Zsolt Ajtony

6507774301

Publications - 21

Comparison of ultrasound-assisted extraction and modified QuEChERS technique for extraction of hesperidin from lemon peel (Citrus limon L.) as determined by HPLC

E. Lakatos Székelyhidi Rita Beatrix Sik Laura Végh Zsolt Ajtony

Publication Name: Journal of Food Composition and Analysis

Publication Date: 2025-06-01

Volume: 142

Issue: Unknown

Page Range: Unknown

Description:

Hesperidin (HSP) is a bioflavonoid known for its notable health benefits. Recent extraction strategies have aimed to minimize hazardous solvent use and simplify procedures to improve cost-effectiveness. This study compares ultrasound-assisted extraction (UAE) with a modified “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) method for the recovery of HSP. High-performance liquid chromatography with diode array detection (HPLC-DAD) was used for quantification. The modified QuEChERS method resulted in the highest extraction efficiency while significantly reducing processing time. The validated method demonstrated excellent sensitivity (LOQ: 10.0 µg/mL), high accuracy (recovery >93 %), and good precision (RSD <3.4 %), making it a reliable and cost-effective approach for routine HSP analysis in citrus peel. These findings indicate that the modified QuEChERS technique offers a promising alternative to UAE for the rapid and efficient extraction of HSP.

Open Access: Yes

DOI: 10.1016/j.jfca.2025.107553

Using natural deep eutectic solvents for the extraction of antioxidant compounds from cornelian cherry (Cornus mas L.) fruits

E. Lakatos Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Green Analytical Chemistry

Publication Date: 2024-12-01

Volume: 11

Issue: Unknown

Page Range: Unknown

Description:

Traditionally used extraction methods are usually based on toxic and/or flammable solvents. Therefore, currently, increased attention has been focused on environmentally friendly green extraction techniques. We aimed to develop a green extraction procedure by using natural deep eutectic solvents (NADES) to recover antioxidant compounds from cornelian cherry fruits (Cornus mas L.). Natural deep eutectic systems combined with maceration with shaking extraction were tested to recover of antioxidant compounds from cornelian cherry fruits. In this study, four different independent variables, namely solvent type (Glu-CA; Glu-Gly; LA-Glu), water concentration (30, 50, and 70 %; v/v), extraction time (30, 60, 90, and 120 min), and extraction temperature (25, 40, and 50 °C) were investigated. Glucose-glycerin (Glu-Gly; 1:1 M ratio) based solvent provided the best results. In addition, one-factor-at-a-time (OFAT) optimization showed that a temperature of 25 °C, 120 min of extraction time, and water concentration of 50 % (v/v) to be the best extraction parameters for Glu-Gly based NADES extraction. The developed method has been successfully applied for the extraction of antioxidant compounds from 13 different cornelian cherry cultivars. NADES can be used safely to extract phenolic compounds from cornelian cherry fruits compared to conventional extraction solvents (water and 80 % (v/v) ethanol).

Open Access: Yes

DOI: 10.1016/j.greeac.2024.100154

Valorization of Pea Pod (Pisum sativum L.) Waste: Application as a Functional Ingredient in Flatbreads

E. Lakatos Székelyhidi Rita Beatrix Sik G. Takács Zsolt Ajtony

Publication Name: Legume Science

Publication Date: 2024-12-01

Volume: 6

Issue: 4

Page Range: Unknown

Description:

Legumes provide valuable functional properties, serving as rich sources of protein, minerals, dietary fiber, and antioxidant compounds. This study evaluated the nutritional and antioxidant properties of pea pod powder (PPP) as a fortifying ingredient in flatbreads. The results indicate that PPP contains carbohydrates (55%), protein (16.7%), and dietary fiber (13.1%), with significant antioxidant properties (total polyphenol content: 463 mg GAE/100 g, total flavonoid content: 159 mg QE/100 g, DPPH radical scavenging activity: 166 mg AAE/100 g; IC50: 2.31 mg/mL, chlorophyll a: 17.4 mg/100 g, chlorophyll b: 17.4 mg/100 g, and total chlorophyll: 32.6 mg/100 g). Rutin, chlorogenic acid, and p-coumaric acid were identified and quantified by HPLC-DAD, with concentrations of 15.2, 2.94, and 6.60 mg/100 g, respectively. Flatbreads fortified with PPP at 5%w/w and 10%w/w showed increased thickness, reduced diameter and spread ratio, and enhanced antioxidant properties. However, consumer acceptance significantly declined at the 10%w/w level, likely due to off-flavors that affected sensory appeal.

