Photochemiluminescence Method Research Articles

Development of New Dermato-Cosmetic Therapeutic Formulas with Extracts of Vinca minor L. Plants from the Dobrogea Region.

A new trend in the use of indole alkaloids from natural products is the preparation of topical pharmaceutical formulations with applications in the field of regenerative medicine. These formulations can be characterized through the ease of administration, the proven healing action of indole alkaloids, the protection of skin lesions, and the assurance of oxygen permeability. Based on the numerous benefits that indole compounds extracted from the Vinca minor plant show externally, the purpose of this study was to develop new semi-solid biocomposites for topical application obtained from hydroalcoholic macerates of 40%, 70%, and 96% concentrations from the stems and leaves of the Vinca minor L. plant from the Dobrogea area. A total of 12 pharmaceutical formulations (named P1-P12) were prepared for which the physicochemical properties, pH, thermal stability, spreading capacity, and rheological behavior were determined. The optimal formulas with antioxidant and antimicrobial capacity were evaluated and determined (P3, P4, P9, and P10). Antioxidant activity was elicited using the photochemiluminescence method. The microorganisms used for the evaluation of antimicrobial activity were Gram-positive Staphylococcus aureus (ATCC 25923), Gram-negative Escherichia coli (ATCC 25922), and a fungal species, Candida albicans (ATCC 900288). The study of the rheological profile for the obtained composites revealed Newtonian, pseudoplastic, and thixotropic fluid behaviors. Following determinations using the photochemiluminescence method, the best antioxidant activity was obtained in the P3 and P9 preparations. The results of the antimicrobial analysis confirmed that both the leaves and the stems of the Vinca minor plant represent a valuable source of antibacterial substances, and the biocomposites analyzed may represent an alternative in the realization of new pharmaceutical preparations with topical applications based on hydroalcoholic macerates obtained from the Vinca minor plant.

Xanthophyll pigments dietary supplements administration and retinal health in the context of increasing life expectancy trend.

Medicine faces nowadays the trend of increasing life expectancy of human population, with the resulting increase of degenerative age related diseases prevalence, combined with the risks of less tempered sun radiations environment exposure. Under these circumstances, our work pointed out on evaluating the effect of some xanthophyll pigments dietary supplements, actually widely recommended, for prevention of retinal degenerative damages and for slowing down the progression of such age related changes if they have already occurred. These dietary supplements are already well known for their total antioxidant activity, proven by photochemiluminescence method using Total Antioxidant Capacity in Lipid soluble-substances procedure. The study recruited a number of 120 subjects equally divided on genders. The lot included a first group of 60 patients with comparable ages (all of them over 50 years and divided in 2 segments of age: 50-60 and over 60) and suffering from comparable retinal age-related degenerative abnormalities (mild/medium severity age-related macular degeneration according to Wisconsin Age-Related Maculopathy Grading System), and a second group, considered control, including a similar number of healthy, normal retina subjects belonging to same age and gender categories. There were evaluated at baseline the eye medical status and the retinal risk by specific methods: complete eye check-up, Amsler grid, specific standardized questionnaires focused on visual function and its impact on the quality of current life. Both groups, patients and control, received similar dosages of xanthophyll pigments dietary supplements including lutein and zeaxanthin during 18 months after baseline; at the end of this supplementation period a new evaluation was conducted. In the second part of the research all subjects involved received a new dietary supplement in which the same xanthophylls were enriched with C and E vitamins and oligo-elements Zinc and Copper. At the end of three years duration supplementation, the subjects were reevaluated and the paper presents the conclusions on the matter, pointing on the impact of xanthophyll supplements on visual health. Correlation tests were applied to the complete set of data. Correlation tests have values between -1 and +1. The value -1 represents the negative correlation (reverse proportionality) meanwhile the value +1 represents the positive correlation (direct proportionality). The charts show the curves that are fitting experimental data. The dependence is linear in nature, and the value R2, as it approaches more the value 1, represents a better match with the experimental data (the data are in a percentage of approximately 99% on these straight lines of type y = ax + b). In the charts, there were noted the average values of the scores for healthy control patients with "Control", and the average values of the scores for the patients with existing age related degenerative retinal pathology at baseline with "Patients". The retinal function and the impact of visual condition on health were both evaluated at baseline, 18 months and 36 months after baseline, by visual acuity, ophthalmoscopy fundus examination, Amsler test and by asking the subjects to answer the visual function questionnaires: EQ-5D, NEI-VFQ-25, as measures of health status quality and of the influence on welfare. The study revealed that under supplementation both control healthy subjects and patients with known degenerative retinal pathology included in the 50-60 years of age group evolved almost the same way, leading to the conclusion that administered xanthophyll pigments-based supplements, simple or enriched, managed to slow down the progression of abnormal degenerative vision loss to a rate comparable to physiological aging-related vision loss. It was also observed that intake of xanthophyll pigments dietary supplements preserved the general health condition and maintained relatively constant vision on the entire 36th months follow-up research duration in patients presented with existing age related degenerative retinal pathology at baseline. For healthy subjects, evaluation showed an improvement in results after dietary supplementation, with maintenance of constant vision and a significantly increase of general condition, in a positive sense. For subjects over the age of 60 dietary supplements intake was even more effective compared to younger group in providing better control of degenerative processes.

