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Abstract

The aims of this study were to prepare butter and honey flavoured tiger nut oil oleogels with beeswax oleogelator and to compare them with the unflavoured control sample. The oleogels prepared with 10 wt% beeswax and 0.5 wt% of each flavour addition were analysed for main physicochemical, thermal, and structural properties. In addition, a trained panel described the samples with 11 sensory descriptive (hardness, spreadability, roasted, liquefaction, rancid, waxy, nutty, butter, honey, cooling, and mouth coating) terms. It was found that the oleogels melt around 52 °C and included β′ type polymorphs. The sensory data proved that the samples were quite well spreadable and had enough hardness to stay as solid-fat samples at room temperature. Further, addition of butter and honey flavours masked the waxy attribute. In conclusion, flavoured tiger nut oil-beeswax oleogels were new and successful products, and future studies with food applications are suggested.

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Abstract

In the presented research, oleosomes were obtained from unroasted hazelnuts in an aqueous environment with a pH of 9.5, adjusted using sodium bicarbonate. Model emulsions were then prepared to contain oleosomes in proportions of 15, 25, and 35%. Rheological and viscosity analyses were conducted on these model emulsions, focusing on elastic and viscous modulus values. The results of the analyses, which revealed that an increase in the oleosome content in the model emulsions correlated with a concurrent increase in emulsion viscosity as well as in the elastic (G′) and viscous (G″) moduli, demonstrate the significant impact of oleosome concentration on the rheological properties of the emulsions. All samples exhibited a G′ > G″ relationship, indicating their semi-solid nature. Moreover, an increase in the oleosome content was found to result in a higher consistency index for the product, while the flow index remained largely unchanged.

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Abstract

Blends of germinated maize and germinated lentil (100:0, 85:15, 70:30, 55:45, and 40:60) were utilised for preparation of chips by air frying. Higher contents of protein, ash, total phenols, flavonoids and antioxidant activity were confirmed in germinated flours through analysis of FTIR spectra. Doughs from blends containing higher amounts of germinated lentil flour showed improved viscoelastic behaviour indicating better protein network as compared to maize dough. Significant (P ≤ 0.05) variation was observed in colour and hardness of air fried chips prepared from various blends. The 70:30 blend was found most acceptable based on sensory evaluation. Chips from this formulation were found superior to ungerminated maize chips in terms of protein digestibility and mineral composition.

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Abstract

Nanoparticles can be synthesised by several methods. Due to the long duration, high cost, and toxic by-products of chemical and physical methods, the biological method has become more preferred. Among various sources such as bacteria, fungi, or yeast, the use of plants in biological synthesis has proven to be the most ideal. Many metals can be used in the biological method, including copper oxide (CuO). In this study, copper oxide nanoparticles (CuONPs) were synthesised using Pimpinella anisum L. aqueous extract. For characterisation of the CuONPs, UV–Visible Spectroscopy (UV–Vis), Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FT-IR) analyses were performed. The biological activity of the P. anisum extract and CuONPs was determined using DNA cleavage (agarose gel electrophoresis), antioxidant (1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and hydrogen peroxide scavenging activity), mutagenic (Ames/Salmonella test), and catalytic (methylene blue degradation) activities. In DNA cleavage activity test, CuONPs completely denatured DNA at high concentrations (100 and 200 μg mL−1) due to their oxidative activity. The results showed that both the extract and CuONPs have antioxidant properties in DPPH and hydrogen peroxide scavenging activities. According to the mutagenicity, CuONPs did not have a mutagenic effect. In catalytic activity, CuONPs degraded methylene blue within 240 min by 99.45%.

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Abstract

In this study, the odour values of rosemary, mint, black cumin, lavender, and thyme oils were determined by an electronic nose working with an Arduino microprocessor. The components of the plants were compared with the sensor data, and the most sensitive sensors were determined by sorting according to the highest components. The study data indicated that the MQ3 sensor exhibited the highest sensitivity for thyme, black cumin, and lavender oils, which contain 63% carvacrol, 38% thymoquinone, and 36% linalool, respectively. Also, MQ7 was the most sensitive sensor for menthone (68%) in mint oil and eucalyptol (45%) in rosemary oil. In addition, a low-cost and non-contact device that works with an infrared sensor has been developed to detect the identity of the oil added into the vial. The study data showed that low-cost Arduino-based IR and odour sensors can determine the identity and component percentage of oils. The fact that the developed device can detect with 100 percent accuracy even in case of peppermint and rosemary oils, which are very similar in appearance, shows that the study data will be an inspiration for contactless determination of oil quality and type.

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Abstract

The effect of different drying methods (oven drying, fluid bed drying, and freeze drying) on the fatty acid composition, astaxanthin content, antioxidant activity, and colour values of giant red shrimp (Aristaeomorpha foliacea) processing wastes were investigated. These results showed that freeze drying was the most effective method in preserving the quality of shrimp processing waste (SPW), resulting in higher levels of EPA and DHA, astaxanthin content, antioxidant activity, and desired reddish colour characteristics compared to other methods. These findings highlight the potential of freeze drying as a suitable technique for converting SPW into high value products.

