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The current study focuses on evaluating the enzyme inhibition (acetylcholinesterase, α-amylase, α-glucosidase, pancreatin lipase), antioxidant, and antimicrobial activities of the “Modesto” apricot, “Stanley” plum, and their hybrid the “Stendesto” plum–apricot. The “Stendesto” is the only successful plum–apricot hybrid in Bulgaria. A spectrophotometric approach was used to evaluate the antioxidant activity following four complementary assays (DPPH, ABTS, FRAP, and CUPRAC). The “Stendesto” plum–apricot revealed its enhanced antioxidant potential compared to its parental lines. Apart from the free phenolics extraction, two other techniques (alkaline and acid hydrolysis) were applied to reveal the biological potential of the studied fruit. Not only free but also bound phenolic extracts were able to inhibit α-glucosidase and acetylcholinesterase, while none of the extracts inhibited lipase or α-amylase. None of the apricot extracts had antimicrobial activity, while the other fruit had limited antimicrobial activity. The proposed results undoubtedly reveal that hybrid fruits possess enhanced biological activity compared to their parents. This is a first comprehensive evaluation of hybrid fruits with reference to parental lines. This makes them an interesting research topic that should be better explored.

To comply with a more circular and environmentally friendly European common agricultural policy, while also valorising sunflower by-products, an ultrasound assisted extraction (UAE) was tested to optimise ethanol-wash solutes (EWS). Furthermore, the capabilities of DART-HRMS as a rapid and cost-effective tool for determining the biochemical changes after valorisation of these defatted sunflower EWS were investigated. Three batches of EWS were doubly processed into optimised EWS (OEWS) samples, which were analysed via DART-HRMS. Then, the metabolic profiles were submitted to a univariate analysis followed by a partial least square discriminant analysis (PLS-DA) allowing the identification of the 15 most informative ions. The assessment of the metabolomic fingerprinting characterising EWS and OEWS resulted in an accurate and well-defined spatial clusterization based on the retrieved pool of informative ions. The outcomes highlighted a significantly higher relative abundance of phenolipid hydroxycinnamoyl-glyceric acid and a lower incidence of free fatty acids and diglycerides due to the ultrasound treatment. These resulting biochemical changes might turn OEWS into a natural antioxidant supplement useful for controlling lipid oxidation and to prolong the shelf-life of foods and feeds. A standardised processing leading to a selective concentration of the desirable bioactive compounds is also advisable.

In this study, the ultrasonic extraction (UAE) of free phenolic compounds and relative biological activities of the Bulgarian peach variety “Filina” was optimized using chemometric techniques (response surface methodology). A Box–Behnken design was used to reveal the variation in the hydro module, temperature, duration, and extractant on the total phenolic content, total flavonoid content, antioxidant potential, and inhibitory activity on each yield. The results revealed that the optimal conditions included a hydro module of 20, a duration of 39.33 min, a temperature of 70 °C, and an extractant of 96.64% to retrieve the highest level of bioactive compounds. The calculated parameters were discovered to be following the projected values.

Contemporary living is continuously leading to poor everyday choices resulting in the manifestation of various diseases. The benefits of plant-based nutrition are undeniable and research on the topic is rising. Modern man is now aware of the possibilities that plant nutrition can provide and is seeking ways to benefit from it. Dietary phenolic compounds are among the easily accessible beneficial substances that can exhibit antioxidant, anti-inflammatory, antitumor, antibacterial, antiviral, antifungal, antiparasitic, analgesic, anti-diabetic, anti-atherogenic, antiproliferative, as well as cardio-and neuroprotective activities. Several industries are exploring ways to incorporate biologically active substances in their produce. This review is concentrated on presenting current information about the dietary phenolic compounds and their contribution to maintaining good health. Additionally, this content will demonstrate the importance and prosperity of natural compounds for various fields, i.e., food industry, cosmetology, and biotechnology, among others.

The “Stendesto” plumcot is the only successful Bulgarian plum–apricot hybrid having the “Modesto” apricot and the “Stanley” plum as parents. The current study reports on the metabolites and volatile organic compounds (VOCs) discovered in the three fruits. Forty-one metabolites in total, as represented by amino acids, organic acids, sugar acids and alcohols, phenolic acids, fatty acids, mono- and di-saccharides, and sterols, were identified in the samples. Additionally, sixty-five VOCs were profiled using the gas chromatography/mass spectrometry (GC/MS) analysis and HS-SPME technique. Among these VOCs, alcohols, aldehydes, esters, ketones, lactones, terpenoids, and benzene derivatives were the existing chemical classes. Not all metabolites were present in both apricot and plum, but the hybrid had managed to inherit all of the identified metabolites with the exception of γ-aminobutyric acid. This study is a first on the topic of plumcot fruit evaluation referencing its parental lines. Principal component (PCA) and hierarchical cluster (HCA) analyses further aided in revealing the differences and similarities between the “Stendesto” plum–apricot hybrid and its parents.

Plum–apricot hybrids are the successful backcrosses of plums and apricots. Plums and apricots are well-known and preferred by consumers because of their distinct sensory and beneficial health properties. However, kernel consumption remains limited even though kernels are easily accessible. The “Stendesto” hybrid originates from the “Modesto” apricot and the “Stanley” plum. Kernal metabolites exhibited quantitative differences in terms of metabolites identified by gas chromatography–mass spectrometry (GC–MS) analysis and HS-SPME technique profiling. The results revealed a total of 55 different compounds. Phenolic acids, hydrocarbons, organic acids, fatty acids, sugar acids and alcohols, mono- and disaccharides, as well as amino acids were identified in the studied kernels. The hybrid kernel generally inherited all the metabolites present in the parental kernels. Volatile organic compounds were also investigated. Thirty-five compounds identified as aldehydes, alcohols, ketones, furans, acids, esters, and alkanes were present in the studied samples. Considering volatile organic compounds (VOCs), the hybrid kernel had more resemblance to the plum one, bearing that alkanes were only identified in the apricot kernel. The objective of this study was to investigate the volatile composition and metabolic profile of the first Bulgarian plum–apricot hybrid kernels, and to provide comparable data relevant to both parents. With the aid of principal component analysis (PCA) and hierarchical cluster analysis (HCA), differentiation and clustering of the results occurred in terms of the metabolites present in the plum–apricot hybrid kernels with reference to their parental lines. This study is the first providing information about the metabolic profile of variety-defined kernels. It is also a pioneering study on the comprehensive evaluation of fruit hybrids.

