Total phenolic content and peroxidase activity in Salanova lettuce

Lettuce (Lactuca sativa L.) belongs to a group of leafy vegetables commonly used as a salad in human nutrition. As minimally processed food product, it is an important source of vitamins, minerals and various antioxidative compounds. In our greenhouse experiment, two Salanova let tuce cultivars (‘Aquino‘ RZ- green and ‘Gaugin‘ RZ- red multi-leaf butterhead) were grown in the fertile soil during three successive seasons (autumn, winter and spring). The aim of the study was to examine the effect of different microbiological fertilizers (EM Aktiv, Vital Tricho and combination of EM Aktiv and Vital Tricho), cultivars and growing seasons on the total phenolic content and peroxidase activity. Our results showed that in all seasons red cultivar ‘Gaugin‘ had higher total phenolic content compared to green cultivar ‘Aquino‘. Their highest level was measured in au tumn with fertilizer Vital Tricho (549.14 µg GAE g-1 FW). The elevated phenolic status of red versus green cultivar was further strengthened by its higher level of peroxidase with the highest activity measured in spring with combination of fertilizers EM Aktiv and Vital Tricho (0.43 U mg-1 prot). The higher peroxidase activity and content of UV-absorbing phenolics, as plant-borne substrates of these enzymes, in the red cultivars indicate that the red leaves are better equipped to combat oxidative stress. Consequently, red cultivar ‘Gaugin‘, with increased synthesis of health-promoting antioxidants, could be considered as functional food in human diet

Silicon facilitates manganese phytoextraction by cucumber (Cucumis sativus L.)

The effect of excess nutrient levels of manganese (Mn, 50 and 100 M) on the growth inhibition and the appearance of Mn-toxicity symptoms in the leaves was studied in cucumber plants (Cucumis sativus L. cv. Chinese long). Silicon (Si), when supplied as 1.5 mM silicic acid, clearly decreased symptoms of Mn-toxicity despite approximately the same total Mn content in the leaves. In treated plants, Si improves growth and biomass production compared with that of non Si treated plants. Inert deposition of Si in the leaf cell walls of cucumber (a Si-accumulating species) enhanced cell wall stability. The mechanism of Si protection is proposed to act by Si induced compartmentation of Mn hence increasing Mn2+ -binding sites in the cell wall (e.g. Mn silicate polymers) finally resulting in decreased toxic free Mn within the plant tissue rather than decrease of Mn uptake. These results suggest that Si nutrition can improve the phytoextraction potential of plants due to enhanced metal tolerance in leaf tissue

Does overhead irrigation with salt affect growth, yield, and phenolic content of lentil plants?

Overhead irrigation of lentil plants with salt (100 mM NaCl) did not have any significant impact on plant growth, while chlorophyll content and chlorophyll fluorescence parameter Fv/Fm were affected. Under such poor irrigation water quality, the malondialdehyde content in leaves was increased due to the lipid peroxidation of membranes. In seeds, the total phenolic content (TPC) was correlated to their total antioxidant capacity (TAC). High performance liquid chromatography-mass spectrometry (HPLC-MS) detection showed that flavonoids (catechin, epicatechin, rutin, p-coumaric acid, quercetin, kaempferol, gallic acid and resveratrol) appear to be the compounds with the greatest influence on the TAC values. Catechin is the most abundant phenolic compound in lentil seeds. Overhead irrigation with salt reduced the concentration of almost all phenolic compounds analyzed from lentil seed extracts

Does overhead irrigation with salt affect growth, yield, and phenolic content of lentil plants?

