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Abstract

Elderberry pomace, a by-product generated by elderberry processing industries, may be a favourable resource for further utilisation due to its components of high nutritional quality. In our research, elderberry pomace extract (EP) was added to apple juice as natural food additive for controlling microbial spoilage and enriching antioxidant components.

During the 8-week storage period of enriched apple juice (EPA) and control apple juice samples antioxidant properties were evaluated using the FRAP assay, Folin–Ciocalteu method, and pH differentiation method. The amount of polyphenols components was quantified using an RP-HPLC method. The microbiological status of samples was studied by determining the total viable and yeast/mould counts. The EPA is an important source of polyphenol components and other bioactive compounds, and the results suggest that extract of elderberry pomace could be a promising natural preservative to improve microbiological stability during refrigerated storage and increase the quality of apple juice.

Open access
Acta Alimentaria
Authors:
Z.Z. Yang
,
J.Q. Zhang
,
B.B. Shi
,
J.Q. Qian
, and
H. Guo

Abstract

Myricetin has been reported to have a wide variety of beneficial physiological functions. The present study investigated the antihyperlipidaemic activity of myricetin against hyperlipidaemia of high-fat diet-fed obese rats. The four-week antihyperlipidaemic activity was assayed by giving different doses of myricetin to hyperlipidaemic rats. Results showed that myricetin could reduce the harm caused by oxidative stress, decrease thiobarbituric acid reactive substances value, and decrease total cholesterol and triacylglycerol levels of hyperlipidaemic rats. Quantitative analysis of gene expression showed that myricetin's lipid-lowering activity can be activated by downregulating gene expression of fatty acid synthase (FAS) and peroxisome proliferator-activated receptor-γ (PPARγ) with upregulation of hormone-sensitive lipase (HSL) mRNA level. Thus, myricetin had significant health benefits and could be explored as a potentially promising dietary supplement for treating hyperlipidaemia.

Open access

Abstract

Ergosterol, as a precursor for synthesising useful molecules like vitamin D2, possesses significant physiological functions in both fungal and human systems. In fungi, ergosterol plays a crucial role in stress responses. In contrast to Saccharomyces cerevisiae yeast, the changes in specific ergosterol content of Kluyveromyces marxianus under various stress conditions are less known. This study investigated how ergosterol content changes in response to different stress factors. Carbon to nitrogen (C/N) ratio was examined using experimental design. The effects of aeration and shear force beside constant overall volumetric mass transfer coefficient (KLa) were examined. Cell growth and specific ergosterol content were investigated using ethanol stress during a two-stage fermentation. Based on the results, contradictory settings regarding C/N ratio and shear force were found to be favourable for cell growth and specific ergosterol content. However, increased aeration consistently elevated specific ergosterol content and favoured cell growth as well (2.5-fold and 1.5-fold, respectively). In K. marxianus fermentations, higher ergosterol yield can be achieved through a two-stage fermentation (138.9 mg L−1 compared to 52.9 mg L−1), where the first stage provides favourable conditions for cell growth, and the second stage involves stress (beneficial for ergosterol production) conditions. Conclusions drawn from the two-stage fermentation results suggest that early transitioning of cell growth to the second phase will not result higher adaption and specific ergosterol content compared to the transition at the end of exponential growth phase.

Open access

Abstract

The article evaluates how well the goals of the European Green Deal are justified, especially considering the risks to energy and food security arising from the conflict between Russia and Ukraine. We agree with the objectives of the European Green Agreement as a whole, but whether some of the objectives which feature in the EASAC study can be achieved by 2030 is questionable, and the description of the tools necessary to achieve the objectives is incomplete. Among other things, there is hardly any mention of the role played by precision farming with digitalization, which is a revolutionary change from an ecological and economic point of view, in reducing the use of synthetic inputs, in regenerating the original state of the soil, in reducing GHG emissions, thus in increasing biodiversity, and at the same time in intensifying production, and finally in expanding the application of biotechnology. We examine these areas in our analysis. Some of the objectives of the EASAC study to be achieved by 2030 are subject to debate, and the description of the information and communication conditions necessary to achieve the objectives is incomplete. The IoT (Internet of Things) responds to global and local challenges: it integrates the precision technologies, WSNs (Wireless Sensor Networks), artificial intelligence, mobile field (Smart Small Robots) and remote data loggers (UAVs: Unmanned Air Vehicles and satellites), Big Data, and cloud computing. Consequently, decision support is increasingly developing into unmanned decision making. IoT (Internet of Things) is the basis of “Farm to Fork” and “Lab to Field” monitoring approaches.

This article evaluates the implementation of European Green Agreement objectives in light of energy and food security risks arising from the Russia-Ukraine conflict. While overall support for the agreement exists, the feasibility of certain EASAC study objectives by 2030 is called into question due to insufficient tools specifications. Notably absent is the emphasis on precision farming with digitalization, which is a transformative ecological and economic practice. Our analyses look into its function in reducing synthetic inputs, soil regeneration, GHG emission reduction, biodiversity enhancement, production intensification, and biotechnology development. Debates surround EASAC study objectives for 2030, despite limited information and communication restrictions. The Internet of Things (IoT) arises as a solution, combining precision technology, WSNs (wireless sensor networks), AI (artificial intelligence), smart small robots, UAVs (unmanned aerial vehicles), satellites, big data, and cloud computing. As a result, decision support turns toward unmanned decision-making, with IoT laying the groundwork for “Farm to Fork” and “Lab to Field” monitoring systems.

