Jarosław L. Przybył

Effect of Meadowsweet Flower Extract-Pullulan Coatings on Rhizopus Rot Development and Postharvest Quality of Cold-Stored Red Peppers

The study involved an examination of the antifungal activity on red peppers of pullulan coating (P) and pullulan coating containing either water-ethanol (P + eEMF) or ethanol extract of meadowsweet flowers (P + eEMF). Pullulan was obtained from a culture of Aureobasidium pullulans B-1 mutant. Both non-inoculated peppers and those artificially inoculated with Rhizopus arrhizus were coated and incubated at 24 °C for 5 days. The intensity of the decay caused by Rhizopus arrhizus in the peppers with P and P + eEMF coatings was nearly 3-fold lower, and in the case of P + weEMF 5-fold lower, than that observed in the control peppers. Additionally, the P + weEMF coating decreased, almost two-fold the severity of pepper decay compared to other samples. The influence of coating of pepper postharvest quality was examined after 30 days of storage at 6 °C and 70%–75% RH. All coatings formed a thin and well-attached additional layer of an intensified gloss. During storage, color, total soluble solid content and weight loss of coated peppers were subject to lower changes in comparison with uncoated ones. The results indicate the possibility of the application of pullulan coatings containing MFEs as an alternative to the chemical fungicides used to combat pepper postharvest diseases.

Influence of Storage Conditions on Flavonoids Content and Antioxidant Activity of Selected Shallot (Allium Cepa Var. Ascalonicum Backer) Hybrid Cultivars

Summary The aim of this study was to determine changes in the content of flavonoids in fleshy scales of shallot bulbs in relation to different compositions of atmosphere during storage. Also antioxidant activity of the bulbs was determined. Bulbs of shallot cvs. Bonilla F1, Conservor F1 and Matador F1 were stored in two storage seasons at the normal atmosphere (NA) and controlled atmosphere (CA) of the 4 compositions: 5% CO2 + 5% O2, 5% CO2 + 2% O2, 2% CO2 + 5% O2, 2% CO2 + 2% O2. The temperature of storage was 0-1°C and RH 65%. Before and after 7-month storage the bulbs were examined in respect of flavonoids content and antioxidant activity (AA). Flavonoids were identified in methanolic extracts with HPLC, AA was determined with FRAP and DPPH assays. Three flavonoid compounds were identified in the plants extracts. Quercetin 3,4’ di-O-glucoside and quercetin 4’-glucoside (spiraeoside) were present in the highest amounts. CA conditions influenced content of flavonoids in the bulbs. The highest content after storage was observed at gas composition of 5% CO2 + 5% O2. Two major flavonoid compounds, quercetin 3,4’-di-O-glucoside and quercetin 4’-O-glucoside (spiraeoside) showed the increasing tendency, however not all changes were significant. No significant differences were observed between cultivars, but ‘Bonilla’ F1 showed slightly higher flavonoids content than the other ones. Investigated cultivars did not differ in respect of AA, measured both with DPPH and FRAP assay. There was no significant influence of storage conditions on DPPH level, while FRAP level was influenced significantly. Bulbs from 5% CO2 + 2% O2 composition were characterized by the highest FRAP values and the bulbs stored at normal atmosphere - by the lowest. Streszczenie Celem pracy było zbadanie zmian w zawartości flawonoidów w łuskach mięsistych cebul szalotki w zależności od składu gazowego atmosfery podczas przechowywania. Badano również aktywność antyoksydacyjną cebul. Cebule szalotki odmian ‘Bonilla’ F1 ‘Conservor’ F1 i ‘Matador’ F1 przechowywano w dwóch sezonach przechowalniczych w atmosferze normalnej (NA) oraz kontrolowanej (CA) o czterech składach gazowych: 5% CO2 + 5% O2, 5% CO2 + 2% O2, 2% CO2 + 5% O2, 2% CO2 + 2% O2. Temperatura przechowywania była utrzymywana na poziomie 0-1°C, a wilgotność względna powietrza 65%. Przed przechowywaniem i po 7 miesiącach przechowywania oznaczano zawartość flawonoidów i aktywność antyoksydacyjną (AA). Flawonoidy identyfikowano w ekstraktach metanolowych przy pomocy HPLC. AA określano przy pomocy metod FRAP oraz DPPH. W ekstraktach zidentyfikowano cztery związki z grupy flawonoidów. W największych ilościach występowały 3,4’di-O-glucozyd kwercetyny oraz 4’glucozyd kwercetyny (spiraeozyd). Warunki CA wpłynęły na zawartość flawonoidów w cebulach. Największą zawartość stwierdzono po przechowaniu w atmosferze o składzie 5% CO2 + 5% O2. Dwa główne związki flawonoidowe, 3,4’di-Oglucozyd kwercetyny oraz 4’glucozyd kwercetyny, wykazywały tendencję wzrostową, jednak nie we wszystkich obiektach zmiany były istotne. Nie stwierdzono istotnych różnic między odmianami, jednak cebule odmiany Bonilla F1 wykazywały tendencję do wyższej zawartości flawonoidów niż cebule pozostałych odmian. Cebule badanych odmian nie różniły się istotnie pod względem AA mierzonej obu metodami. Nie stwierdzono wpływu składu atmosfery na AA mierzoną metodą DPPH, natomiast wpływ ten był istotny przy użyciu metody FRAP. Cebule przechowywane w atmosferze o składzie 5% CO2 + 2% O2 charakteryzowała wyższa AA mierzona metodą FRAP, natomiast przechowywane w NA - najniższa.