Open Access: Yes

DOI: 10.1002/leg3.70017

Application of atomic spectroscopy for trace element analysis of fruit juices: a review

Pavithra Hemachandra Zsolt Ajtony László Bencs

Publication Name: Bio Web of Conferences

Publication Date: 2024-08-23

Volume: 125

Issue: Unknown

Page Range: Unknown

Description:

Trace elements are crucial for human nutrition, requiring their precise analysis in fruit juices to ensure product quality and assess contamination risks. Atomic spectroscopy techniques including inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma optical emission spectrometry (ICP-OES), graphite furnace atomic absorption spectrometry (GFAAS), flame atomic absorption spectrometry (FAAS), atomic fluorescence spectrometry (AFS), X-ray fluorescence spectrometry (XRF), and glow discharge optical emission spectrometry (GD-OES) are sensitive, selective and versatile tools for trace element analysis of various solid and solution samples. Matrix modifiers, sample introduction and sample preparation methods are pivotal for improving the accuracy and mitigating matrix interferences. Further advancements in instrumentation are essential. This review provides a comprehensive overview of these techniques, highlighting their principles, advantages, limitations and future research directions in fruit juice analysis. Its global applications, focusing on As, Cd, Co, and Pb, along with sample preparation methods, element concentrations, detection limits, and recovery values, have been explored.

Open Access: Yes

DOI: 10.1051/bioconf/202412502003

Citrus flavonoids (naringin and hesperidin) as functional ingredients in dairy products

Beatrix Sik U. R. Chandimala Zsolt Ajtony

Publication Name: Bio Web of Conferences

Publication Date: 2024-08-23

Volume: 125

Issue: Unknown

Page Range: Unknown

Description:

Recently, the development of functional foods enriched with plant phenolic compounds attracted the attention of researchers due to their favorable health properties. Naringin (NAR) and hesperidin (HES) are two main bioflavonoids available in high concentrations in citrus (CTS) fruits, including juice processing by-products like peel, membranes, and seeds. In general, NAR and HES offer potential health benefits in various diseases including diabetes mellitus, certain types of cancer, and obesity. However, to take advantage of the benefits of flavonoids in CTS, researchers must consider various factors since the development of enriched food is valueless if the bioactive compounds are not stable in the food matrix or are not absorbed appropriately throughout the digestive system. This study presents the sensory, physicochemical, and organoleptic properties of CTS-enriched dairy products produced by different technologies. This paper also includes the extraction methods, encapsulation technologies, and beneficial effects of NAR and HES. Overall, results supported that incorporating HES and NAR improves the antioxidant properties and, in some cases, the consumer acceptance of dairy products. In the future, the application of encapsulation technologies will probably come to the fore in the functional food industry, since encapsulation is used to mask unpleasant feelings during eating, such as the bitter taste of CTS flavonoids.

Open Access: Yes

DOI: 10.1051/bioconf/202412502004

Evaluation of the physical, antioxidant, and organoleptic properties of biscuits fortified with edible flower powders

E. Lakatos Székelyhidi Rita Beatrix Sik Laura Hanna Gál Zsolt Ajtony

Publication Name: Food Science and Nutrition

Publication Date: 2024-05-01

Volume: 12

Issue: 5

Page Range: 3265-3272

Description:

Foods enriched with plants have gradually become an area of increasing research interest because plant ingredients may offer several positive effects on human health and the body. The aim of our study was to develop biscuits fortified with three different types of edible flowers (marigold, lavender, and rose) and examine their physical and antioxidant characteristics, as well as consumer acceptability. The antioxidant properties and characterization of biscuits highlighted that edible flowers may cause increased total polyphenol and total flavonoid yields, as well as DPPH radical scavenging activities. Concerning biscuits fortified with rose petals, the total monomer anthocyanin content was also raised. In addition, the results showed that the antioxidant properties of biscuits increased with increasing concentration (from 2.5% to 5.0%) of edible flowers. Despite this, the consumer acceptability results clearly showed that the addition of marigold and lavender at a concentration of 5.0% caused significantly decreased overall acceptance. We found that the fortification step may increase the spread ratio, which is an important quality attribute of biscuits. We found slight variations in the diameter, thickness, and baking loss parameters of fortified biscuits compared to the control. All in all, the best results were obtained when the biscuits were fortified with rose petals at a concentration of 5%.

