Vassilis Athanasiadis | University of Thessaly (original) (raw)

Publications in International Journals by Vassilis Athanasiadis

Polyphenol-containing extracts from olive (Olea europaea) leaves (OLL) were obtained using a glyc... more Polyphenol-containing extracts from olive (Olea europaea) leaves (OLL) were obtained using a glycerol-based deep eutectic solvent (DES) and a combination of DES with methyl β-cyclodextrin (m-β-CD). The extracts were stored at various temperatures for a period of 20 days and the reducing power (PR) was monitored to trace changes in the antioxidant potency of the extracts. Over the examination period and at every temperature tested, PR displayed a constant decline, which followed pseudo zero-order kinetics. The determination of the decay constants indicated that the presence of m-β-CD acted protectively, slowing down the progression of the PR decline. Examination of the polyphenolic profiles using liquid chromatography–diode array–mass spectrometry showed that after storage for 20 days at 50 °C, some major polyphenols occurring in OLL suffered extended degradation. The formation of a yellow pigment in the extracts stored in DES but not in aqueous ethanol suggested that polyphenol oxidation did occur during storage. It was concluded that the oxidation of some OLL components was rather responsible for the PR decline observed.

Fruits and vegetables are major sources of antioxidants. These are substances that remove free-ra... more Fruits and vegetables are major sources of antioxidants. These are substances that remove free-radical intermediates by being oxidized themselves and delay or inhibit other oxidation reactions. Recent studies make clear that an antioxidant-rich diet acts as a health protecting factor. The antioxidant that was used in this study was 2,5-dimethyl-4-hydroxy-3(2H)-furanone (HDMF). Two frying methods (with and without antioxidant) were used: the first one with no replenishment of oil and the second one with frequent replenishment of oil. As it was proved by the induction period, using the Rancimat method, HDMF increased the resistance against oxidation not only of the frying oils but also of the oil that was absorbed by the chips. The results were in line with those of croissants when they were baked with or without HDMF. Taste panel test confirmed those results as panelists showed a clear preference for those products that were protected against oxidation by HDMF.

Industrial activity has contributed to potentially toxic metal pollution in various ecosystems th... more Industrial activity has contributed to potentially toxic metal pollution in various ecosystems throughout the world. In this study, the ability of humic and fulvic acids (isolated from lignite with a simple, rapid, and inexpensive method) to reduce toxic metals’ concentration of contaminated water is examined. More specifically, the effect of these compounds is tested on water contaminated (at various concentrations) with Cd, Cr, Cu, Ni, and Pb. The determination is performed by inductively coupled plasma-optical emission spectrometry. The maximum binding capacity is presented by fulvic acids in the following order Cr>Pb>Ni>Cu>Cd (97.8, 96.5, 95.4, 95.1, and 83.3%, respectively), while for humic acids it is Pb>Ni>Cr>Cu>Cd (81.3, 70.7, 68.6, 67.0, and 66.8%, respectively). The binding activity is also tested on water contaminated with two metals simultaneously. In these cases, the existence of two metals in water changes the reduction ability of humic and fulvic acids (positively or negatively).

Olive leaf (OLL) extracts contain a high load of antioxidant polyphenols with significant pharmac... more Olive leaf (OLL) extracts contain a high load of antioxidant polyphenols with significant pharmacological potency. In this study, the use of a novel natural deep eutectic solvent enabled the effective extraction of OLL polyphenols and their testing as radical scavengers, in the presence or absence of methyl β-cyclodextrin (m-β-CD), using descriptive kinetics. Testing was extended to include interactions with ascorbic acid—a natural powerful antioxidant—by implementing a response surface methodology. The kinetic study showed that m-β-CD may hinder the radical scavenging effect of OLL extracts, yielding lower stoichiometry upon reaction with the radical probe 2,2-diphenyl-1-picrylhydrazy (DPPH). The extension of the reaction time to determine the total stoichiometry confirmed this effect. As a further concurrence, the interactions of OLL extracts with ascorbic acid showed lower radical scavenging performance in the presence of m-β-CD. These results were discussed on the grounds of the role that m-β-CD may play in similar systems.