Research background. There is an increasing interest in foods with added nutritional value. This study presents the opportunity for the reformulation of muffins using chia seeds and lyophilized peach powder in view of the emerging societal challenges regarding unhealthy eating patterns and food intolerances. Experimental approach. Two new formulations were developed to eliminate the use of eggs and alter the flour content and type. Physical characteristics, texture analysis, water activity, microbial load, antioxidant potential and sensory profile aided in the evaluation of the newly developed products. Results and conclusions. The results indicate an inversely proportional relationship between the relative mass of the dough and physical parameters (density, volume and height) of all muffin formulations. The modification of the original recipe compared to the control sample led to decreased baking losses, increased total phenolic content, as well as enhanced nutritional value in terms of fibre content. The addition of chia seeds and peach powder led to positive sensory changes. The alteration of the original recipe resulted in significant effect on the colour, making the muffins darker and less yellow than the control sample. In terms of texture characteristics, the new formulations had a profile close to the control. Novelty and scientific contribution. Recipe reformulation without deteriorating quality attributes is important for the food technology field. Reformulation should comply with the new expectations of the modern consumer. The study targets an approach where new products with enhanced functional characteristics are presented. §Paper was presented at the 11th Central European Congress on Food and Nutrition CEFood2022, Čatež ob Savi, Slovenia, 27-30 September 2022

Representatives of the Prunus genera, found in almost every country and continent, have been recognized not only for their delicious fruits and nuts, but also because of their beneficial properties. To date, numerous cultivars have been phytochemically studied, leading to the identification of various compounds including terpenes, tannins, flavonoids, phenolic acids, carotenoids, fatty acids, and so on. Pharmacological studies on Prunus species have also revealed a variety of bioactive potentials including antioxidant, anti-inflammatory, hypolipidemic, antidiabetic, brain protecting, and other evidence based uses. This review covers articles, retrieved from scientific databases, using “Prunus” as search term (“all fields”) and with a specific time frame set for search. Information about Prunus amygdalus, Prunus armeniaca, Prunus cerasifera, Prunus persica, Prunus domestica, Prunus avium, and Prunus cerasus was selected and summarized giving information about their ethnopharmacological uses, isolated phytochemicals, and pharmacological activities.

Phycocyanin is a pigment–protein complex from the group of phycobiliproteins obtained from Spirulina (Arthrospira platensis), with possibilities for various applications in food and pharmaceutical technologies. It is a natural colorant for food and cosmetic products. This study aimed to investigate the effect of ultrasonic and microwave extraction conditions on antioxidant activity (AOA), chlorophyll content, and the content and purity index of phycocyanin in aqueous and alcoholic extracts of Spirulina (Arthrospira platensis). For this purpose, ultrasonic extraction with water or ethanol was performed at 20 °C, 30 °C, and 40 °C for 1, 2, and 3 h at an ultrasonic frequency of 36 kHz, 40 kHz, and 45 kHz. Microwave water extraction was performed for 60 s, 120 s, and 180 s. For each of the obtained samples, three parallel measurements of antioxidant activity were made by DPPH and FRAP methods, and chlorophyll content and phycocyanin yield and purity index were determined spectrophotometrically. Ultrasonic extraction resulted in a higher yield and purity index of phycocyanin compared to microwave extraction. The highest yield of 14.88 mg g−1 with a purity index of 1.60 was achieved at a temperature of 40 °C for one hour and an ultrasonic wave frequency of 40 kHz. A relatively low yield of 4.21 mg g−1, but with a purity index of 2.67, was obtained at a temperature of 30 °C, a time of two hours, and an ultrasonic frequency of 40 kHz. Chlorophyll b content at 20 °C, for two hours and ultrasonic frequency 40 kHz was 1.400 mg g−1. The study proposes ultrasonic extraction as a green method to obtain phycocyanin of varying purity index that may be used for food, cosmetic, or biomedical purposes.

The emerging demand for everyday food substitutes is increasing on a daily basis. More and more individuals struggle with allergies and intolerances, which makes it mandatory to provide alternatives for simple products like dairy milk. Plant-based beverages (PBBs) are currently trending due to the multiple diets that promote their consumption with or without a justification. PBBs can derive from various types of plants, not exclusively nuts. Some of the most well-known sources are almonds, soy, rice, and hazelnuts, among others. In view of the need for sustainable approaches to resource utilization and food production, novel sources for PBBs are being sought, and those include fruit kernels. The plant kingdom offers a palette of resources with proven bioactivity, i.e., containing flavonoids, phenolic acids, vitamins, carotenoids, and phenolics, among others. Many of these beneficial substances are water soluble, which means they could be transferred to the plant beverage compositions. The current review aims at comparing the vast number of potential formulations based on their specific nutritional profiles and potential deficiencies, as well as their expected health-promoting properties, based on the raw material(s) used for production. Special attention will be given to the antinutrients, usually abundant in plant-based sources.