Open access

The use of organic fertilization is declining in Hungary due to the sharp fall of livestock stand since the middle of the 1980s. Most farmers are forced to use solely chemical crop enhancers. A bifactorial small plot experiment was carried out between 10 May 2023 and 19 October 2023 in Keszthely, in order to examine the effects of farmyard manure (M), green manure (GM) and stem residues (SR) on the nutrient uptake and nitrogen utilization efficiencies of maize at equidistantly increasing (0–70–140–210–280 kg N ha–1) nitrogen doses. The relationship between some vegetative traits (dry biomass weight, Leaf Area Index (LAI)) and yield, furthermore leaf relative water content (RWC) was also examined. According to the results, organic fertilizer substitution significantly increased the N content both in whole plant and grain samples of NPK+M and NPK+GM+SR treatments, compared to the chemically fertilized control (NPK). In case of P and K only slight differences were observed. Whole plant K contents of NPK+M were significantly higher than in the other treatments (P = 0.045; P = 0,005), furthermore P contents in grain samples were significantly higher in NPK+M (P = 0.004) and NPK+GM+SR (P = 0.05) than in control. Harvest index (HI [%]) of NPK+M and NPK+GM+SR were 1.06 and 1.05 times higher than in NPK. Depending on the treatment, P0023 maize hybrid absorbed 58.7–74.64% of total N uptake in the grain (HIN%), and the utilization of 1 kg N fertilizer for the extra yield above the yield of the individual control was 0.39–1.38 kg (AREN). Significant positive correlations were observed between dry biomass weight and yield (NPK: r = 0.937, P = 0.019; NPK+M: r = 0.971, P = 0.006; NPK+GM+SR: r = 0.88, P = 0.049), furthermore LAI and yield (NPK: r = 0.9, P = 0.037; NPK+M: r = 0.983, P = 0.003; NPK+GM+SR: r = 0.784, P = 0.117). Highest RWC values – which may be related to better soil aggregate stability – were measured in NPK+GM+SR treatment, therefore there may be a great potential in this treatment among drought conditions. The effect of organic amendments is particularly noticeable with smaller nitrogen doses so they should be used to reduce inorganic fertilizer application and the resulting environmental risks.

Open access

Abstract

Chinese onion (Allium chinense G. Don) is an edible vegetable as well as a traditional Chinese medicine. It is rich in steroidal saponins and possesses broad health benefits. In this study, the optimal extraction protocol of the total saponins from Chinese onion (ACS) was explored, and the content of the total steroidal saponins in ACS reached 56.62%. Network pharmacology was applied to predict the related signalling pathways and targets between the main phytochemicals in ACS and hypercholesterolaemia. Enrichment analysis showed that ACS might intervene hypercholesterolaemia through the PI3K-Akt signalling pathway. Meanwhile, cholesterol-lowering effects were verified by ACS intervention in high-cholesterol diet-induced hypercholesterolaemia in Kunming mice. Compared with the model group, the TC and LDL-C levels of mice were decreased and the HDL-C level increased significantly after administration of ACS at a dose of 200 mg kg−1 day−1. The body weight gain, liver index, and atherosclerosis index all decreased dramatically. ACS could significantly reduce the fat content in the liver and reduce the number of fat droplets from the haematoxylin and eosin (H&E) staining of mouse liver. The immunohistochemical staining indicated that ACS could up-regulate the expression of PI3K protein in the liver, thus playing an anti-hypercholesterolaemic role. This study indicated that ACS exhibited significant therapeutic and preventive effects on hypercholesterolaemia, and exerted anti-hypercholesterolaemia through the PI3K-Akt signalling pathway.

Open access

Abstract

Nutritional problems can be seen in children living separated from their families. This cross-sectional pilot study aimed to evaluate intuitive eating, diet quality, and nutritional status of children living separated from their families. A total of 55 adolescent girls aged 12–18 years participated in the study. Anthropometric measurements, biochemical data, and 24-h dietary recall data were collected. The Intuitive Eating Scale-2 (IES-2) and the Turkish version of the Healthy Lifestyle-Diet (HLD-TR) index were used. Participants were divided into two groups according to their scores on the diet quality index using the 50th percentile. Group 1 consisted of participants with a score of 25 points or less, and Group 2 consisted of participants with a score above 25 points. Waist circumference (72.0 (66–83), 65.0 (60–77)) was significantly higher in Group 1 (P < 0.05). IES–2 score (3.05 (2.85–3.40), 3.30 (3.12–3.90)) and two sub–factors; reliance in hunger and satiety cues (2.80 (1.80–3.40), 4.00 (2.60–4.60)) and body–food choice congruence (2.50 (2.00–3.50), 3.50 (3.00–4.50)) were higher in Group 2 (P < 0.05). After adjustment for body mass index, age, and energy intake, there was a significant positive correlation between IES-2 and HLD-TR scores (P = 0.029). In conclusion, it may be advantageous to resort to strategies that promote intuitive eating to reduce obesity and associated problems in this vulnerable group.

