Phenolics content and antioxidant capacity of commercial red fruit juices

The content of phenolics: total phenols (TP), flavonoids (TF), anthocyanins (TA) and hydroxicinnamic acid as well as the total antioxidant capacity (TAC) in nine commercial red fruit juices (sour cherry, black currant, red grape) produced in Serbia were evaluated. The total compounds content was measured by spectrophotometric methods, TAC was determined using DPPH assays, and individual anthocyanins and hydroxycinnamic acids was determined using HPLC-DAD methods. Among the examined fruit juices, the black currant juices contained the highest amounts of all groups of the phenolics and exhibited strong antioxidant capacity. The amount of anthocyanins determined by HPLC method ranged from 92.36 to 512.73 mg/L in red grape and black currant juices, respectively. The anthocyanins present in the investigated red fruit juices were derivatives of cyanidin, delphinidin, petunidin, peonidin and malvidin. The predominant phenolic acid was neoclorogenic acid in sour cherry, caffeic acid in black currant, and p-coumaric acid in black grape juices. Generally, the red fruit juices produced in the Serbia are a rich source of the phenolic, which show evident antioxidant capacity

Polyphenol content and antioxidant activity of sour cherries from Serbia

The aim of this study is to evaluate the content of phenolics: the total phenols (TP), flavonoids (TF), anthocyanins (TA), as well as the total antioxidant capacity (TAC) in three sour cherry cultivars (Prunus cerasus L.) introduced to the southeast Serbia climate conditions. Among the researched sour cherries, ‘Oblacinska’ cultivar contained the highest amounts of all groups of phenolics, followed by ‘Cigancica’ > ‘Marela’. A significant difference were observed in the phenolic content among different cultivars and growing seasons (p<0.05), and the phenolic compounds were significantly higher in the growing season 2009. The examined cultivars possess a high antioxidant capacity, and all phenolics of highy correlation with TAC. The following compounds were identified and quantified using HPLC-DAD: 4 anthocyanins, the most abundant of which was cyaniding-3-glucoside in ‘Marela’ and ‘Oblacinska’, and cyanidin-3-glucosylrutinoside in ‘Cigancica’, and 4 hydroxycinnamic acids, the most abundant of which was neochlorogenic acid in all sour cherry cultivars. The growing and ripening process on the tree of sour cherry cv. Oblacinska was evaluated, also. The results showed significant increases in total phenols during the ripening, the total anthocyanins and total antioxidant capacity and 4 quantified anthocyanins, however the neochlorogenic acid decreased during the ripening. The study indicated that the growing and climate conditions in southeast Serbia are convenient for introducing sour cherry cultivars

The correlation of metal content in medicinal plants and their water extracts

The quality of some medicinal plants and their water extracts from South East Serbia is determined on the basis of metal content using atomic absorption spectrometry. The two methods were used for the preparation of water extracts, to examine the impact of the preparation on the content of metals in them. Content of investigated metals in both water extracts is markedly lower then in medicinal plants, but were higher in water extract prepared by method (I), with exception of lead content. The coefficients of extraction for the observed metal can be represented in the following order: Zn > Mn > Pb > Cu > Fe. Correlation coefficients between the metal concentration in the extract and total metal content in plant material vary in the range from 0.6369 to 0.9956. This indicates need the plants to be collected and grown in the unpolluted area and to examine the metal content. The content of heavy metals in the investigated medicinal plants and their water extracts is below the maximum allowable values, so they are safe to use

Application of oxidation processes in the purification of wastewaters from phenolic compounds