Bifidobacterium is a predominant and important genus in the bacterial population of the human gut microbiota. Despite the increasing number of studies on the beneficial functionality of bifidobacteria for human health, knowledge about their antioxidant potential is still insufficient. Several in vivo and in vitro studies of Bifidobacterium strains and their cellular components have shown good antioxidant capacity that provided a certain protection of their own and the host’s cells. Our work presents the data of transcriptomic, proteomic, and metabolomic analyses of the growing and stationary culture of the probiotic strain B. longum subsp. longum GT15 after exposure to hydrogen peroxide for 2 h and oxygen for 2 and 4 h. The results of the analysis of the sequenced genome of B. longum GT15 showed the presence of 16 gene-encoding proteins with known antioxidant functions. The results of the full transcriptomic analysis demonstrated a more than two-fold increase of levels of transcripts for eleven genes, encoding proteins with antioxidant functions. Proteomic data analysis showed an increased level of more than two times for glutaredoxin and thioredoxin after the exposure to oxygen, which indicates that the thioredoxin-dependent antioxidant system may be the major redox homeostasis system in B. longum bacteria. We also found that the levels of proteins presumably involved in global stress, amino acid metabolism, nucleotide and carbohydrate metabolism, and transport had significantly increased in response to oxidative stress. The metabolic fingerprint analysis also showed good discrimination between cells responding to oxidative stress and the untreated controls. Our results provide a greater understanding of the mechanism of oxidative stress response in B. longum and the factors that contribute to its survival in functional food products.

The present study was carried out to determine some physicochemical, composition and sensory attributes of early-ripening peach varieties: “Filina” (peach), “Gergana” (nectarine), and “Ufo-4” (flat peach). Fruit weight, shape and size, as well as color and firmness were evaluated. Image analysis was used to describe properties such as length, width, thickness, etc. Skin hue ranged from 33.45±10.70 to 42.75±29.87. Dry matter (%), ash content (%), total soluble solids, pH, titratable acidity, total sugar content, and protein content were employed to characterize the studied varieties. Results showed differences in all properties of the types. Ash content varied from 0.45±0.04% to 0.96±0.12% and pH from 3.95 to 4.46. “Gergana” had the lowest total soluble solids. A trained descriptive sensory panel evaluated the peach varieties in five categories with a total of twenty-five attributes. The fruit attributes were evaluated by a 15-point ascending scale. The panellists detected differences between varieties in each of the categories (aroma, texture, taste, internal and external appearance). These results offer and highlight new data in terms of early-ripening peach variety properties.A trained descriptive sensory panel evaluated the peach varieties in five categories with a total of twenty-five attributes. The fruit attributes were evaluated by a 15-point scale, in which 15 equals more of an attribute. The panelists detected differences between genotypes in each of the categories (aroma, texture, taste, internal and external appearance). These results offer and highlight new data in terms of early-ripening peach variety properties.

Plum–apricot hybrids are successful backcrosses of plums and apricots resulting in plumcots, pluots, and apriums. A topic search on plums, apricots, and plumcots shows that extensive information exists on the agro-morphology, genotyping, bioactive substances, and nutritive value of the genus Prunus, and plums and apricots, in particular. However, when search results for plum–apricot hybrids were evaluated for the period 2010–2023, only a few papers focused partially on the topic of their metabolomics. A database search (Scopus, PubMed, and Google Scholar) exposed that less than 10 articles/year appeared in Scopus on the topic of plum–apricot hybrids, 618 papers were found on Google Scholar (2010–2023), and only 2 results were found in PubMed for the same period using the same keywords. This shows the grand research opportunity and the need for providing a thorough chemical characterization of the existing plum–apricot hybrids. This review aims at schematizing the available information about plum–apricot hybrids (with reference to their parents), identifying the gaps about their bioactive compounds, antioxidant activities, and health beneficial properties, as well as pointing to future perspectives in terms of fruit hybrid characterization.

Chlorophylls are a group of naturally occurring pigments that are responsible for the green color in plants. This pigment group could have numerous health benefits due to its high antioxidant activity, including anti-inflammatory, anti-cancer, and anti-obesity properties. Many food by-products contain a high level of chlorophyll content. These by-products are discarded and considered environmental pollutants if not used as a source of bioactive compounds. The recovery of chlorophylls from food by-products is an interesting approach for increasing the sustainability of food production. This paper provides insight into the properties of chlorophylls and the effect of different treatments on their stability, and then reviews the latest research on the extraction of chlorophylls from a sustainable perspective.

In this research, the possibilities of applying the extrusion process to produce functional food from quinoa enriched with goji berries were studied. The physical (expansion ratio, bulk density, hardness, and specific mechanical energy) and functional (water solubility index, water absorption index) characteristics were determined and optimized by the response surface methodology. Extrudates were produced using a laboratory single-screw extruder. The full factorial experimental design was used (N = 22) with three complementary center points to show the interactions of the amount of goji berry (1, 3, and 5%) and the feed moisture content (13, 16, and 19%) of the mixture on the physical and functional characteristics. Increasing moisture content from 13 to 19% resulted in extrudates with a lower expansion ratio, water absorption index, water solubility index, specific mechanical energy, and higher density and hardness. Increasing the amount of goji berries from 1 to 5% led to a decrease in expansion ratio, water absorption index, and hardness, and an increase in density, water solubility index, and specific mechanical energy. Optimal extrusion conditions for production of extrudates from quinoa enriched with goji berry were 16.3% feed moisture content and 1.32% goji berry’s amount.

This work aimed to study the flux behavior, rejection and concentration factors, and energy demand to establish the optimal conditions during ultrafiltration of sweet buttermilk to produce ice cream. The experiments were conducted with a UF25-PAN membrane at a transmembrane pressure of 0.2, 0.35 and 0.5 MPa, and a volume reduction ratio (VRR) of 2, 3, 4, and 5. Total protein, fat, ash, and dry matter contents, phospholipid composition, and acidity of retentates and permeate were determined. The increase in the VRR led to a decrease in the permeate flux and an increase in the energy demand, rejection, and concentration factors of the main components of sweet buttermilk. The highest values of rejection and concentration factors established for fat were 98.65% and 4.93, respectively. The permeate flux and energy demand increased with the rise in the transmembrane pressure. The total phospholipids increased 2.8 times at VRR 5 compared to the initial buttermilk. The use of VRR 3 gave the best ratio between the permeate flux, the energy demand, and relatively high values of concentration and rejection factors. The use of VRR 5 will enrich the ice cream to the greatest extent to obtain a product with the highest level of biologically active substances (proteins, phospholipids, minerals).

