Analytical and environmental control of water quality of the Bjelica river

This paper presents the main water quality characteristics of the Bjelica River before and after the discharge of Lučani wastewaters. The objectives of the research included analytical and environmental testing and assessment of the water quality of the Bjelica River before and after the discharge of wastewaters from the Lučani town collector. The results of the physicochemical analysis of major water quality indicators were used. Testing was conducted in July and October 2015, and January, May and July 2016. Assays were performed at the Public Health Institute, Čačak and at the Laboratory of the Faculty of Agronomy, Čačak. The water quality of the river was assessed as moderate ecological status or Class III category of surface waters. The results of the river water quality analysis indicated that the quality of the river water was better before the inflow of effluents from the town collector

Replacing added nitrite by Kitaibelia vitifolia extract in dry fermented Sremska sausage

The effect of replacement of nitrite by the ethanol extract of Kitaibelia vitifolia on the microbiological safety and oxidative stability of dry fermented Sremska sausages (SS) was investigated. Spices and nitrite salt were added to the control group - batch (B I). Modified nitrite-free formulations of SS were produced with the addition of two different amounts of plant extracts (360 mL per 20 kg of fillings in B II and 600 mL per 20 kg of fillings in B III). The larger addition of the herb extract revealed strong antimicrobial activity, when Minimum Inhibitory Concentrations were determined for 8 microbial strains by microdilution method. The results revealed the highest susceptibility of Escherichia coli and Proteus mirabilis. DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity showed the strongest antioxidant activity in non-vacuumed and vacuumed SS samples obtained from B III, enriched with the larger amount of the herb extract

Ecological Preferences and Diversity of Essential Oil Composition in Endangered Wild-Growing Populations of <i>Sideritis sipylea</i> Boiss. (Lamiaceae) of the East Aegean Islands (Greece): Evidencing Antioxidant Potential, Antimicrobial and Cytotoxic Activities

Plants from the genus Sideritis (Lamiaceae) have been widely used in folk medicine for a long time and consequently are a focus of the scientific community. Despite this interest, explicit data about the essential oils (EOs) of the Endangered Sideritis sipylea have not been readily available to date. In this study, we investigated the ecological preferences of Greek S. sipylea and the chemical composition of the essential oils of wild-growing S. sipylea populations from two Greek islands (S1: Samos, S2: Lesvos); we explored concomitant associations with environmental factors; and we assessed their (i) antioxidant potential (two tests), (ii) antimicrobial activity against six microbial and two fungal strains, and (iii) cytotoxic effect in two human and one murine cell lines. We compiled an ecological profile in R based on all known Greek localities of S. sipylea, outlining for the first time its preferences regarding temperature (3.48 ± 1.53 °C to 30.70 ± 1.11 °C) and the precipitation regimes (5.92 ± 2.33 mm to 136 ± 11.43 mm) shaping its natural occurrence in the wild. The chemical analysis (42 compounds in total) confirmed the domination of monoterpene hydrocarbons in both samples (with quantitative and qualitative differences) and identified 12 new constituents reported in S. sipylea for the first time (e.g., Bicyclogermacrene and Cumacrene). Dominant compounds in S1 (39 constituents) were β-Myrcene (20.4%) followed by β-caryophyllene (11.8%), bicyclogermacrene (7.1%), β-pinene (6.3%), carvacrol (6.2%) and α-terpinene (6.1%), whereas in S2 (26 constituents) the main ones were α-pinene (37.3%), β-pinene (15.1%) and sabinene (12.1%), followed by β-caryophyllene (5.6%) and bicyclogermacrene (5.5%). The strong antioxidant capacity and cytotoxic activity of S. sipylea EOs are reported herein for the first time, while new insight is provided regarding their effect on bacterial and fungal strains (four ones originally tested herein). The biological activity analysis demonstrated variation among samples, with S2 being more potent than S1. Altogether, the results of the present study demonstrate the high biological potential of S. sipylea EOs with an interesting antioxidant capacity and antimicrobial and cytotoxic effects and reveal associations of natural chemodiversity with climatic factors

Evaluation of Antimicrobial Activity of <i>Kitaibelia vitifolia</i> Extract against Proven Antibiotic-Susceptible and Multidrug-Resistant (MDR) Strains of Bacteria of Clinical Origin