Open Access: Yes

DOI: 10.1002/fsn3.3993

Wild Blackberry Fruit (Rubus fruticosus L.) as Potential Functional Ingredient in Food: Ultrasound-Assisted Extraction Optimization, Ripening Period Evaluation, Application in Muffin, and Consumer Acceptance

E. Lakatos Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Foods

Publication Date: 2024-03-01

Volume: 13

Issue: 5

Page Range: Unknown

Description:

The aim of the present study is to evaluate the antioxidant properties of wild blackberry fruits as well as their possible use in powdered form as a functional ingredient. For this, ultrasound-assisted extraction optimization, ripening stage evaluation, and wild blackberry powder incorporation into a real food matrix were applied. The optimum conditions for extraction were as follows: 60% MeOH, 20 min of extraction time, acidification with 0.5% HCl, and a 1:40 g/mL solid-to-solvent ratio, which allowed the following yields: total polyphenol content (TPC): 53.8 mg GAE/g; total flavonoid content (TFC): 5.78 mg QE/g; total monomer anthocyanin content (TMA): 11.2 mg CGE/g; 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH): 71.5 mg AAE/g; IC50: 52.3 µg/mL. The study also highlighted that, during the ripening process, the TPC (41.4%), TFC (17.0%), and DPPH levels (66.4%) of the fruits decreased while the TMA yield increased. The incorporation of blackberry powder at different levels (5–20%) increased the TPC, TFC, TMA, and antioxidant properties of muffins. Although the muffins enriched with 20% wild blackberry powder had the best chemical properties (TPC: 3.15 mg GAE/g; TFC: 0.52 mg QE/g; TMA: 0.23 mg CGE/g; DPPH: 1.70 mg AAE/g; IC50: 1.65 mg/mL), the sensory analysis showed that the addition of blackberry fruit at a concentration of 10% to the muffins resulted in the best consumer acceptability.

Open Access: Yes

DOI: 10.3390/foods13050666

Measurement of Naringin from Citrus Fruits by High-Performance Liquid Chromatography–a Review

Beatrix Sik Aron Csuti Zsolt Ajtony

Publication Name: Critical Reviews in Analytical Chemistry

Publication Date: 2024-01-01

Volume: 54

Issue: 3

Page Range: 473-486

Description:

Naringin is a flavonoid found primarily in citrus species with especially high concentrations being present in grapefruit (Citrus paradisi), bitter orange (Citrus aurantium), and pomelo (Citrus grandis). Because of its many positive effects on human health, naringin has been the focus of increasing attention in recent years. Recently, conventional extraction methods have been commonly replaced with unconventional methods, such as ultrasound-assisted extraction (UAE) and other, more eco-friendly extraction methods requiring little-to-no environmentally harmful solvents or significantly less energy. Naringin analysis is most commonly done via high-performance liquid chromatography (HPLC), and ultrahigh-performance liquid chromatography (UHPLC) coupled with a mass spectrometer (MS) or a photodiode array (DAD) detector. The aim of this review is to provide an overview of recent trends developments in the extraction, sample preparation, and liquid chromatographic analysis of the compound originating from citrus fruits or their products.

Open Access: Yes

DOI: 10.1080/10408347.2022.2082241

Optimization and validation of HPLC–DAD method for simultaneous analysis of sweeteners, preservatives, and caffeine in sugar-free beverages

E. Lakatos Székelyhidi Rita Beatrix Sik Olivér Hegyi Zsolt Ajtony

Publication Name: European Food Research and Technology

Publication Date: 2023-11-01

Volume: 249

Issue: 11

Page Range: 2797-2805

Description:

In this study, the optimization and performance evaluation of a high-performance liquid chromatography with diode array detection (HPLC–DAD) method for the simultaneous determination of four sweeteners (acesulfame-potassium, saccharin, aspartame, and rebaudioside A), two preservatives (sodium benzoate and potassium sorbate), and caffeine in sugar-free drinks are presented. The separation was carried out using a gradient elution of acetonitrile and phosphate buffer (12.5 mM, pH = 3.3) on a reversed-phase column. Under the optimized conditions, the method allowed for the specific and selective simultaneous separation of all target analytes in less than 9 min. The developed HPLC–DAD method was validated and demonstrated excellent linearity (all analytical curves showed R2 ≥ 0.9995), satisfactory accuracy (recovery values ranging between 94.1 and 99.2% in real samples), and repeatability (intra- and inter-day relative standard deviations were ≤ 2.49%). Overall, 69 products available in the Hungarian market were successfully tested with the applied method.