Recently, there has been a considerable interest in finding natural antioxidants from plant materials to replace the synthetic ones. The edible flowers represent a valuable alternative source of bioactive compounds and have been used as food and herbs with increasing interest. The antioxidant properties of 7 edible flowers of the South Bulgaria, including Viola tricolor L., Cucurbita pepo L., Sambucus nigra L., Calendula officinalis L., Hibiscus rosa-sinensis L., Rosa damascena Mill., and Allium ursinum L. were evaluated. The contents of flower chemicals, such as total phenolics and total flavonoids content, were determined as well. By comparing decoction and infusion as methods of extraction, the decoction ones revealed to be the most appropriate in respect of the evaluated compounds. The results showed that the highest antioxidant activity was found in the Rosa damascena and Viola tricolor ones. The established total polyphenol content and total flavonoids in the decocts of Rosa damascena and Viola tricolor were 56.66 ± 0.48 and 135.82 ± 1.50 mg GAE/g dw and 28.60 ± 0.43 and 15.87± 0.52 mg QЕ/g dw, respectively. The present research extends the traditional knowledge and revealed an opportunity to obtain biological active substances of the nature and edible flowers in particular.

Beetroot, the cultivated form of Beta vulgaris subsp. vulgaris, is known for its various beneficial properties but more critical data about its bioactive compounds digestion is needed. In the present research, the bioaccessibility of phytochemicals in freshly prepared red beetroot juice was studied. Changes in total phenolics content, total flavonoids content, contents of betacyanins and betaxanthins, phenolic acids profile as well as the antioxidant activity were monitored before and after simulated gastrointestinal digestion. Several parameters that provide interrelated information about food quality were additionally evaluated, including oxalic acid and individual sugars content, total titratable acidity, and acetylcholinesterase inhibitory activity. Significant loss of contents of total phenolics and flavonoids measured after digestion resulted in the recovery of 27.07 and 36.4%, respectively. The same negative tendency was observed for betalains bioaccessibility. While nearly 27% of betaxanthins were present after the simulated digestion, almost all betacyanins (96.07%) have been lost. The HPLC analysis of phenolic acids of beetroot juice revealed the presence of chlorogenic, caffeic, p -coumaric, and sinapic acids. After digestion, a 2.5-fold higher concentration of chlorogenic acid was found, however caffeic and p-coumaric acids were no longer detected. The results concerning the antioxidant activity of digested juice were inexplicit. According to the DPPH assay, there was a complete recovery of antioxidant activity, while no activity was detected employing the ABTS assay. Following the cupric ion reducing antioxidant capacity (CUPRAC) and ferric-reducing antioxidant power (FRAP), approximately half of the initial activity was retained. Despite the losses, red beetroot remains a valuable source of biologically active substances. Better understanding of their transformation during digestion is further needed.

Enzymatic browning could negatively affect the sensory and nutritional properties of eggplants post-harvest. Polyphenols, polyphenol oxidase (PPO), and reactive oxygen species (ROS) are three material conditions involved in enzymatic browning. This paper seeks to evaluate the effect of fertilization techniques and grafting on the activity of PPO and colorimetric parameters in cultivated eggplants. Fertilization alone significantly increased the PPO activity in all eggplant fleshes (p ≤ 0.05), whereas the grafting technique combined with fertilization decreased the PPO activity in most of the samples significantly (p ≤ 0.05). Moreover, there was a significant positive correlation between the PPO activity and the a* values of the eggplants. The a* values in grafted eggplants were significantly different from each other (p ≤ 0.05), showing that grafting the fertilized eggplants could be effective in controlling the enzymatic browning. The eggplant slices exposed to air for 60 min at room temperature showed a significant increase (p ≤ 0.05) in PPO activity, browning index (BI), total color difference (ΔE), and a*, b*, and c* values. Thus, it is necessary to minimize the exposure time of the slices to air at room temperature, even if combining fertilization techniques with grafting could delay the enzymatic browning in fresh-cut eggplants.

The natural products of the plant kingdom, both terrestrial and marine, have been widely explored [...]

Sustainability, becoming essential for food processing and technology, sets goals for the characterization of resources considered as food waste. In this work, information about the GC-MS metabolites of peach peels was provided as a tool that can shed more light on the studied biological activities. In addition, distribution patterns and contribution of the chemical profile and free and bound phenolic compounds as antioxidant, antimicrobial, and enzymatic clusters in peach peels of different varieties of Bulgarian origin were studied. The two applied techniques (alkaline and acid hydrolysis) for releasing the bound phenolics reveal that alkaline hydrolysis is a better extraction approach. Still, the results indicate the prevalence of the free phenolics in the studied peach peel varieties. Total phenolics of peach wastes were positively correlated with their antioxidant activity. The antioxidant activity results certainly defined the need of an individual interpretation for each variety, but the free phenolics fractions could be outlined with the strongest potential. The limited ability of the peels’ extracts to inhibit α-amylase and acetylcholinesterase, and the moderate antimicrobial activity, on the other hand, indicate that the potential of peach peels is still sufficient to seek ways to valorize this waste. Indeed, this new information about peach peels can be used to characterize peach fruits from different countries and/or different food processes, as well as to promote the use of this fruit waste in food preparation.

Research on food-derived bioactive peptides is expanding and the need for a convenient online platform that combines a foolproof and intuitive user interface with a reliable database and tools for prediction and analysis is rising. In this regard, this paper presents an open-access web-based platform PepLab (Peptides Laboratory). The database contains 2764 peptide sequence entries, grouped into sixteen classes according to their biological activity and into seven classes according to the source from which they were derived. Moreover, it includes bioinformatic tools for their processing and analysis. The DMpep tool allows extracting information about a number of physicochemical characteristics of a peptide or a set of peptides, including those that are not recorded in the database. The main advantages of PepLab are a user-friendly interface, a responsive design, and optimized search engines for better visibility on the Internet. Prediction of non-reported activity is available based on amino acid sequence analysis. In addition, users can download data and results in a convenient format (text and/or graphic) that was limited in the existing platforms. In this way, the presented PepLab platform will be helpful for researchers from various fields—bioinformatics, pharmaceuticals, food sciences, dietetics, biotechnology, analytical chemistry, etc.