Overhead irrigation of lentil plants with salt (100 mM NaCl) did not have any significant impact on plant growth, while chlorophyll content and chlorophyll fluorescence parameter F-v/F-m were affected. Under such poor irrigation water quality, the malondialdehyde content in leaves was increased due to the lipid peroxidation of membranes. In seeds, the total phenolic content (TPC) was correlated to their total antioxidant capacity (TAC). High performance liquid chromatography-mass spectrometry (HPLC-MS) detection showed that flavonoids (catechin, epicatechin, rutin, p-coumaric acid, quercetin, kaempferol, gallic acid and resveratrol) appear to be the compounds with the greatest influence on the TAC values. Catechin is the most abundant phenolic compound in lentil seeds. Overhead irrigation with salt reduced the concentration of almost all phenolic compounds analyzed from lentil seed extracts

Pomološka i antioksidativna svojstva sorti jagode gajenih u regionu Mačve

In this work pomological properties of strawberry cultivars were studied considering ripening time, physical and chemical fruit traits as quality attribute parameters, as well as total antioxidant capacity and total phenolics as nutritional parameters. The above mentioned parameters were used for screening five strawberry cultivars (Clery, Elsanta, Arosa, Marmolada and Madeleine) grown in Mačva region (Šabac). Investigations were carried out during 2008. on the private strawberry field of 'Libertas' company. The earliest ripening time was recorded in cv Clery (07.05.), and the latest in cv Arosa (22.05.). Cv Arosa expressed the highest values of fruit weight (41,2 g) and fruit dimensions, as well as the highest soluble solids content (8,7 %). Cv Marmolada had the highest amounts of total sugars (6,92 %), inverted sugars (6,13 %) and vitamin C (80,9 mg 100g-1 FW). Besides vitamin C, as a strong antioxidant in strawberries, total phenolic content were also detected in the studied cultivars, achieving the highest values in cvs Elsanta (16,8 mg g-1 FW) and Marmolada (16,5 mg g-1 FW). Consequently, these cultivars expressed the highest fruit antioxidant capacity which is of importance not only for maintaining the nutritional value and sensorial fruit quality, but also because of considerable health benefits. Generally, on the base of most studied parameters for commercial growing in Mačva region, we can recommend cvs. Arosa, Marmolada and Elsanta, as well as cv Clery with regard to earliness.Rad prikazuje rezultate proučavanja pomoloških osobina (vreme zrenja, fizičke i hemijske osobine ploda) i antioksidativnog kapaciteta ploda pet introdukovanih sorti jagode (Marmolada, Arosa, Elsanta, Madlen i Clery) gajenih u regionu Mačve (Šabac). Ispitivanja su izvedena tokom 2008. godine u zasadu jagode koji se nalazi u vlasništvu firme 'Libertas'. Najraniji početak fenofaze zrenja registrovan je kod sorte Clery (07.05.), a najkasniji kod sorte Arosa (22.05.). Sorta Arosa je ispoljila najbolje fizičke osobine ploda, primarno masu ploda (41,2g) i dimenzije, kao i sadržaj rastvorljivih suvih materija (8,7%). Najviše vrednosti sadržaja ukupnih (6,92%) i invertnih šećera (6,13%) registrovane su kod sorte Marmolada, kao i najviši sadržaj vitamina C (80,9 mg 100g-1 sv.m.p.). Pored vitamina C, kao moćnog antioksidanta u plodu jagode, kod ispitivanih sorti je detektovan i sadržaj ukupnih fenola. Najvišim vrednostima odlikuju se sorte Elsanta (16, 8 mg g-1 sv.m.p.) i Marmolada (16,5 mg g-1sv.m.p.), koje su ispoljile i najveći antioksidativni kapacitet ploda, značajan ne samo za očuvanje hranljive vrednosti i senzoričkog kvaliteta ploda, već i sa aspekta zdravstvene korisnosti za ljudski organizam

Нутритивне и биоактивне компоненте у плодовима једнородних и сталнорађајућих сорти јагодe