Open Access: Yes

DOI: 10.1007/s00217-023-04328-4

Examining the Naringin Content and Sensory Characteristics of Functional Chocolate Fortified with Grapefruit Peel Extract

Beatrix Sik Aron Csuti Zsolt Ajtony

Publication Name: Plant Foods for Human Nutrition

Publication Date: 2023-09-01

Volume: 78

Issue: 3

Page Range: 533-538

Description:

Grapefruit peel contains a high concentration of naringin- a potent antioxidant with strong bioactive properties. In this study, a new type of functional chocolate fortified with grapefruit peel extract and different concentrations of aqueous methanol and ethanol were evaluated as extraction solvents. A new high-performance liquid chromatography (HPLC) method to analyze the naringin content of the fortified chocolates was developed with a recovery of 107% ± 3.1% and repeatability below 3.5%. A sensory evaluation was conducted to assess the preference for the chocolates among individuals who self-described a preference for bitter flavors. No significant preference was observed in the cases of astringency and aftertaste while the increased bitterness proved to be favorable. However, taste, flavor and overall acceptability were regarded somewhat less favorably. While chocolate proved to be a satisfactory carrier for naringin and had several enjoyable characteristics, further research may focus on improving the organoleptic properties of chocolates fortified by naringin.

Open Access: Yes

DOI: 10.1007/s11130-023-01091-5

The effects of extraction conditions on the antioxidant activities, total polyphenol and monomer anthocyanin contents of six edible fruits growing wild in Hungary

E. Lakatos Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Heliyon

Publication Date: 2022-12-01

Volume: 8

Issue: 12

Page Range: Unknown

Description:

Although wild fruits are significantly underutilized in most countries, they could be good sources of valuable bioactive compounds with antioxidant properties. Therefore the present study focused on the study of a conventional extraction technique (maceration with shaking; MACS) to extract natural antioxidants and anthocyanin colorants from six edible wild-growing fruits (European crab apple, bilberry, yellow-, red-, and purple-skinned greengage, and quince). One-factor-at-a-time (OFAT) methodology was chosen to investigate the influences of three different parameters (solvent type, extraction time and solvent acidity) on the total polyphenol contents (TPCs), total monomeric anthocyanin (TMA) contents, and antioxidant capacities, specifically ferric reducing power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity (DPPH). After optimization, the recorded TPCs and antioxidant activities proved to be significantly higher for all analyzed fruits when compared to differing extraction conditions. For European crab apple and purple-skinned greengage, the best extraction conditions were a ratio of 80:20 (v/v) EtOH–H2O, 1% (v/v) of HCOOH, and an extraction time of 90 min. In the case of red-skinned greengage, the extraction parameters were the same as the above except for the acid concentration (0.5%; v/v) used. For quince, the optimized conditions required a 50:50 (v/v) EtOH–H2O mixture, an extraction time of 90 min, and 0.5% (v/v) HCOOH concentration. The best conditions for the extraction of bilberry and yellow-skinned greengage were an EtOH–H2O combination of 50:50 (v/v), extraction time of 60 min, and HCOOH concentration of 0.5% (v/v). The highest TPC and antioxidant activity were observed in quince (281–510 mg GAE/100g and 109–395 mg AAE/100g) whereas the lowest were measured in European crab apple (55.9–70.0 mg GAE/100g and 20.1–43.2 mg AAE/100g). Bilberry exhibited the highest TMA content (346 mg CGE/100g). Overall, our results showed that these wild fruits could be a good source of natural antioxidants for the local residents.

Open Access: Yes

DOI: 10.1016/j.heliyon.2022.e12048

Analytical procedures for determination of phenolics active herbal ingredients in fortified functional foods: an overview

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: European Food Research and Technology

Publication Date: 2022-02-01

Volume: 248

Issue: 2

Page Range: 329-344

Description:

Fortification of foods with phenolic compounds is becoming increasingly popular due to their beneficial physiological effects. The biological activities reported include antioxidant, anticancer, antidiabetic, anti-inflammatory, or neuroprotective effects. However, the analysis of polyphenols in functional food matrices is a difficult task because of the complexity of the matrix. The main challenge is that polyphenols can interact with other food components, such as carbohydrates, proteins, or lipids. The chemical reactions that occur during the baking technologies in the bakery and biscuit industry may also affect the results of measurements. The analysis of polyphenols found in fortified foods can be done by several techniques, such as liquid chromatography (HPLC and UPLC), gas chromatography (GC), or spectrophotometry (TPC, DPPH, FRAP assay etc.). This paper aims to review the available information on analytical methods to fortified foodstuffs while as presenting the advantages and limitations of each technique.