Phenolics in Primula veris L. and P. elatior (L.) Hill Raw Materials

Primula veris L. and Primula elatior (L.) Hill represent medicinal plants used for the production of herbal teas and preparations with antioxidant and expectorant activity. Flowers and roots of both species possess the same biological activity. In the presented study, raw materials of wild growing P. veris and P. elatior were compared in terms of the content and composition of phenolic compounds using a fast and simple HPLC-DAD method. The study showed that flowers of both species were rich in flavonoids. However, P. veris flowers were characterized with a distinctly higher content of isorhamnetin-3-O-glucoside, astragalin, and (+)-catechin, whereas P. elatior occurred to be a richer source of rutoside and isorhamnetin-3-O-rutinoside. Hyperoside was found exclusively in P. elatior flowers. Phenolic glycosides (primverin and primulaverin) were identified only in the roots. Their content was about ten times higher in P. veris in comparison with P. elatior underground organs. The obtained results clearly show that both Primula species differ distinctly in terms of the content and composition of phenolic compounds. The compounds differentiating both species to the highest degree (hyperoside, in flowers, as well as primverin and primulaverin, in the roots) may be useful chemical markers in the identification and evaluation of both species.

Accumulation of phenolic compounds in the purple betony herb (Stachys officinalis L.) originated from cultivation

Summary Introduction: Purple betony (Stachys officinalis L., Lamiaceae) is a perennial of versatile medicinal usage. Nowadays, in Poland betony herb is collected exclusively from wild growing plants. Decreasing number of its natural sites results in lack of the herb supply and thus, in its limited usage. Objective: The aim of the study was to determine the effects of the age of plant and term of raw material harvest on its yield and quality in cultivation conditions. Methods: The observations were carried out on 2- and 3-year-old plants. During vegetation the herb was collected for four times. The raw material was subjected to chemical analysis. Tannins (as pyrogallol equivalent) were determined according to Polish Pharmacopoeia, phenolic acids and flavonoids – by HPLC. Results: The mass of herb, both in the second and third year, had increased from the beginning of vegetation up to seed setting. The highest content of tannins was found in the herb collected at the vegetative stage of plant development (2.05% in the second and 2.91% in the third year). Four phenolic acids (chlorogenic, ferulic, caffeic and rosmarinic acids) and five flavonoid compounds (orientin, luteolin-7-glucoside, apigenin-7-glucoside, apigenin-3-glucoside, apigenin) were identified in the obtained raw materials. In these groups, the dominant compounds were caffeic acid and apigenin. The highest content of caffeic acid was found at the beginning of plant vegetation, whereas apigenin – at the stage of full blooming and seed setting. Conclusion: In cultivation conditions, purple betony produces high mass of herb which may be used as a valuable raw material in herbal industry.