Determination of Active Ingredients, Mineral Composition and Antioxidant Properties of Hydroalcoholic Macerates of Vinca minor L. Plant from the Dobrogea Area.

In recent decades, new alternative therapies using drugs containing active ingredients of natural origin have been a hot topic for medical research. Based on the confirmed therapeutic potential of the Vinca minor plant, considered in the specialized literature to be of pharmaceutical interest, the purpose of this study is to determine the chemical and mineral composition of the Vinca minor plant grown in the Dobrogea area, with a view to its use in the formulation of dermal preparations. For this purpose, plant materials were collected from the mentioned area and hydroalcoholic macerates of different concentrations were obtained: 40%, 70% and 96% from leaves (F40, F70, F96) and stems (T40, T70, T96) of Vinca minor plant to determine the optimal extraction solvent. The hydroalcoholic macerates were analyzed via the HPLC method for the identification and quantification of the main bioactive compounds, and two methods were used to evaluate their antioxidant properties: the DPPH radical scavenging test and the photochemiluminescence method. HPLC analysis showed the presence of four indole alkaloids: vincamine, 1,2-dehydroaspidospermidine, vincaminoreine and eburnamonine. Vincamine was the alkaloid found in the highest concentration in Vinca leaves (2.459 ± 0.035 mg/100 g d.w.). The antioxidant activity of Vinca minor hydroalcoholic macerates showed values between 737.626-1123.500 mg GAE/100 g d.w (DPPH test) and 77.439-187.817 mg TE/100 g d.w (photochemiluminescence method). The concentrations of toxic metals Cd, Cu, Ni, Pb in dried leaves and stems of Vinca minor, determined by AAS, were below detection limits.

New Oligomeric Dihydrochalcones in the Moss Polytrichum commune: Identification, Isolation, and Antioxidant Activity.

One of the most widespread representatives of mosses in the temperate and boreal latitudes of the Northern Hemisphere is common haircap (Polytrichum commune), which is known as the largest moss in the world and widely used in traditional herbal medicine. Polyphenolic compounds constitute one of the most important groups of biologically active secondary metabolites of P. commune, however, the available information on their chemical composition is still incomplete and contradictory. In the present study, a group of dihydrochalcone polyphenolic derivatives that were not previously found in mosses was isolated from P. commune biomass using pressurized liquid extraction with aqueous acetone. The combination of two-dimensional NMR spectroscopy and high-performance liquid chromatography–high-resolution mass spectrometry allowed for identifying them as 3-hydroxyphloretin oligomers formed through a carbon–carbon bond between phloroglucinol and pyrocatechol moieties (“head-to-tail” coupling), with a polymerization degree of 2–5. The individual compounds isolated by preparative reverse-phase HPLC had a purity of 71 to 97% and demonstrated high radical scavenging activity (17.5–42.5% with respect to Trolox) determined by the photochemiluminescence method. Along with the low toxicity predicted by QSAR/QSTR algorithms, this makes 3-hydroxyphloretin oligomers a promising source for the production of biologically active food additives and pharmaceuticals.