Higher basidiomycetes are recognized as functional foods due to their bioactive compound content, which exerts various beneficial effects on human health, and which have been used as sources for the development of natural medicines and nutraceuticals for centuries. The aim of this study was to evaluate and compare the biological potential of basidiocarp and mycelial biomass produced by submerged cultivation of a new regionally isolated oyster mushroom. The strain was identified with a high percentage of confidence (99.30%) as Pleurotus ostreatus and was deposited in the GenBank under accession number MW 996755. The β-glucan content in the basidiocarp and the obtained mycelial biomass was 31.66% and 12.04%, respectively. Three mycelial biomass and basidiocarp extracts were prepared, and the highest total polyphenol content (5.68 ± 0.15 mg GAE/g DW and 3.20 ± 0.04 mg GAE/g DW) was found in the water extract for both the fruiting body and the mycelium biomass. The in vitro antioxidant activity of the extracts was investigated, and it was determined that the water extracts exhibited the most potent radical scavenging activity. The potential ability of this new fungal isolate to affect the contractile activity (CA) of dissected smooth muscle preparations (SMP) was examined for the first time. It was found that oyster mushrooms likely exhibit indirect contractile effects on the gastric smooth muscle (SM) cells.

Dietary proteins are no longer just nutritional ingredients in our food. During hydrolysis, some of the released peptides may possess properties that favor the health of the human body. In our study enzymatic hydrolysis of lupin proteins was performed using papain. Three enzyme-to-substrate ratios were set for three different duration times. The SDS-PAGE of the samples was performed. Each hydrolysate was studied for the degree of hydrolysis (DH), acetylcholinesterase (AChE) inhibitory, antimicrobial, and antioxidant activities (AOA, according to four spectrophotometric methods). The DH varied from 9.06 ± 0.20 to 27.97 ± 0.37%. According to the results, the best AOA was measured by the ABTS method (from 0.76 ± 0.03 to 1.15 ± 0.46 M TE/100 g protein). All the hydrolysates displayed AChE inhibitory activity (IC50), which varied between 155.58 ± 1.87 and 199.63 ± 0.41 mg/g protein. To the best of our knowledge, this is the first report of the acetylcholinesterase inhibitory activity of lupin protein hydrolysates. In conclusion, lupin proteins prove to have a high potential to serve as a source of bioactive peptides.

A fruit’s aroma profile, composed of a complex mixture of volatile organic compounds, is among the core attributes related to the overall taste and consumer preference. Prunus persica L. is a preferred summer fruit with a distinct, favorable olfactory characteristic. The volatile compositions of both peach fruits and fruit pulps from eight peach cultivars (four native and four introduced) was investigated to compare their composition and assess flavor-contributing compounds. In total, 65 compounds were profiled after a HS-SPME-GC-MS analysis: 16 esters, 14 aldehydes, 5 alcohols, 7 hydrocarbons, 7 ketones, 8 acids, and 8 terpenes. The most common compounds were esters, acids, and aldehydes. Although the same compounds were identified in both fruit and pulp, their %TIC (total ion current) differed in favor of the whole fruit. Following the metabolic profiling of the whole fruit and fruit pulp, a total of 44 compounds were identified from the studied varieties. Among them, amino acids, organic acids, sugar alcohols, saccharides, fatty acids, and phenolic acids were identified as existing groups. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative %TIC of the identified volatile compounds fluctuated depending on the studied cultivar. No differences were visible in the PCA biplots, which suggested that the polar and lipid metabolites do not provide significant variations when considering different parts of the fruit, contrary to the volatile compounds. The obtained results could successfully be applied in the metabolic chemotaxonomy of peaches and the differentiation of the metabolites present in different parts of the peach.

To find the most optimal green valorization process of food by-products, sugar beet (Beta vulgaris L.) leaves (SBLs) were freeze-dried and ground with/without liquid nitrogen (LN), as a simple sample pretreatment method, before ultrasound-assisted extraction (UAE) of polyphenols. First, the water activity, proximate composition, amino acid (AA) and fatty acid (FA) profiles, and polyphenol oxidase (PPO) activity of dried and fresh SBLs were evaluated. Then, conventional extraction (CE) and UAE of polyphenols from SBLs using water/EtOH:water 14:6 (v/v) as extracting solvents were performed to determine the individual and combined effects of the sample preparation method and UAE. In all the freeze-dried samples, the specific activity of PPO decreased significantly (p ≤ 0.05). Freeze-drying significantly increased (p ≤ 0.05) the fiber and essential FA contents of SBLs. The FA profile of SBLs revealed that they are rich sources of oleic, linoleic, and α-linolenic acids. Although freeze-drying changed the contents of most AAs insignificantly, lysine increased significantly from 7.06 ± 0.46% to 8.32 ± 0.38%. The aqueous UAE of the freeze-dried samples without LN pretreatment yielded the most optimal total phenolic content (TPC) (69.44 ± 0.15 mg gallic acid equivalent/g dry matter (mg GAE/g DM)) and excellent antioxidant activities. Thus, combining freeze-drying with the aqueous UAE method could be proposed as a sustainable strategy for extracting bioactive compounds from food by-products.

Sorbets are healthy ice cream alternatives and desired frozen desserts by vegetarians and vegans. This study focuses on assessing the effects of sorbet recipe alteration through the addition of different percentages of Zizyphus jujuba powder. Stevia rebaudiana was used as a sugar substituent. A control sample and five variables were developed. Peaches from the “Laskava” (native Bulgarian) variety were used as the main ingredient. The new sorbet matrices were characterized based on their moisture and ash content, overrun, melting behavior, melting rate, water holding capacity, pH, nutritional data, soluble solids content, titratable acidity, vitamin C content, total phenolic content and antioxidant activity. The microbial load and CIELAB color of the sorbet alternatives was also evaluated. A sensory evaluation revealed the most preferred variant. Panelists evaluated the appearance (n = 6), aroma (n = 5), flavor (n = 5), mouthfeel (n = 7), and aftertaste (n = 5). The soluble solids content varied from 17.50 to 33.03%, the ash content from 0.36 to 5.21%, the moisture content from 63.77 to 80.21%. The studied sorbet matrices have an overrun in the range from 8.11 to 12.32%. Results showed that a potential for the development of peach sorbet matrices with added value and a reasonable consumer acceptability exists. Further research can perfect the recipe and provide a reference for other frozen desserts.