Variability of southern sweet-grass (Hierochloë australis /Schrad./ Roem. & Schult.) wild growing populations occurring in eastern Poland

Summary Southern sweet-grass is a perennial grass distributed through north-eastern Europe. In Poland, this rare, partially protected plant grows wild in well-lit coniferous or mixed forests. Its leaves, rich in coumarin compounds, are used for aromatization of alcohols. Taking into account high demand on this raw material and decrease in the number of southern sweet-grass populations it is recommended to introduce the plant into cultivation systems. In this study 12 populations of southern sweet-grass were selected and assessed in terms of their cultivation usefulness. The presence of associated plant species growing on its natural sites was investigated as well as light irradiance on those stands. The species was found in 3 types of forest communities. Air dry mass of leaves per plant varied in analyzed populations from 1.73 to 11.07 g. They were significantly diversified in the total content of coumarins (0.36–0.96%), flavonoids (0.09–0.26%) and polyphenolic acids (0.13–0.29%). The diversity concerning the content of coumarin, a quality indicator of leaves, was even higher. The content of this compound varied from 52.03 to 275.74 mg/100 g d. m. Among the analyzed populations, the most interesting seem to be population No. 12 (Jedwabno) and population No. 10 (Ruciane) characterized with relatively high mass of leaves and the highest content of the identified active compounds, including coumarin.

Functional traits of selected clones of southern sweet-grass (Hierochloë australis /Schrad./ Roem. & Schult.)

Summary Southern sweet-grass (Hierochloë australis /Schrad./ Roem. & Schult., Poaceae), commonly known as a bison grass, is a perennial tuft grass rarely occurring in mixed forests in Eastern and Northern Europe. The raw material collected from this plant are leaves rich in coumarin compounds (especially coumarin) responsible for sweet, specific aroma of these organs. In Poland, southern sweet-grass leaves are used mainly for alcohol products aromatisation. Growing demand for the raw material results in uncontrolled and excessive collecting of this plant. The best way to solve this problem is to introduce this plant into cultivation. Since southern sweet-grass is allogamous and heterozigotic, strong intraspecific variability of the species is observed. Fourteen clones of selected individuals from one population of southern sweet-grass naturally occurring in East Poland were compared in respect of morphological traits as well as accumulation of biologically active compounds. The clones differed significantly in the weight of leaves (3.76-22.59 g of air-dry weight per plant). The total coumarin content (determined by a spectrophotometric method) in this raw material for investigated clones ranged from 1.49 to 1.94%, flavonoids - from 0.25 to 0.55%, and phenolic acids - from 0.20 to 0.42%. Three coumarin compounds were identified by HPLC, namely coumarin, 3,4-dihydrocoumarin, and o-coumaric acid. The content of coumarin ranged from 84.00 to 310.85, 3,4-dihydrocoumarin: from 17.80 to 168.45, and o-coumaric acid: from 37.50 to 70.00 mg · 100 g-1 dry matter. Streszczenie Turówka leśna (Hierochloë australis /Schrad./ Roem. & Schult., Poaceae), potocznie nazywana żubrówką, jest wieloletnią trawą kępkową występującą rzadko na stanowiskach naturalnych w Europie Północnej i Wschodniej. Rośnie ona na brzegach lasów liściastych i mieszanych. Surowcem pozyskiwanym z tej rośliny (wyłącznie ze stanowisk naturalnych) są liście bogate w związki kumarynowe, a w szczególności w kumarynę, odpowiedzialną za specyficzny słodkawy aromat liści. W Polsce surowiec ten wykorzystywany jest głównie do aromatyzowania napoi alkoholowych. W ostatnich latach obserwuje się rosnący popyt na ten surowiec, co skutkuje niekontrolowanym i nadmiernym jego pozyskiwaniem. Jednym z najbardziej skutecznych sposobów zapobieżenia temu zagrożeniu wydaje się być wprowadzenie turówki leśnej do uprawy. Jest to roślina obcopylna i heterozygotyczna, u której obserwuje się wyraźne zróżnicowanie wewnątrzgatunkowe. W niniejszej pracy przeprowadzono charakterystykę morfologiczną i chemiczną czternastu klonów tej rośliny uzyskanych z wybranych pojedynków z populacji turówki leśnej rosnącej we Wschodniej Polsce. Badane klony różniły się istotnie masą liści (od 3,76 to 22,59 g suchej masy na roślinę). Ogólna zawartość kumaryn w tym surowcu wahała się od 1,49 do 1,94%, flawonidów - od 0,25 do 0,55% i kwasów fenolowych - od 0,20 do 0,42%. Trzy związki kumarynowe zostały zidentyfikowane w liściach badanych klonów przy użyciu HPLC, tj. kumaryna, 3,4-dihydrokumaryna i kwas o-kumarowy. Zawartość kumaryny wahała się od 84,00 do 310,85, 3,4-dihydrokumaryny: od 17,80 do 168,45, a kwasu o-kumarowego: od 37,50 do 70,00 mg · 100 g-1 suchej masy.