A novel deep eutectic solvent (DES) with optimised composition was used to evaluate the effect of... more A novel deep eutectic solvent (DES) with optimised composition was used to evaluate the effect of methyl β-cyclodextrin (CD) on the efficiency of polyphenol extraction from Olea europaea leaves (OLLs). The process developed was based on a 2 3 full-factorial design and response surface methodology to assess the simultaneous effect of CD concentration (C CD), liquid-to-solid ratio (R L/S) and temperature (T). Under optimised conditions (C CD = 9%, R L/S = 40 mL g −1 , T = 51 °C), the yield in total polyphenols (Y TP) was 116.65 ± 3.60 mg gallic acid equivalents per g dry weight. This value was significantly higher than that determined for the extraction performed with 60% aqueous etha-nol. The extraction kinetics also showed that the extraction rate was slowed down in the presence of CD, yet the higher extraction capacity of the DES/CD medium was confirmed. Characterisation of the extracts obtained with DES/CD and DES by means of liquid chromatography-mass spectrometry demonstrated that there was no selective extraction of any particular polyphenol, suggesting that CD acted merely as an extraction booster.

A number of biological activities have been attributed to polyphenolic substances occurring in th... more A number of biological activities have been attributed to polyphenolic substances occurring in the leaves of the olive tree (O. europaea), an olive oil industry waste material, and for this reason several extraction processes have been developed for the efficient recovery of these phytochemicals. The study presented herein describes for the first time the use of an eco-friendly deep eutectic solvent (DES) as a highly effective solvent for the extraction of polyphenols from olive tree leaves. Initially, a central composite design was implemented to optimise solvent composition and liquid-to-solid ratio and then a kinetic assay was performed to investigate diffusivity (De) and temperature effects. The maximum total polyphenol yield was 106.25 mg gallic acid equivalents per g dry weight, achieved at 70 °C. This value was by 18% higher than that achieved with 60% aqueous methanol. Furthermore, the DES extract exhibited significantly higher antiradical activity and reducing power. Temperature increase up to 70 °C was shown to boost De and the activation energy determined for the process was 29.55 kJ mol-1. Characterisation of the extract by means of liquid chromatography-diode array-mass spectrometry showed oleuropein and certain flavone glycosides to be the major polyphenolic constituents.

Moringa oleifera tree was cultivated for the first time in the mild temperate climate of Greece. ... more Moringa oleifera tree was cultivated for the first time in the mild temperate climate of Greece. Moringa oleifera leaf protein and amino acid content, total phenols and flavonols, lipids, fatty acids, ash and minerals, dietary fiber and carbohydrates, carotenoids, and vitamins C and E were determined. Leaves were high in protein content (26.3%), including all the essential amino acids. They also contained 4512.2 mg GAE.100 g –1 DM of total phenols and were rich in flavonols (myricetin, quercetin, and kaempherol at 649.8, 77.2, and 37.2 mg.

Mastic is a well-known natural resin from the trunk and branches, of Pistacia lentiscus var. chia... more Mastic is a well-known natural resin from the trunk and branches, of Pistacia lentiscus var. chia (Anacardiaceae), which is grown as endemic only in the Greek island of Chios. During this work, a total mastic gum extract was prepared after removal of the contained insoluble polymer in order to ameliorate solubility and enhance in vivo activity. To overcome the drawbacks (i.e solubility, bioavailability, etc.) of mastic gum extracts (acidic and neutral fraction), the selection of a suitable carrier is crucial. Three different methods of preparation, thin-film evaporation, freezing-thawing, and ethanol injection were used for the preparation of liposomes consisting of Phosphatidylcholine (PC) and Cholesterol (CH). The effect of PC: CH molar ratio on the percentage of mastic extract encapsulated was investigated. Mastic gum extracts components-liposomes interaction was studied using Fourier transform infrared (FT-IR) spectroscopy. The effects of different preparation methods on the physicochemical properties of colloidal systems were evaluated by means of surface morphology, field emission Scanning Electron Microscopy (SEM), and size distribution using a particle size analyzer. For the determination of the antioxidant activity two methods were used: I) The Rancimat method where the protection factor was determined for each sample and compared with known antioxidants. II) Differential Scanning Calorimetry (DSC) where the temperature of oxidation for each sample was determined. Moreover, the crude extract (EtOAc-MeOH) of mastic, as well as, its acidic and neutral fractions was assayed against a panel of 9 human and food pathogenic gram (±) bacteria and fungi.