Antioxidant and antibacterial potential of Ulva lactuca species from Romanian Black Sea Coast

Abstract Green algae biomass represents an important natural resource found in marine environments which could offer new applications in the pharmaceutical and cosmeceutical industries. The paper aim was to characterize some fluid extracts of Ulva lactuca L. green macroalgae species, in the Ulvaceae family, from Romanian Black Sea Coast, through physical, chemical and biological methods. For biomedical applications it is important to study how the difference between the marine environment specific conditions, from which they are harvested, can influence the chemical composition of macroalgae. Another important aspect which could affect the bioactive green macroalgae extracts composition, is the influence of applied extraction method. In this way, the less distructive cold maceration method in different solvent concentrations was chosen, according with literature data. The extracts have been studied in order to determine total polyphenols content, total antioxidant capacity by photochemiluminescence method and antibacterial activity. The results emphasized an antioxidant and antibacterial activity of the studied macroalgae extracts, which can be improved in mixture with other bioactive natural substances, in order to obtain new pharmaceutical preparations for topical applications. The valuable obtained results offer the possibility to propose this natural resource for next studies as biomaterial in tissue engineering, wound dressing and drug delivery systems. We consider that Ulva lactuca L. green macroalgae species of Romanian Black Sea Coast, could be an important source of marine bioactive compounds with various uses in the biomedical field.

Comparative antioxidant activity of various ophthalmic product types for artificial tears under different experimental conditions.

Artificial tears or lubricants is a developing category in pharmaceutical research, due to the permanent increasing incidence of dry eye syndrome caused by the extensive use of personal computers and other gadget screens, associated with global warming and pollution. Considering the role of inflammation in dry eye syndrome, characterized by the production of free radicals, it is imperative to determine which elements are more significant in forming an artificial tear more effectively and more comfortably for the eye state and for the quality of life. Thus, the aim of the present study was to examine the evolution of the total antioxidant capacity of some frequently commercialized artificial tears via the photochemiluminescence method, using an antioxidant capacity of lipid soluble substances procedure, prior and subsequent to the exposure of these therapy agents to some physical agents. This is a preliminary research aiming to evaluate the impact of various environmental factors on these ophthalmic products, to be continued by evaluating whether the effectiveness of these products, in terms of objective examination and patient preference and adherence criteria, is impacted by the conditions of use and storage. Thus, the total antioxidant capacity of the evaluated artificial tear samples after UVC irradiation at 254 nm wavelength was studied, in order to investigate whether their status suffered any change in terms of antioxidant potential. In addition to the findings obtained in the study, some recommendations were also made.

Preliminary Data Regarding Polyphenols, Carotenoids and Flavonoids Content Correlated with Antioxidant Activity of some Taraxacum Sp. Fluid Extracts

In the biomedical sciences field of recent years, phytotherapeutic products usage has intensified because they are a safe and sustainable alternative, with less environmentally aggressive molecules that are able to meet therapeutic needs. Mature vegetal product Taraxacum sp., also known as dandelion, has been used for hundreds of years as a traditional remedy for liver, kidney, lung, gastric diseases and even some cancers, due to its anti-inflammatory and antioxidant effects. The aim of this paper was to assess the contents of some bioactive principles and overall antioxidant potential of Taraxacum sp. hydroalcoholic extracts obtained from both plant organs, herba and radix. The vegetal product was collected in the period September-October 2021, from spontaneous flora of South Dobrudja area, Romania. Fresh plant was dried at room temperature on metal sieves, grind to a fine powder and extracted 10% concentration in ethanol 50% and 70% concentrations, using cold maceration and Soxhlet extraction, standard methods, followed by filtration at normal pressure. Obtained hydroalcoholic extracts were analysed by UV-Vis spectrophotometry for determining total carotenoids, flavonoids and total polyphenols content. The total antioxidant capacity was quantified through photochemiluminescence method by comparison with the standard substance used for calibration, Trolox® as tocopherol analogue by ACL (Antioxidant Capacity of Lipid Soluble Substances) procedure using Photochem apparatus, Analytik Jena AG, Germany. Total carotenoids and flavonoids concentration, respectively polyphenols contents, were highest in 70% ethanol extracts, for the two applied extraction methods. Total antioxidant capacity (TEAC) was variable, with increased values in 70% ethanol extracts of both vegetal products, herba and radix. The preliminary valuable obtained results, offer us the support for continuation of the studies regarding the therapeutic activity of Taraxacum sp. from Dobrudja spontaneous flora.

