Olga Gortzi

• BChem, MSc, PhD
• Professor at University of Thessaly

Microalgae have emerged as a valuable source of essential nutrients and bioactive compounds, such as proteins, polyphenols, and polysaccharides, which are critical for overall health. Recent research has demonstrated the therapeutic potential of microalgae in addressing a variety of health conditions, including inflammation, oxidative stress, Type...

Daily, more and more people consume snack bars that may have an impact on blood glucose levels. The aim of the present study was to compare the acute effects of a common snack and a plant-based snack bar (PB) that was developed at the University of Thessaly as a functional diabetic snack on blood glucose and insulin in patients with type 2 diabetes...

According to the US Department of Agriculture, more than 4000 types of beans are cultivated in the United States and worldwide; nevertheless, the demand for beans continues to rise. To some extent, diet can treat inflammation and consequently reduce the chances of developing comorbidities, such as diabetes. A diet based on alternative plant protein...

Diabetes is a metabolic disease that is a major health problem globally. Dietary interventions contribute to the management of the disease and the improvement in patients’ quality of life. The aim of the present study was to assess the effects of a nutrition and lifestyle education intervention on a sample of patients with diabetes. The duration of...

Nutrition and dietetic care span various life stages, addressing nutritional needs and exploring factors that shape dietary habits. Globally, an alarming disproportion in food resource distribution, coupled with substandard nutritional intake, underscores profound implications for oral health. This is evident in the facilitation of dental caries de...

In this study, the objective was to ascertain the optimal extraction method for the recovery of polyphenols from two peach cultivars, namely ‘Andross’ and ‘Everts’, at unripe and ripe stages. Two extraction techniques were explored: conventional extraction and cloud-point extraction (CPE), utilizing various solvents, including water, ethanol, 60% e...

This study aimed to assess the feasibility of employing cloud point extraction (CPE) as an efficient way of extracting polyphenols from peach waste (PW). Four distinct food-grade surfactants (Genapol X-080, PEG 8000, Tween 80, and lecithin) were evaluated at concentrations ranging from 2–10% w/v to determine the efficiency of the technique in two s...

Citation: Dimopoulou, M.; Vareltzis, P.; Floros, S.; Androutsos, O.; Bargiota, A.; Gortzi, O. Development of a Functional Acceptable Diabetic and Plant-Based Snack Bar Using Mushroom (Coprinus comatus) Powder. Foods 2023, 12, 2702. Abstract: Consumers' growing concern about health and well-being has led to increased interest in functional foods. Th...

The objective of this study was to investigate the feasibility of using Cloud Point Extraction (CPE) to isolate natural antioxidants (polyphenols) from apricot cannery waste (ACW). Four different food-grade surfactants (Genapol X-080, PEG 8000, Tween 80, and Lecithin) were tested at varying concentrations to evaluate the effectiveness of the techni...

This study aimed to assess the impact of genotype, location, and type of cultivation (organic) on the nutrient and anti-nutrient components of seven large-seeded bean (Phaseolus vulgaris L.) populations. All genotypes were cultivated during 2014 and 2015 in randomized complete block (RCB) experimental designs in three areas of the Prespa region (Pi...

Oxidative damages are responsible for many adverse health effects and food deterioration. The use of antioxidant substances is well renowned, and as such, much emphasis is placed on their use. Since synthetic antioxidants exhibit potential adverse effects, plant-derived antioxidants are a preferable solution. Despite the myriads of plants that exis...

Athletes often consume functional beverages in order to improve performance and reduce oxidative stress caused by high-intensity exercise. The present study aimed to evaluate the antioxidant and antibacterial properties of a functional sports beverage formulation. The beverage's antioxidant effects were assessed on human mesenchymal stem cells (MSC...

In this study, the essential oil (EO) from the peel of the Greek citrus hybrid Citrus sinensis cv New Hall - Citrus aurantium was studied in terms of its antimicrobial properties as well as its effect on Saccharomyces cerevisiae. According to the analysis of the EO, 48 compounds are contained in it, with the main compounds being limonene, β-pinene,...

The extraction of olive oil produces significant residual olive-mill wastewater (OMW). The composition of OMW varies according to the type of olive, the fruit’s ripeness level, and the extraction method (traditional one-pressing system or continuous systems based on centrifugation of the olive pulp). In olive-producing countries, OMW is important f...

The traditional extraction methods used to recover natural antioxidants from food industry wastes involve significant amounts of hazardous solvents. A viable alternative is the use of non-toxic surfactants to remove organic compounds from wastes at temperatures above the cloud point. Cloud point extraction has only recently begun to be used to reco...