Open Access: Yes

DOI: 10.1007/s00217-021-03908-6

Development of New HS–SPME–GC–MS Technique to the Measurement of Volatile Terpenoid Profile of Milk

E. Lakatos Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Food Analytical Methods

Publication Date: 2021-12-01

Volume: 14

Issue: 12

Page Range: 2585-2596

Description:

This study presented the development of such a HS–SPME–GC–MS technique, with the use of which, directly from the raw milk sample matrix, both qualitatively and quantitatively; the volatile terpenoids (α-pinene, sabinene, β-pinene, p-cymene, limonene, linalool, α-thujene, camphor, menthol, methyl chavicol, caryophyllene E, α-humulene) can be determined, derived from herbs eaten by the dairy animals by different feeding methods. Repeatability was less than 10% in the case of milk fat samples. The estimated limits of quantitation were between 2 and 16 ng/g. The lowest values were 2 ng/g for p-cymene and methyl chavicol; the highest value was 16 ng/g for caryophyllene. In the case of goat milk, the repeatability was better than 8% except for α-thujene. The estimated limits of quantitation were between 1 and 8 ng/g. The lowest values were 1 ng/g for β-pinene, p-cymene and limonene, and the highest value was 8 ng/g for linalool. In milk fat, the highest concentration was identified in caryophyllene E (470 ng/g) and α-humulene (430 ng/g), while the lowest concentration was in p-cymene (2 ng/g) and camphor (2 ng/g). In goat milk, limonene was present in all samples, but its amount varied depending on the type of consumed herb. Methyl chavicol and caryophyllene E were detected in goat’s milk only in one case. The former was detected in sage milk at 2.09 ng/g and the latter in tarragon milk at 2.28 ng/g. We have also successfully demonstrated that the feed consumed by dairy animals also affects the quality of dairy products.

Open Access: Yes

DOI: 10.1007/s12161-021-02070-9

Investigation of the long-term stability of various tinctures belonging to the lamiaceae family by HPLC and spectrophotometry method

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Chemical Papers

Publication Date: 2021-11-01

Volume: 75

Issue: 11

Page Range: 5781-5791

Description:

The aim of the current study was to analyze the stability of rosmarinic acid in ethanolic tinctures of lemon balm (Melissa officinalis L.), oregano (Origanum vulgare L.), peppermint (Mentha x piperita), rosemary (Rosmarinus officinalis L.), sage (Salvia officinalis L.), and thyme (Thymus vulgaris L.). High-performance liquid chromatography with diode-array detection (HPLC–DAD) was employed to monitor the concentration of the marker compound over a six month period. Furthermore, the tinctures were also evaluated for caffeic acid, total phenolic content, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. We observed that the concentration of rosmarinic acid in tincture stored in closed amber glasses at ambient temperature decreased significantly during 6-month storage. Furthermore, our study squarely confirms the fact that a part of rosmarinic acid is converted to caffeic acid. The tested tinctures can be listed in the following order according to the greatest stability of the marker compound: rosemary > peppermint > oregano > lemon balm > thyme > sage. The results of the study indicated a linear relationship between DPPH values and total phenolic (R2 = 0.92) or rosmarinic acid (R2 = 0.85) contents.

Open Access: Yes

DOI: 10.1007/s11696-021-01755-z

Exploring the rosmarinic acid profile of dark chocolate fortified with freeze-dried lemon balm extract using conventional and non-conventional extraction techniques

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Lwt

Publication Date: 2021-07-01

Volume: 147

Issue: Unknown

Page Range: Unknown

Description:

The present study evaluated the feasibility of the fortification of dark chocolate with a freeze-dried lemon balm extract rich in rosmarinic acid (RA). Given the food matrix used, it was necessary to develop an analytical and extraction method for RA determination in fortified chocolate. A simple and efficient reversed-phase high-performance liquid chromatography method (RP-HPLC) has been developed for the estimation of RA in dark chocolate. The validity of the method was demonstrated by evaluating the system suitability, linearity, precision, accuracy, the limit of detection, and limit of quantification. The extraction of RA from chocolate was optimized using maceration with shaking (MACS) and microwave-assisted extraction (MAE). The experimental conditions, namely solvent type and extraction time, were optimized using the one-factor-at-a-time methodology. Under the optimized conditions, the proposed method showed good recovery within 95% and acceptable reproducibility with intra- and inter-day relative standard deviations of <2.3%. The method was linear from 5 to 800 μg/mL with a determination coefficient of 1.000. Moreover, the functional chocolate showed a homogeneous active ingredient distribution and retained its RA amount since no significant difference was observed during storage. Overall, the present method was successfully applied to determine RA content in fortified chocolate.

Open Access: Yes

DOI: 10.1016/j.lwt.2021.111520

Application of the spme technique for determinate the quality indicators of dairy products

E. Lakatos Székelyhidi Rita Zsolt Ajtony

Publication Name: Elelmiszervizsgalati Kozlemenyek

Publication Date: 2020-12-01

Volume: 66

Issue: 4

Page Range: 3188-3201

Description:

Solid Phase Microextraction (SPME) is a relatively new extraction technique that combines taking samples from a mixture with a simpler desorption of the components to be analyzed of the unenriched sample in its original state in the analytical instrument. Based on a large number of publications in the literature, the authors describe the possibilities of using the SPME technique in the case of dairy products. The main groups of components that can be detected by the SPME sampling procedure, such as fatty acids, aldehydes and ketones, esters, alcohols, sulfur-containing organic compounds, furans, phenols and terpenoids are presented, through examples in the literature. Due to the limited scope of the manuscript, the authors report only on the possibilities of sample preparation using the SPME technique. Instrumental analytical methods following solid state microextraction, mainly using gas or liquid chromatography, are not described. Details of instrumental analyses are available in the cited literature sources.

Open Access: Yes

DOI: DOI not available

Conventional and nonconventional extraction techniques for optimal extraction processes of rosmarinic acid from six Lamiaceae plants as determined by HPLC-DAD measurement

E. Lakatos V. Kapcsándi Beatrix Sik Zsolt Ajtony

Publication Name: Journal of Pharmaceutical and Biomedical Analysis

Publication Date: 2020-05-30

Volume: 184

Issue: Unknown

Page Range: Unknown

Description:

The goal of this study was to improve the extraction efficiency of rosmarinic acid (RA) from Lamiaceae herbs (lemon balm, peppermint, oregano, rosemary, sage, and thyme) using various extraction techniques (maceration with stirring, MACS; heat reflux, HRE; and microwave-assisted extraction, MAE) and extraction conditions (solvent acidity, solvent type, extraction time and temperature). The RA content was measured by high-performance liquid chromatography with diode-array detection (HPLC-DAD) under test conditions. Our results showed that extraction with acidified aqueous ethanol (EtOH-H2O-HCl, 70:29:1, v/v/v) was the best choice for the recovery of RA compared to other solvent systems. Further study suggested the following optimal extraction times for the different techniques: 120 min at 25 °C with MACS, 15 min at boiling point with HRE, and 5 min at 50 °C and 80 °C with MAE. Based on our results, we demonstrated that by careful adjustment of the extraction conditions, it is possible to set up a single extraction protocol to extract RA from different plants.

Open Access: Yes

DOI: 10.1016/j.jpba.2020.113173

Recent advances in the analysis of rosmarinic acid from herbs in the lamiaceae family

E. Lakatos V. Kapcsándi Székelyhidi Rita Beatrix Sik Zsolt Ajtony

Publication Name: Natural Product Communications

Publication Date: 2019-01-01

Volume: 14

Issue: 7

Page Range: Unknown

Description:

Rosmarinic acid (RA) is a phenolic acid found in a variety of plants, especially those in the Lamiaceae family. A number of biological effects are attributed to the compound; so, in recent years, RA has been the focus of many studies. The aim of this review is to provide information on the latest developments on flow chromatography analysis of RA. A reverse-phase high-performance liquid chromatography (HPLC) method with gradient elution and either diode array or mass spectrometric detection is usually used to measure the compound. Factors affecting the performance of HPLC analysis of RA such as sample preparation, column, mobile phase, and detection methods are discussed in detail in this review.