This work was dedicated to reporting the full chemical and physical characterisation of Crambe ab... more This work was dedicated to reporting the full chemical and physical characterisation of Crambe abyssinica Hochst. seed oil. The oil from the seeds was extracted using n-hexane. The seeds contain about 30 % oil. Density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, the relative position of fatty acids in C1 and C3 carbon glycerol, sterols, tocopherols, peroxide value, $ \mathop E\nolimits_{{1{\text{cm}}}}^{1\,\% } $ at 232 nm, and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially C22:1 (63.77 %). The dominant saturated acid was C22:0 (2.14 %). The oil was also found to contain high levels of β-sitosterol (51.93 %), campestanol (21.98 %), and brassicasterol (12.35 %). α-, γ-, and δ-Tocopherols were detected up to levels of 7.67, 125.04, and 3.99 mg/kg, respectively. The induction period (at 110 °C and 20 l/h) of the oil was 8.83 h. The relative position of fatty acids in C1 and C3 position was as follows: linoleic 0.45 %, oleic 8.84 %, and erucic 90.72 %. The thermal profile of the oil presented a single peak at −20.94 °C.

Natural antioxidants derived from plant sources attract considerable scientific interest. While c... more Natural antioxidants derived from plant sources attract considerable scientific interest. While classic extraction methods consume high volumes of toxic organic solvents, cloud point extraction requires surfactant not exceeding 15% of the waste volume. In preliminary tests, the suitability of various low hazard surfactants (Span 20, PEG 400, Tween 80 and 20) was explored for separation of phenols and carotenoids from olive mill wastewater and red-flesh orange juice. Tween 80 showed the highest recovery and further applied to the next experiments. The most appropriate surfactant concentrations were 5% (for olive mill wastewater) and 7% (for orange juice) as indicated by recovery % and the rest cloud point extraction parameters (analyte concentration, concentration factor, and phase volume ratio). A double step CPE with 5% + 5% of Tween 80 recovered up to 94.4% of the total phenols from olive mill wastewater, while a 7% + 7% of Tween 80 recovered up to 72.4% of the total carotenoids from orange juice. Evaluation of the final effects and extraction efficiency of single and double step cloud point extraction shows that double step scheme seems to be preferable in both cases. Finally, phenols and carotenoids recovered by Tween 80 maintained high antiradical activity (DPPH test).

The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina... more The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina was tested against Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Candida albicans, C. tropicalis and C. glabrata. The oil proved effective against all of the tested microorganisms. Standard antibiotics (netilmycin, 5-flucytocine, intraconazole and 7-amino-4-methylcoumarin-3-acetic acid) were used for comparison. The resistance to oxidation of the extracted seed oil was also determined.

The possibility to increase the nutritional value of table olives using polyphenols extracted fro... more The possibility to increase the nutritional value of table olives using polyphenols extracted from olive leaves was studied. Leaves were subjected to extraction using water with proportions of 1%, 5% and 10% of leaves and various temperatures and times (room temperature/24 h, 40 °C/10 min and 70 °C/5 min). The antioxidant activity of extracts was determined using the Rancimat method and their content in oleuropein and hydroxytyrosol was determined by HPLC. The extract with the highest antioxidant activity and polyphenol content (10% ratio of olive leaves extracted at room temperature for 24 h) was used for the treatment of debittered table olives. The treated and untreated olives were subjected to determination of their α-tocopherol, oleuropein and hydroxytyrosol content. A 457% increase was observed for oleuropein and 109% for hydroxytyrosol content after treatment. Sensory evaluation of treated table olives showed an increase in bitterness. However, treated and untreated table olives showed equal overall acceptability and overall preference.

