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Abstract

The aim of this study was to optimise the microencapsulation efficiency of propolis phenolic compounds by double emulsion solvent evaporation technique (W1/O/W2). The solvent/sample ratio and the polymer and surfactant concentration parameters were optimised using response surface methodology (RSM) through Box–Behnken Design (BBD). For each parameter studied, total phenolic content encapsulation efficiency (TPCEE), free radical scavenging activity (DPPH), and ferric reducing antioxidant power (FRAP) were evaluated. The results showed that the optimal parameters were: 31.60 mg mL−1 for sample/solvent ratio, 606.28 mg mL−1 for poly(ε-caprolactone) (PCL) concentrations, and 2.05 g mL−1 for poly(vinyl alcohol) (PVA) concentration. The optimum values obtained were: 84.62% for encapsulation efficiency of phenolic content, 51.89% for DPPH, and 48,733 mg Trolox Equivalent/100 g dry weight for FRAP. The experimental checking of results revealed the validity of elaborated models and their suitability for the prediction of both responses. The developed mathematical models have expressed a high level of significance through RSM optimisation processes for phenolic antioxidants of propolis.

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Abstract

Platycranus metriorrhynchus Reuter, 1883, the first representative of the predominantly Holomediterranean plant bug genus, Platycranus Fieber, 1870 is reported as a new element of the Hungarian true bug fauna. Diagnostic characters and bionomics of the species are discussed.

Open access

Abstract

“Feed the global population and regenerate the planet.”

The conditions necessary for the implementation of the above commonly used slogan did not exist 10–15 years ago. We did not have access to the information and databases that would have allowed us to increase yields for the purpose of feeding the growing population. While increasingly meeting sustainability requirements and regenerating the Earth. Anthropocentrism, the belief that humans are superior to everything else, benefits humans by exploiting human greed and ignorance, which is a dead end for both individuals and societies. Only humans can ignore the dynamic equilibrium processes of nature and disregard the consequences that adversely affect future generations. Ecocentric agricultural practices have several prerequisites. It is important for the academic sphere to recognize its significance. Another fundamental challenge is the continuous monitoring of the production unit and its close and distant environment for the purpose of decision preparation using Big Data. The Internet of Things (IoT) is a global infrastructure that represents the network of physical (sensors) and virtual (reality) “things” through interoperable communication protocols. This allows devices to connect and communicate using cloud computing and artificial intelligence, contributing to the integrated optimization of the production system and its environment, considering ecocentric perspectives. This brings us closer to the self-decision-making capability of artificial intelligence, the practice of machine-to-machine (M2M) interaction, where human involvement in decision-making is increasingly marginalized. The IoT enables the fusion of information provided by deployed wireless sensors, data-gathering mobile robots, drones, and satellites to explore complex ecological relationships in local and global dimensions. Its significance lies, for example, in the prediction of plant protection. The paper introduces small smart data logger robots, including the Unmanned Ground Vehicles (robots) developed by the research team. These can replace sensors deployed in the Wireless Sensor Net (WSN).

Open access

Abstract

Human infections with the food-borne zoonotic enteropathogen Campylobacter jejuni are increasing globally. Since multi-drug resistant bacterial strains are further on the rise, antibiotic-independent measures are needed to fight campylobacteriosis. Given its anti-microbial and anti-inflammatory properties the polyphenolic compound resveratrol constitutes such a promising candidate molecule. In our present placebo-controlled intervention trial, synthetic resveratrol was applied perorally to human gut microbiota-associated (hma) IL-10−/− mice starting a week before oral C. jejuni infection. Our analyses revealed that the resveratrol prophylaxis did not interfere with the establishment of C. jejuni within the murine gastrointestinal tract on day 6 post-infection, but alleviated clinical signs of campylobacteriosis and resulted in less distinct colonic epithelial apoptosis. Furthermore, oral resveratrol dampened C. jejuni-induced colonic T and B cell responses as well as intestinal secretion of pro-inflammatory mediators including nitric oxide, IL-6, TNF-α, and IFN-γ to basal levels. Moreover, resveratrol application was not accompanied by significant shifts in the colonic commensal microbiota composition during campylobacteriosis in hma IL-10−/− mice. In conclusion, our placebo-controlled intervention study provides evidence that prophylactic oral application of resveratrol constitutes a promising strategy to alleviate acute campylobacteriosis and in consequence, to reduce the risk for post-infectious autoimmune sequelae.

Open access

Abstract

Hungary is a Central European country that is rich in medicinal and aromatic wild plant species; in rural livelihoods, the collection, use, process, and trade of these plants are traditionally important contributors. However, due to several recent changes touching the sector, the natural ecosystems, biodiversity, and collectors - who generally belong to poorer social groups – are affected negatively.

The paper aims to introduce the Hungarian herbal sector from a holistic perspective, including its economic, environmental, and human dimensions, with a particular focus on sustainability. In this context, the purpose of the article is to discover this field as comprehensibly as possible and present it from both theoretical and practical aspects. Another objective is to collect the best practices and feasible solutions from the field in connection with promoting a harmonious, as well as economically prosperous relationship between nature and local people. This integrated approach helps show the industry's strengths and advantages, as well as its weaknesses and challenges. Based on the findings, the paper attempts also to propose some recommendations for the future.

