Publications by authors named "Daniel Pereira Silva"

Biosurfactants are amphiphilic biomolecules with promising tensoative and emulsifying properties that find application in the most varied industrial sectors: environment, food, agriculture, petroleum, cosmetics, and hygiene. In the current work, a 2 full-factorial design was performed to evaluate the effect and interactions of pineapple peel and corncob as substrates for biosurfactant production by Bacillus subtilis LMA-ICF-PC 001. In a previous stage, an alkaline pretreatment was applied to corncob samples to extract the xylose-rich hydrolysate.

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Biosurfactants are eco-friendly compounds with unique properties and promising potential as sustainable alternatives to chemical surfactants. The current review explores the multifaceted nature of biosurfactant production and applications, highlighting key fermentative parameters and microorganisms able to convert carbon-containing sources into biosurfactants. A spotlight is given on biosurfactants' obstacles in the global market, focusing on production costs and the challenges of large-scale synthesis.

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Background: Cervical cancer is a major concern to women's health, being the fourth most common cancer worldwide. A great percentage of these cancer is consequence of an HPV infection, namely from specific genotypes such as 16/18. Portuguese screening program subjects women to a reflex cytology triage every 5 years.

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The use of non-conventional carbon sources for biosurfactant-producing microorganisms is a promising alternative in fermentation to substitute costly substrates. So, the current research used pineapple peel as a cost-effective and renewable substrate because of its rich composition in minerals and sugars and high availability. Following a 2 full factorial design, a bacterial strain of Bacillus subtilis produced biosurfactants in fermentative media containing different concentrations of glucose and concentrated pineapple peel juice (CPPJ).

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Article Synopsis
  • * Research utilized a central composite design to analyze how various substrates, including glucose and pineapple peel, impact surface tension reduction and emulsification index.
  • * The results showed that pineapple peels can effectively replace some glucose and mineral salts, leading to a high surface tension reduction rate (57.744%) and maximum emulsification index (61.92%) under specific conditions.
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The reuse of agro-industrial waste has been a recurring issue since the 20th century. With a composition rich in carbohydrates and because of the massive amount of residue produced daily all over the world, corncob became a low-cost and suitable substrate to produce high added-value compounds. Biosurfactants are bioproducts of versatile applications due to their chemical structure with hydrophilic and hydrophobic regions.

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The biosurfactant production is characterized by high costs with substrates, which does not make them sufficiently competitive against synthetic surfactants. The insertion of alternative sources of low cost, especially agro-industrial residue, is an excellent alternative to make this competitiveness viable. An alkaline pretreatment was used to extract the hemicellulose from corncob in order to enhance its C5 fraction, common to vegetable biomasses.

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Background: Although the risk of human papillomavirus (HPV) infection is greatest in young women, women older than 25 years remain at risk. We present data from the VIVIANE study of the HPV 16/18 AS04-adjuvanted vaccine in adult women after 7 years of follow-up.

Methods: In this phase 3, double-blind, randomised controlled trial, healthy women older than 25 years were enrolled (age stratified: 26-35 years, 36-45 years, and ≥46 years).

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A novel strategy for the production of lipase by Bacillus sp. ITP-001 in a stirred tank fermenter using perfluorodecalin (PFD) was studied. Firstly, a response surface methodology 2(2) with three central points was employed to optimise the effect of agitation speed and aeration rate in lipase production.

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The aim of this work was to evaluate the activity of bromelain in pineapple plants (Ananas comosus var. Comosus), Pérola cultivar, produced in vitro in different culture conditions. This enzyme, besides its pharmacological effects, is also employed in food industries, such as breweries and meat processing.

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Background: Extensive information on cervical cancer is currently available. Its effectiveness in reducing anxiety in women receiving abnormal Pap tests is not clear. We investigated current practices of communicating abnormal Pap results to evaluate women's reactions and determine the sources of information they use subsequently.

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Hexokinase (HK) and glucose 6-phosphate dehydrogenase (G6PDH) are important enzymes used in biochemical studies and in analytical methods. The stability of the enzymes can be affected by several variables, pH being one of them. The effect of pH on the stability of HK and G6PDH was evaluated in this work.

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In a 5-L fermentor (NBS-MF 105), Saccharomyces cerevisiae (0.7 g/L) was inoculated into a liquid medium (pH 4.0) containing 17 g/L of glucose, 2.

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Synopsis of recent research by authors named "Daniel Pereira Silva"

  • - Daniel Pereira Silva's research primarily focuses on the production and application of biosurfactants derived from agro-industrial waste, particularly utilizing substrates like pineapple peel and corncob to develop cost-effective fermentation processes.
  • - Silva's findings highlight the potential of these organic waste materials as renewable resources, demonstrating their effectiveness in enhancing the growth of biosurfactant-producing microorganisms and addressing environmental waste management issues.
  • - Additionally, Silva has contributed to the field of public health with studies on HPV's screening programs in Portugal, focusing on the cost-effectiveness of different screening methods and the continued risks associated with HPV in older women.