Presentations in Conferences by Vassilis Athanasiadis

Polyphenol-containing extracts from olive (Olea europaea) leaves (OLL) were obtained using a glyc... more Polyphenol-containing extracts from olive (Olea europaea) leaves (OLL) were obtained using a glycerol-based deep eutectic solvent (DES) and a combination of DES with methyl β-cyclodextrin (m-β-CD). The extracts were stored at various temperatures for a period of 20 days and the reducing power (PR) was monitored to trace changes in the antioxidant potency of the extracts. Over the examination period and at every temperature tested, PR displayed a constant decline, which followed pseudo zero-order kinetics. The determination of the decay constants indicated that the presence of m-β-CD acted protectively, slowing down the progression of the PR decline. Examination of the polyphenolic profiles using liquid chromatography–diode array–mass spectrometry showed that after storage for 20 days at 50 °C, some major polyphenols occurring in OLL suffered extended degradation. The formation of a yellow pigment in the extracts stored in DES but not in aqueous ethanol suggested that polyphenol oxidation did occur during storage. It was concluded that the oxidation of some OLL components was rather responsible for the PR decline observed.

Fruits and vegetables are major sources of antioxidants. These are substances that remove free-ra... more Fruits and vegetables are major sources of antioxidants. These are substances that remove free-radical intermediates by being oxidized themselves and delay or inhibit other oxidation reactions. Recent studies make clear that an antioxidant-rich diet acts as a health protecting factor. The antioxidant that was used in this study was 2,5-dimethyl-4-hydroxy-3(2H)-furanone (HDMF). Two frying methods (with and without antioxidant) were used: the first one with no replenishment of oil and the second one with frequent replenishment of oil. As it was proved by the induction period, using the Rancimat method, HDMF increased the resistance against oxidation not only of the frying oils but also of the oil that was absorbed by the chips. The results were in line with those of croissants when they were baked with or without HDMF. Taste panel test confirmed those results as panelists showed a clear preference for those products that were protected against oxidation by HDMF.

Industrial activity has contributed to potentially toxic metal pollution in various ecosystems th... more Industrial activity has contributed to potentially toxic metal pollution in various ecosystems throughout the world. In this study, the ability of humic and fulvic acids (isolated from lignite with a simple, rapid, and inexpensive method) to reduce toxic metals’ concentration of contaminated water is examined. More specifically, the effect of these compounds is tested on water contaminated (at various concentrations) with Cd, Cr, Cu, Ni, and Pb. The determination is performed by inductively coupled plasma-optical emission spectrometry. The maximum binding capacity is presented by fulvic acids in the following order Cr>Pb>Ni>Cu>Cd (97.8, 96.5, 95.4, 95.1, and 83.3%, respectively), while for humic acids it is Pb>Ni>Cr>Cu>Cd (81.3, 70.7, 68.6, 67.0, and 66.8%, respectively). The binding activity is also tested on water contaminated with two metals simultaneously. In these cases, the existence of two metals in water changes the reduction ability of humic and fulvic acids (positively or negatively).

Olive leaf (OLL) extracts contain a high load of antioxidant polyphenols with significant pharmac... more Olive leaf (OLL) extracts contain a high load of antioxidant polyphenols with significant pharmacological potency. In this study, the use of a novel natural deep eutectic solvent enabled the effective extraction of OLL polyphenols and their testing as radical scavengers, in the presence or absence of methyl β-cyclodextrin (m-β-CD), using descriptive kinetics. Testing was extended to include interactions with ascorbic acid—a natural powerful antioxidant—by implementing a response surface methodology. The kinetic study showed that m-β-CD may hinder the radical scavenging effect of OLL extracts, yielding lower stoichiometry upon reaction with the radical probe 2,2-diphenyl-1-picrylhydrazy (DPPH). The extension of the reaction time to determine the total stoichiometry confirmed this effect. As a further concurrence, the interactions of OLL extracts with ascorbic acid showed lower radical scavenging performance in the presence of m-β-CD. These results were discussed on the grounds of the role that m-β-CD may play in similar systems.

