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Acta Alimentaria
Authors: Cs. Dobolyi, K. Inotai, I. Bata-Vidács, D. Sárkány, O. Csernus, S. Kocsubé, B. Tóth, A. Szekeres, and J. Kukolya

Abstract

Aspergillus strains were isolated from Hungarian mills in order to get information on the appearance of sterigmatocystin (ST) producing moulds, whose presence has never been demonstrated in Hungary. Fungal isolates were classified into nine morphotypes, sections Nigri, Nidulantes, Versicolores (two morphotypes), Circumdati, Flavi (two morphotypes), Clavati and Terrei by classical mycological assays. ST producing strains could be classified into section Versicolores. ST production of the isolates was assessed by liquid and solid phase growth experiments and compared to ST producing reference strains: Aspergillus pepii SzMC 22332, Aspergillus versicolor SzMC 22333, Aspergillus griseoaurantiacus SzMC 22334 and Aspergillus nidulans RDIT9.32. Four of our isolates marked as Km11, Km14, Km26 and Km31 showed ST production in liquid medium. ST production on solid phase corn grit substrate was measured after three weeks of incubation, and Km26 isolate proved to be the most prominent with a toxin concentration of 277.1 μg g−1, surpassing all reference strains. The toxin-producing ability of Km26 isolate was also tested in a field experiment, where corn was infected. By the end of the experiment, ST level of 19.56 μg kg−1 was measured in infected corn.

Molecular taxonomic identification of the Km26 strain was performed using internal transcribed spacer (ITS), calmodulin and tubulin sequence analyses. Based on these studies, strain Km26 was identified as Aspergillus creber.

Here we report that an ST-producing A. creber strain has appeared in Hungary, and the Km26 strain is the first known extreme ST-producing mould in this country. As a result of climate change, aflatoxin B1 producing Aspergillus flavus strains have appeared in Hungary in the last decade. As strain Km26 is the only A. creber isolate in Hungary so far, there is no sign of mass prevalence, and due to the lower temperature optimum of the species compared to A. flavus, its appearance is probably not related to climate change.

Open access

Abstract

In this study, antioxidant, oxidant, antimicrobial, and antiproliferative activities of Asparagus acutifolius L. and Asparagus officinalis L., known for their nutritional properties, were determined. In this context, methanol (MeOH) and dichloromethane (DCM) extracts of plants were obtained. Total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) were determined using Rel Assay kits. Antimicrobial activities of plant extracts were determined against the test microorganisms using the agar dilution method. Antiproliferative activity was tested on the lung cancer cell line A549. As a result of the studies, it has been determined that the plant species have high antioxidant potential. In addition, it was observed that the antifungal potentials of plant extracts are high. Antiproliferative activity was determined to be at high level in both plant species. As a result, it has been determined that A. acutifolius and A. officinalis have medical potential and can be used as natural agents in pharmacological designs.

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Abstract

Tomato is worldwide the most grown vegetable. The primary target of breeding programs is to develop new tomato cultivars that are resistant to pests and diseases, in combination with high quality and yield, well-adaptation and good firmness. Among the different tomato types, cherry and cocktail tomatoes are widely preferred by consumers due to their better taste and appearance. In this study, two female tester lines were crossed with four male lines to obtain new tomato hybrids. The eight F1 hybrids and two commercial hybrids were planted in a randomised complete block design with two replications in a greenhouse in Antalya. The tomatoes of the hybrids and lines were harvested at fully ripened stage to evaluate yield, total soluble solids (TSS), fruit firmness, lycopene content and fruit colour parameters. TSS values of the cultivars and lines ranged from 4.5 to 9.5 °Bx, fruit firmness from 7.94 to 11.85 kg cm−2, lycopene from 52.10 to 55.88 mg kg−1, yield from 554.3 to 1336.7 g/plant. Hybrid AK0020 was found the best for both yield and quality.

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Acta Alimentaria
Authors: K. Berisha, H. Bytyçi, Zs. Mednyánszky, E. Kiss, and L. Simon-Sarkadi

Abstract

To our knowledge, there is a lack of information on the nutrient composition of Busha cattle milk with special regard to its amino acid and biogenic amine contents. The Busha cattle breed is known to be highly resistant to various diseases and well-adapted to the extensive breeding conditions of the Balkan Peninsula. Busha cow milk contains an average of 13.47% dry matter, 4.34% fat, 3.72 % protein, and 4.32% lactose. Significant differences were detected (P < 0.05) in the amino acid compositions of the milk of different Busha cattle strains of Kosovo. Glutamic acid, proline, leucine, aspartic acid, lysine, and valine represented 68% of the total amino acid content. Essential amino acids, branched-chain and sulphur-containing amino acids were found in substantial amounts in the milk samples. Among the biogenic amines, however, spermine (0.16 mg kg−1) and cadaverine (0.09 mg kg−1) were present in low concentrations. Due to these excellent qualities of the Busha cow milk, preservation of this cattle breed is of great importance. Developing sustainable and secured breeding and feeding programs for this endangered cattle breed of the Balkan Peninsula should also be a high priority.