Open access
Acta Alimentaria
Authors:
X. Bai
,
H.F. Gao
,
X. Li
,
Y.L. Li
,
M.Z. Lan
,
L. Li
,
Z.D. Zhao
,
Z.B. Li
, and
J. Wang

Abstract

As research advances, it is generally acknowledged that non-Saccharomyces yeast contribute to the addition of aromatic compounds during mead fermentation. In this experiment, eight different non-Saccharomyces strains and Saccharomyces cerevisiae co-fermentation, their aroma composition, and basic physicochemical parameters were investigated. More than 30 compounds with favourable impact were discovered using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Co-fermentation of non-Saccharomyces spp. and S. cerevisiae can affect the concentration of volatile compounds, so that the mead presents different aroma characteristics. Co-fermented meads of Wickerhamomyces anomalus strains and S. cerevisiae (Wa 27-Sc and Wa 5-Sc) had higher alcohol, acids, aldehyde, and ester concentrations than those fermented with S. cerevisiae alone. In terms of taste, Wa 27-Sc was superior to Wa 5-Sc. Overall, the Wa 27-Sc received the highest score for its strong secondary aroma and good mouthfeel. The results show that the W. anomalus Wa 27 strain has a good potential to produce high quality mead.

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Abstract

The study investigates the antimicrobial effects of the Hypericum crenulatum ethanolic (HCE) extract against 14 different food pathogens and their biofilm-forming abilities in response to HCE treatment. The phenolic acid composition of the HCE extract was also determined using an HPLC-DAD detector. The antimicrobial activity of HCE extract was assessed using the disc diffusion and microdilution methods. According to the findings, the methicillin-resistant Staphylococcus aureus ATCC 43300, Listeria monocytogenes RSKK 472, and Listeria innocua ATCC 33090 strains exhibited the lowest minimum inhibitory concentration (MIC) values at a concentration of 2 μg mL−1. Based on the disc diffusion test results, the largest zone of inhibition of HCE extract against foodborne pathogens was seen against Bacillus cereus, and the diameter of the inhibition zone increased with the concentration of HCE extract (P < 0.05). In terms of phenolic acid composition of HCE extract, the phenolic acids with the highest and lowest amounts were caffeic acid (59.92 mg g−1) and p-coumaric acid (13.61 μg g−1), respectively. Our study determined that the HCE extract demonstrated antimicrobial, bactericidal, and antibiofilm activities against some foodborne pathogens. These effects reveal its potential for improving food safety by inhibiting the growth of these pathogens.

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„Két lábbal a földön, avagy miként próbál a talajtan válaszokat adni a globális kihívásokra”

Beszámoló a HUN-REN ATK Talajtani Intézetének Magyar Tudomány Ünnepe előadónapjáról

Agrokémia és Talajtan
Author:
Kitti Balog
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Progress in Agricultural Engineering Sciences
Authors:
Donald Bimpong
,
Lois Amponsah Adofowaa
,
Ama Agyeman
,
Abena Boakye
,
Ibok Nsa Oduro
,
Ellis William Otoo
, and
John-Lewis Zinia Zaukuu

Abstract

Peanut butter and yoghurt are targeted for adulteration intended at consumer deception. This study aimed to fingerprint and detect peanut butter and yoghurt adulteration with cassava flour and starch using Near Infrared Spectroscopy (NIRS) in a quasi-experimental approach. Ingredients for laboratory sample preparation were obtained from the Kumasi Metropolis. Peanut butter was adulterated at 1, 3, 5, 10, 15, 20% w/w and yoghurt at 0.25, 0.5, 1, 3, 5, 10, 15, 20, 25, 45, 50% w/w. Selected concentrations mimicked practices on the market. Marketed products were randomly sampled from six markets in the Kumasi Metropolis to validate the study models. Samples were scanned with a hand-held NIRS in triplicates. Chemometric (Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Partial Least Square Regression (PLSR) models) statistical methods were employed to develop classification and prediction models. Peaks with spectral bands such as 1050 , 1200 and 1450 nm were observed for peanut butter and 990–1100 nm, 1100–1200 nm and 1300–1408 nm were observed for yoghurt in the NIR spectrum. Some yoghurt brands were suspected of containing cassava starch, while Peanut butter from the different markets differed based on classification models. Cassava flour and starch concentrations were quantitatively predicted by PLSR with an R2 CV of 0.98 and an error of 0.9 g/100 g (low error).

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European Journal of Microbiology and Immunology
Authors:
Ellis Kobina Paintsil
,
Wycliffe O. Masanta
,
Annika Dreyer
,
Leonid Ushanov
,
Stella I. Smith
,
Hagen Frickmann
, and
Andreas E. Zautner

Abstract

Campylobacter infections and campylobacteriosis-associated post-infectious sequelae are a significant global health burden that needs to be addressed from a specific African perspective. We conducted a comprehensive literature search on NCBI PubMed to compile a comprehensive narrative review article on Campylobacter infections in Africa, focusing on key aspects in human and veterinary medicine as well as food hygiene. We specifically focused on the epidemiology of enteropathogenic Campylobacter spp. in sub-Saharan and North Africa considering antimicrobial susceptibility. The most significant sequela resulting from molecular mimicry to Campylobacter surface structures is the Guillain-Barré syndrome, which was mainly examined in the context of limited studies conducted in African populations. A dedicated subsection is allocated to the limited research on the veterinary medically important species Campylobacter fetus. There are significant differences in the composition of the gut microbiome, especially in rural areas, which affect the colonization with Campylobacter spp. and the manifestation of campylobacteriosis. There may be a problem of overdiagnosis due to asymptomatic colonization, particularly in the detection of Campylobacter using molecular biological techniques. To reduce the colonization and infection rate of Campylobacter, we propose implementing several control measures and urge further research to improve the current understanding of the peculiarities of campylobacteriosis in Africa.

Open access