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Celem badań było porównanie potencjału antyoksydacyjnego ekstraktów wodnych z liści żółtych i zielonych miłorzębu dwuklapowego oraz zielonych morwy białej. W pracy oznaczono zdolność zmiatania wolnych rodników DPPH a także oznaczono zawartość związków fenolowych w otrzymanych ekstraktach. Najlepszymi właściwościami przeciwutleniającymi charakteryzował się ekstrakt sporządzony z żółtych liści miłorzębu dwuklapowego. Posiadał on też najwięcej związków fenolowych w swoim składzie. Mniejszy potencjał antyoksydacyjny miał ekstrakt z morwy białej podobnie posiadał mniej związków fenolowych. Jednak najmniej związków aktywnych oraz najniższym potencjałem antyoksydacyjnym charakteryzował się ekstrakt sporządzony z zielonych liści miłorzębu dwuklapowego.
The article presents results of research on the micromorphology and anatomy of leaves of Morus alba cultivars. Mature leaves from generative shoots were collected in the Cytadela Park in Poznań and from trees planted along streets in different towns in the Wielkopolska region. A light microscope and a scanning electron microscope were used for observations. There were significant differences between the adaxial and abaxial epidermis. The idioblasts are found on the adaxial surface and stomata on the abaxial surface. Stomata can be classified into two types small and large. Several types of trichomes were recognized on the leaves: straight or hooked, unicellular, glandular capitate, spherical to elliptic stalked. Anatomical investigations revealed that leaves of M. alba cultivars were bifacial and the multi-layered mesophyll was diversified into palisade parenchyma and spongy palisade-like parenchyma. The research findings may be used for the identification of M. alba cultivars, while the epicuticular traits may be useful for the identification and classification of fragments of fossil leaves. The article includes descriptions and illustrations of several new quantitative and qualitative characters of the petiole and lamina, which have not been published previously and are described for the first time from Poland.
A three-step procedure was adopted for the induction of gynogenesis in two cultivars of mulberry (Morus alba L.). This includes in vitro flowering, inflorescence segment culture and isolated ovary culture. In the third step, that is, isolated ovary culture, the cultured ovaries burst and an embryo emerged from the ovary. The present paper investigates the ontogeny of the developing gynogenic embryo. The study confirmed that the gynogenic embryo emerged from the egg cell. Before the onset of division of the egg, all other cells of the embryo sac degenerated in the majority of ovules, but in exceptional cases the polar nuclei will be retained along with the dividing egg cell. The presence of the gynogenic embryo along with free-nuclear autonomous endosperm is the most important feature of the present investigation. Autonomous endosperm is formed from either the polar nuclei or secondary nucleus. In both cultivars used for the experiment, the percentage of ovaries showing proembryo induction during inflorescence segment culture is much higher than that of ovaries producing gynogenic plants during isolated ovary culture. This suggests the degeneration of some gynogenic embryos during the initial stages of induction.
W pracy oceniano możliwość przechowywania pąków wierzchołkowych i bocznych morwy w warunkach spowalniających procesy wzrostu i rozwoju. Hodowlę in vitro prowadzono w fitotronie w temperaturze 4°C, w warunkach ograniczonego oświetlenia. Zastosowano pożywkę charakteryzująca się obniżoną zawartością makro- i mikroelementów oraz witamin, dużym stężeniem węglowodanów, a także obecnością retardantów. W czasie przechowywania obserwowano żywotność eksplantatów. Po upływie 6 miesięcy zaobserwowano żywotność 90% eksplantatów wierzchołkowych i 76% eksplantatów bocznych. Współczynnik namnażania eksplantatów po przeniesieniu na pożywkę namnożeniową kształtował się od 6,2 dla eksplantatów bocznych do 7,5 dla eksplantatów wierzchołkowych. Zastosowanie mniejszej objętości pożywki miało negatywny wpływ na kondycję eksplantatów podczas przechowywania, jednak ekspalntaty charakteryzowały się wyższym współczynnikiem namnażania niż eksplantaty przechowywane w większej objętości pożywki.
The paper presents the results of a biometrical study on the leaves of vegetative and generative shoots of Morus alba. Mature leaves were collected from the green areas of Poznań (Poland) city. Leaves from vegetative shoots were collected from 34 sites. Leaves from generative shoots were collected from specimens with blackish purple or purple fruit (13 trees) and with pale yellow to creamy fruit (21 trees). Eleven morphological traits were analysed in the leaves from vegetative and generative shoots, including the petiole and blade. The seven examined features were characterised by low or moderate variability and four features were characterised by high or very high variability. The research revealed slight differences between trees with blackish purple or pale yellow fruit and significant morphological differences between the leaves of vegetative and generative shoots. The article includes descriptions of quantitative features have not been published in Poland. White mulberry leaves (Morus alba) with white and dark fruit did not make clearly separated groups. Therefore, they should be treated as morphotype of cultivars rather than a distinct taxonomic rank.
ntroduction: Powder extracts from white mulberry leaves (Morus alba L.) are desirable due to their simplicity of use. Powders intended for use in food and dietary supplements can be obtained by various methods, including water extraction and spray drying. Objective: The aim of the work was to optimize the aqueous process of extraction of white mulberry leaves and characterization of bioactive properties of the obtained extract powder. Methods: The DNJ and flavonoids (quercetin, kaempferol) contents and were analysed by high performance liquid chromatography (HPLC). Total phenolic contents were determined using the Folin-Ciocalteu phenol reagent and antioxidant activity by ABTS and DPPH assays. Results: The mulberry leaf extraction process has been optimized. The obtained powdered mulberry leaf extract proved to be a good source of bioactive compounds. Characteristic phenolic compounds detected in mulberry leaves and their powder extract were quercetin and kaempferol. The sum of polyphenols was 10.9 mg GAE/g dry matter in the raw material, whereas in the powder extract 42.6 mg GAE/g dry matter. In addition, it was found that the obtained powdered extract is characterized by a five-fold higher, in comparison to the raw material, the content of antioxidant activity measured by ABTS and DPPH tests. The content of 1-deoxynojirimycin (DNJ) in the powder extract was nearly four times higher than in dry mulberry leaves. Conclusion: The optimized process of water extraction of white mulberry leaves allows to keep valuable bioactive components and to obtain their high concentration.
Morus genus includes more than 20 species, some of which are commercially important mulberries with different fruit color and shape. Even though the trees of those species are propagated by rooting of cuttings in practice, mulberry seeds are of importance for breeding studies and rootstock seedling propagation. For that reason, this study was conducted to improve the seed performance of four mulberry species by different pre-sowing treatments including; 3% KNO3, GA3 at 500 ppm, organic priming with herbal tea brewed from marigold flowers petals and hydro priming. Results of the parameters of emergence characteristics and seedling vigor were evaluated. According to the results that varied between different species and pre-treatments, since emergence percentage and time, and seedling vigor were improved by the treatments, it was concluded that pre-sowing applications, especially GA3 and hydro priming, were beneficial in improving the seed performance of mulberry species included in the study.
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