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Motivations bias our responses to stimuli, producing behavioural outcomes that match our needs and goals. Here we describe a mechanism behind this phenomenon: adjusting the time over which stimulus-derived information is permitted to accumulate towards a decision. As a Drosophila copulation progresses, the male becomes less likely to continue mating through challenges 1-3 . We show that a set of copulation decision neurons (CDNs) flexibly integrates information about competing drives to mediate this decision. Early in mating, dopamine signalling restricts CDN integration time by potentiating Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) activation in response to stimulatory inputs, imposing a high threshold for changing behaviours. Later into mating, the timescale over which the CDNs integrate termination-promoting information expands, increasing the likelihood of switching behaviours. We suggest scalable windows of temporal integration at dedicated circuit nodes as a key but underappreciated variable in state-based decision-making., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Motivations bias our responses to stimuli, producing behavioral outcomes that match our needs and goals. We describe a mechanism behind this phenomenon: adjusting the time over which stimulus-derived information is permitted to accumulate toward a decision. As a Drosophila copulation progresses, the male becomes less likely to continue mating through challenges. We show that a set of Copulation Decision Neurons (CDNs) flexibly integrates information about competing drives to mediate this decision. Early in mating, dopamine signaling restricts CDN integration time by potentiating CaMKII activation in response to stimulatory inputs, imposing a high threshold for changing behaviors. Later into mating, the timescale over which the CDNs integrate termination-promoting information expands, increasing the likelihood of switching behaviors. We suggest scalable windows of temporal integration at dedicated circuit nodes as a key but underappreciated variable in state-based decision-making.

The aim of this work consists of developing a technological process for elaborating a virgin olive oil enriched in lutein-zeaxanthin extracted from spinach, studying different parameters like temperature, time of extraction and different ratios (spinach-oil). It was observed that the amount of carotenoids extracted increased up to a maximum after 24 hours and decreased as the maceration time progressed up to 60 hours, resulting of biological degradation. It was also observed that as more spinach we added, as more lutein-zeaxanthin in the enriched virgin olive oil was obtained. The best results were obtained after 24 hours by using a 75:25 ratio at 30°C. Values of oxidative stability decreased drastically, as well as other parameters such as acidity; peroxides index and Ks were modified when the enriched virgin olive oil was subjected to 45°C for 24 hours of maceration. Thus, the present procedure constitutes a way to achieve an increase in the daily intake of beneficial compounds.

Virgin Olive Oil (VOO) is a product much demanded by consumers looking for the highest quality and certain traits considered to be typical of the Mediterranean area. The olive fruit's properties and the industry-regulated physicochemical and sensory parameters of seven cultivars were evaluated during the ripening process. In general, the oil percentage in both the wet and dry material increased for all the cultivars from the green to the spotted stages of maturation, and they stayed constant statistically until the ripe stage with just a few exceptions. The lowest oil content was observed in the Manzanilla Cacereña cultivar in all stages of maturation. The cultivars that presented the lowest oil yields in the Abencor system were Manzanilla Cacereña and Carrasqueña, and the highest Corniche. In general, all the cultivars except one presented good behaviour during the mixing process, the exception being Manzanilla Cacereña which presented the lowest values of the extractability percentage. The moisture content of the olives presented a common pattern, increasing from the green to the spotted stage, with the differences being significant in the Corniche, Picual, and Verdial de Badajoz cultivars. All the oils analysed were classified into the "extra virgin" category according to the results for the regulated parameters. The fruity, bitter, and pungent attributes decreased during ripening in all the cultivars studied. In the green stage of maturation, Arbequina had the least intensity of bitterness and pungency, but there were no significant differences among cultivars in the fruity attribute.

