Categoría: Results

New INL publication on techniques for rapid detection of pathogenic microorganisms in foods

A new article related to the detection of E. coli O157 has been accepted. On this occasion, the INL researchers have developed an isothermal technique (RPA) combined with a sample treatment that allows the detection of the bacteria on the same day the analysis is started, being able to see the result with the naked eye by color change, or with the help of a UV lamp.

This new article is added to others that INL has been publishing throughout SEAFOOD-AGE project with the support of FEDER funds through the INTERREG Atlantic Area Programme:

Video tutorials developed by IPMA instruct on how to assay biological activity of compounds

During the 1st training session organised by TQC on 4th November, the Portuguese Institute of Sea and Atmosphere (IPMA) showed the different methods to assess the bioactivity of ingredients. This action was intended to familiarize the partners with techniques and processes that can be carried out at lab. IPMA’s presentation was supported by a series of video tutorials developed by them in the framework of SEAFOOD-AGE project.

Now, these videos are available through SEAFOOD-AGE Youtube channel for any researcher or technician interested in these techniques:

How to obtain extracts from the algae Alaria esculenta in the lab?

How to assay in the laboratory the reducing power of biological compounds?

How to assay in the laboratory the chelating activity of biological compounds?

How to assay in the laboratory the antioxidant activity of biological compounds?

How to assay in the laboratory the anti-obesity activity of biological compounds?

How to assay in the laboratory the anti-hypertensive activity of biological compounds?

How to assay in the laboratory the antidiabetic activity of biological compounds?

First paper released by IPMA and IIM-CSIC in the framework of SEAFOOD-AGE

Our partners, the Portuguese Institute for the Sea and Atmosphere (IPMA) together with the Marine Research Institute (IIM-CSIC), have just published their first Open access paper in the framework of the project.

With the title «Characterization of Protein Hydrolysates from Fish Discards and By-Products from the North-West Spain Fishing Fleet as Potential Sources of Bioactive Peptides«, this article addresses the evaluation of different bioactivities (antioxidant, chelating, antidiabetic, anti-hypertensive, anti-obesity activities) of fish protein hydrolysates (FPH) as potential natural additives for functional foods or nutraceuticals.

Abstract: Fish discards and by-products can be transformed into high value-added products such as fish protein hydrolysates (FPH) containing bioactive peptides. Protein hydrolysates were prepared from different parts (whole fish, skin and head) of several discarded species of the North-West Spain fishing fleet using Alcalase. All hydrolysates had moisture and ash contents lower than 10% and 15%, respectively. The fat content of FPH varied between 1.5% and 9.4% and had high protein content (69.8–76.6%). The amino acids profiles of FPH are quite similar and the most abundant amino acids were glutamic and aspartic acids. All FPH exhibited antioxidant activity and those obtained from Atlantic horse mackerel heads presented the highest 2,2-diphenyl-1- icrylhydrazyl (DPPH) radical scavenging activity, reducing power and Cu2+ chelating activity. On the other hand, hydrolysates from gurnard heads showed the highest ABTS radical scavenging activity and Fe2+ chelating activity. In what concerns the _-amylase inhibitory activity, the IC50 values recorded for FPH ranged between 5.70 and 84.37 mg/mL for blue whiting heads and whole Atlantic horse mackerel, respectively. _-Glucosidase inhibitory activity of FPH was relatively low but all FPH had high Angiotensin Converting Enzyme (ACE) inhibitory activity. Considering the biological activities, these FPH are potential natural additives for functional foods or nutraceuticals.

Two new papers released by INL in Open Access

Our colleagues from the International Iberian Nanotechnology Laboratory have just published two new articles, both related to the detection of Listeria monocytogenes.

One of them is focused on a method of surface analysis and naked eye detection with lateral flow strips:

Application of Recombinase Polymerase Amplification with Lateral Flow for a Naked-Eye Detection of Listeria monocytogenes on Food Processing Surfaces

The second one develops a method consisting of a multiplex qPCR system to also detect other pathogens, using infant milk as a food model, although applicable to any type of food:

Multiplex Detection of Salmonella spp., E. coli O157 and L. monocytogenes by qPCR Melt Curve Analysis in Spiked Infant Formula

First paper released by INL in the framework of SEAFOOD-AGE

picture provided by INL

Our partner, the International Iberian Nanotechnology Laboratory, is working to improve food safety. They have just published a novel multiplex real-time RPA method for the rapid detection of Listeria monocytogenes:

Comparative study of multiplex real-time recombinase polymerase amplification and ISO 11290-1 methods for the detection of Listeria monocytogenes in dairy products

The development of novel methods for the rapid detection of Listeria monocytogenes is of high interest due to due to particular concerns about this its ubiquity, resistance to sanitation processes and high mortality rates resulting from infection.

The evaluation of a novel multiplex real-time Recombinase Polymerase Amplification (RPA) method including an internal amplification control is reported in the paper released in volume 92 of Food Microbiology. The method performance was compared to that of the European reference method (ISO 11290-1) for the detection of the species in samples from 40 commercial dairy products. A limit of detection below 10 cfu/25 g or mL sample was achieved, and values higher than 90% were obtained for relative sensitivity, specificity, accuracy, positive and negative predictive values and the index (kappa) of concordance. Analysis was achieved within one working day, compared to the six days required using the ISO method. Moreover, slight modification of the ISO 11290-1 method to include secondary enrichment in half Fraser broth resulted in the confirmation of all positive samples.