setting. FINDINGS: Of 3776 patients (from 64 UK units) in the study, 2246 (59%) had 'COVID-altered' management. 'Bridging' endocrine therapy was used (n = 951) where theatre capacity was reduced. There was increasing access to COVID-19 low-risk theatres during the study period (59%). In line with national guidance, immediate breast reconstruction was avoided (n = 299). Where adjuvant chemotherapy was omitted (n = 81), the median benefit was only 3% (IQR 2-9%) using 'NHS Predict'. There was the rapid adoption of new evidence-based hypofractionated radiotherapy (n = 781, from 46 units). Only 14 patients (1%) tested positive for SARS-CoV-2 during their treatment journey. CONCLUSIONS: The majority of 'COVID-altered' management decisions were largely in line with pre-COVID evidence-based guidelines, implying that breast cancer survival outcomes are unlikely to be negatively impacted by the pandemic. However, in this study, the potential impact of delays to BC presentation or diagnosis remains unknown

Win-Win for Wind and Wildlife: A Vision to Facilitate Sustainable Development

Wind energy offers the potential to reduce carbon emissions while increasing energy independence and bolstering economic development. However, wind energy has a larger land footprint per Gigawatt (GW) than most other forms of energy production, making appropriate siting and mitigation particularly important. Species that require large unfragmented habitats and those known to avoid vertical structures are particularly at risk from wind development. Developing energy on disturbed lands rather than placing new developments within large and intact habitats would reduce cumulative impacts to wildlife. The U.S. Department of Energy estimates that it will take 241 GW of terrestrial based wind development on approximately 5 million hectares to reach 20% electricity production for the U.S. by 2030. We estimate there are ∼7,700 GW of potential wind energy available across the U.S., with ∼3,500 GW on disturbed lands. In addition, a disturbance-focused development strategy would avert the development of ∼2.3 million hectares of undisturbed lands while generating the same amount of energy as development based solely on maximizing wind potential. Wind subsidies targeted at favoring low-impact developments and creating avoidance and mitigation requirements that raise the costs for projects impacting sensitive lands could improve public value for both wind energy and biodiversity conservation

Soluble CD36 Ectodomain Binds Negatively Charged Diacylglycerol Ligands and Acts as a Co-Receptor for TLR2

BACKGROUND:Cluster of differentiation 36 (CD36) is a transmembrane glycoprotein involved in many biological processes, such as platelet biology, angiogenesis and in the aetiopathology of atherosclerosis and cardiovascular diseases. Toll-like receptors (TLRs) are one of the most important receptors of the innate immune system. Their main function is the recognition of conserved structure of microorganisms. This recognition triggers signaling pathways that activate transcription of cytokines and co-stimulatory molecules which participate in the generation of an immune response against microbes. In particular, TLR2 has been shown to recognize a broad range of ligands. Recently, we showed that CD36 serves as a co-receptor for TLR2 and enhances recognition of specific diacylglycerides derived from bacteria. METHODOLOGY/ PRINCIPAL FINDINGS:Here, we investigate the mechanism by which CD36 contributes to ligand recognition and activation of TLR2 signaling pathway. We show that the ectodomain of murine CD36 (mCD36ED) directly interacts with negatively charged diacylglycerol ligands, which explains the specificity and selectivity of CD36 as a TLR2 co-receptor. We also show that mCD36ED amplifies the pro-inflammatory response to lipoteichoic acid in macrophages of wild-type mice and restores the pro-inflammatory response of macrophages from mice deficient in CD36 (oblivious), but not from mice deficient in cluster of differentiation 14 (CD14) (heedless). CONCLUSION/ SIGNIFICANCE: These data indicate that the CD36 ectodomain is the only relevant domain for activation of TLR2 signaling pathway and that CD36 and CD14 have a non-redundant role for loading ligands onto TLR2 in the plasma-membrane. The pro-inflammatory role of soluble CD36 can be relevant in the activation of the immune response against pathogens, as well as in the progression of chronic diseases. Therefore, an increased level of soluble forms of CD36, which has been reported to be increased in type II diabetic patients, could accelerate atherosclerosis by increasing the pro-inflammatory response to diacylglycerol ligands

Ingredient Supplementation Effects on Viability of Probiotic Bacteria in Yogurt

The present investigation studied the effects of cysteine, whey powder, whey protein concentrate, acid casein hydrolysates, or tryptone on the viability of Streptococcus thermophilus, Lactobacillus acidophilus, and bifidobacteria. Changes in pH, titratable acidity, redox potential, and viability of bacteria were monitored during 24 h of fermentation and refrigerated storage (4°C) of yogurt for 35 d. The incubation time that was needed to reach pH 4.5 was considerably affected by the added ingredients. Also, the drop in pH or the increase in acidity and redox potential was dependent on the added ingredients. The addition of cysteine, whey protein concentrate, acid casein hydrolysates, or tryptone improved the viability of bifidobacteria to a variable extent, but whey powder failed to improve their viability. The morphology of S. thermophilus, as shown by electron microscopy, was affected by cysteine at 500 mg/L, possibly as a result of reduced redox potential. Sodium dodecyl sulfate-PAGE and amino acid analyses suggested that the nitrogen source in the form of peptides and amino acids improved the viability of bifidobacteria in yogurt made with a commercial ABT (Lactobacillus acidophilus, bifidobacteria, and Streptococcus thermophilus) starter culture, which showed a dramatic decline in the counts of this organism in previous studies.link_to_subscribed_fulltex