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European Journal of Microbiology and Immunology
Authors:
Juan Diego Ribeiro de Almeida
,
Raissa Sayumy Kataki Fonseca
,
Naira Sulany Oliveira de Sousa
,
Ana Cláudia Alves Cortez
,
Emerson Silva Lima
,
Juliana Gomes de Souza Oliveira
,
Érica Simplício de Souza
,
Hagen Frickmann
, and
João Vicente Braga de Souza

Abstract

Background

The rising prevalence of fungal infections and challenges such as adverse effects and resistance against existing antifungal agents have driven the exploration of new antifungal substances.

Methods

We specifically investigated naphthoquinones, known for their broad biological activities and promising antifungal capabilities. It specifically examined the effects of a particular naphthoquinone on the cellular components of Candida albicans ATCC 60193. The study also assessed cytotoxicity in MRC-5 cells, Artemia salina, and the seeds of tomatoes and arugula.

Results

Among four tested naphthoquinones, 2,3-DBNQ (2,3-dibromonaphthalene-1,4-dione) was identified as highly effective, showing potent antifungal activity at concentrations between 1.56 and 6.25 μg mL−1. However, its cytotoxicity in MRC-5 cells (IC50 = 15.44 µM), complete mortality in A. salina at 50 μg mL−1, and significant seed germination inhibition suggest limitations for its clinical use.

Conclusions

The findings indicate that primary antifungal mechanism of 2,3-DBNQ might involve disrupting fungal membrane permeability, which leads to increased nucleotide leakage. This insight underscores the need for further research to enhance the selectivity and safety of naphthoquinones for potential therapeutic applications.

Open access

Abstract

Tigecycline-resistant Acinetobacter baumannii (TRAB) is increasing in Thailand, complicating antibiotic treatment due to limited antibiotic options. The specific resistance mechanism behind tigecycline resistance is still unclear, necessitating further investigation. We investigated the presence of OXA-type carbapenemases, the antimicrobial susceptibility profile, the inhibitory effect of carbonyl cyanide m-chlorophenylhydrazone (CCCP) on tigecycline susceptibility, the expression levels of RND-type efflux pumps and amino acid substitutions within a two-component regulatory system on 30 Thai clinical isolates. Our investigation revealed that most of (73.3%) TRAB isolates expressed at least one member of the Ade efflux pumps. The ade B was most frequently expressed (63.3%), followed by ade R (50%), ade S (43.3%), ade J (30%) and ade G (10%). Overexpression of the AdeABC was associated with increased tigecycline minimum inhibitory concentrations (MICs) and amino acid substitutions within the AdeRS. Notably, isolates harbouring simultaneous mutations in these genes exhibited an increase in the transcription level of the ade B. Our findings highlight the significant role of the AdeABC system in tigecycline resistance among Thai clinical TRAB isolates. This is supported by point mutations within the AdeRS and upregulated expression of the ade B. These results provide valuable insights for understanding resistance mechanisms and developing novel therapeutic strategies.

Open access

Abstract

The present work aimed to study the yeast communities of whole crop corn silages (CS) that were previously contaminated with aflatoxin-producing Aspergillus flavus (CSCA). In addition, the effect of lactic acid bacterium (LAB) inoculation on the aflatoxin B1 (AFB1) content, genotoxicity, yeast load, and diversity of yeast communities were also investigated. In A. flavus contaminated silages, after two months, the AFB1 content was 40% lower with LAB inoculation, also a lower level of genotoxicity was determined. The number of yeasts cultured from the initial mixture of chopped whole crop corn was 4.8 × 107 CFU g−1 wet mass, while only 2.4 × 106 CFU g−1 from the CSCA and 7.1 × 105 CFU g−1 from the LAB-inoculated CSCA could be cultured. Based on 144 randomly isolated strains, the yeast community of the initial mixture consisted of 8 species. In contrast, the yeast community of CSCA consisted only of 4 species determined by 132 randomly selected isolates. LAB-inoculated CSCA consisted also of 4 species based on 158 randomly isolated strains. Saccharomyces cerevisiae and Pichia kudriavzevii proved to be predominant in the CSCA, while S. cerevisiae and Meyerozyma guilliermondii were the most abundant in the LAB-inoculated CSCA. The species richness was also confirmed by alpha diversity values (1.827, 1.188, and 1.123 as Shannon's indices for CS, CSCA, and LAB-inoculated CSCA, respectively). In response to LAB inoculation, the species diversity decreased considerably.

Open access

Abstract

This study aims to predict drought periods affecting the Tokaj-Hegyalja wine region and the application of this in crop protection. The Tokaj-Hegyalja wine region is the only closed wine region in Hungary with a specific mesoclimate and a corresponding wine grape variety composition, in which climate change strongly threatens cultivation. The probability that a randomly selected day in the vegetation period will fall into a drought period in the future was estimated using the daily precipitation amount and daily maximum temperature data from the Hungarian Meteorological Service for the period 2002–2020. The Markov model, a relatively new mathematical method for the statistical investigation of weather phenomena, was used for this. Markov chains can, therefore, be a valuable tool for organizing integrated pest management. This can be used to plan irrigation, control fungal pathogens infecting the vines, and plan the success of a given vintage.

Open access