Mushrooms are considered to be functional foods with high nutritional, culinary, and pharmacological values, and there has been an increase in their consumption, both through the diet and in the form of dietary supplements. The present study aimed to briefly review the nutritional composition and biological properties of sixteen mushroom species, a...

The growing interest in foods that can be beneficial to human health is bringing into focus some products that have been used locally for centuries but have recently gained worldwide attention. One of these foods is pumpkin seed oil, which has been used in culinary and traditional medicine, but recent data also show its use in the pharmaceutical an...

Consumers tend to perceive organic foods as more nutritious and safer in comparison to conventional, due to the perception that organic food is eco- and animal-friendly. Since fatty acids and fat-soluble vitamins in dairy produce are important nutrients, this study aims to assess possible differences in the amount of these components included in or...

Aromatic plants and their essential oils have been used therapeutically for centuries. Μany published scientific studies have described their remarkable healing properties. The antimicrobial activity of plant species, such as Origanum dictamnus, commonly known as “cretan dittany”, Sideritis sp. (Lamiaceae), Cistus creticus (Cistaceae), and Pistacia...

Mastic gum is a resinous sap produced by Pistacia lentiscus growing in the island of Chios (Greece) and has been recognized since Antiquity for its distinctive aroma as well as medical properties (antimicrobial, antioxidant, anti-inflammatory ones). The oral absorption of Chios Mastic gum (an insoluble polymer of poly-β-myrcene is among the most ab...

Cynara cardunculus L. is a plant of the Mediterranean basin, known since antiquity as a food and for its therapeutic properties. The needs of the 21st century for the utilization of agricultural waste has led to the study of the seed oil of a Greek cultivar of Cynara cardunculus (GCCC) as potential nutritional oil, as large amounts of cardoon seeds...

Cynara cardunculus (artichoke) is a perennial plant of the Mediterranean basin, known since antiquity as food and for its therapeutic properties. Cynara is a relatively small genus with two cultivated species and one wild one. Recently, successful efforts have been made to cultivate wild cardoon and monetise it as a bioenergy crop. In this study, t...

Vitamin A (VA) is an essential nutrient needed in small amounts by humans and supports a wide range of biological actions. Retinol, the most common and most biologically active form of VA has also been found to inhibit peroxidation processes in membranes and it has been widely used as an ingredient with pharmaceutical and nutritional applications....

Food safety in the catering sector of hospitals and other health care units is a very sensitive issue and can be a challenge due to several factors. Patients are particularly susceptible to foodborne illnesses because of disease, medication, malnutrition, or because their immune system is compromised as a result of age, infection or pregnancy. At t...

Carotenoids are powerful natural antioxidants that can easily degrade and are almost insoluble in water. Their incorporation into microemulsions (MEs) can solve these problems. In this study, ethanol extracts (prepared using different protocols) of Capsicum annuum L. (green and red), Moringa oleifera L. leaves, and their mixtures [Red Pepper/M. ole...

Skin is considered to be the largest and fastest-growing organ in Human body and plays an important role in providing protection from pathogens and environmental factors. Due to its large surface area, skin is susceptible to a variety of conditions including acne, dermatitis, eczema, psoriasis, rashes, cellulitis and rosacea. External factors such...

The e- Food science is an Erasmus+ project on the design, development and pilot testing of freely accessible online educational material, for a common group of modules intended for "food science" students. The limitations of existing pedagogical materials and training processes in trainers’ training is that they are not usually customized and adapt...

The e- Food science is an Erasmus+ project which aims to use the potential of Europe's human and social capital originating from higher education institutes and the food industry, in order to develop innovative training material based on selected research findings originated from the participating institutions and also to exchange and transfer know...

Background: Neurodegenerative diseases are increasingly inevitable as the population gets older, with enormous socio-economic costs. The World Health Organization (WHO) has reported that by 2040, neurodegenerative diseases will overtake cancer to become the second leading cause of death, after cardiovascular disease. Objective: Herein, this revi...

Wound healing is a complex process that consists of several phases that range from coagulation, inflammation, accumulation of radical substances, to proliferation, formation of fibrous tissues and collagen, contraction of wound with formation of granulation tissue and scar. Since antiquity, vegetable substances have been used as phytotherapeutic ag...

Wound healing is a complex process that consists of several phases that range from coagulation, inflammation, accumulation of radical substances, to proliferation, formation of fibrous tissues and collagen, contraction of wound with formation of granulation tissue and scar. Since antiquity, vegetable substances have been used as phytotherapeutic ag...