Поред шећера и витамина, плод јагоде (Fragaria×ananassa Duch) је важан извор и биоактивних једињења, као што су укупни феноли и антоцијани. Ова једињења истовремено дефинишу нутритивни и сензорички квалитет плода. У овим истраживањима испитиване су новије сорте јагоде , које су још увек у фази тестирања, и то три једнородне сорте ('Aprika', 'Sibilla', 'Vivaldi') и три сталнорађајуће сорте ('Albion', 'Capri', 'Irma') у којима су одређене концентрације индивидуалних шећера, органских киселина, витамина Ц, укупних фенола (TPC) и укупних антоцијана (TACY). Од једнородних сорти 'Vivaldi' се издвојила по садржају TACY (24.92 mg Pg-3-g eq/100 g свеже масе (FW)) и витамина Ц (46.7 mg/100 g FW), док је 'Sibilla' била доминантна у садржају глукозе и фруктозе (2.58 и 2.91 g/100 g FW, по редоследу), као и свих органских киселина детектованих помоћу HPLC. Од свих испитиваних параметара, једино је садржај TPC (1.41 mg GAE (gallic acid equivalents)/FW) био повећан код сорте 'Aprika' у односу на друге сорте. Од сталнорађајућих сорти 'Albion' се значајно издваја по високом садржају TACY (12.37 mg Pg-3-g eq/100 g FW) и витамина Ц (48.1 mg/100 g FW), док је 'Capri' била доминантнија у садржају фруктозе и глукозе (5.60 и 6.18 g/100 g FW, по редоследу), већине органских киселина, као и у садржају TPC (0.74 mg GAE/FW). Са аспекта здравствене корисности плода, као перспективне сорте могу се препоручити 'Aprika' од једнородних и 'Capri' од сталнорађајућих сорти

Comparison of field performance and fruit quality among newly released Italian June-bearing strawberry cultivars

The aim of this study was to compare newly released June-bearing strawberry cultivars (‘Quicky’, ‘Sandra’, ‘Lofty’, ‘Nadja’ and ‘Aprica’) in terms of their phenology, vegetative growth, productivity and fruit quality to identify their potential for wider cultivation. A field study was conducted in a strawberry plantation established in July 2020 in double rows on beds covered with black polyethylene foil (Šid, Serbia). The cultivars were evaluated in 2021–2022 for their flowering and ripening time, productivity, plant growth, biometrical and nutritional fruit traits (soluble solids content – SSC, total acids – TAs, vitamin C, total anthocyanins – TACY, total phenolics – TPC and total antioxidant capacity – TAC). The cultivar ‘Quicky’ started to ripen earliest, while ‘Aprica’ was the latest in both experimental years. The number of branch crowns per plant was significantly higher in ‘Sandra’ and ‘Lofty’, whereby ‘Sandra’ had also the highest number of leaves per rosette (41.5) in comparison with the other tested cultivars. The cultivar ‘Aprica’ was superior in terms of productivity (1061 g/plant and 4.67 kg/m2 ), fruit weight (29.9 g) and fruit shape index (1.15). Contrary to this, ‘Nadja’ was the least productive cultivar (608 g/plant and 2.68 kg/m2). The cultivars ‘Lofty’ and ‘Sandra’ showed the highest SSC values and were also characterized by a considerably high level of TPC (1.29 mg GAE eq g-1 FW) and TACY (24.4 mg pg-3-g eq 100 g-1 FW), respectively. Variability among the tested cultivars could serve as an important criterion for the selection of new high-performing cultivars for a given growing region

Uticaj agril termozaštitne tkanine na proizvodnu vrednost i kvalitet ploda sorte jagode 'Clery'