The aim of this study is to characterize the bioactivity of mycelial biomass and crude exopolysaccharides (EPS) produced by Trametes versicolor NBIMCC 8939 and to reveal its nutraceutical potential. The EPS (1.58 g/L) were isolated from a culture broth. The macrofungal biomass was rich in protein, insoluble dietary fibers and glucans. The amino acid composition of the biomass was analyzed and 18 amino acids were detected. Three mycelial biomass extracts were prepared and the highest total polyphenol content (16.11 ± 0.14 mg GAE/g DW) and the total flavonoid content (5.15 ± 0.03 mg QE/g DW) were found in the water extract. The results indicated that the obtained EPS were heteropolysaccharides with glucose as the main building monosaccharide and minor amounts of mannose, xylose, galactose, fucose and glucuronic acid. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the complex structure of the crude EPS. Five probiotic lactic acid bacteria strains were used for the determination of the prebiotic effect of the crude EPS. The anti-inflammatory potential was tested in vitro using cell line HT-29. The significant decrease of IL-1 and IL-8 and increase of TGF-beta expression revealed anti-inflammatory potential of the crude exopolysaccharides from T. versicolor.

Changing nutritional demands, in combination with the global trend for snacking, sets a goal for preparing food products for direct consumption with certain beneficial properties. This study was designed to investigate the quality characteristics of raw vegan bonbons enriched with lyophilized peach powder. Three types of formulations were prepared in which 10%, 20%, and 30% of lyophilized peach powder were, respectively, added. The newly developed vegan products were characterized in terms of their physical (moisture, ash, color, water activity), microbiological, and nutritional characteristics. Their antioxidant activity, flavonoid, and phenolic content were also evaluated. Considering the content of the bonbons, the reported health claims indicate that they are sources of fiber, with no added sugar, and contain naturally occurring sugars. The color measurements demonstrated similarity in the values. This study showed that there is significant potential in the production of healthy snacks for direct consumption, with beneficial properties.

Nowadays, the search for food-suitable plant proteins is a great challenge. In addition to their sustainability and nutritional value, the focus is more and more on possible positive interactions with human health. To date, the presence of bioactive peptides encrypted in the structure of protein opens new perspectives, addressing the food industry’s request for new ingredients with technological properties and also the nutraceutical and pharmaceutical sectors based on multifunctional health applications. Lupinus is a sustainable genus of the legume family Fabaceae, and the lupin seed-derived bioactive peptides have demonstrated different effects including anti-inflammatory, antidiabetic, antioxidant, antibacterial, hypocholesterolemic, and antihypertensive activities. This review aims to discuss the current knowledge on lupin protein and their bioactive peptides, highlighting the documented health claims, but also the possibility of allergenicity and the work to be done for the development of new functional products.

Burdock (Arctium lappa L.) roots are traditionally used in folk medicine as diuretic and curing rheumatism, gastritis, gout, throat pain, arthritis and rashes. These pharmacological properties are due to many bioactive compounds such as flavonoids and fructooligosaccharides. Nowadays, the the application of “green” methods for extraction of natural compounds gains more and more attention. The object of the current research was to determine inulin and sugars content, phenolic content and antioxidant potential in 70% ethanol and water extracts obtained by two “green“ extraction methods, namely pressure-liquid extraction and ultrasound-assisted techniques. The content of total fructans, as well as inulin and sugars were analyzed by spectrophotometric resorcinol-thiourea method and high-performance liquid chromatography with refractive index detection. Total phenols and flavonoids were determined by Folin-Chiocalteu and Al(NO3)3 reagents. Antioxidant activity was evaluated by four reliable methods (DPPH, ABTS, FRAP and CUPRAC). The established inulin content varied from 0.27 to 4.0 g/100 g dw in prevalence of the ultrasound-assisted extract obtained with water. Additionally, the established phenolic compounds content (from 10.35 to 18.16 mg gallic acid equivalent (GAE)/g dw) and antioxidant activities demonstrated the burdock roots as potential source phytonutrients with health beneficial properties.

Nowadays, food is no longer just for nutrition. Consumers are more demanding and expect to get health benefits from their daily meals. Various areas of the food industry are in great demand of functional chemicals to enhance the taste and nutritional value of their products. Probiotic bacteria have already been part of the human’s routine for good gut microbiota maintenance in terms of pharmaceutical products. Their incorporation in food however is a challenging task that offers great opportunities but has limitations as well. Specifically, the purpose of this review is to emphasize the importance of probiotics in food, to assess their survival through gastrointestinal tract, and to highlight the recent advances in approaches for their improved viability.

The volatile compounds of eight peach varieties (Prunus persica L.)—“Filina”, “Gergana”, “Ufo-4”, “July lady”, “Laskava”, “Flat Queen”, “Evmolpiya”, and “Morsiani 90”—growing in Bulgaria were analyzed for the first time. Gas chromatography–mass spectrometry (GC–MS) analysis and the HS-SPME technique revealed the presence of 65 volatile compounds; the main identified components were aldehydes, esters, and fatty acids. According to the provided principal component analysis (PCA) and hierarchical cluster analysis (HCA), the relative quantities of the identified volatile compounds depended on the studied peach variety. The results obtained could be successfully applied for the metabolic chemotaxonomy of peaches.

