Newborn mammals are totally dependent on maternal milk and care for survival. The mother’s brain undergoes different behavioural, physiological and emotional adaptations that make the mother more ...likely to satisfy the demands of the offspring. Recent reports from our group show that, compared to nulliparous rats, lactation diminishes cell damage induced by excitotoxicity in the dorsal hippocampus of the dam after systemic or i.c. administration of kainic acid (KA) and the resulting motor seizures. Elevated levels of prolactin (PRL), oxytocin, progesterone and glucocorticoids are characteristics of lactation, and the pronounced fluctuation of these hormones occurring in this phase may play a role protecting the hippocampus. Indeed, PRL administration to ovariectomised rats significantly diminishes the deleterious effects of KA in the dorsal hippocampus and reduces the progression of KA‐induced seizures. Thus, lactation is a natural model for neuroprotection because it effectively prevents acute and chronic cell damage of the hippocampus induced by excitotoxicity.
Many parameters affect phage-bacteria interaction. Some of these parameters depend on the environment in which the bacteria are present. Anaerobiosis effect on phage infection in facultative ...anaerobic bacteria has not yet been studied. The absence of oxygen triggers metabolic changes in facultative bacteria and this affects phage infection and viral life cycle. Understanding how an anaerobic environment can alter the behavior of phages during infection is relevant for the phage therapy success.
Plants that express resistance to herbivores emit volatile organic compounds (VOCs) that can trigger resistance responses in undamaged neighbours. Recent reports indicate that VOCs can also trigger ...the resistance to pathogens, an effect that might be due to different mechanisms: the priming of an induced expression of resistance genes in the receiver or direct inhibitory effects on microbial pathogens that cause a passive ‘associational’ resistance in the VOC‐exposed plant. We investigated whether VOCs emitted from a resistant common bean (Phaseolus vulgaris) cultivar enhance the resistance to the fungus Colletotrichum lindemuthianum in a susceptible cultivar and analysed whether specific VOCs are likely to directly affect the pathogen. We found that susceptible plants exposed to the headspace of resistance‐expressing plants over 6 h became phenotypically as resistant as the resistant cultivar. Several resistance marker genes (PATHOGENESIS‐RELATED PR 1, 2 and 4) were primed in VOC‐exposed susceptible plants. After challenging, these genes reached expression levels at least as high as in the resistant cultivar. Additionally, individual VOCs such as limonene, linalool, nonanal, methyl salicylate and methyl jasmonate at natural concentrations directly inhibited the germination of conidia as did also the headspace of a resistance‐expressing plant. This inhibition of conidial germination was dosage‐dependent and irreversible. Synthesis. We conclude that VOCs are involved in the resistance of bean to fungal pathogens. They can contribute to the direct resistance in the emitter itself, and resistance phenotypes of neighbouring receiver plants can result from induced as well as associational resistance. Plant VOCs play multiple roles in the resistance of plants to microbial pathogens.
This study aimed to evaluate the influence of temperament and parity on milk production and metabolic responses of Holstein cows in a pasture-based automatic milking system. Thirty-five primiparous ...and 58 multiparous cows were classified as ‘calm’, ‘intermediate’ or ‘reactive’ in each of the temperament tests conducted: milking reactivity (MR), race time (RT), flight speed, and flight distance. The milk yield and milk composition, as well as the blood biochemistry, were measured during the first 10 weeks of lactation. Primiparous cows produced less milk than multiparous cows (24.0 ± 0.8 vs. 34.2 ± 0.6 L/d, respectively, P ˂ 0.0001), while the serum beta-hydroxybutyrate concentration differences according to parity were not detected. Multiparous cows that were classified as ‘reactive’ on MR and RT tests produced 3 kg/d more milk and had greater concentrations of milk components than ‘calm’ cows (P ≤ 0.05). There was no such relation in primiparous cows. Also, cows scored ‘reactive’ on RT showed greater milking frequency (2.50 ± 0.05 vs. 2.35 ± 0.04 milking/d; P = 0.01) and blood beta-hydroxybutyrate concentrations (1.28 ± 0.09 vs. 0.92 ± 0.10 mmol/L; P = 0.04) than RT ‘calm’ cows. In conclusion, the cows' temperament was associated with milk production and metabolism, which depended on parity and the temperament tests used. Although productive performance was different between parities, lipomobilization was not.
•Cows' productive and metabolic traits were assessed in an automatic milking system.•Temperament and parity influenced cows' production and metabolism at early lactation.•Primiparous had lower milking frequency, milk yield, fat, protein and lactose than multiparous.•Multiparous reactive cows had greater milking frequency, milk yield, fat, protein and lactose.•The temperament influences depend on parity and temperament tests used.
