Associated Laboratory for Green Chemistry - Clean Technologies and Processes

Funder

Organizational Unit

Publications

DNA screening of Drosophila suzukii predators in berry field orchards shows new predatory taxonomical groups

Publication . Sario, Sara; Santos, Conceição; Gonçalves, Maria de Fátima; Torres, L.

Drosophila suzukii (spotted wing drosophila, SWD) is a pandemic quarantine pest that attacks mostly red fruits. The high number of life cycles per year, its ability to rapidly invade and spread across new habitats, and highly polyphagous nature, makes this a particularly aggressive invasive species, for which efficient control methods are currently lacking. The use of native natural predators is particularly promising to anchor sustainable and efficient measures to control SWD. While several field studies have suggested the presence of potential predatory species in infested orchards, only a few confirmed the presence of SWD DNA in predators’ gut content. Here, we use a DNA-based approach to identify SWD predators among the arthropod diversity in South Europe, by examining the gut content of potential predator specimens collected in SWD-infested berry fields in North Portugal. These specimens were morphologically identified to the family/order, and their gut content was screened for the presence of SWD DNA using PCR. New SWD predatory taxonomical groups were identified, as Opiliones and Hemerobiidae, in addition to known SWD predators, such as Hemerobiidae, Chrysopidae, Miridae, Carabidae, Formicidae and Araneae. Additionally, the presence of a spider family, Uloboridae, in the orchards was recorded for the first time, posing this family as another SWD-candidate predator. This study sets important bases to further investigate the potential large-scale use of some of these confirmed predator taxa for SWD control in South Europe.

2021Journal article

Open access

Inhibition of pancreatic α-amylase activity by a group of hydroxyxanthones

Publication . Santos, Clementina M.M.; Proença, Carina; Freitas, Marisa; Araújo, Alberto N.; Silva, Artur; Fernandes, Eduarda

Diabetes mellitus is a non-infectious and non-transmissible life threatening disease. It is one of the fastest growing health challenges of the current century, in which the number of adults living with diabetes have more than tripled over the past 20 years. According to the International Diabetes Federation, 1 in 11 adults (20-79 years) have diabetes (463 million people) and 2 in 3 people with diabetes live in urban areas.1 This may be closely related to genetic and lifestyle factors such as physical inactivity, unhealthy diets, obesity, raised blood cholesterol and glucose, stress, etc.2 Diabetes mellitus is an endocrine disorder that occurs when pancreas does not produce enough insulin, when the body cannot use insulin efficiently or both situations, leading to chronic hyperglycemia. Thus, the control of postprandial blood glucose level via the inhibition of digestive enzymes, such as α-glucosidase and/or α-amylase, is a relevant strategy for the management of type 2 diabetes and its complications.3 During the last two decades, in the pursuit for novel antidiabetic drugs, a wide variety of natural and synthetic xanthone derivatives have been applied in the inhibition of α-glucosidase enzyme activity, however, the effects of this class of compounds on the activity of α-amylase enzyme is scarce.4 With this ratio in mind and as part of our on-going project, the aim of the present study is to investigate the effect of a series of hydroxyxanthones 1 on pancreatic α-amylase activity to find out the relevance of this group of compounds in controlling blood glucose levels for the treatment of disorders related with the carbohydrate uptake. Different concentrations of xanthones 1 were incubated with the enzyme and the hydrolysis of the substrate 2-chloro-p-nitrophenyl-α-D-maltotriose was monitored spectrophotometrically at 405 nm. Acarbose was used as the standard inhibitor. In addition, the study of the inhibition type was carried out through nonlinear regression Michaelis-Menton enzymatic kinetics and the corresponding Lineweaver-Burk plot.5 The results pointed out that the IC50 values obtained ranged from 23 to 90 μM, considerably higher than the values obtained for the positive control acarbose (IC50 = 0.62 ± 0.07 μM). For the active compounds, two of them revealed a competitive type of inhibition while for the remaining ones a noncompetitive type of inhibition was recorded. More details concerning the structureactivity relationship will be presented and discussed in this communication.

2020Conference object

Open access

Application of an electronic tongue as a single-run tool for olive oils’ total phenols and oxidative stability estimation

Publication . Marx, Ítala; Rodrigues, Nuno; Veloso, Ana C.A.; Casal, Susana; Pereira, J.A.; Peres, António M.