A novel deep eutectic solvent (DES) with optimised composition was used to evaluate the effect of... more A novel deep eutectic solvent (DES) with optimised composition was used to evaluate the effect of methyl β-cyclodextrin (CD) on the efficiency of polyphenol extraction from Olea europaea leaves (OLLs). The process developed was based on a 2 3 full-factorial design and response surface methodology to assess the simultaneous effect of CD concentration (C CD), liquid-to-solid ratio (R L/S) and temperature (T). Under optimised conditions (C CD = 9%, R L/S = 40 mL g −1 , T = 51 °C), the yield in total polyphenols (Y TP) was 116.65 ± 3.60 mg gallic acid equivalents per g dry weight. This value was significantly higher than that determined for the extraction performed with 60% aqueous etha-nol. The extraction kinetics also showed that the extraction rate was slowed down in the presence of CD, yet the higher extraction capacity of the DES/CD medium was confirmed. Characterisation of the extracts obtained with DES/CD and DES by means of liquid chromatography-mass spectrometry demonstrated that there was no selective extraction of any particular polyphenol, suggesting that CD acted merely as an extraction booster.

A number of biological activities have been attributed to polyphenolic substances occurring in th... more A number of biological activities have been attributed to polyphenolic substances occurring in the leaves of the olive tree (O. europaea), an olive oil industry waste material, and for this reason several extraction processes have been developed for the efficient recovery of these phytochemicals. The study presented herein describes for the first time the use of an eco-friendly deep eutectic solvent (DES) as a highly effective solvent for the extraction of polyphenols from olive tree leaves. Initially, a central composite design was implemented to optimise solvent composition and liquid-to-solid ratio and then a kinetic assay was performed to investigate diffusivity (De) and temperature effects. The maximum total polyphenol yield was 106.25 mg gallic acid equivalents per g dry weight, achieved at 70 °C. This value was by 18% higher than that achieved with 60% aqueous methanol. Furthermore, the DES extract exhibited significantly higher antiradical activity and reducing power. Temperature increase up to 70 °C was shown to boost De and the activation energy determined for the process was 29.55 kJ mol-1. Characterisation of the extract by means of liquid chromatography-diode array-mass spectrometry showed oleuropein and certain flavone glycosides to be the major polyphenolic constituents.

Moringa oleifera tree was cultivated for the first time in the mild temperate climate of Greece. ... more Moringa oleifera tree was cultivated for the first time in the mild temperate climate of Greece. Moringa oleifera leaf protein and amino acid content, total phenols and flavonols, lipids, fatty acids, ash and minerals, dietary fiber and carbohydrates, carotenoids, and vitamins C and E were determined. Leaves were high in protein content (26.3%), including all the essential amino acids. They also contained 4512.2 mg GAE.100 g –1 DM of total phenols and were rich in flavonols (myricetin, quercetin, and kaempherol at 649.8, 77.2, and 37.2 mg.

Mastic is a well-known natural resin from the trunk and branches, of Pistacia lentiscus var. chia... more Mastic is a well-known natural resin from the trunk and branches, of Pistacia lentiscus var. chia (Anacardiaceae), which is grown as endemic only in the Greek island of Chios. During this work, a total mastic gum extract was prepared after removal of the contained insoluble polymer in order to ameliorate solubility and enhance in vivo activity. To overcome the drawbacks (i.e solubility, bioavailability, etc.) of mastic gum extracts (acidic and neutral fraction), the selection of a suitable carrier is crucial. Three different methods of preparation, thin-film evaporation, freezing-thawing, and ethanol injection were used for the preparation of liposomes consisting of Phosphatidylcholine (PC) and Cholesterol (CH). The effect of PC: CH molar ratio on the percentage of mastic extract encapsulated was investigated. Mastic gum extracts components-liposomes interaction was studied using Fourier transform infrared (FT-IR) spectroscopy. The effects of different preparation methods on the physicochemical properties of colloidal systems were evaluated by means of surface morphology, field emission Scanning Electron Microscopy (SEM), and size distribution using a particle size analyzer. For the determination of the antioxidant activity two methods were used: I) The Rancimat method where the protection factor was determined for each sample and compared with known antioxidants. II) Differential Scanning Calorimetry (DSC) where the temperature of oxidation for each sample was determined. Moreover, the crude extract (EtOAc-MeOH) of mastic, as well as, its acidic and neutral fractions was assayed against a panel of 9 human and food pathogenic gram (±) bacteria and fungi.