Members of the bacterial genus Bacillus are known as producers of a broad spectrum of antibiotic compounds of proteinaceous nature that possess inhibitory activity against different saprophytic and pathogenic microorganisms. In the current research, a peptide synthesized by Bacillus methylotrophicus strain BM47, previously isolated from a natural thermal spring in Bulgaria, was identified and characterized as a bacteriocin. In vitro antimicrobial screening of the crude bacteriocin substance of B. methylotrophicus BM47 showedn activity against the plant pathogenic fungi Fusarium moniliforme, Aspergillus awamori, Penicillium sp., Aspergillus niger and Gram-negative bacterium Pseudomonas aeruginosa. The antimicrobial activity of the crude bacteriocin substance was partially inhibited by the enzymes trypsin, Alcalase®, Savinase®, proteinase K, papain and Esperase®, while catalase was not effective. The crude bacteriocin substance was relatively pH resistant, but sensitive to the action of heat and most organic solvents and detergents tested. To obtain the active protein fractions, crude bacteriocin substance was purified by fast protein liquid chromatography (FPLC) using a strong anion exchange column. Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis demonstrated that the purified bacteriocin had molecular mass of 19 578 Da. The amino acid analysis performed by high-performance liquid chromatography (HPLC) revealed that the isolated bacteriocin consisted of 17 types of amino acids, with the highest mol fraction expressed as percent of serine (29.3), valine (10.3), alanine (9.8) and tyrosine (7.1).

It has long been recognized that fruits are healthy diet compounds since they are excellent sources of health beneficial bioactive components (polyphenols, minerals, vitamins, organic acids, etc.). The diversification of the consumer’s taste calls for an expansion of food options and novel ingredients. The excessive refined sugar intake in recent years demands for the incorporation of sugar alternatives in popular dessert recipes, and high calorie obesogenic foods in general. Puddings are a well-known food choices introduced in the human diet at a very early age because of its easy and high digestion. Four formulations with two types of starch (corn and rice) were selected as objects of analysis. Nectarines were incorporated as a purée and lyophilized powder. The nectarine variety “Gergana” is a local variety used for preparations with proven beneficial properties. The study aimed to analyze the physical (moisture, ash, color, water-holding capacity, water activity, density, and syneresis), rheological (firmness, gumminess, cohesiveness, springiness, and chewiness), nutritional, and sensory characteristics of the nectarine-enriched puddings. The outcomes obtained from this study provide significant information about the possible application of the formulations in the children’s daily menus. All four formulations had distinct peachy aroma. The formulations prepared with nectarine purée resulted in better sensory perception, better texture, and better water holding capacity. The formulations prepared with lyophilized fruit had similar CIELAB color values. The same trend was observed in the nectarine purée formulations. At this point, the formulation prepared with lyophilized fruit and rice starch showed the most promising results. Sufficient evidence leads to further exploration of the perspective of fruit-enriched puddings in order to improve their technological and health-promoting properties.

It has been long recognized that fruits are healthy diet compounds as they are excellent sources of health-beneficial bioactive components (polyphenols, minerals, vitamins, organic acids, etc.). The diversification of the consumer’s taste calls for an expansion of food options and novel ingredients. Puddings are a well-known food choice introduced in the human diet at a very early age because of their easy and high digestion. Four formulations with two types of starch (corn and rice) were selected as object of analysis. Nectarines were incorporated as a purée, and lyophilized powder. The nectarine variety “Gergana”, used for the preparations, is a local variety with proven beneficial properties. The study aimed at analyzing the physical (moisture, ash, color, water-holding capacity, water activity, density and syneresis), textural (firmness, gumminess, cohesiveness, springiness, and chewiness), nutritional, and sensory characteristics of the nectarine-enriched puddings. The outcomes obtained from this study provided significant information about the possible application of the formulations in the children’s daily menus. All four formulations had distinct peachy aroma. The formulations prepared with nectarine purée resulted in a better sensory perception about their texture, and better water-holding capacity. At this point, the formulation prepared with lyophilized fruit and rice starch has the most promising results. Sufficient evidence leads to further exploration of the perspective of fruit-enriched puddings in order to improve their technological and health-promoting properties.

The inhibition of certain digestive enzymes by target food matrices represents a new approach in the treatment of socially significant diseases. Proving the ability of fruits to inhibit such enzymes can support the inclusion of specific varieties in the daily diets of patients with diabetes, obesity, Alzheimer’s disease, etc., providing them with much more than just valuable micro- and macromolecules. The current study aimed atidentifying and comparing the GC-MS metabolic profiles of eight peach varieties (“Filina”, “Ufo 4, “Gergana”, “Laskava”, “July Lady”, “Flat Queen”, “Evmolpiya”, and “Morsiani 90”) grown in Bulgaria (local and introduced) and to evaluate the inhibitory potential of their extracts towards α-glucosidase, α-amylase, lipase, and acetylcholinesterase. In order to confirm samples’ differences or similarities, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were also applied to the identified metabolites. The results provide important insights into the metabolomic profiles of the eight peach varieties and represent a first attempt to characterize the peels of the peach varieties with respect to α-glucosidase-, α-amylase-, lipase-, and acetylcholinesterase-inhibitory activities. All of the studied peach extracts displayed inhibitory activity towards α-glucosidase (IC50: 125–757 mg/mL) and acetylcholinesterase (IC50: 60–739 mg/mL), but none of them affected α-amylase activity. Five of the eight varieties showed inhibitory activity towards porcine pancreatic lipase (IC50: 24–167 mg/mL). The obtained results validate the usefulness of peaches and nectarines as valuable sources of natural agents beneficial for human health, although further detailed investigation should be performed in order to thoroughly identify the enzyme inhibitors responsible for each activity.

Peaches are one of the most preferred seasonal fruits, and a reliable source of nutrients. They possess biologically active substances that largely differ among varieties. Hence, revealing the potential of several late season peaches is of present interest. Three commonly consumed varieties (“Flat Queen”; “Evmolpiya”; “Morsiani 90”) were studied in terms of nutritive and phytochemical content, as well as antioxidant activity with the use of reliable spectrophotometric and High Performance Liquid Chromatographic (HPLC) methods. An analysis of the soil was also made. The phytochemical data were subjected to principal component analysis in order to evaluate their relationship. The “Morsiani 90” variety had the highest minerals concentration (2349.03 mg/kg fw), total carbohydrates (16.21 g/100 g fw), and α-tocopherol (395.75 µg/100 g fresh weight (fw)). Similar amounts of TDF (approx. 3 g/100 g fw) were reported for all three varieties. “Flat Queen’s” peel extract was the richest in monomeric anthocyanins (2279.33 µg cyanidin-3-glucoside (C3GE)/100 g fw). The “Morsiani 90” variety extracts had the highest antioxidant potential, defined by 2,2-diphenil-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) and cupric ion-reducing antioxidant capacity (CUPRAC) assays.