Food safety and hygiene is always a very interesting and timely issue, because it directly affects public health, and demonstrates the cultural level of each state, especially after the constant crises in the food chain. In recent years food crises, have been recorded both at a local and at the international level regarding the safety of meals in h...

Background: At present, much attention has been focused on the beneficial effects of natural products on the human health due to their high efficacy and low adverse effects. Among them, polyphenolic compounds are known as one of the most important and common classes of natural products which possess multiple range of health-promotion effects inclu...

The complexes formed by two polyphenols, trans-Ferulic acid (FA) and Gallic acid (GA) with 2-hydroxypropyl-b-cyclodextrin (HPβCD), by the spray-drying method, were studied. Encapsulation-efficiencies (EE) of the complexes prepared were evaluated by HPLC. In the case of co-encapsulation, the EE of GA was lowered, whereas that of FA was almost stable...

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...

Chemical composition, antioxidant and antimicrobial activity of thirty two (32) selected Mediterranean propolis extracts from mainland Greece, Greek islands, Cyprus, Croatia, and Algeria were determined. Chemo-geographical patterns within Mediterranean propolis were further analyzed by chemometrics. Knowledge of propolis composition, which depends...

Consumers are showing an increasing interest in obtaining additional benefits from food. Biofunctional foods have emerged on the market as a possible solution for such demands. Their composition and biological activity are such that - beyond their inherent nutritional value - promote beneficial effects on one or more target functions/organs in the...

Abstract The development and evaluation of a phospholipidsterol- protein membrane resembling system containing β- lactoglobulin (β-Lg) has been studied. Liposomes have been successfully employed for the protection, controlled release and site specific delivery of sensitive molecules, such as enzymes and vitamins. β-Lg (the major whey protein of rum...

The extraction of polyphenols from wood chips into a wine model system was described using kinetics, over a period of 20 days. The wood chips tested were made from oak (Quercus alba), false acacia (Robinia pseudoacacia) and cherry (Prunus avium) wood. Kinetics were established using nonlinear regression and the leaching of polyphenols into the liqu...

The development and evaluation of a phospholipid-sterol-protein membrane resembling system containing β-lactoglobulin (β-Lg) has been studied. Liposomes have been successfully employed for the protection, controlled release and site specific delivery of sensitive molecules, such as enzymes and vitamins. β-Lg (the major whey protein of ruminant spec...

Nine phenolic compounds, such as cis-/trans-p-coumaric acid, cis-/trans-p-coumaric acid methyl ester, glucose ester of cis-/trans-p-coumaric acid, caffeic acid methyl ester, kaempferol 7-O-beta-D-glucoside and kaempferol 3-O-beta-D-glucoside, were isolated from Lavatera trimestris flowers by chromatographic techniques and their structures were eluc...

Enzyme-linked immunosorbent assay (ELISA) is widely used in the food industry for detecting aflatoxin M1 (AFM1) in milk. The purpose of this survey was to compare the performance of three ELISA kits for the determination of AFM1 in goat milk by evaluating specific performance parameters such as precision, accuracy, repeatability and specificity, wi...

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...

Abstract Vitamin E (VE) or α-tocopherol is the major fat-soluble antioxidant in the human body. It is a sensitive, easily oxidized in the air, molecule, so it must be protected from pro-oxidant elements which could affect its physiological benefits. Encapsulation constitutes a promising approach to maintain VE native properties over time and increa...

Mushrooms are a popular food, due to their unique flavour and taste, nutritional properties and health benefits. Among all edible mushrooms, the genus Tuber is the most well known for truffles, as it has a number of distinctive characteristics and high economic value [1]. Among Tuber species, winter black truffles (Tuber melanosporum) and black sum...

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...

The chemical composition of the essential oil obtained by steam distillation from the wood of P. heldreichii, collected from north Greece area was determined by GC and GC/MS for the first time. Forty constituents (corresponding to 96.3% of the total weight) were identified. The main components were: limonene, cembrene, longifolene, α-pinene, methyl...

This work was dedicated to reporting the full chemical and physical characterisation of Crambe abyssi-nica 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 rela...

Propolis (bee glue) is a resinous material that bees collect from plants to use it as a protective agent to prevent the spread of microbial in their hives and as construction material. It has been observed that the wide range of biological activities (antimicrobial, antiseptic, antitumor, anti-inflammatory, etc) of propolis depends on its chemical...