This work was dedicated to reporting the full chemical and physical characterisation of Crambe ab... more This work was dedicated to reporting the full chemical and physical characterisation of Crambe abyssinica Hochst. seed oil. The oil from the seeds was extracted using n-hexane. The seeds contain about 30 % oil. Density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, the relative position of fatty acids in C1 and C3 carbon glycerol, sterols, tocopherols, peroxide value, $ \mathop E\nolimits_{{1{\text{cm}}}}^{1\,\% } $ at 232 nm, and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially C22:1 (63.77 %). The dominant saturated acid was C22:0 (2.14 %). The oil was also found to contain high levels of β-sitosterol (51.93 %), campestanol (21.98 %), and brassicasterol (12.35 %). α-, γ-, and δ-Tocopherols were detected up to levels of 7.67, 125.04, and 3.99 mg/kg, respectively. The induction period (at 110 °C and 20 l/h) of the oil was 8.83 h. The relative position of fatty acids in C1 and C3 position was as follows: linoleic 0.45 %, oleic 8.84 %, and erucic 90.72 %. The thermal profile of the oil presented a single peak at −20.94 °C.

Natural antioxidants derived from plant sources attract considerable scientific interest. While c... more Natural antioxidants derived from plant sources attract considerable scientific interest. While classic extraction methods consume high volumes of toxic organic solvents, cloud point extraction requires surfactant not exceeding 15% of the waste volume. In preliminary tests, the suitability of various low hazard surfactants (Span 20, PEG 400, Tween 80 and 20) was explored for separation of phenols and carotenoids from olive mill wastewater and red-flesh orange juice. Tween 80 showed the highest recovery and further applied to the next experiments. The most appropriate surfactant concentrations were 5% (for olive mill wastewater) and 7% (for orange juice) as indicated by recovery % and the rest cloud point extraction parameters (analyte concentration, concentration factor, and phase volume ratio). A double step CPE with 5% + 5% of Tween 80 recovered up to 94.4% of the total phenols from olive mill wastewater, while a 7% + 7% of Tween 80 recovered up to 72.4% of the total carotenoids from orange juice. Evaluation of the final effects and extraction efficiency of single and double step cloud point extraction shows that double step scheme seems to be preferable in both cases. Finally, phenols and carotenoids recovered by Tween 80 maintained high antiradical activity (DPPH test).

The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina... more The antimicrobial activity of the oil extracted with n-hexane from the seeds of Moringa peregrina was tested against Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Candida albicans, C. tropicalis and C. glabrata. The oil proved effective against all of the tested microorganisms. Standard antibiotics (netilmycin, 5-flucytocine, intraconazole and 7-amino-4-methylcoumarin-3-acetic acid) were used for comparison. The resistance to oxidation of the extracted seed oil was also determined.

The possibility to increase the nutritional value of table olives using polyphenols extracted fro... more The possibility to increase the nutritional value of table olives using polyphenols extracted from olive leaves was studied. Leaves were subjected to extraction using water with proportions of 1%, 5% and 10% of leaves and various temperatures and times (room temperature/24 h, 40 °C/10 min and 70 °C/5 min). The antioxidant activity of extracts was determined using the Rancimat method and their content in oleuropein and hydroxytyrosol was determined by HPLC. The extract with the highest antioxidant activity and polyphenol content (10% ratio of olive leaves extracted at room temperature for 24 h) was used for the treatment of debittered table olives. The treated and untreated olives were subjected to determination of their α-tocopherol, oleuropein and hydroxytyrosol content. A 457% increase was observed for oleuropein and 109% for hydroxytyrosol content after treatment. Sensory evaluation of treated table olives showed an increase in bitterness. However, treated and untreated table olives showed equal overall acceptability and overall preference.