Natural phenolic compounds are significant component of the human diet, as they are present in fruits and vegetables, and they have very important biological activity in the living organisms. Because of their structure, they are subject of numerous oxidation processes, such as autoxidation, but are easily to oxidize in presence of various oxidizing agents and enzymes. Many authors have been investigating phenolic oxidation processes, and have successfully identified their pathways and a significant number of intermediates and products generated by these processes. Also, particular attention has been made to the effects of these processes on food quality and other biological processes in living organisms. Phenols are persistent pollutants of water systems from various agricultural activities and industrial wastewater discharges. It is known that the presence of phenolic compounds in water supplies and industrial effluents directly affects natural processes in the environment due to their toxicity and natural ability to decompose. This property, to easily oxidize and, as a result of it, to mineralize, is practically useful for the treatment of the wastewaters, so it is of global concern to manage the best technology to remove phenols and other organic pollutants, assisted with the oxidation processes. In the aspect of treatment of wastewaters polluted with phenols, we reviewed oxidative processes such as autoxidation, enzyme-catalyzed oxidation, photo-oxidation, electrochemical oxidation and oxidation by Fenton's reagent and, based on the literature data, we presented advantages and disadvantages of these processes compared to each other. © 2020 Editura Academiei Romane. All rights reserved

TOTAL PHENOL, FLAVONOID AND HEAVY METAL CONTENT AND ANTIOXIDANT ACTIVITY OF SOLVENT EXTRACTS OF ORIGANUM VULGARE L.

Water, ethanol and water-ethanol (1:1, v/v) extractsofthe (ethno)pharmacologically valued plant species Origanum vulgare L. were studied for the total phenol (TP), flavonoid (TF) and heavy metal (HM; Zn, Fe, Cu, and Mn) content. All three prepared extracts contained a rather high amount of phenolics (23.6-75.2 mg gallic acid equivalents/g) and a low amount of flavonoid compounds (1.0-2.1 mg quercetin equivalents/g). In addition, the content of (toxic) metals (Zn, Fe, Cu, and Mn) was low (0.4-153 mg/kg). Antioxidant potential of the extracts was determined using a DPPH assay and correlated with TP, TF and HM. According to the obtained results, the high observed radical scavenging activity (75.1-93.8%) is mostly related to the presence of flavonoid and other phenolic compounds. SADRŽAJ UKUPNIH FENOLA, FLAVONOIDA I TEŠKIH METALA, KAO I ANTIOKISIDATIVNA AKTIVNOST EKSTRAKATA BILJNE VRSTE ORIGANUM VULGARE L. U ovom radu su izloženi rezultati ispitivanja sadržaja ukupnih fenola (TP), flavonoida (TF) i teških metala (HM; Zn, Fe, Cu i Mn) u vodenom, etanolnom i vodeno-etanolnom (1:1, v/v) ekstraktu (etno)farmakološki cenjene biljne vrste Origanum vulgare L. U svim ispitivanim ekstraktima  je utvrđeno prisustvo relativno visoke koncentracije fenolnih jedinjenja (23,6-75,2 mg ekvivalenata galne kiseline/g) i niske koncentracije flavonoida (1,0-2,1 mg ekvivalenata kvercetina/g). Pored toga, sadržaj (toksičnih) metala (Zn, Fe, Cu i Mn) je bio relativno nizak (0,4-153 mg/kg). Antioksidativni potencijal ispitivanih ekstrakata je određen DPPH metodom i korelisan sa TP, TF i HM. Na osnovu dobijenih rezultata, jaka antioksidativna aktivnost (75,1-93,8%) ekstrakata je uglavnom posledica prisustva flavonoida i drugih fenolnih jedinjenja

Removal of cationic pollutants from water by xanthated corn cob: optimization, kinetics, thermodynamics, and prediction of purification process

The removal of Cr(III) ions and methylene blue (MB) from aqueous solutions by xanthated corn cob (xCC) in batch conditions was investigated. The sorption capacity of xCC strongly depended of the pH, and increase when the pH rises. The kinetics was well fitted by pseudo-second order and Chrastil’s model. Sorption of Cr(III) ions and MB on xCC was rapid during the first 20 min of contact time and, thereafter, the biosorption rate decrease gradually until reaching equilibrium. The maximum sorption capacity of 17.13 and 83.89 mg g-1 for Cr(III) ions and MB, respectively was obtained at 40 °C, pH 5 and sorbent dose 4 g dm-3 for removal of Cr(III) ions and 1 g dm-3 for removal of MB. The prediction of purification process was successfully carried out and the verification of theoretically calculated amounts of sorbent was confirmed by using packed-bed column laboratory system with recirculation of the aqueous phase. The wastewater from chrome plating industry was successfully purified, i.e. after 40 min concentration of Cr(III) ions was decreased lower than 0.1 mg dm-3. Also, removal of MB from the river water was successfully carried out and after 40 min removal efficiency was about 94 %

