Search results

The purpose of this paper is, first, to evaluate the quality of commonly consumed fish species in Fez region (Morocco) by quantifying the levels of histamine in fresh fish samples using competitive enzyme-linked immune sorbent assay (ELISA), and then to study the effect of heating and enzymatic digestion on the level of fish-histamine.

Histamine content was tested on 80 fresh fish samples of 11 species collected from various local stores in Fez region, from February to March 2016. The analyses were performed using a competitive ELISA assay to measure histamine in fish samples.

ELISA results showed that 80 percent of 80 fish samples analyzed was found to contain much lower levels of histamine (<1 mg/kg) and can be considered to be safe for human consumption. However, 20 percent of the samples (16/80) had histamine level higher than the tolerance limit of 200 mg/kg established by Moroccan and International regulations, which the maximum level reached up to 7,331 mg/kg in horse mackerel. Concerning the effect of heating and enzymatic treatments on fish-histamine levels, results have shown a low reduction in histamine contents in the majority of fish samples under these treatments.

In conclusion, good quality of the fish product, demonstrated by histamine levels, was found in the most of fish samples analyzed, while 20 percent of the samples are non-compliant and exceed the tolerance limit established by the national and international regulatory limit.

This paper aims to estimate the level of histamine in fish and fish products, as it is very important because of their implication in fish poisoning in humans; hence, ascertaining histamine levels in the aforementioned serves as a chemical index for spoilage.

A technique was developed to immobilize an ordered multilayer of diamine oxidase (DAO) by means of chemical cross-linking on the biconical taper surface stepwisely alternating between chitosan, glutaraldehyde and the enzyme. A spectrophotometric signal results from horseradish peroxidase catalyzed reduction of H₂O₂, a secondary product of the oxidative deamination of histamine monitored at 450 nm.

The biosensor showed a linear response range up to 1.5 mM, a good sensitivity of 0.64 mM-1 with detection and quantification limits towards histamine of 0.086 mM (15.8 ppm) and 0.204 mM (37.7 ppm) and a linear response range of 0-1.5 mM. It showed a response and recovery time of 14 sec and operational stability up to 40 repeated analyses without significant loss of sensitivity.

The developed biosensor has a good potential for use in the quantitative determination of histamine in seafood.

The paper described an outcome of an experimental work on tapered fibre optics (taper)-based biosensor coated with DAO embedded into a chitosan membrane to measure histamine.

Polyphenols possess anti-allergic activities. Catechin is one of the polyphenols that are abundantly present in the Acacia catechu. In this study, the authors investigated the effect of catechin isolated from A. catechu in an experimental mouse model of ovalbumin (OVA)-induced allergic asthma.

Catechin was isolated from A. catechu, and phytochemical analysis was carried out by ultraviolet visible and thin-layer chromatography (TLC), high pressure thin-layer chromatography was used for the determination of an amount of catechin present. In a first set of an experiment, the authors have carried out dose-dependent evaluation of catechin on histamine synthesis in normal rats. In another study, allergic asthma was induced in BALB/c mice by intraperitoneal injection of 50 mg OVA dissolved in 4 mg aluminum hydroxide dissolved in 0.2 ml saline on Days 0 and 14. Catechin was given orally at the dose of 100 mg/kg, once a day from Day 1 to Day 35 and after which various respiratory parameters such as tidal volume, respiratory rate and airflow rate, biochemical parameters such as histamine release from mast cells, bronchoalveolar (BAL) lavage fluid analysis and histopathology of lungs were carried out.

Catechin showed significant (p < 0.05) improvement in respiratory parameters such as tidal volume, respiratory rate and airflow rate, as well as biochemical and hematological parameters such as blood histamine, serum bicarbonate and nitric oxide levels as compared to the disease control group. The treatment also showed inhibitory effects on histamine synthesis in rat peritoneal as well as BAL mast cells. Also, a significant (p < 0.05) improvement in lung histopathology was observed with catechin.

From the present study, the authors can conclude that catechin exhibited potent anti-allergic activity by inhibition of histamine synthesis by inhibition of histidine decarboxylase enzyme. The study suggests that catechin has therapeutic potential for the treatment of allergic inflammatory disease in humans.

The purpose of this paper is to describe a capacitive biosensor device consisting of an enzyme electrode and a simple detector which has been developed for histamine measurement.

In this analysis, degradation of histamine through enzymatic reaction produces signal that is monitored using a simple detector equipped with “astable” multivibrator operation circuit (in capacitor‐resistor circuit).

Different frequency (f) readings have been obtained for glucose, alcohol and histamine in different concentration levels, showing the ability of this simple device system to measure their dielectric constant (k) as formulated by the equation f=(1.44d)/ [kA (R1+2R2)]. The analysis using smaller electrode gap (d) produces higher value of f, indicating that d, is directly proportional to f. For histamine, by using immobilized enzyme electrode, the results show that the change of dielectric properties during the 300‐second reaction period could also be monitored. A linear relationship is obtained between concentration and frequency from 50 to 200 ppm.