Separations, Apr 28, 2024

ChemEngineering, Mar 1, 2024

Applied sciences, Feb 28, 2024

Applied sciences, Nov 29, 2023

Sustainability, Nov 22, 2023

Horticulturae, Aug 17, 2023

Biomass

The food processing industry is a continuously developing sector that uses innovative technologie... more The food processing industry is a continuously developing sector that uses innovative technologies to efficiently process food products. During processing, food industries generate substantial amounts of by-products in the form of waste materials. This food waste consists of organic matter rich in bioactive compounds, such as polyphenols, carotenoids, and flavonoids. Improper management of food waste can adversely affect both the environment and human health, leading to environmental pollution and the release of greenhouse gas emissions. Thus, proper food waste management has become an urgent global issue. The presence of bioactive compounds (mainly polyphenols, flavonoids, and anthocyanins, but also carotenoids, alkaloids, proteins, lipids, and carbohydrates) in food waste holds the potential to transform them into valuable resources. Several sectors, including food and energy, have recognized food waste as an innovative source. Recently, much emphasis has been placed on optimizing...

Compounds

Crithmum maritimum, commonly known as rock samphire, is a plant species with a long history of us... more Crithmum maritimum, commonly known as rock samphire, is a plant species with a long history of use in traditional medicine and cuisine, especially in the Mediterranean region. Despite its potential therapeutic and commercial applications, the number of studies on this plant species are scanty and sparse. The aim of this study was to optimize the solid–liquid extraction of bioactive compounds from C. maritimum leaves through response surface methodology (RSM) and to comprehensively analyze the resulting extracts. Experimental parameters including liquid-to-solid ratio, solvent composition, extraction time, and temperature were investigated. The results of the RSM revealed a notable variation in the values of the extracted bioactive compounds (polyphenols, carotenoids, and chlorophylls), indicating the selection of optimum extraction conditions. Partial least squares analysis showed that solvent composition and extraction temperature had a significant impact on the extraction of the b...

Applied Sciences

Watermelon (Citrullus lanatus) is a popular fruit worldwide due to its refreshing taste and its h... more Watermelon (Citrullus lanatus) is a popular fruit worldwide due to its refreshing taste and its high water content (92% of its weight). According to the phytochemistry of the plant, carbohydrates, saponins, glycosides, steroids, alkaloids, polyphenols, flavonoids, and tannins can be detected in watermelons. C. lanatus generates by-products and, as such, can be characterized by its seeds and rinds. These by-products’ phytochemicals are nutritious and functional. Watermelon seeds contain many phytochemical compounds with beneficial biological activities, according to numerous scientific studies. This fact promotes watermelon seed consumption and encourages food and pharmaceutical companies to use this innovative ingredient. The watermelon rind has all the nutrients of the pulp and also more antioxidants, minerals, vitamins, and bioactive substances. Numerous studies show that watermelon peel is high in fiber and nutrients and can be used in a variety of culinary products. These residu...

Journal of Applied Research on Medicinal and Aromatic Plants, Mar 1, 2023

Journal of the American Oil Chemists' Society, Aug 11, 2012

On behalf of the open access journal Sustainability (ISSN 2071-1050, IF 3.251), I am pleased to a... more On behalf of the open access journal Sustainability (ISSN 2071-1050, IF 3.251), I am pleased to announce a new Special Issue entitled "Exploring Natural Product Extracts, Food Technology and Functional Foods on the Sustainable Health Perspective". Prof. Dr. Stavros I. Lalas (Department of Food Science & Nutrition, University of Thessaly, Greece) and I are serving as Guest Editors for this issue.

The submission deadline is 30 September 2022 and papers may be submitted immediately or at any point until 30 September 2022, as papers will be published on an ongoing basis. For more information on this Special Issue and submission guidelines, please visit the following page:
https://www.mdpi.com/journal/sustainability/special_issues/natural_product_extracts