The goal of the present research was to screen the antimicrobial activity of an ethanolic extract of Kitaibelia vitifolia against 30 multidrug-resistant (MDR) bacterial strains isolated from healthcare-associated infections. Minimum inhibitory concentrations (MICs) of the samples against the tested bacteria were determined using the microdilution method. MDR bacterial strains were characterized using standard biochemical tests and the commercial identification systems API 20 NE and API 20 E as: Klebsiella spp. (18 isolates—I); methicillin-resistant Staphylococcus aureus (MRSA)—3; Acinetobacter spp.—3; Pseudomonas aeruginosa—5; vancomycin-resistant Enterococcus (VRE)—1. The sensitivity of isolated bacterial strains was determined using the disc diffusion method against 25 commonly used antibiotics. The highest level of sensitivity to K. vitifolia extract was confirmed in 88.89% of Klebsiella spp. isolates, E. coli ATCC 25922, two strains of MRSA (1726, 1063), Acinetobacter spp. strain 1578, and VRE strain 30, like Enterococcus faecalis ATCC 29212 (MIC =Acinetobacter spp. (strains 1577 and 6401), where the highest values for MICs were noted (1250 μg/mL). The results indicate that the extract of K. vitifolia could be a possible source for creating new, efficient, and effective natural medicines for combat against MDR strains of bacteria

Free radical scavenging activity, total phenolic and flavonoid contents of mulberry (Morus spp. L., Moraceae) extracts

Mulberry (Morus spp. L., Moraceae) fruits, leaves, bark and branch have been used in traditional medicine as diuretic, hypoglycemic and hypotensive. The mechanism of their effects is correlated with the content of active components. Objective of this work was to evaluate and compare antioxidant properties of different extracts of two Morus species growing in Serbia: Morus alba L. (white mulberry) and Morus nigra L. (black mulberry). Potential antioxidant activity, content of antioxidant compounds (phenolics and flavonoids) and radical scavenging capacity, tested by DPPH method, were evaluated. The phenolic and flavonoid composition of different Morus extracts was determined by the HPLC method. The extracts prepared from fruits, leaves and roots of M. alba and M. nigra exhibited different characteristics. The highest extraction yield was achieved by M. alba leaves extraction (23.40%). M. nigra roots extract shown the highest total phenolics (186.30 mg CAE/g), while highest total flavonoids content (67.37 mg RE/g) was determined for M. nigra leaves extracts. In addition, black mulberry leaves extracts with the highest antioxidant activity had the highest phenolic acids contents. The dominant phenolic components in the samples were rutin and chlorogenic acid. All investigated mulberry dry extracts shown high content of phenolic compounds and significant antioxidant activity. This work contributes to knowledge of the antioxidant properties of Morus species. The obtained results may be useful in the evaluation of new dietary supplements and food products

Antioxidant activity of ultrasonic extracts of leek Allium porrum L.

This study was aimed at evaluating the antioxidant activity and efficacy of the ethanolic extract of the ultrasonic extracts of leek Allium porrum L. Ethanolic (50%; v/v) extracts of edible leek parts (stem and leaf) were prepared by ultrasound-assisted extraction, which was followed by evaluation of total phenols, flavonoids and antioxidant activity. Total phenols were determined using the modified Folin-Ciocalteu method. Antioxidant activity was assessed by scavenging the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). The results of antioxidant activity were compared with control antioxidants: vitamin C and BHT. The higher content of phenols (69.46 mg GAE/g dry extract) and flavonoids (33.53 mg CE/g dry extract) was found in the ethanolic extract of leek stem. The measured values of IC50 were 98.90 g/ml and 61.05 g/ml for the ethanolic extract of leek leaf and stem, respectively

A Study on the Ethanolic Extract of Onosma aucheriana. Biological and toxicological evaluation