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 microor...

Vitamin E (VE) or α-tocopherol is the major fat soluble antioxidant in the human body, since it protects cellular membranes and other lipids against oxidative damage. It reduces the formation of hydroperoxides and delays the initial phase of the oxidative process. Vitamin E is a sensitive, easily oxidized in the air molecule, so must be preserved f...

The effect of the addition of an essential oil (EO) preparation (containing a mixture of natural and nature-identical EO) on the performance of dairy ewes of the Chios breed was investigated. Eighty lactating ewes were allocated into 4 equal groups in a randomized block design, each with 4 replicates of 5 ewes housed in the same pen. The 4 groups w...

Benzimidazoles are veterinary drugs widely used against endoparasites in food-producing animals. Albendazole (ABZ), a benzimidazole, is believed to cause embryotoxicity, teratogenicity and other adverse health effects. This study assessed the residue levels of ABZ and its two major metabolites, the sulfoxide (ABZ-SO) and sulfone (ABZ-SO2), in raw m...

Cloud point extraction (CPE), a promising and simple technique for the separation of organic compounds using surfactants (Genapol X-080 [oligoethylene glycol monoalkyl ether] and PEG 8000 [polyethylene glycol with molecular weight of 8000]), was used to recover polyphenols from wine sludge (wine production waste). The effect of various parameters s...

Because polycyclic aromatic hydrocarbons (PAHs) have been proven to be toxic, mutagenic, and/or carcinogenic, there is widespread interest in analyzing and evaluating exposure to PAHs in atmospheric environments influenced by different emission sources. Because traffic emissions are one of the biggest sources of fine particles, more information on...

The chemical composition of the essential oils from Origanum dictamnus L. (wild and organic cultivated plant) was analysed by GC–MS. Carvacrol, thymol, p-cymene, and γ-terpinene were identified as major constituents and isolated from both samples. The above components were successfully encapsulated in phosphatidyl choline-based liposomes and the po...

The chemical composition of the essential oil from fruits of the Greek citrus hybrid Citrus sinensis cv New Hall – Citrus aurantium was investigated by GC and GC-MS. Forty-four compounds were identified, representing 92.83% of the total oil. Limonene, myrcene, β-pinene, α-pinene and α-terpineol constituted the major components of the oil. The effec...

The possibility of applying cloud point extraction (CPE) using Genapol X-080 as surfactant for the separation of phenolic compounds from olive mill wastewater was examined. The ability of the surfactant to recover individual and mixtures of polyphenols and tocopherols in various concentrations from aqueous solutions was tested before its applicatio...

The volatiles from the aerial parts of edible plants growing in Tanzania, Leucas glabrata, Plectranthus laxiflorus, Salvia nilotica and Vernonia smithiana, were investigated by GC and GC/MS. Thirty-five compounds were identified from L. glabrata, representing 80.4% of the total oil; forty-three from P. laxiflorus (86.7%); twenty-four from S. niloti...

The antioxidant and antimicrobial activity of Myrtus communis extract was determined before and after its encapsulation in liposomes of different composition. Evaluation of the sunflower oil oxidation by the Rancimat stability test and malondialdehyde formation by HPLC were used to measure the antioxidant action in comparison with common commercial...

The effect on induction period and tocopherol content after γ-irradiation onsamples of olive oil and seed oils (sunflower and soybean) was determined. In seed oilsamples 0, 100, 200 and 300 ppm of δ-tocopherol were added before irradiation with 1, 2and 3kGy. The results of induction period showed that, after irradiation, all samplespresented...

The antioxidant and antimicrobial activity of methanol or dichloromethane extracts of O. dictamnus, produced from wild and organic cultivated specimens, were determined. The Rancimat and malondialdehyde (MDA) by HPLC methods were used to measure the antioxidant action, in comparison with that of the common commercial antioxidants butylated hydroxyt...

The chemical composition of essential oil obtained by steam distillation of dried aerial parts of Phlomis bovei De Noé subsp. bovei collected from Algeria, was analyzed by GC and GC/MS. Seventy five constituents (corresponding to 86.37% of the total weight) were identified. The main components were: germacrene D, beta-caryophyllene, beta-bournonene...

The antibacterial property of essential oils is the most widely studied area in human nutrition, food preservation and animal production [1,2]. The chemical composition of the essential oil from Citrus limon (Lemon Greek cultivar) was analysed by GC-MS. Limonene, β-pinene, γ-terpinene, neral and α-terpineol were identified as the main compounds. Th...