Based on this result, an enzyme electrode and “astable” operation circuits have the potential to be used in the development of a simple capacitive biosensor device.

The paper is an outcome of experimental work carried out to observe capacitive sensing behavior using an immobilized enzyme, to measure biological samples, especially histamine.

This study aims to investigate the potential of pumpkin seed oil (PSO) and zinc to attenuate oxidative stress and neuroinflammation caused by chronic mild stress (CMS) in the cerebral cortex of male rats.

The rats were submitted to stress for six weeks and then the behavior of the rats was tested by forced swimming test (FST) and novel cage test. The treated groups were given venlafaxine (20 mg/kg), pumpkin seed oil (40 mg/kg) and zinc (4 mg/kg). The cortex homogenate was used for the detection of the oxidative stress parameters, the concentration of neurotransmitters, tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β), Na+/K+-ATPase activity, and the expression of histamine N-methyltransferase (Hnmt) and tyrosine hydroxylase (Th).

CMS causes a significant increase in immobility time in the FST and a significant decrease in the number of rearing in the novel cage test. CMS group showed a significant increase in alanine aminotransferase (ALT) activity, levels of cortisol, TNF-α, IL-1β, nitric oxide and malondialdehyde. CMS caused a significant decrease in the concentrations of serotonin, GABA, norepinephrine, and the activities of glutathione peroxidase, catalase, superoxide dismutase and Na⁺/K⁺-ATPase. CMS caused a marked reduction in the expression of Hnmt and Th in the cortex. PSO and zinc attenuated the Na⁺/K⁺-ATPase activity, oxidative parameters and neuroinflammation induced by the CMS, and this was reflected by the elevation of the concentration of neurotransmitters and reduction of cortisol and ALT, in addition to the behavior normalization. PSO and zinc attenuated the CMS by improving the antioxidant milieu and anti-inflammatory status of the cerebral cortex.

There are no studies on the effect of pumpkin seed oil on depression

The purpose of this paper is to study the effect of chronic consumption of fresh palm oil (FPO) and thermoxidized palm oil (TPO) diet on gastric acid secretion, pepsin secretions, gastric mucus output and gastric cytoprotection.

Adult Wistar rats were randomly assigned into three groups, i.e. control, FPO and TPO groups (n = 10 in each). The control group was fed with normal rat chow only, the FPO group was fed on diet containing 15 per cent v/w FPO and the TPO group was fed with diet containing v/w of thermally oxidized palm oil. All animals had free access to feed and water, and the feeding lasted for 14 weeks. At the end of the feeding period, gastric acid secretion, pepsin secretion, mucus output and gastric ulceration were measured following standard methods.

There was increase in histamine-stimulated gastric acid output in the TPO diet-fed group (p < 0.01) compared with the control and FPO diet-fed groups. No significant change in the mucus output was observed across all the experimental groups; whereas, pepsin secretion was significantly higher (p < 0.05) in the TPO diet-fed group (0.46 ± 0.27) compared with the control (0.14 ± 0.05) and FPO diet-fed groups (0.25 ± 0.01). Ulcer scores in the TPO diet-fed group (15.5 ± 0.33) was significantly higher (p < 0.01) compared with the control (10.0 ± 0.05) and FPO diet-fed (5.0 ± 0.04) groups.

Chronic consumption of TPO increased gastric acid and pepsin secretion (gastric-aggressive factors) without a change in the mucus output. This can bring about gastric ulceration; therefore, the liberal use of TPO should be discouraged.

Covers the quantitative and qualitative aspects of micro‐organisms present in fish and the factors which affect sea food quality. Several methods can be employed to counter deterioration ‐ low temperature, storage, dehydration, canning, modified atmosphere, packaging, irradiation and chemical or biological preservatives.

“Consumerism”, for want of a better description, is given to the mass of statutory control (which shows no sign of declining) of standards, trading justice to the consumer, means of redress to those who have been misled and defrauded, advice to those in doubt; and to the widespread movement, mostly in the Western world, to achieve these ends.

Human diet consists of an enormous variety of both plants and animal proteins, many of which are potentially immunogenic. Industrial processing of foods and digestion in the gastrointestinal tract causes changes and breakdown of proteins into peptides, which are also potential immunogens. Foods commonly known to cause allergic reactions are fish, milk, eggs, fruits, vegetables, nuts, legumes and meat. Once sensitised to a particular antigen, subsequent exposure may result in a marked and immediate reaction characterised by vomiting, diarrhoea, abdominal cramps, itching and swelling of the mouth and skin, dizziness and occasionally systemic anaphylaxis. Allergic reactions involve complex processes and interactions between the allergen and immunological components in the digestive tract such as antigen absorption, processing and presentation, T cell and B cell activation, development of oral tolerance or allergic sensitivity, antigen‐specific IgE antibody synthesis. Allergen binding to allergen‐specific mast cell membrane‐bound IgE antibodies triggers mast cell degranulation. This results in the release of histamine and other chemotactic mediators responsible for clinical symptoms.