Antioxidant and Antibacterial Activity of Roseroot (Rhodiola rosea L.) Dry Extracts

Roseroot (Rhodiola rosea L.) belongs to plants revealing adaptogenic properties, which are attributed to the presence of specific phenolic compounds and are reflected mainly as antioxidant activity. The aim of the present study was to determine the antioxidant and antibacterial activity of various products obtained from R. rosea (underground organs as well as their aqueous and ethanolic dry extracts) in relation to the chemical profiles of phenolic and essential oil compounds. The chemical profiles were determined by High-performance Liquid Chromatography with a diode-array detector (HPLC-DAD) and Gas chromatography-mass spectrometry (GC-MS), antioxidant activity by (1,1-Diphenyl-2-picrylhydrazyl) Scavenging Capacity Assay (DPPH), (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) Scavenging Capacity Assay (ABTS) and Ferric Reducing Antioxidant Power Assay (FRAP) and antimicrobial properties were expressed as minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) values following the broth microdilutions method. The results show that the investigated samples differed in terms of their chemical compositions and biological activities. The extracts were more abundant in phenolic compounds (salidroside, tyrosol, and rosavin derivatives) in comparison to dried underground organs. The content of the determined phenolics in the analyzed extracts was affected by the solvent used for extraction. The ethanolic extract was characterized by the highest content of these substances in comparison to the aqueous one and the dried raw material, especially with regard to rosavin (969.71 mg/100 g). In parallel, this extract showed the strongest antioxidant and antibacterial activity. However, dried R. rosea underground organs also revealed strong antibacterial effects against, for example, Staphylococcus strains.

Chemical variability of common skullcap (Scutellaria galericulata L.) wild growing in the area of eastern Poland

Summary Introduction. In the group of plants revealing adaptogenic activity, species belonging to Scutellaria genus are considered to be the most important ones. Common skullcap (Scutellaria galericulata L.) is less known species from this genus, growing wild in Poland in wet habitats. Its herb has been used in the past as a sedative and diuretic agent. Objective. The aim of the study was to determine the variability of common skullcap in terms of the accumulation of flavonoids in the herb. Methods. The objects of the study were 17 common skullcap populations growing wild in eastern Poland. At each natural site, the list of main flowering plant species was carried out, according to Braun-Blanquet scale of plant abundance. The total content of flavonoids was determined according to EP 8th. The analysis of flavonoids was carried out using HPLC, Shimadzu chromatograph. Results. The total content of flavonoids ranged from 0.21 to 0.50% dry matter (DM). Using HPLC, eight compounds were identified within the group, with chrysin-7-O-glucuronide (30.91–589.27 mg × 100 g−1 DM), baicalin (61.90–482.93 mg × 100 g−1 DM) and scutellarin (43.77–213.54 mg × 100 g−1 DM) as dominants. Chrysin was the compound which in the highest degree differentiated investigated populations (CV=0.77). Conclusion. Obtained results indicate that investigated common skullcap populations differed in terms of the total content of flavonoids as well as the content of indentified flavonoids in the herb. However, there was no clear relationship between geographical localization of populations and the content of identified flavonoids in raw material.

Antimicrobial effect of an aqueous extract of Potentilla erecta rhizome

Abstract Potentilla erecta is a therapeutic plant used in folk medicine to treat inflammatory states, wounds and diseases of the alimentary tract. The results of the study reveal the effects of an aqueous extract of P. erecta rhizome on certain microorganisms occurring in food. The main components of the extract were catechins. The extract was shown to display an inhibiting effect against Gram-positive bacteria such as Staphylococcus aureus ATCC 25923 and Bacillus subtilis ATCC 6633, as well as against yeast such as Candida lipolitica KKP 322 and Hansenula anomala R 26. The extract did inhibit the growth of Gram-negative bacteria, however, no inhibiting effects were observed on moulds in the studied range of concentrations, i.e. 0.13 to 64 mg dry matter/ml.