Open access

Abstract

Improvement of nutritive profile of pork sausages was performed by fat reduction and partial substitution of backfat with soybean oil (SBO). The control sausage was made from pork backfat. For the studied samples, SBO in native and pre-emulsified forms was used for partial substitution of backfat at 25% (by wt of backfat) to produce sausages with various fat contents (30, 20, and 10%). Discontinuity of protein matrix could be observed with increasing fat content, especially for addition of pork backfat. Improvement on product stability could be achieved using SBO, especially pre-emulsified form, to partially replace animal fat. Better dispersibility of the SBO droplets through the meat matrix compared to backfat globules was suggested by the greater continuity in the microstructure of the sausages with SBO. For the sausages supplemented with pre-emulsified SBO, the non-meat protein used as emulsifier could further strengthen the protein network, thereby resulting in enhanced product stability and retained textural attributes of the sausages. The fish protein isolate presently employed as emulsifier to prepare SBO emulsion could be promisingly used to produce more nutritive sausages by providing adequate stability.

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Abstract

The effect of high pressure processing (300 and 600 MPa) combined with mild heat treatment (55 and 75 °C) on the colour parameters, anthocyanin content, and sensory characteristics of strawberry puree were examined after the treatments and 2 weeks of cold storage at 2 and 15 °C. As on an industrial scale the simultaneous implementation of these treatments remains a challenge, the HHP and heat treatments were carried out consecutively in different sequences. The colour parameters and the anthocyanin content did not change significantly due to the treatments, but decreased during cold storage, at 15 °C storage the changes were more intensive than at 2 °C. Regarding the sensory test results, the different sequence of the 600 MPa-75 °C combined treatments is not detectable even after 2 weeks of storage at 15 °C, but in case of 300 MPa-55 °C, the enzyme inactivation is probably not sufficient enough as differences between the samples were detected.

Open access

Abstract

Grafting is an effective tool in intensive vegetable growing systems that provides standard quality and yield. In the present study, the effect of two rootstocks (‘Capsifort F1’ and ‘Snooker F1’) on two commercial varieties (‘SV9702 F1’ and ‘Karpex F1’) grown on two media (soil and coconut fibre) was evaluated. During our 2-year study, those instrumental attributes, which have a dominant effect on the chosen chemical components of fruit quality (total soluble solids and titratable acidity) were investigated. Sensory tests were also implemented in order to identify any changes due to the applied technological combinations. Sensory profile analysis was used to identify the descriptive attributes and their perceived intensities. Panellists worked in individual booths with standard lighting, test results were recorded with the Profisens software. In general, it can be concluded that the major instrumental and sensory parameters did not deteriorate as a result of grafting and the application of coconut fibre medium. Some attributes were identified, where the grafted plants on coconut fibre medium showed higher values, namely flesh thickness and shape. Based on our results, grafting and the application of coconut medium is a feasible technological development for growers and agri-business companies.

Open access

Abstract

In this paper, we studied the inhibitory effect of oleanolic acid (OA) on non-enzymatic glycosylation and the improvement of glycometabolism in insulin resistant (IR) human liver tumour (HepG2) cells. The anti-glycosylation activity of OA was determined by bovine serum albumin (BSA) fructose model. The results showed that OA moderately inhibited the formation of the intermediates of non-enzymatic glycosylation, fructosamine and α-dicarbonyl compounds, and strongly inhibited the formation of advanced glycation end products (AGEs). In addition, we analysed the effect of OA on glycometabolism induced by palmitic acid (PA) in HepG2 cells. The results showed that OA had almost no impact on HepG2 cell viability at concentrations lower than 30 µM. With the increase of OA concentration, glucose production in IR HepG2 cells decreased, while glycogen content increased. Meanwhile, OA has a significant inhibitory effect on reactive oxygen species (ROS) levels in IR-HepG2 cells. Those results suggested that OA could be a promising natural blood glucose decreasing substance in the pharmaceutical and functional food industries.

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Abstract

Residues in animal feeds and foods of animal origin have been important safety issue concerning both human and animal health. A multiresidue method for determination of eight mycotoxins and ten antibiotics was developed and validated in animal feeds by using QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction followed by UHPLC-MS/MS. Optimisation of UHPLC-MS/MS parameters was performed to achieve good separation and resolution. The method was validated according to the European Commission Decision 2002/657/EC. Matrix matched calibration curves showed good r 2 (≥0.995) values, and limit of quantification (LOQ) values varied between 1.2 and 5.2 μg kg−1. Average recoveries ranged from 60 to 102% with relative standard deviations of 2.2 and 15.6% for all type of feed samples except for tetracyclines, lincomycin, tylosin, ochratoxin A, and fumonisin (B1 and B2).

Open access

Abstract

The probiotic and technological potentials of lactic acid bacteria originating from human milk are becoming a remarkable research area. In the present study, Limosilactobacillus vaginalis MA-10 isolated from human milk was investigated in vitro for its probiotic and technological aspects. According to the results obtained in the study, MA-10 strain exhibited non-haemolytic activity and various degrees of sensitivity to most of the tested antibiotics. The strain showed good resistance to the gastrointestinal system and maintained its viability under these conditions. Its antimicrobial activity against human or clinical bacterial and fungal microorganisms and fish bacteria was determined in the range of 2.38–11.22 mm. The MA-10 strain was able to assimilate cholesterol ranging from 31.42 to 82.30%. The strain showed 9.34% ferrous-ion chelating and 32% DPPH free radical scavenging activities. These initial results from the present study confirm that L. vaginalis MA-10 may be a new source with appropriated probiotic and technological traits for various industries, and further in vivo assays.Due to the limited number of studies on L. vaginalis strains originated from human breast milk in the literature, the data obtained in this study are thought to be important for revealing the basic probiotic properties of the strain.

Open access