Isolation and phylogenetic identification of halotolerant/halophilic bacteria from the salt mines of Karak, Pakistan

Extreme environments like salt mines are inhabited by a variety of bacteria that are well-adapted to such environments. The bacterial populations provide economic benefits in terms of enzymes synthesis. The salt mines of Karak region in Pakistan are extremely saline and the microbial communities found here have not yet been explored. In the present study, 57 halotolerant/halophilic bacterial strains were isolated from the salt mines of Karak. These strains were grown in media with 0-35% NaCl concentration. The morphological and physiological characteristics of the isolated strains were studied to optimize the growth conditions and to classify the isolated bacterial strains into slightly halotolerant/halophilic, moderately halophilic and extreme halophilic. The phylogenetic analyses inferred from 16S rRNA gene sequence of the isolated strains demonstrated that the major population were closely related to species belonging to Planococcus, Jeotgalicoccus, Staphylococcus, Halobacillus, Halomonas, Brevibacterium, Gracilibacillus, Kocuria, Salinivibrio, Salinicoccus, Oceanobacillus and Bacillus genera. Results showed that the salt mines of Karak region are rich in halotolerant/halophilic bacterial population with diverse bacterial communities, which may be utilized in various industrial applications after proper screening and identification.

Consumer knowledge and attitudes to salt intake and labelled salt information

The objective of this study was to investigate consumers’ knowledge of health risks of high salt intake and frequency of use and understanding of labelled salt information. We conducted a cross-sectional survey in shopping centres within Metropolitan Melbourne. A sample of 493 subjects was recruited. The questionnaire assessed salt related shopping behaviours, attitudes to salt intake and health and their ability to interpret labelled sodium information. Four hundred and seventy four valid surveys were collected (65% female, 64% being the main shopper). Most participants knew of the relationship between salt intake and high blood pressure (88%). Sixty five percent of participants were unable to correctly identify the relationship between salt and sodium. Sixty nine percent reported reading the salt content of food products when shopping. Salt label usage was significantly related to shoppers concern about the amount of salt in their diet and the belief that their health could improve by lowering salt intake. Approximately half of the sample was unable to accurately use labelled sodium information to pick low salt options. Raising consumer awareness of the health risks associated with high salt consumption may increase salt label usage and purchases of low salt foods. However, for food labels to be effective in helping consumers select low salt foods a more ‘user friendly’ labelling format is needed.

An examination of the mediating role of salt knowledge and beliefs on the relationship between socio-demographic factors and discretionary salt use: a cross-sectional study

Background Discretionary salt use varies according to socio-demographic factors. However, it is unknown whether salt knowledge and beliefs mediate this relationship. This study examined the direct and indirect effect of socio-demographic factors on salt knowledge and discretionary salt use in a sample of 530 Australian adults.

Methods An internet based cross-sectional survey was used to collect data for this study. Participants completed an online questionnaire which assessed their salt knowledge, beliefs and salt use behaviour. Mplus was used to conduct structural equation modelling to estimate direct and indirect effects.

Results The mean age of the participants was 49.2 years, and about a third had tertiary education. Discretionary salt use was inversely related to age (r=-0.11; p<0.05), and declarative salt knowledge (knowledge of factual information) scores (r = -0.17; p<0.01), but was positively correlated with misconceptions about salt (r = 0.09; p<0.05) and beliefs about the taste of salt (r = 0.51; p<0.001). Structural equation modelling showed age, education and gender were indirectly associated with the use of discretionary salt through three mediating pathways; declarative salt knowledge, misconceptions about salt and salt taste beliefs.

Conclusions Inequalities observed between socio-demographic groups in their use of discretionary salt use can potentially be reduced through targeted salt knowledge and awareness campaigns.

Effects of high salt concentration and residue on copper and aluminum corrosion

Traditional researches on metal corrosion under salt solutions deposit conditions are usually carried out by visual, electron microscopic observations and simple electrochemical measurement via a traditional one-piece electrode. These techniques have difficulties in measuring localized corrosion that frequently occur in inhomogeneous media. This paper reports the results from the experiments using specially shaped coupons and a relatively new method of measuring heterogeneous electrochemical processes, namely, the wire beam electrode(WBE). Preliminary results from copper and aluminum corrosion in highly concentrated sodium chloride solutions with and without solid deposits show that the method is useful in simulating and studying corrosion especially localized corrosion in pipelines.

Dietary salt intake and discretionary salt use in two general population samples in Australia: 2011 and 2014

The limited Australian measures to reduce population sodium intake through national initiatives targeting sodium in the food supply have not been evaluated. The aim was, thus, to assess if there has been a change in salt intake and discretionary salt use between 2011 and 2014 in the state of Victoria, Australia. Adults drawn from a population sample provided 24 h urine collections and reported discretionary salt use in 2011 and 2014. The final sample included 307 subjects who participated in both surveys, 291 who participated in 2011 only, and 135 subjects who participated in 2014 only. Analysis included adjustment for age, gender, metropolitan area, weekend collection and participation in both surveys, where appropriate. In 2011, 598 participants: 53% female, age 57.1(12.0)(SD) years and in 2014, 442 participants: 53% female, age 61.2(10.7) years provided valid urine collections, with no difference in the mean urinary salt excretion between 2011: 7.9 (7.6, 8.2) (95% CI) g/salt/day and 2014: 7.8 (7.5, 8.1) g/salt/day (p = 0.589), and no difference in discretionary salt use: 35% (2011) and 36% (2014) reported adding salt sometimes or often/always at the table (p = 0.76). Those that sometimes or often/always added salt at the table and when cooking had 0.7 (0.7, 0.8) g/salt/day (p = 0.0016) higher salt excretion. There is no indication over this 3-year period that national salt reduction initiatives targeting the food supply have resulted in a population reduction in salt intake. More concerted efforts are required to reduce the salt content of manufactured foods, together with a consumer education campaign targeting the use of discretionary salt.