The characterisation of virgin olive oil from Arbequina, Carrasqueña, Corniche, Manzanilla Cacereña, Morisca, Picual, and Verdial de Badajoz varieties according to the individual phenolic compounds at different ripening stage was carried out. In all olive oil varieties studied, secoiridoid derivatives were most abundant, followed by phenolic alcohols, flavonoids and phenolic acids. The secoiridoid derivatives of hydroxytyrosol were the most important complex phenols for Picual and Carrasqueña, whereas the tyrosol derivatives were the major ones found in Manzanilla Cacereña, and Verdial de Badajoz. For secoiridoid derivatives of hydroxytyrosol and tyrosol, Arbequina was the oil variety showing the lowest concentration. Tyrosol, hydroxytyrosol, vanillic acid, p-cumaric acid, luteolin, and apigenin levels were greater in early harvested samples in almost all oils analysed. Antioxidant activity measurements (antiradical, lipid peroxide inhibition, H2O2 and NO scavenging) were also accomplished for the seven varieties in the first ripening stage., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

This article reports about the presence of some of the components of minor fraction of virgin olive oils, polyphenols and tocopherols, in several of the VOO varieties from Extremadura. The relationship between both classes of compounds and the oxidative stability of the oils is also examined. The levels of total phenols, α, β, and γ tocopherols showed significant differences (p<0.05) among the different varieties. The concentration of total phenolic compounds varied from 130 to 1203 mg/kg. The α-tocopherol was the most representative in the seven varieties (95.97 %) and ranged from (288 - 170) to (485 - 244) mg/kg in the Morisca and Carrasqueña varieties respectively. On the other hand, a positive high lineal correlation was observed between oxidative stability and studied along the maturity of the fruit and the total phenolic compounds (natural antioxidants) (r(2)>0.90; p<0.05), α-tocopherol (r(2)>0.85; p<0.05), β-tocopherol (r(2)>0.70; p<0.05) and total-tocopherols (r(2)>0.87; p<0.05), in all the olive oils obtained from the seven varieties of olive from Extremadura. It is noticeable that α-tocopherol fraction contributed equally to the oxidative stability of all the VOO whereas the largest contribution was provided by the oil phenolic fraction, as it was the case of the Carrasqueña variety.

The aim of this research was to evaluate strategies for the development of a virgin olive oil (VOO) enriched with aqueous extracts of olive leaf and cake to increase the necessary dose in the diet of phenolic compounds with a natural product, as phenolic compounds are involved on the healthy properties of olive oil. Different extraction procedures were evaluated with the aim of increasing the phenol content and antioxidant potential of extracts of olive leaf and cake. As leaves extract presented a higher total phenolic content, it was characterized in order to determine its phenolic profile, and was employed to enrich VOO. Diverse procedures were used to prepare enriched VOO with the leaves extract, and finally the effects of phenol enrichment were evaluated based on the antioxidant potential and oxidative stability of the prepared phenol-enriched virgin olive oils. These enriched VOOs increased significantly the content in phenolic compounds, antioxidant potential and oxidative stability 40, 4 and 1.5 fold more, respectively, than the Control oil. Furthermore, the addition of lecithin had a positive effect both on the phenolic compounds content, and on the antioxidant potential of the oils. Besides, the use of the olive leaves extract, with and without lecithin respectively, supposes a strategy potential for reducing the harmful effects that inflicts long-term preservation of VOOs and its possible deterioration.

An actinomycete strain, isolated from a soil sample under a sugar cane plantation in Brazil and identified as Streptomyces viridobrunneus SCPE-09, was selected as a promising cellulolytic strain, and tested for its ability to produce cellulases from agro-industrial residues. Sugar cane bagasse or wheat bran was tested as carbon source, and corn steep liquor tested as nitrogen source. Different concentrations of carbon and nitrogen were tested using factorial design to identify optimal cellulose production. The results showed that media containing wheat bran 2.0% (w/v) and corn steep liquid 0.19% (w/v) lead to the highest production, 2.0 U mL(-1) of CMCase, obtained on the fifth day of fermentation. The pH and temperature profile showed optimal activity at pH 4.9 and 50°C. As for thermostability, endoglucanases were most tolerant at 50°C, retaining more than 80% of maximal activity even after 2 h of incubation. Zymogram analyses using supernatant from growth under optimized conditions revealed the presence of two CMCase bands with apparent molecular masses of 37 and 119 kDa. The combination of pH tolerance and CMCase production from agro-industrial residues by S. viridobrunneus SCPE-09 offers promise for future bioethanol biotechnologies.