Antibacterial activity of different essential oils obtained from spices widely used in Mediterranean diet

Raw and processed foods are open to contamination during their production, sale and distribution. At present, therefore, a wide variety of chemical preservatives are used throughout the food industry to prevent the growth of food spoiling bacteria. However health and economic considerations have led to a search for alternatives, such as essentials oils that can safely be used as substitutes for fungicides and bactericides to partially or completely inhibit the growth of fungi and bacteria. The aim of this work was to determine the effectiveness of the essentials oils from oregano (Origanum vulgare), thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), sage (Salvia officinalis), cumin (Cuminum cyminum) and clove (Syzygium aromaticum) on the growth of some bacteria commonly used in the food industry, Lactobacillus curvatus, Lactobacillus sakei, Staphylococcus carnosus and Staphylococcus xylosus or related to food spoilage Enterobacter gergoviae, Enterobacter amnigenus. The agar disc diffusion method was used to determine the antibacterial activities of the oils. All six essential oils analysed had an inhibitory effect on the six tested bacteria. Oregano essential oil showed the highest inhibition effect followed by cumin and clove.     

Between the City Lights and the Shade of Exclusion: Post-War Accelerated Urban Transformation of Luanda,Angola

With nearly five centuries of history and major war-related impacts in the second half of the twentieth century, Luanda has recently been subject to outstanding changes that make the capital of Angola an important urban case study for Africa. Today, the city is not only an evident materialization of the oil wealth being channelled into reconstruction after decades of civil war but also reflects and translates the diverse perspectives of its residents and policy makers regarding the city and urban life. As it is reconfigured, it also transforms the mentalities and daily lives of urban dwellers and policy stakeholders, reinforcing the idea of improvement and modernity. In order to better understand the processes of physical and social change that have taken place within the city and the intertwined logics, this article makes reference to three distinct key stages of its history, pointing out their main features and the transformations that have occurred: the colonial period of sociospatial dualization (1576–1974), the period between independence and the last peace agreement (1975–2002) of profound and extensive urban mixture and the post-war period (2002–present) marked by accelerated sociospatial reconfigurations. More specifically, it analyses the very recent urban phenomena, the urban plans and new urban features, discussing the correlations between physical transformations and the rationalities and perspectives that accompany them, both of the urban planners and of the urban dwellers, discussing the implications in terms of new inclusions and exclusions in the city.     

Natural fermentation of lentils. Functional properties and potential in breadmaking of fermented lentil flour

The effects of fermentation on functional properties of lentil flour and rheological properties of doughs and breads produced from blends of wheat and fermented lentil flour were studied. Lentil protein solubility was higher at neutral pH than acid pH; the lowest and highest protein solubility values were observed at pH 4.0 and pH 7.0, respectively. Water hydration capacity and fat binding capacity of fermented lentil flour (FLF) were always higher than those of non-fermented lentil flour (NFLF), irrespective of fermentation temperature (28–42°C) and flour concentration (79–221 g/l). Emulsifying properties of NFLF were similar to the properties of other legume flours in the range used in experiment. In contrast, the emulsion capacity and stability of FLF were very low and flours fermented at 42°C did not even form emulsion. Rheological properties of doughs made from wheat-fermented lentil blends were similar to those from wheat flour with the addition of other legume flours such as pea and bean. Good quality breads were produced at 2.5 to 10% NFLF and FLF supplementation (except for bread with 10% FLF addition which was middle quality).     

Response surface optimisation of germination conditions to improve the accumulation of bioactive compounds and the antioxidant activity in quinoa

Germination has been proposed as an economic approach to improve the content of bioactive compounds in pseudocereals. In this work, response surface methodology (RSM) was employed to investigate the impact of germination conditions on the phytochemical content and antioxidant activity of quinoa. The use of desirability methodology showed that the optimum conditions to maximise the content of total phenolic content (TPC) and antioxidant activity in sprouted quinoa were 20 °C for 42 h. Sprouts produced under these conditions exhibited increases of 80% and 30% in TPC and antioxidant activity, respectively, compared to un‐germinated seeds, and contained high γ‐aminobutyric acid (GABA) concentration. The nonsignificant lack‐of‐fit and high determination coefficients obtained confirmed the suitability of the predictive models developed for TPC and antioxidant activity, whilst the one obtained for GABA was not significant (R² < 0.75) within the conditions studied. Sprouting under optimum conditions enhanced the content of both flavonoid and nonflavonoid compounds, being the increase in flavonoids more pronounced. Kaempferol‐O‐dirhamnosyl‐galactopyranose and quercetin‐O‐glucuronide were the compounds that experienced the most noticeable increase in quinoa after germination. In conclusion, this study provides useful information on the optimum germination conditions to improve the levels of health‐promoting compounds in quinoa.     