Antimicrobial substance produced by Lactobacillus helveticus 2700

Fifteen lactic acid bacteria (LAB) were screened for their ability to produce antimicrobial substances against Lactobacillus delbrueckii ssp. bulgaricus 2519, Lactobacillus helveticus 2700, Lactobacillus casei 2603 and Lactobacillus jugurti 2819. Of the fifteen LAB, L. helveticus 2700, Lactobacillus plantarum 2903 and Lactobacillus fermentum 5174 exhibited antimicrobial activity. The characteristics of the antimicrobial substance produced by L. helveticus 2700 were studied. The antimicrobial substance produced in fermented milk by L. helveticus 2700 inhibited seven strains of L. delbrueckii ssp. bulgaricus, the producer organism L. helveticus 2700, 14 strains of L acidophilus and one strain each of L. plantarum 2903 and L. jugurti 2819, but not the other LAB, spoilage and pathogenic micro-organisms tested. The antimicrobial activity of L. helveticus 2700 was not due to organic acids or hydrogen peroxide. The molecular weight of the substance was less than 5000 daltons. The substance was active over a pH range of 3.0-10.0, and inactivation occurred at 70°C.link_to_subscribed_fulltex

Evaluation of Media for Selective Enumeration of Streptococcus thermophilus, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus acidophilus, and Bifidobacteria

Fifteen media were evaluated to determine their suitability for selective enumeration of Streptococcus thermophilus, Lactobacillus delbrueckii ssp. bulgaricus, Lactobacillus acidophilus, and bifidobacteria using 5 to 6 strains of each of the four groups of organisms. Streptococcus thermophilus agar was found to be suitable for selective enumeration of S. thermophilus under aerobic incubation at 37°C for 24 h. The MRS agar at pH 5.2 or reinforced clostridial agar at pH 5.3 could be used for the selective enumeration of L. delbrueckii ssp. bulgaricus when the incubation was carried out at 45°C for ≥72 h. However, the recovery of this organism was lower on MRS agar at pH 5.2 or reinforced clostridial agar at pH 5.3 than that obtained on MRS agar. The recovery of L. acidophilus and bifidobacteria on MRS agar and MRS-maltose agar was similar; MRS-maltose agar could be used to enumerate total counts of L. acidophilus and bifidobacteria. For selective enumeration of L. acidophilus, MRS-salicin agar or MRS-sorbitol agar could be used. For selective enumeration of bifidobacteria, MRS NNLP (nalidixic acid, neomycin sulfate, lithium chloride, and paromomycin sulfate) agar was suitable; however, determination of bifidobacteria by differential counts between L. acidophilus enumerated on MRS-salicin agar or MRS-sorbitol agar and the total counts of L. acidophilus and bifidobacteria obtained from MRS-maltose agar resulted in higher recovery of some strains of bifidobacteria. Other media that were evaluated in this study were not suitable for selective enumeration.link_to_subscribed_fulltex

The influence of ingredient supplementation on the textural characteristics of yogurt

This investigation studied the effects of cysteine, whey powder (WP), whey protein concentrates (WPC1 and WPC2), acid casein hydrolysate (ACH) and tryptone on the textural properties of yogurts. Yogurt supplemented with 2% WPC1 was the firmest among all yogurt samples and its firmness was significantly higher (p<0.001) than other yogurts. The firmness of the control yogurt was similar to that supplemented with ACH, tryptone or cysteine at 50 and 250 mg/L level, but the firmness was significantly higher (p<0.001) with WPC1 and significantly lower (p<0.001) in yogurt made with WP and a high level of cysteine (500 mg/L). The viscosity of yogurt made with various ingredients showed significant differences (p<0.001) and an average increase in viscosity of ∼1.2 to 1.6 times was observed during refrigerated storage of 30 days, except for that supplemented with WPC2. The microscopic texture analyses of yogurt showed that the protein network of yogurt varied with various ingredients. Increased concentration of cysteine resulted in an irregular network of protein in the finished product and also affected the firmness and viscosity of the yogurt. The flocs and pores were large in the product supplemented with WPC. By contrast, an even and more regular protein network with very small flocs and pores was observed in the control yogurt and that supplemented with ACH or tryptone.link_to_subscribed_fulltex