Preliminary Data Regarding Pharmaceutical Forms Type Gels Based on Marine Algae Extracts with Antioxidant Activity

Abstract Particularly interest on herbs and plant extracts is due to their content of active principles with remarkable pharmacological properties. Different vegetal species contain natural antioxidants (polyphenols) used for their dermatological anti-inflammatory and healing activity, justified by their action on free radicals. The aim of this paper was to obtain selected phytopharmaceuticals formulations type gels with an increased antioxidant potential based on a mixture of fluid extracts from seaweeds species in the phylum Chlorophyta, Cladophora vagabunda (L.) C. Hoek, in the family Cladophoraceae, Ulva lactuca (L.) syn. Ulva rigida (L.), in the family Ulvaceae (sea lettuce) and species in the phylum Rhodophyta, Ceramium rubrum C. Agardh, in the famiy Ceramiaceae, frequently presents along the Romanian Black Sea coast. Fluid extracts concentration 10% were obtained using cold maceration extraction method, in solvents ethylic alcohol 40% and 70%. The obtained vegetal extracts were mixed in different ratio and analysed for physico-chemical properties, for the content of total phenols, chlorophylls, cartenoids, flavonoids and antioxidative capacity by photochemiluminescence method (ACL, Analytik Jena AG procedure). The selected mixed fluid extracts with greatest content of polyphenols and antioxidant activity were used for obtaining pharmaceutical forms type gels which were analyzed for the physical-chemical properties appearance, pH, spredability and total antioxidative capacity. Preliminary results emphasized that proposed pharmaceutical forms type gels had an appreciable antioxidant activity correlated with a good stability, an increased polyphenols content and would represent a possible new dermatological anti-inflammatory and healing preparation.

Antioxidant Activity of Some Fluids Extracts of Indigenous Wild Cherry Fruits

Abstract The paper presents un study regarding the comparative total antioxidant capacity of some fluids extracts of the soluble lipid compounds of Cerasus avium (L.) Moench. syn. Prunus avium (L.) var. sylvestris Ser fruits, popular named wild cherry, species undertaken aiming at exploiting the nutrient profiles and promoting the further development of these indigen phytopharmaceutical resources. For analysis, the photo-chemiluminescence method, ACL procedure, Analytik Jena AG, by comparing with the standard Trolox® solution, was used. Wild cherry fruits fluid extracts analyzed emphasize an increased total antioxidative capacity which may be attributed to the high level content of polyphenolic compounds and minerals content which sustains the possibility to use this valuable vegetal product for nutraceutical or comeceutical preparations.

Antioxidant Activity Correlated with Chlorophyll Pigments and Magnesium Content of Some Green Seaweeds

The complex valorification of seaweed biomass represents a highly important resource for the pharmaceutical and dermo-cosmetic industry, supplying raw material for the extraction of bioactive substances such as, polysaccharides, vitamins, sterols, aminoacids, polyphenols and minerals. Marine algae represent an indefatigability resource of therapeutic active principles for diseases treatment of magnesium deficiency. The presence of chlorophyll pigments in the green algae confirms the magnesium existence, as central element in molecular structures. The main green algae, as Ulva lactuca and Enteromorpha intestinalis present on the Romanian Black Sea Coast, belong to Chlorophyta sp. In this paper we present a study of antioxidant activity correlated with magnesium content and chlorophyll pigments of the green algae Enteromorpha intestinalis and Ulva rigida (syn. Ulva lactuca) hydroalcoholic extracts. For chlorophyll pigments determination, the UV-Vis spectrometry was used. Magnesium content had been determined by absorption atomic spectrometry method, using HR-CS- AAS ContraA 700 apparatus, Analytik Jena and for total antioxidant capacity of green algae extracts, the photochemiluminescence method had been applied, using Photochem Analytik Jena apparatus. The comparative studies on two marine green algae extracts confirm the high magnesium content correlated with a high level of total antioxidant capacity for both species. The results obtained emphasize the possibility to enlarge the options to use these natural vegetal resources from Black Sea Coast, in different degenerative diseases therapy.