Formulation,Characterization and Stability Assessment of a Food‐Derived Tripeptide,Leucine‐Lysine‐Proline Loaded Chitosan Nanoparticles

The chicken‐ or fish‐derived tripeptide, leucine‐lysine‐proline (LKP), inhibits the angiotensin converting enzyme and may be used as an alternative treatment for prehypertension. However, it has low permeation across the small intestine. The formulation of LKP into a nanoparticle (NP) has the potential to address this issue. LKP‐loaded NPs were produced using an ionotropic gelation technique, using chitosan (CL113). Following optimization of unloaded NPs, a mixture amount design was constructed using variable concentration of CL113 and tripolyphosphate at a fixed LKP concentration. Resultant particle sizes ranged from 120 to 271 nm, zeta potential values from 29 to 37 mV, and polydispersity values from 0.3 to 0.6. A ratio of 6:1 (CL113:TPP) produced the best encapsulation of approximately 65%. Accelerated studies of the loaded NPs indicated stability under normal storage conditions (room temperature). Cytotoxicity assessment showed no significant loss of cell viability and in vitro release studies indicated an initial burst followed by a slower and sustained release.     

Smart sensors/actuators for biomedical applications: Review

This paper reflects on review of smart sensor activities for biomedical applications. The rise of biotechnology has provided innovative development of new therapies and detection methods for life threatening diseases. As a worldwide research focus, there is especially a strong interest in the use of microsystems in health care, particularly as smart implantable devices. Recent years have seen an increasing activity of hip and knee replacement and other type of implants, which are some of the most frequently performed surgical procedures in the world. Loosening of hip prosthesis is the dominant issue for many patients who undergo a hip arthroplasty. Artificial joints are subject to chronic infections associated with bacterial biofilms, which only can be eradicated by the traumatic removal of the implant followed by sustained intravenous antibiotic therapy. This review focuses on the clinical experience using all kinds of smart implants like orthopedic implants instrumented with strain gauges, retina implant system using image sensors. Technical design improvements will enhance function, quality of life, and longevity of total knee arthroplasty and all other kind of implants. Application of biocompatible nanomaterials in implantable biosensors for continuous monitoring of metabolites is an area of sustained scientific and technological interests.     

Se improves indole glucosinolate hydrolysis products content, Se-methylselenocysteine content, antioxidant capacity and potential anti-inflammatory properties of sauerkraut

Selenium (Se) has a well-known role in prevention of chronic diseases associated with oxidative stress and inflammation. The objective was to produce Se-enriched sauerkraut and to study the effect of selenite addition on indole glucosinolate hydrolysis products, vitamin C, Se biotransformation and microbial quality. The antioxidant activity of sauerkraut and its ability to inhibit NO production in LPS-induced macrophages were also examined. White cabbage was naturally fermented with 0.3 mg of Na₂SeO₃/kg fresh cabbage (NFSe) or without Se addition (NF). Total Se content reached up to 1.29 μg/g d.m. (0.11 μg/g f.m.). Selenomethylselenocysteine was the major Se form found in NFSe cabbage. Se addition caused a slight reduction of ascorbigen (6%) and vitamin C (5%) contents in sauerkraut (P ? 0.05); however, lactic acid bacteria increased (3%), and the formations of indole-3-carbinol and indole-3-acetonitrile were markedly enhanced (74% and 13%, respectively). NFSe cabbage extracts showed higher (P ? 0.05) antioxidant activity (163 μmol trolox/g d.m.) and inhibition of NO production in LPS-induced macrophages (IC₅₀ = 44.0 μg/ml) than did NF cabbage extracts. Consequently, Se-enriched sauerkraut can be considered as a health-promoting food.