The state of legislation and policy protecting Australia's mangrove and salt marsh and their ecosystem services

Saline coastal wetlands, such as mangrove and coastal salt marsh, provide many ecosystem services. In Australia, large areas have been lost since European colonization, particularly as a result of drainage, infilling and flood-mitigation works, often starting in the mid-19th century and aimed primarily towards converting land to agricultural, urban or industrial uses. These threats remain ongoing, and will be exacerbated by rapid population growth and climate change in the 21st century. Establishing the effect of wetland loss on the delivery of ecosystem services is confounded by the absence of a nationally consistent approach to mapping wetlands and defining the boundaries of different types of coastal wetland. In addition, climate change and its projected effect on mangrove and salt marsh distribution and ecosystem services is poorly, if at all, acknowledged in existing legislation and policy. Intensifying climate change means that there is little time to be complacent; indeed, there is an urgent need for proper valuation of ecosystem services and explicit recognition of ecosystem services within policy and legislation. Seven actions are identified that could improve protection of coastal wetlands and the ecosystem services they provide, including benchmarking and improving coastal wetland extent and health, reducing complexity and inconsistency in governance arrangements, and facilitating wetland adaptation and ecosystem service delivery using a range of relevant mechanisms. Actions that build upon the momentum to mitigate climate change by sequestering carbon – ‘blue carbon’ – could achieve multiple desirable objectives, including climate-change mitigation and adaptation, floodplain rehabilitation and habitat protection.

Metamorphosis of a gold town : Stawell 1900-1940 : a study in local history

Examines the experience of the Wimmera town of Stawell as being representative of the early settlements created by gold rushes, and then threatened with extinction as the industry declined. Attention is paid to the role of community in Stawell's struggle to survive in the period between Federation and the Second World War. Reviews the economic and social processes involved in the eventual recovery. Argues that the forces of Stawell's historical legacy can be detected in the town's reaction to adversity after the closure of the last major mine in 1920.

Highly concentrated salt solutions : molecular dynamics simulations of structure and transport

Molecular dynamics (MD) simulations in NaI solutions, where the solvent has been represented by the Stockmayer fluid, were performed as a function of temperature, salt concentration, and solvent dipole strength. At higher temperatures contact ion pairs become more prevalent, regardless of solvent strength. An examination of the temperature dependence of the potential of mean force demonstrates the entropic nature of this effect. The transport properties calculated in the simulations are dependent on the balance between solvent dielectric constant and ion charge. In systems with a large solvent dipole moment, the ions appear to be independently mobile, and deviations from Nernst–Einstein behavior are small. In systems of smaller solvent dipole moment or greater ion charge, the ions form clusters, and large deviations from Nernst–Einstein behavior are observed.

The use of table and cooking salt in a sample of Australian adults

Dietary sodium, the major source being salt, is associated with hypertension. Australian adults consume more than the recommended amount of salt and approximately 15% of dietary sodium comes from salt added at the table and during cooking. Objective: To determine the frequency of and the demographic characteristics associated with discretionary salt use. Design: A cross sectional survey conducted in shopping centres within Metropolitan Melbourne. Participants completed a questionnaire assessing discretionary salt use and attitudes to salt intake. Outcomes: Four hundred and seventy four surveys were collected (65% female, 77% Caucasian, 64% holding a university qualification). Eighty nine percent of respondents were classified as salt users and 11% as non-salt users. Of the salt users 52% reported that they always or sometimes add salt during cooking and at the table. Those of Asian descent and younger respondents aged 18-24 years were more likely to be salt users (chi2=12.3, df=2, p<0.001; chi2=19.2, df=5, p<0.01). Conclusion: Discretionary salt use remains high. To successfully reduce population dietary salt intake public health campaigns are urgently required and need to include consumer advice to reduce discretionary salt use, whilst reducing the salt added to processed foods. Such campaigns should include younger age groups and should be appropriate for all ethnic backgrounds to raise the awareness of the risks of a high salt diet on health.

Health labelling can influence taste perception and use of table salt for reduced-sodium products

Objective : To investigate the effect of front-of-pack labels on taste perception and use of table salt for currently available and sodium-reduced soups.

Design : Within-subject design.

Setting : Sensory laboratory.

Subjects : Participants (n 50, mean age 34·8 (sd 13·6) years) were randomly served nine soups (250 ml each) across 3 d. Servings differed in: (i) health label (i.e. no health label, reduced-salt label or Heart Foundation Tick); and (ii) sodium reduction (no reduction – benchmark, 15 % less sodium or 30 % less sodium). Before tasting, participants rated their expected salt intensity and liking. After tasting, participants rated their perceived salt intensity and liking, after which they could add salt to the soup to make it more palatable.

Results : Reduced-salt labels generated a negative taste expectation and actual taste experience in terms of liking (P < 0·05) and perceived saltiness (P < 0·05). Perceived saltiness of sodium-reduced soups decreased more (P < 0·05), and consumers added more salt (P < 0·05), when soups carried the reduced-salt label. The tick logo and soups without health labels had no such influence on taste perception.

Conclusions : Emphasizing salt reduction by means of a front-of-pack label can have a negative effect on taste perception and salt use, especially when consumers are able to taste differences between their regular soup and the sodium-reduced soup. Overall health logos which do not emphasize the reduction in salt are less likely to affect perceived salt intensity and therefore are viable solutions to indicate the healthiness of sodium-reduced products.