The influence of agril foil utilization on the parameters of production value (flowering and ripening time, yield and physical fruit traits) and fruit quality attributes (chemical properties, total antioxidant capacity and sensorial traits) of strawberry cultivar 'Clery' were studied. Investigations were carried out during 2009. on the private strawberry field located in Grocka. Strawberry plants covered with agril foil weighing 19 g/m2 at the beginning of March 2009. with goal to stimulate their intensive growth and to provide frost protection during the flowering season. Earlier flowering and ripening time were registered in cv 'Clery' grown under agril foil (03.04. and 01.05., respectively), but also mentioned phenological phases lasted longer. A positive influence of agril foil was observed in number of fruits per plant (40,4), however better results regarding yields and physical fruit properties were obtained without foil applying. In this case, higher yield obtained per plant (1.029,9 g) can be explained by larger fruits registered on the plants without agril foil (29,8 g). The soluble solids content ranged from 7,5% (control) to 8,10 % (with agril foil). The same trend can be observed with total phenolic content achieving higher value in the fruit of cv 'Clery' grown under agril foil (2,25 mg GA/g FW). Consequently, the highest total antioxidant capacity, which is of importance not only for maintaining the nutritional value and sensorial fruit quality, but also because of considerable health benefits was also obtained in cv 'Clery' with agril foil utilization.U radu je ispitivan uticaj primene agril termozaštitne tkanine na parametre proizvodne vrednosti (fenologija cvetanja i zrenja, rodnost i fizičke osobine ploda) i kvaliteta ploda (hemijske osobine i antioksidativni kapacitet ploda) sorte jagode 'Clery'. Ispitivanja su izvedena 2009. godine, u privatnom zasadu jagode koji se nalazi u Grockoj. Agril termozaštitna tkanina težine 19 g/m2 postavljena je preko biljaka početkom marta 2009. godine sa ciljem ubrzavanja njihovog rasta i zaštite u fenofazi cvetanja tokom kritičnog perioda sa mogućim pojavljivanjem mraza. Raniji početak fenofaze cvetanja (03.04.) i zrenja (01.05.) registrovan je kod sorte 'Clery' pod agrilom, ali i duže trajanje pomenutih fenofaza. Pozitivan uticaj primene agril termozaštitne tkanine registrovan je i kod broja plodova po bokoru (40,4), međutim u pogledu visine prinosa i fizičkih osobina ploda bolji rezultati su ostvareni bez primene agrila. Zahvaljujući većoj masi ploda registrovanoj u kontrolnoj varijanti (29,8 g) ostvaren je i nešto veći prinos po bokoru (1.029,9 g) u poređenju sa prinosom dobijenim pod agrilom (960,1 g), ali značajnost razlika u dobijenim vrednostima nije ustanovljena. Sadržaj rastvorljivih suvih materija u plodu bio je 7,5% u kontroli i 8,1% u tretmanu sa agrilom. Nešto viši sadržaj ukupnih fenola takođe je registrovan u plodu sorte 'Clery' pod agrilom (2,25 mg GA/g sveže mase ploda), kao i viša vrednost antioksidativnog kapaciteta ploda (1,63 mg asc/g sveže mase ploda). Značaj antioksidativnog kapaciteta ploda se ogleda ne samo u očuvanju hranljive vrednosti i senzoričkog kvaliteta ploda, već i u zdravstvenoj korisnosti za ljudski organizam

Dehydration-related changes of peroxidase and polyphenol oxidase activity in fronds of the resurrection fern Asplenium ceterach L.

Asplenium ceterach belongs to a group of poikilohydric ferns and it can recover uninjured from an almost completely dehydrated state. In our study, short term dehydration (24h) at four different water potentials, resulted in moderate water loss (partial desiccation) in fern tissue. The main phenolic acids represented in A. ceterach were chlorogenic (CGA) and caffeic acid (CA) and their content decreased during the dehydration process. For the first time, peroxidase (POD) and polyphenol oxidase (PPO) isoforms were determined in the rustyback fern. The results exhibit the presence of numerous anionic POD isoforms, with pI ranging from 4.4 to 5.8, but none of the cationic isoforms was detected. Two PPO isoforms were identified, one anionic with pI 6.3 and one cationic with pI of about 9.0. Short-term dehydration brought about a remarkable increase in POD and PPO activity using CGA as a substrate. Changes in enzyme activity and content of substrates during dehydration may play an important role in the adaptation of the rustyback fern to water deficit, and increase the overall plant resistance to stress conditions.nul