Olive oil quality can be enhanced during olive oil extraction, particularly by promoting the extraction of phenolic compounds extraction leading to the increase of the oxidative stability (OS). However, both total phenols content (TPC) and OS measurements (Folin-Ciocalteau spectrophotometric method and Rancimat, respectively) are time-consuming and expensive tasks, of difficult implementation in production lines. Thus, the present work studied the feasibility of using a potentiometric lab-made electronic tongue (E-tongue, Figure 1A), comprising non-specific lipid polymeric sensor membranes, coupled with multiple linear regression (MLR) models to predict TPC and an estimative of the OS of cv. Cobrançosa oils extracted at different malaxation temperatures (22 to 34 °C). For the potentiometric analysis, the oils’ polar phenol fraction was extracted with n-hexane and an aqueous methanolic solution (MeOH/H2O 80:20 v/v). The E-tongue-MLR models, based on sub-sets of 11 non-redundant sensors selected using the simulated annealing algorithm, allowed predicting (repeated K-folds-CV) the TPC (175

2020Conference object

Open access

Combined action of dietary-based approaches and therapeutic agents on cholesterol metabolism and main related diseases

Publication . Baptista, Eugénia; Pereira, Cláudia S.G.P.; García, Pablo A.; Ferreira, Isabel C.F.R.; Barreira, João C.M.

Dyslipidaemia is among the major causes of severe diseases and, despite being wellestablished, the hypocholesterolaemic therapies still face significant concerns about potential side effects (such as myopathy, myalgia, liver injury digestive problems, or mental fuzziness in some people taking statins), interaction with other drugs or specific foods. Accordingly, this review describes the latest developments in the most effective therapies to control and regulate dyslipidaemia. Scope and approach: Herein, the metabolic dynamics of cholesterol and their integration with the current therapies: statins, bile acid sequestrants, fibrates, niacin, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, reconstituted high-density lipoprotein (rHDL), or anti-inflammatory and immunemodulating therapies), were compared focusing their effectiveness, patients’ adhesion and typical side-effects. Likewise, the interaction of these therapies with recommended dietary habits, focusing functional foods and nutraceuticals uptake were also considered. Key findings and conclusions: Since none of the current therapeutic alternatives represent an ideal solution (mainly due to side-effects or patients’ tolerance), the potential adjuvant action of selected diets (and other healthy habits) was proposed as a way to improve the cholesterol-lowering effectiveness, while reducing the adverse effects caused by dose-increase or continuous uptake of alternating therapeutic agents. In general, the relevance of well-adapted diets must be acknowledged and their potential effects must be exhorted among patients, who need to be aware of the associated multifactorial advantages.

2025Journal article

Restricted access

Effect of malaxation temperature on olive oil chemical and sensory profiles and their evaluation using an electronic tongue

Publication . Marx, Ítala; Rodrigues, Nuno; Veloso, Ana C.A.; Casal, Susana; Pereira, J.A.; Peres, António M.

Olive oil is highly appreciated due to its nutritional and organoleptic characteristics. Olive oils rich in bioactive compounds can be obtained by optimizing the time and temperature of the malaxation process. In this sense, this study aimed investigating the effect of the malaxation temperature (22 to 34°C) on the olive oil's physicochemical and sensory quality and, in more detail, on the phenolic profile. So, virgin olive oils were produced (November 2018), using olives from cv. Cobrancosa. Furthermore, the possibility of using an electronic tongue, i.e., a multisensor potentiometric device, comprising non-specific lipid polymeric with cross-sensitivity sensor membranes, to monitor the malaxation temperature influence on the olive oil's quality and phenolic composition, was evaluated. For that, multivariate statistical tools were developed for discriminating the olive oils according to the malaxation conditions as well as to predict some key quality parameters, including the extinction coefficients (K232, K268 and |ΔK|), free acidity, oxidative stability, peroxide value, bitterness index, total phenols, phenolic composition and gustatory-retronasal positive attributes. The study aims to determine the best malaxation temperature as well as to assess the versatility of the electronic tongue as a single-run, fast and cost-effective analytical device for olive oils quality evaluation.

2019Conference object

Open access