Rapid and Reliable HPLC Method for the Determination of Vitamin C in Pharmaceutical Samples

Purpose: To develop and validate an accurate, sensitive and reproducible high performance liquid chromatographic (HPLC) method for the quantitation of vitamin C in pharmaceutical samples. Method: The drug and the standard were eluted from Superspher RP-18 (250 mm x 4.6 mm, 10µm particle size) at 20 0C. The mobile phase was prepared by carefully adding acetic acid (500 ml) to 1.5g of 1-hexanesulfonic acid sodium salt and mixing well (pH 2.6). The flow rate was 0.7 mL min-1. UV detector, set at 280 nm, was used to monitor the effluent. Results: Each analysis required no longer than 4 min. The limit of quantitation was 1.95 µg mL-1 . Recovery (%) for different concentrations ranged from 99.58 to 101.93. Conclusion: The simplicity of this low-cost, rapid technique and its high specificity to ascorbic acid, even in the presence of a variety of excipients, demonstrate that this HPLC method would be particularly suitable for the determination of ascorbic acid in the investigated preparations as well as other similar pharmaceutical/veterinary formulations without prior sample preparation

Effects of acutely applied methionine on plasma oxidative stress markers and AchE activity in rat cardiac and brain tissue

Second Joint Meeting of Slovak and Serbian Physiological Societies "Physiology without frontiers" : May 15-18, 2016, Smolenice Castle, Bratislava, Slovakia

Determination of Benzalkonium Chloride in Nasal Drops by High-Performance Liquid Chromatography

A high-performance liquid chromatography (HPLC) system was used in the reversed phase mode for the determination of benzalkonium chloride (BKC) in nosal drops. A Chromolit RP-18e, 100 x 4.6, (UM6077/035) column was used at 40 °C. The mobile phase, optimized through an experimental design, was a 70:30 (v/v) mixture of 0.057M Na-heksansulphonate potassium, dihydrogen orthophosphate buffer (pH 2.9) and acetonitrile, pumped at a flow rate of 1.75 mL/min at maintaining column temperature at 40 °C. Maximum UV detection was achieved at 215 nm. The method was validated in terms of selectivity, linearity, repeatability, precision and accuracy. The method was successfully applied for the determination of BKC in a pharmaceutical formulation of nasal drop solution without any interference from common excipients and drug substance. All the validation parameters were within the acceptance range, concordant to ICH guidelines

Malva sylvestris l. Petals extracts: Composition, antioxidant activity and effect on micronucleus distribution in human lymphocyte

The contents of phenols, flavonoids anthocyans and antioxidant activity of the water (WE), methanol (ME) and methanol-water (MWE) (50/50, v/v) extracts of M. sylvestris fresh and dry petals were determined. Further, for all above mentioned extracts, in vitro effect of the frequency of micronuclei (MN) on peripheral human lymphocytes was evaluated using cytochalasin-B micronucleus (CBMN) assay. Total phenol content (mg of gallic acid equivalent/g of petals) varied from 13.20 (WE) to 29.20 (ME) of fresh petals and for dry petals from 80 (WE) to 142 (ME). The content of flavonoids (mg of catechin equivalent /g of petals) ranged from 47.50 (WE) to 101.20 (ME) of fresh petals and for dry petals from 439 (WE) to 814 (ME). The anthocyans content (mg of cyanidin-3-O-glucoside/g of petals) ranged from 0.40 (WE) to 0.72 (ME) of fresh petals and for dry petals from 3.13 (WE) to 6.16 (ME). All extracts showed high antioxidant activity (more than 67%). ME of fresh petals showed a greater decrease in the frequency of MN (from 23.9 to 29.3%) in all tested concentrations (0.5; 1.0 and 2.0 µg/ml) compared to standard radio of protectant to Amifostine (20.8%). © 2017, Scibulcom Ltd. All rights reserved