This study evaluates the phytochemical composition and ability of herbal preparation AyuFertin, supplemented shortly after calving, to resume the cyclic ovarian activity in postpartum Bulgarian Murrah buffaloes. In total, 13 healthy Bulgarian Murrah buffaloes at the age of 4–10 years, calved in March–April 2019 were involved in the experiment. Seven experimental buffaloes were treated individually per os with AyuFertin according to producer instruction. All animals were subjected to regular ultrasound examination of ovaries. GC-MS analysis of fatty acids composition and HPLC-DAD analysis of carotenoid and tocopherol content in AyuFertin were conducted. The determination of estrus occurrence and natural mating were done by a fertile bull. The development of the large follicles (12.5–14.3 mm) in 85.7% of treated animals was observed on day 24 postpartum compared to 0% in controls. Clinical signs of estrus were recorded in 71.4% of the animals, followed by an 80% pregnancy rate versus 16% in controls within 70 days after calving. In conclusion, the supplementation of the bioactive herbal product AyuFertin from day 21 postpartum can stimulate the follicular growth in the buffalo’s ovary, which leads to the development of follicles with ovulatory capacity, followed by successful ovulation. The above-mentioned treatment resulted in a better pregnancy rate in the treated multiparous compared to the control buffaloes bred by natural service.

Fruits contain a number of useful substances including antioxidants. Their bio-accessibility after passing through the digestive tract is of primary importance when considering their benefits. In this respect, we investigated the effect of in vitro digestion on the phytochemicals of eight fruit juices. Freshly prepared juices from pomegranate, orange and grapefruit were used as well as commercially available juices from cherry, black grapes and aloe vera, blackberry and chokeberry, and two types of chokeberry and raspberries. Spectrophotometric and HPLC methods were used in order to analyse the sugar content, the total phenolic (TPC) and flavonoid contents (TFC), anthocyanins, phenolic acids and antioxidant activity. Principle component analysis was used to explain the differentiation among the types of fruit juice. Sugar recovery variation was between 4–41%. The bio-accessibility of TPC ranged from 13.52–26.49% and of flavonoids between 24.25–67.00%. The pomegranate juice and the juice of black grapes and aloe vera kept 58.12 and 50.36% of their initial anthocyanins content, while for the other samples less than 1.10% was established. As a result, a maximum of 30% remaining antioxidant activity was measured for some of the samples, but for most this was less than 10%. In conclusion, fruit juices are a rich source of biologically active substances, but a more detailed analysis of food transformation during digestion is needed.

Exploring the chemical composition and biological activity of different fruit varieties is essential for the valorization of their health claims. The current study focuses on a detailed comparative analysis of three early- and two mid-ripening peach varieties: “Filina” (peach), “July Lady” (peach), “Laskava” (peach), “Gergana” (nectarine), and “Ufo 4” (flat peach). They were characterized in terms of essential nutrients such as carbohydrates (sugars and dietary fibers), amino acid content, and lipids as well as mineral content, fat-soluble vitamins, carotenoids, and chlorophyll. Polyphenolic compounds and the related antioxidant activity were also assessed. The methanolic extract of the peel seems to be richer in the studied biologically active substances compared to the fleshy part of the fruit. Anthocyanins were most abundant in “Gergana” and “July Lady” extracts (6624.8 ± 404.9 and 7133.6 ± 388.8 µg cyanidin-3-glucoside/100 g fw, resp.). The total phenol content of the samples varied from 34.11 ± 0.54 to 157.97 ± 0.67 mg gallic acid equivalents (GAE)/100 g fw. “Filina” and “July Lady” varieties possessed the highest antioxidant activity. Overall, the results of this study confirm that the studied peach varieties have satisfactory nutritional value and are potential sources of biologically active substances. Each variety represents an individual palette of nutrients that should be considered separately from the other.

The purpose of the present study was to investigate the antioxidant activity and fructans content in ethanol and water extracts of roots of elecampane (Inula helenium L.), a Bulgarian medicinal plant. The extraction procedure included 95% (v/v) ethanol extraction and subsequent water treatment. The antioxidant activity was evaluated by several reliable methods such as DPPH-, ABTS-, FRAP- and CUPRAC-assays, as well as the total phenolic content. In addition, the total fructans and sugar content were determinated by spectrophotomeric, TLC and HPLC-RID methods. The level of fructans in ethanol extracts was 14.1 g / 100 g dry weight, as nystose and 1-kestose were only 0.3 g / 100 g dry weight, and 0.5 g / 100g dry weight, respectively. The absence of fructooligosacharides and sugars in water extracts after the ethanol pretreatment was established. Inulin content was evaluated to be 32 g / 100 g dry weight. The metabolites profile of roots revealed their potential application as radical scavengers due to the presence of polyphenols. Therefore, the root extracts of elecampane could be assumed as a rich source of biologically active substance, in particular dietary fiber with potential prebiotic effect, due to the presence of polysaccharide inulin and fructooligosacharides.

This work aimed to study the antioxidant activity of a quercetin-containing flavonoid extract (FQЕ) obtained from Sophora japonica L. flower buds rich in quercetin (91.6%). Radical scavenging activity was analyzed towards the synthetic radicals DPPH• and ABTS•+ and antioxidant activity was evaluated applying the method of oxygen consumption in a model system containing methyl linoleate. Model food systems of lard and sunflower oil were explored by the application of Rancimat method and chicken as a real food system was investigated by the thiobarbituric acid test. Results showed a high radical scavenging activity and antioxidant capacity of QFE similar to those of the pure flavonoid quercetin.