The main sensory defects found in virgin olive oil (winey–vinegary, mustiness–humidity, fusty and rancid) were studied by dynamic headspace high-resolution gas chromatography with flame ionisation ...and mass spectrometry detection and dynamic headspace high-resolution gas chromatography–olfactometry to determine the most prominent volatile compounds responsible for them. A comparative study between defective and high quality virgin olive oils showed qualitative and quantitative differences in the volatile profiles, explained by the presence of enzymatic activities before the oil extraction process or by alteration during olive oil storage. The highest sensory significance, evaluated by odour activity values, corresponded to 1-octen-3-ol for mustiness–humidity, ethyl butanoate, propanoic and butanoic acids for fusty sensory defect, acetic acid, 3-methyl butanol and ethyl acetate for winey–vinegary and several saturated and unsaturated aldehydes and acids for rancid sensory defect.
Virgin olive oil is inevitably subject to an oxidation process during storage that can affect its stability and quality due to off-flavors that develop before the oil surpasses its 'best before' ...date. Many parameters are involved in the oxidation process at moderate conditions. Therefore, a multiparametric study is necessary to establish a link between physico-chemical changes and sensory quality degradation in a real storage experiment. In this context, a storage experiment of 27 months was performed for four monovarietal virgin olive oils, bottled in transparent 500-mL PET bottles and subjected to conditions close to a supermarket scenario. Volatile composition, quality parameters and phenolic compounds were determined monthly. Simultaneously, an accredited sensory panel assessed their sensory characteristics. The stability of the fresh samples was also studied with the oxidative stability index (OSI) and mesh cell-FTIR. (
)-2-hexenal, (
)-3-hexen-1-ol and (
)-2-hexen-1-ol were identified as markers of the fruity attribute. Hexanal and nonanal were also identified as compounds that were associated with the rise of median of defect during storage. Some disagreements were observed between the sensory assessment and the OSI analyzed by Rancimat. However, the increase of concentration of rancid markers agreed with the increase of aldehyde band measured with mesh cell-FTIR.
•EVOOs were differentiated between green fruity and ripe fruity sensory classes.•Sensory and volatile analyses were developed and correlated.•Three analytical methods were assessed for volatile ...characterization of classes.•The advantages of PARADISe processing for volatile analyses were confirmed.•Some volatile compounds were identified as “green” or “ripe” fruity markers.
An objective sensory evaluation of extra virgin olive oil (EVOO), involving the chemical characterization of positive attributes, is of interest. These attributes are objectively divided, according to fruitiness, into “green” and “ripe” fruity. This work studied the differentiation in the volatile profile of EVOOs into these two classes, obtained by three analytical methods, including different extraction techniques and detectors and two data processing strategies, and their relation with sensory results. According to the results, each method allowed the characterization of the two classes, providing information on different volatile compounds, which increased in number through PARADISe software (14 more than the conventional processing). Moreover, some volatile compounds showed significant differences between the two classes, 16 highlighted by the variables with importance in projection (VIP) for green fruity (e.g. (Z)-3-hexen-1-ol, methyl ether) and 23 for ripe fruity EVOOs (e.g. (Z)-2-hexen-1-ol), which could be considered as useful markers to complement quality assessment.
Trade standards are continuously updated to give plausible solutions to situations created by fraudsters who apply the most sophisticated procedures to their objectives of olive oil adulteration. ...Clustered inside targeted and profiling approaches, methods based on spectroscopic, isotopic and chromatographic techniques are reviewed. Chromatographic methods, most of them being official methods, compete with newer methods based on spectroscopic, isotopic and trace element techniques for ensuring that the pace of research in the detection of malpractices is rapid enough.
The speed of the analyses, the need of statistical interpretation of the results, the quality parameters of the methods, limit of detection of the adulterants, and the applicability range among others are on the basis for the absolute and comparative analyses of the most known methods, which results are unpacked in the paper. The new frontiers of research in the field of olive oil authenticity are also dissected together with the challenges for the near future.
The extensive and deep analysis of the methods for quantifying the chemical compounds responsible for olive oil authenticity will contribute to a better comprehension of the complex analytical world of olive oil for the analyst working with this food product for the first time, as well as for experienced professionals.
•Critical analyses of standard methods with practical comments are provided.•Tools for olive oil analysis are divided into targeted and profiling methodologies.•Despite the high number of methods, there are still unsolved adulterations.•The geographical traceability is one of the new authenticity challenges.
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