Uticaj Prohexadione-Ca i zakidanja prvih serija mladih izdanaka na fiziološka svojstva lista i ploda sorte maline 'Willamette'

The research was designed to evaluate the effect of growth regulator Prohexadione-Ca (ProCa) and young canes removal on the changes of photosynthetic pigment content and modification activities of antioxidant enzyme defense system in leaves and fruits of raspberry cultivar 'Willamette' (Rubus idaeus L.). The experiment was performed in the period of 2011-2012. It consisted of five treatments: control - no treatment; 2ProCa - with 2 ProCa applications; Z - one removal of young canes; Z+2ProCa - young canes removal with 2 ProCa applications; 2Z - two removals of young canes. The first series of young canes were removed for the first time in mid-April and for the second time at the begining of May. In 2ProCa and Z+2ProCa treatments foliar application of ProCa was carried out twice during the period of April-May in interval of three weeks, i.e. when the primocane growth reached 30 cm in height. The following concentrations of ProCa: 125 ppm (first application) and 200 ppm (second application) were applied. Significantly higher mean values of chlorophyll b content were registered in the 2ProCa (42.84 μg·g-1 FW) and Z+2ProCa (46.12 μg·g-1 FW) treatment. The highest SOD and POD activities were found in leaves of new young canes which developed after the young canes removal was applied. Z+2ProCa treatment significantly increased CAT activity in raspberry leaves (63.51 U mg-1 prot.). Both of implemented measures, especially applied in combination, resulted in higher activity of CAT, POD and SOD enzymes in the fruits of the examined cultivar.U radu je proučavan uticaj retardanta rasta Prohexadione-Ca (ProCa) i pomotehničke mere zakidanja prvih serija mladih izdanaka na promene u sadržaju fotosintetskih pigmenata i modifikaciju aktivnosti enzima antioksidacionog zaštitnog sistema u listovima i plodovima sorte maline 'Willamette' (Rubus idaeus L.). Eksperiment izveden u periodu 2011-2012. godine obuhvatio je pet tretmana: kontrola - bez tretiranja; 2ProCa - sa dva tretiranja ProCa i bez zakidanja izdanaka; Z - sa jednim zakidanjem izdanaka i bez tretiranja ProCa; Z+2ProCa - sa jednim zakidanjem izdanaka i dva tretiranja ProCa; 2Z - sa dva zakidanja izdanaka i bez tretiranja ProCa. Prvo zakidanje mladih izdanaka je obavljeno sredinom aprila, a drugo krajem aprila u obe godine ispitivanja. U 2ProCa i Z+2ProCa tretmanu folijarna aplikacija sa ProCa vršena je dva puta u periodu april-maj u intervalu od tri nedelje srazmerno dinamici porasta novih izdanaka tj. u momentu kada oni dostignu visinu od 30 cm. Primenjene su sledeće koncentracije ProCa: 125 ppm (kod prvog tretiranja) i 200 ppm (kod drugog tretiranja). Statistički značajno veća prosečna vrednost sadržaja hlorofila b registrovana je u 2ProCa (42,84 μg·g-1 sveže mase lista) i Z+2ProCa (46,12 μg·g-1 sveže mase lista) tretmanima. Najveća aktivnost enzima superoksid dismutaze i peroksidaze registrovana je u listovima novih mladih izdanaka, koji su se razvili nakon primenjene mere zakidanja izdanaka. Z+2ProCa tretman je uticao na značajno povećanje aktivnosti katalaza u listovima maline (63,51 U mg-1 proteina). Obe navedene mere, a naročito primenjene u kombinaciji, uticale su na povećanje aktivnosti pomenutih enzima u plodu ispitivane sorte