Open access

Pilóta nélküli légi járművek alkalmazása a vizes élőhelyek modern felmérésében

Application of unmanned aerial vehicles as modern tools for wetland monitoring

Agrokémia és Talajtan
Authors:
Réka Döbröntey
,
János Grósz
,
Judit Rita Keleti
,
Tamás Szegi
,
Márta Fuchs
,
Erika Michéli
, and
Ádám Csorba

A vizes élőhelyek a vízi és a szárazföldi ökoszisztémák között elhelyezkedő, igen változatos, és általában nehezen lehatárolható területek. Kiemelt jelentőségük annak köszönhető, hogy bár csak a globális szárazföldi területek mintegy 6–7%-át borítják, kulcsfontosságú szerepet játszanak az éghajlat szabályozásában, a vizes ökoszisztémák biodiverzitásának és hidrológiai viszonyainak fenntartásában, valamint számos további ökológiai és társadalmi funkciót is szolgáltatnak, beleértve az árvízvédelmi, víztisztítási, szén-dioxid-tárolási, élőhelytámogatási és kulturális, rekreációs előnyöket. A vizes élőhelyek azonban mind természetes, mind antropogén hatások következtében térben és időben is dinamikusan változnak, ezért védelmük és megfigyelésük napjainkra igen fontos kutatási területté nőtte ki magát. A műholdas távérzékelés nagyobb területek egyidejű megfigyelését teszi lehetővé, azonban érzékeny a felhőzetre és a légköri hatásokra, bizonytalanságot okozva ezzel az eredményekben. A hagyományos monitoring technológiák mellett a pilóta nélküli légi járművek térnyerése egyre kifejezettebb, köszönhetően rugalmasságának, hatékonyságának és alacsony költségének, miközben nagy térbeli és időbeli felbontású, szisztematikus adatszolgáltatásra képes. Tanulmányunk a pilóta nélküli légi járművek alkalmazási lehetőségeibe nyújt betekintést a vizes élőhelyek felmérésében, valamint áttekinti és összehasonlítja az egyéb távérzékelés technológiák alkalmazhatóságát ezen területek megfigyelésében. Célja, hogy elősegítse a dróntechnológia további terjedését és széles körű alkalmazását a vizes élőhelyek monitorozásában.

Open access

Abstract

In this work, an assessment of effective solvents and extraction methods was carried out to recover the bioactive compounds from hawthorn fruit (Crataegus monogyna Jacq.). Extractions assisted by heat, microwave, and ultrasound were carried out using various organic solvents (methanol, ethanol, and isopropanol). pH differential, Folin–Ciocalteu's, and aluminum chloride methods were used to determine total monomeric anthocyanin (TMA), total phenolic compound (TPC), and total flavonoid content (TFC), consecutively. Ferric Reducing Antioxidant Power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl Hydrate (DPPH), and 2,2′- azino- bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assays were used to measure the antioxidant activity (AA) of the extracts. The outputs revealed that extraction methods and solvents significantly affect anthocyanin concentration, TPC, TFC, AA, and color values of hawthorn fruit extracts. Due to the highest recovered TMA (0.152 ± 0.002 mg ECy3Gl/g of dry weight), TPC (49.14 ± 0.38 mg gallic acid equivalents/g of dry weight), and TFC (18.38 ± 0.19 mg quercetin equivalents/g of dry weight) contents, the ultrasonic-assisted extraction is superior to heat and microwave-assisted extractions. Accordingly, it was also observed that the methanol solvent is more profound than ethanol and isopropanol. Further, the bioactive compounds' content and the extracts' antioxidant activity are shown to be highly correlated. Thus, hawthorn extracts are considered to have antioxidant properties because of their concentrated bioactive compounds.

Open access
Acta Alimentaria
Authors:
V. László
,
D. Szakos
,
V. Csizmadiáné Czuppon
, and
Gy. Kasza

Abstract

Consumer trust is essential to any market but particularly relevant to the food sector. Sustainable food systems require integration of small-scale food producers, for them consumer trust is pivotal. However, comprehensive measurement of consumer trust regarding local food is a less explored area. Based on the adjusted version of Benson's trust toolkit, local food trust was measured on four levels. This approach, connecting locality/proximity to food-related trust, was tested with a representative quantitative consumer survey (n = 1,001) in Hungary. Interpersonal trust, general organisation trust, local food chain trust, and local food product trust were measured on a 5-point Likert scale. Correlation and boxplot analysis conducted revealed that trust levels correlate significantly but remain independent from demographic characteristics, indicating that trust in local food is not region-, education-, or income-specific amongst Hungarian consumers. A relatively high level of consumer trust was measured for local food products and producers compared to other stakeholders, strengthening the assumption for the proximity-trust relationship regarding food. This is a key factor for small-scale food producers: only shared values with the local community and earned trust can attract customers despite less flexibility with pricing and limited capacity for advertising.

Open access