Carotenoids, Flavonoids, Total Phenolic Compounds Content and Antioxidant Activity of Indigenous Pyracantha coccinea M. Roem. Fruits

Scarlet/red firethorn, Pyracantha coccinea M. Roem., is a common ornamental shrub, commonly cultivated nowadays in Romania and many other countries, in gardens or hedges. The tree has small white flowers and it produces small bright colored berries. The fruit is bitter and astringent, making it inedible when raw. The fruit can be cooked to make jellies, jams, sauces and marmalade. In this study, the Pyracantha coccinea M. Roem fruits from three common cultivars named �Orange Glow�, �Red Column� and �Soleil d�Or�, were collected from different individuals in Constanta city, Romania. Both frozen and dried (80�C) fruits were analyzed for the active principles content such as, carotenoids, flavonoids and total phenolic compounds correlated with antioxidant activity. Carotenoids were determined by acetone extraction and UV-Vis spectrophotometry, flavonoids, by methanol extraction and UV-Vis spectrophotometry and total phenolic, by methanol extraction, Folin-Ciocalteu reaction and UV-Vis spectrophotometry. The total antioxidant capacity was quantified through photochemiluminescence method by comparison with the standard substance used for calibration, Trolox� as tocopherol analogue (ACL procedure) using Photochem apparatus, Analytik Jena AG, Germany. The average carotenoid content in fresh frozen fruits ranged between 278-545 mg/kg (dry weight equivalent), while in dry material 133-203 mg/kg. Total flavonoids averaged 1415-4953 mg/kg in fresh fruits, increasing after heat-drying to 2981-5759 mg/kg. Fresh fruits contained a total amount of phenolic compounds of 11501-21107 mg/kg DW gallic acid equivalent, while dry fruits averaged 5749-8261 mg/kg GAE. Pyracantha coccinea M. Roem. fruits emphasized an increased antioxidant activity correlated with a high content of potentially bioactive compounds, especially of phenolic compounds, both in frozen and heat-dried state. �Red Column� and �Orange Glow� are the most promising varieties of the three cultivars, for potential pharmaceutical applications.

The influence of geographical origin on honey composition studied by Polish and Slovak honeys

Honey composition is mainly affected by botanical origin, however geographical factors as well as beekeeping practice and storage conditions can also influence its quality. The aim of the study was to determine the impact of geographical origin on physicochemical quality and biological activity of honey. For this reason Polish and Slovak varietal honeys, including per each country: 10 multifloral, 5 tilia, 5 rape, 5 acacia and 5 forest were compared according to their physicochemical parameters (free acidity, pH, electrical conductivity, moisture content, and colour intensity), sugar profile, diastase activity, as well as antioxidant activity (DPPH and FRAP tests, as well as photochemiluminescence method). Moreover, total phenolics compounds and flavonoids content were determined. The most significant differences (P < 0.05) between Polish and Slovak counterparts were found for tilia while the lowest for rape honeys. The impact of geographical origin on overall quality of honey was proved by PCA statistical tool.

Evaluation of Antioxidant and Antimicrobial Activity in Relation to Total Phenolic Content of Green Algae from Black Sea

Worldwide, marine algae are known to produce a wide variety of bioactive secondary metabolites and several compounds have been derived from them for the prospective development of novel drugs by the pharmaceutical industry. In this context, Ulva lactuca, Enteromorpha intestinales, and Cladophora vagabunda, isolated from Black Sea coastal waters of Romania, were evaluated for their potential for bioactivity. Extracts of the algae selected for the study were prepared using ethanol. The study presents original results concerning the total phenolic content (TPC), determined by the spectrometric method (Folin-Ciocalteu method) and the individual phenols from each species of seaweed studied were identified by HPLC-DAD techniques. Total antioxidant activity (ACL) was studied by photochemiluminescence method, and antibacterial activity was studied on two strains of bacteria, Escherichia coli ATCC 10536 - gram-negative and Staphylococcus aureus ATCC 6538P - gram-positive. Results indicated that the highest total phenolic content was obtained for Cladophora vagabunda (325.8 mg/100 g f.w.), followed by Ulva lactuca (285.5 mg/100 g f.w.) and the lowest rate was registered by Enteromorpha intestinalis (268.8 mg/100 g f.w.). Through HPLC-DAD techniques, 6 individual phenolic compounds were identified in all analyzed seaweeds. In addition, two other phenolic compounds were identified in lower concentrations in Ulva lactuca, but only one phenolic compound in Enteromorpha intestinalis. The results of this study show that there is a strong correlation between antioxidant activity (ACL), antibacterial activity and total phenolic content (TPC). Antioxidant activity shows the same order as total phenolic content (TPC): Cladophora vagabunda (64.15 nmol/g sample) followed by Ulva lactuca (22.8 nmol/g sample) and Enteromorpha intestinalis (10.4 nmol/g sample). The antibacterial activity recorded in all green seaweeds shows that the inhibition sites are higher on Escherichia coli compared to Staphylococcus aureus.