Open Access: Yes

DOI: 10.1177/1934578X19864216

Application of laser-based photoacoustic spectroscopy and colorimetry for quantification of anthocyanin in hard boiled candy

Mihály Kovács Zsolt Ajtony Ottó Dóka Dane Bicanic

Publication Name: Microchemical Journal

Publication Date: 2017-11-01

Volume: 135

Issue: Unknown

Page Range: 100-104

Description:

The analytical performance of the newly proposed laser-based photoacoustic spectroscopy (LPAS) and colorimetric method for quantification of anthocyanin (E163) in commercially available hard boiled candies are compared to that of the spectrophotometry (SP). Both LPAS and colorimetry are direct methods that unlike SP do not require the extraction of the analyte or some additional sample treatment. Results indicate that LPAS and colorimetry are both suitable for quickly screening content of anthocyanin in hard boiled candies. The correlation between the two methods and spectrophotometry is linear with R2 = 0.9989 for LPAS and R2 = 0.9570 for colorimetry.

Open Access: Yes

DOI: 10.1016/j.microc.2017.08.013

Fast and direct screening of copper in micro-volumes of distilled alcoholic beverages by high-resolution continuum source graphite furnace atomic absorption spectrometry

Gabriella Dravecz Nikoletta Laczai Áron Marosi Bence Marlok Norbert Szoboszlai Zsolt Ajtony László Bencs Christina Streli

Publication Name: Food Chemistry

Publication Date: 2016-12-15

Volume: 213

Issue: Unknown

Page Range: 799-805

Description:

HR-CS-GFAAS methods were developed for the fast determination of Cu in domestic and commercially available Hungarian distilled alcoholic beverages (called pálinka), in order to decide if their Cu content exceeds the permissible limit, as legislated by the WHO. Some microliters of samples were directly dispensed into the atomizer. Graphite furnace heating programs, effects/amounts of the Pd modifier, alternative wavelengths (e.g., Cu I 249.2146 nm), external calibration and internal standardization methods were studied. Applying a fast graphite furnace heating program without any chemical modifier, the Cu content of a sample could be quantitated within 1.5 min. The detection limit of the method is 0.03 mg/L. Calibration curves are linear up to 10–15 mg/L Cu. Spike-recoveries ranged from 89% to 119% with an average of 100.9 ± 8.5%. Internal calibration could be applied with the assistance of Cr, Fe, and/or Rh standards. The accuracy of the GFAAS results was verified by TXRF analyses.

Open Access: Yes

DOI: 10.1016/j.foodchem.2016.06.090

Application of chlorogenic acid in dairy product enrichment/fortification – a review

U. R. Chandimala Zsolt Ajtony

Publication Name: Lwt

Publication Date: 2025-09-15

Volume: 232

Issue: Unknown

Page Range: Unknown

Description:

Chlorogenic acid (CGA), also known as 5-O-caffeoylquinic acid, is one of the most abundant phenolic compounds in nature. CGA exhibits antioxidant, anti-inflammatory, anti-tumor, neuroprotective, cardiovascular, hepatoprotective, and metabolic regulatory properties. Due to the high usage of milk and fermented milk products, dairy becomes an excellent food source for CGA fortification, focusing on exploiting health benefits for consumers. An increasing trend exists in utilizing plant materials rich in CGA in dairy formulations to enhance dairy products' antioxidant profile and health-promoting potential. This review examines 58 recent studies on CGA incorporation into dairy products, focusing on their chemistry, biological activities, processing methods, and potential challenges for fortification. Extraction techniques such as microwave-assisted extraction and ultrasonic-assisted methods are preferred over conventional methods due to their efficiency and the quality of the extracts. In dairy formulations, thermal processing, high-pressure homogenization, controlled fermentation, and encapsulation techniques are critical for maintaining the stability and efficacy of CGA. Encapsulation with materials like β-cyclodextrin and chitosan nanoparticles enhances CGA stability during processing, storage, and digestion. This review emphasizes the significance of understanding CGA-protein interactions in dairy matrices, as these can either protect CGA from degradation or influence its bioavailability. The findings of this study underscore, in heat-treated and fermented dairy systems, that processing-induced CGA-milk protein interactions safeguard CGA from oxidative damage and improve CGA's bioaccessibility. Further research is needed to optimize CGA fortification strategies in dairy products to maximize their functional benefits.

Open Access: Yes

DOI: 10.1016/j.lwt.2025.118416