This research studies the antioxidant activity and efficacy of the ethanolic extract of the plant species Onosma aucheriana DC. This plant growing wild in Serbia, in inhibiting the development of selected fungi and bacteria. The most sensitive to the ethanolic extracts were bacteria B. subtilis and S. aureus (MIC = 15.62 mg/mL), while the fungi, A. niger (MIC = 15.62 mg/mL) showed the highest susceptibility. Total phenolic, flavonoid, condensed tannin and gallotannin contents were 90.26 mg GA/g, 35.24 mg RU/g, 74.65 mg GA/g and 31.74 mg GA/g, respectively. Phenolic compounds are found as dominant in the extract of rosmarinic acid. Total antioxidant capacity was 78.45 mg AA/g. IC50 values were determined for each measurement: 21.45 mg/mL for DPPH free radical scavenging activity, 36.46 mg/mL for inhibitory activity against lipid peroxidation, 99.11 mg/mL for hydroxyl radical scavenging activity and 45.91 mg/mL for chelating ability. A potent inhibitor of cell growth to all three cell lines (Hep2c, RD, L2OB) is the ethanol extract of plant species O. aucheriana . Results of Allium anaphase-telophase genotoxicity assay revealed that the ethanolic extract of O. aucheriana at concentrations of 62.5 mg/mL does not produce toxic or genotoxic effects.Revista de Chimie (2016), 67(12): 2511-251

HPLC analysis, antimicrobial and antioxidant activities of Daphne cneorum L.

The present study describes in vitro antimicrobial and antioxidant activities of the methanol extracts which were obtained from the leaves and twigs of the plant Daphne cneorum L. The antimicrobial activity of these extracts was tested against human pathogenic microorganisms using a minimum inhibitory concentration (MIC) values. Total phenolics and flavonoids, as well as the antioxidant activity of the extracts were determined. The two tested extracts showed good antimicrobial and antioxidant activities. The results of a high performance liquid chromatographic (HPLC) method showed that 7,8-dihydroxycoumarin is one of the most abundant secondary metabolite in the tested extracts. The results of this study clearly indicated that the extracts of D. cneorum could be used as a potential source of natural antioxidant and antimicrobial agents

Phytochemical screening and biological activity of extracts of plant species Halacsya sendtneri (Boiss.) Dörfl.

This study is aimed at examining total polyphenol, flavonoid, gallotannin and condensed tannins content in acetone, chloroform, ethyl acetate and petroleum ether extracts of Halacsya sendtneri (Boiss.) Dörfl., their antimicrobial and antioxidant activities, as well as identifying and quantifying the phenolic components. The antioxidant activity is consistent with the results of total quantity of phenolic compound. The results showed that the acetone extract of plant species Halascya sendtneri (Boiss.) Dörfl. possessed the highest antioxidant activity. IC50 values were determined: 9.45��1.55 μg/mL for DPPH free radical scavenging activity, 13.46±1.68 μg/mL for inhibitory activity against lipid peroxidation, 59.11±0.83 μg/mL for hydroxyl radical scavenging activity and 27.91±0.88 μg/mL for ferrous ion chelating ability. The antimicrobial activity was tested using broth dilution procedure for determination of the minimum inhibitory concentration (MIC). The MICs were determined for 8 selected indicator strains. All of the extracts showed strong to moderate strong antimicrobial activity. The phenolic composition of Halacsya sendtneri extracts was determined by the HPLC method. The dominant phenolic compound in acetone, chloroform and ethyl acetate extract is rosmarinic acid. Ethyl acetate extract was also abundant in p-hydroxybenzoic acid and ferulic acid. The main compounds in petrol ether extract were chlorogenic acid and quercetin

The influence of the extraction temperature on polyphenolic profiles and bioactivity of chamomile (Matricaria chamomilla L.) subcritical water extracts

© 2018 The main goal of this research was to determine the relationship among chemical structure, bioactivity and temperature of chamomile during subcritical water extraction in isobaric conditions (45 bar) at seven different temperatures (65–210 °C). The influence of temperature on phenolic profiles was defined by UHPLC-HESI-MS/MS. The overall results indicate that the presence of conjugated double bonds, side chains, glucose moiety or ether moiety in molecules influence the efficiency of polyphenols’ extraction in subcritical water. In terms of antioxidant activity, the extracts were the most active towards ABTS radicals (IC 50 = 7.3–16.8 µg/mL), whereby temperature of 150 °C was optimal. On the other hand, the extracts obtained at 115 °C showed highest cytotoxicity. Inhibition of α-amylase and α-glucosidase was the highest at 65 and 85 °C, i.e. 0.51 and 4.13 mmolAE/g, respectively. Activity against tyrosinase was the highest at 210 °C (17.92 mgKAE/g). The data showed that different non-phenolic compounds may also participate in bio-activities of the extracts