Evaluation of Antioxidant Capacities and Phenols Composition of Wild and Cultivated Berries

The study presents original results concerning analytical characterization of alcoholic extracts of four wild berries (blueberries, blackberries, red currants and raspberries) and two cultivated berries (black cherries and strawberries). Total and some individual phenols concentrations were determined using molecular absorption spectrometry (modified Folin Ciocalteu method) and HPLC-DAD technique. The measurement of lipid-soluble antioxidant capacity (ACL) was done by photochemiluminescence method using trolox as standard.The highest total phenolic content was registered in blueberries (543.5 mg/100g f.w.), while the lowest was found in raspberries (344.5 mg/100g f.w.).HPLC � DAD analysis indicated the presence of six individual polyphenolic compounds in different concentrations: gallic acid (62.664 - 178.821 mg/100 g f.w); chlorogenic acid (30.152 - 243.923 mg/100g f.w.); 3-O-methyl-gallic acid (2.035 - 4.907 mg/100 g f.w.); caffeic acid (0.401 - 5.664 mg/100 g f.w.); p-coumaric acid (4.252 - 10.806 mg/100 g f.w.) and cinnamic acid (0.665-0.958 mg/100 g f.w.). ACL results showed values between 54.00 and 1152 �mols trolox/100 g f.w.

Antioxidant Activity as Biomarker of Honey Variety.

Honey variety is commonly defined by beekeepers based on nectar flow availability and the only laboratory method to provide verification is the melissopalynological analysis. Therefore, a quick and simple method for accurate assessment of honey variety is still being researched. The aim of the study was to evaluate the antioxidant activity of honey as an indicator of variety through the use of multivariate statistical analysis. Materials for the study consisted of 90 samples of varietal Polish honeys (rape-12, tilia-10, goldenrod-11, dandelion-5, buckwheat-6, multifloral-17, nectar-honeydew-8 and coniferous honeydew-16 and leafy honeydew-5) obtained directly from apiaries. Honeys were investigated in aspect of antioxidant capacity by photochemiluminescence (PCL) methods using standard ACW and ACL kits. As the reference FRAP and DPPH methods were used. The total phenolics content (TPC) was determined through the Folin-Ciocalteu method. The strongest antioxidant activity was found for buckwheat, while the weakest was found for rape honeys regardless of the used method. Results of the used methods were positively correlated (r = 0.42 to 0.94). Analysis conducted by PCL method confirmed that the minor fraction of honey antioxidants exhibits hydrophobic properties. Clear separation of honey varieties using PCA and Clustering method indicate that antioxidant activity can be a useful parameter for determining the botanical origin of honey.

Inhibition studies on α-amylase using isothermal titration calorimetry

Abstract The control of postprandial blood glucose level via the inhibition of α‐amylase is a relevant strategy for the treatment of type 2 diabetes. Several antidiabetic plants are known but there is no information about their α-amylase inhibitory activity. This in vitro study tries to reveal the answer. Hot water extracts of 58 medicinal plants and spices were examined. Activity measurements of human salivary α-amylase (HSαA) on 0.14 m/v % starch substrate was carried out by isothermal titration calorimetry in the presence or absence of plant extracts. Water soluble antioxidant capacity of each extract was measured with photo-chemiluminescence method. Results have confirmed the inhibitory activity of several plant extracts against HsαA. The green tea, cinnamon and allspice, furthermore leaves of blackberry, raspberry and strawberry deserve particular mention (IC50 ≤ 1.2 mg/mL). A few extracts had significant water-soluble antioxidant capacity compared to ascorbic acid and a weak correlation was recognised between the obtained IC50 and antioxidant capacity values. Inhibition of amylases located in digestive system can be reached via daily intake of most active extracts. These plants could be inserted effectively into a diabetic diet as food supplements.

Extractability of Polyphenols from Black Currant, Red Currant and Gooseberry and Their Antioxidant Activity

In this study, we analyzed extracts of Ribes (black currant, red currant and gooseberry) fruits obtained with methanol, methanol 50% and water. For each extract total polyphenol content, total favonoid content and total anthocyanin content was assessed. The antioxidant activity of extracts was evaluated by 1,1-Diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging capacity and by the photo-chemiluminescence (PCL) method. Identifcation and quantifcation of individual phenolic compounds was performed by means of high performance liquid chromatograph coupled with diode array detector (HPLC-DAD) analyses. From each fruit, best extraction of polyphenols was obtained with methanol 50%. In case of red currants and gooseberry there was no signifcant difference in favonoids and anthocyanins extraction rate by the different extraction solvents. For black currants the methanol and methanol 50% extract presented the highest antioxidant activity. For red currants extracts with methanol 50% showed stronger antioxidant activity (IC50 = 5.71 mg/ml for DPPH, IC50 = 1.17 mg/ml for ABTS) than those with methanol or water. In case of gooseberry by the DPPH test the water extract proved to be the most active (IC50 = 5.9 mg/ml). In the PCL test black currants methanol 50% extract was over 6 times more powerful as the ones from red currants. In case of gooseberries, water extract presented the highest antioxidant activity (41.84 μmol AAE/g). In black currant cyanidin-3-glucoside was the major compound. Quercetin 3-O-glucoside was identifed in each sample. From cinnamic acid derivatives neochlorogenic acid was present in black currants in the highest amount (356.33 μg/g).

The Use of the PHOTOCHEM Device in Evaluation of Antioxidant Activity of Polish Honey

Forty samples of varietal Polish honeys were investigated in order to assess their antioxidant capacity by photochemiluminescence (PCL) methods using standard ACW and ACL kits. The reference methods, FRAP and DPPH, were used. The total phenolics content (TPC) by Folin-Ciocalteau method was determined. The antioxidant properties of honeys as well as TPC were mainly dependent on honey botanical origin. The highest phenolic content and antioxidant activity for dark honeys, while the lowest for white honeys, were found. Moreover, the results obtained by used analytical methods were comparable and the best correlation between PCL and FRAP (r > 0.81) and DPPH (r = 0.74) methods was observed. The TPC in honeys was positively correlated with its antioxidant activity measured by PCL (r > 0.76). Used for the first time, PCL assay demonstrated usefulness in determining the antioxidant capacity of honey, divided into water-and lipid-soluble fractions, measured by ACW and ACL kits, respectively.

Determination of Antioxidant Activity of Brandy and Other Aged Beverages by Electrochemical and Photochemiluminescence Methods

The discovery of the impact of antioxidant compounds on health has led to the development of several methods based on different physiochemical processes for quantifying the antioxidant activity of samples. However, when comparing the antioxidant activity of samples, the use of alternative methods may lead to conflicting results. The aim of this study is to evaluate the antioxidant capacity of brandies, old wines and sweet wines by two methods: the first electrochemical method and the second based on photo-induced chemiluminescence, using various statistical approaches: correlation of data, the Bland-Altman test and FREML regression. The results obtained show that these two methods for evaluating antioxidant activity are not comparable. Only no commercial brandy shows statistically similar results, at a probability of 95 %, for the two methods.

Fatty acid composition and antioxidant activity of Antarctic marine sponges of the genus Latrunculia

The fatty acid composition of marine cold-water sponges of genus Latrunculia, namely Latrunculia bocagei Ridley and Dendy, 1886, and Latrunculia biformis Kirkpatrick, 1907, for which no fatty acid data had been previously reported, has been examined. High levels of long-chain fatty acids (C24–30) with high unsaturation levels (mainly polyunsaturation), and high incidence of branched- and odd-chain fatty acids in sponges are suggested to be partially connected with their specific cell membrane requirements to surmount the negative effects of low temperatures and to enable growth in extreme environments. Furthermore, variations in the fatty acid profile at the species level may reflect variations in compositions or quantities of symbiotic microorganisms that commonly represent up to 60 % of the sponge wet weight. The fatty acid compositions of lipid-rich sponge extracts from five Latrunculia specimens dredged from the Bransfield Strait near the Antarctic Peninsula, were obtained using supercritical carbon dioxide and analyzed using gas chromatography–mass spectrometry–flame ionization detection. Furthermore, the antioxidant activities of these extracts were determined using the photochemiluminescent method. Along with common fatty acids, the chemical analyses revealed very long-chain fatty acids (C22, C24). Differences were seen for the fatty acid levels between both species and different specimens of the same species. The observed differences do not seem connected to the habitat depth of the specimen, but rather indicate the variations within the associated microbiome. Furthermore, these sponge extracts showed antioxidant activities, confirming that they contain lipidic compounds that strongly scavenge free radicals.