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In this study, palynological characteristics of 23 specimens of Helichrysum Mill., representing 12 Iranian species were investigated. We evaluated pollen grains (25 per specimens) and tested them by 15 qualitative and quantitative characteristics using Scanning Electron Microscopy (SEM). Pollen grain descriptions of most species were presented for the first time in the world. The pollen grains were tricolporate, radially symmetrical and isopolar in all examined samples. They were small, and rarely medium in size. The polar outline view (amb) was the same among the species. The overall views of pollen grains were prolate-spheroidal, oblate-spheroidal, subprolate, prolate and spheroidal. However, the more abundant type was prolate-spheroidal. The exine sculpture was echinate, and tectum is perforate. The ANOVA test revealed a significant variation (P < 0.001) for all the quantitative characteristics. In PCA analysis, the colpus length, width, and length/width ratio traits, polar and equatorial axes length, were the most variable features and some species were characterised by these characters. Results indicated that a few qualitative characteristics such as polar outline view and exine sculpture lack taxonomic importance via their stability among species. Also, the palynological traits had enough potential to separate the taxonomic boundaries of H. rubicundum and H. globiferum, but approximately the species clustering pattern did not agree with Flora Iranica.
Forest regeneration is a natural process of forest resource reclamation through production of young ones (saplings and seedlings). Tree species show variable regeneration potential in different associations and response to natural and man-made factors. Banj oak (Quercus leucotrichophora A. Camus), one of the important forest forming tree species in western montane Himalaya, is facing regeneration failure in different locations. The present study attempted to assess the population structure and regeneration of Q. leucotrichophora and associated tree species in five different stands (sites) of a less explored region (Tehri Garhwal, Uttarakhand, Western Himalaya). To investigate the phytosociological attributes, ten sampling quadrats (400 m2) were laid in random sampling manner in each forest stand for surveying tree layer, 2 sub-quadrats (25 m2) for saplings, and 5 sub-quadrats (1 m2) for seedlings in each sampling quadrat. Among the studied forest stands, tree species richness ranged 8 to 11 (8.8±1.3), total stem density (ind/ha) 750 to 950 (846±85.6), and total basal area (m2/ha) 18.68 to 29.18 (24.1±3.9). Based on abundance data the banj oak showed ‘good’ regeneration statuses (density of seedling > saplings > adult trees) in all forests. The distribution of adult tree individuals into different size classes (DBH classes) also indicate ‘good’ regeneration pattern (higher density in lower size classes and gradual decrease in density towards higher classes or forming a reverse J-shaped pattern). However, majority of the banj oak associated species (e.g. Prunus cerasoides, Pyrus pashia, Rhododendron arboreum, etc.) represented ‘fair’ regeneration statuses (seedlings > or ≤ saplings ≤ adult trees). Overall, the results of this study shed light on the positive prospects for Q. leucotrichophora regeneration and the importance of sustainable coexistence between human communities and these vital forest ecosystems.
Abstract
The fungal genus Fusarium encompasses a diverse group of species responsible for synthesizing mycotoxins, particularly deoxynivalenol, fumonisin, and zearalenone and inducing Fusarium head blight in wheat. The research was undertaken over a period of two consecutive growing seasons (2020 and 2021) on the premises and facilities of the Hungarian University of Agriculture and Life Sciences (MATE). The objective of this study was to investigate the impact of growing season, nitrogen fertilization, and wheat variety on Fusarium infection as well as mycotoxin contamination in wheat kernel. Zearalenone was absent throughout the course of the two growing seasons, whereas deoxynivalenol was found solely in 2020. The findings demonstrate that nitrogen fertilization failed to exhibit a statistically significant impact on both Fusarium infection and mycotoxin production. The impact of wheat variety on Fusarium infection and deoxynivalenol was not found to be statistically significant. However, it exerted a significant effect on fumonisin production. The growing season exerted a statistically significant impact on the incidence of Fusarium infection and the ensuing contamination with mycotoxins, attributable to augmented precipitation levels in 2021 compared to 2020, specifically during the flowering period when the spike of wheat is highly susceptible to Fusarium infection.
Abstract
The acreage of English walnut (Juglans regia L.) is constantly expanding in Hungary, due to the favorable climatic conditions and economic importance. Last years, serious damage was reported from several orchards with high percentage of rotted, moldy kernels. The aim of this research was to identify the pathogens at different growth stages. Fungi were cultured from the spotty, shriveled and rotted kernels, and monosporic isolates were identified based on morphological characters and molecular markers (ITS region and tef1 locus sequences). Botryosphaeria dothidea and Diaporthe eres were identified in high proportion from symptomatic kernels. These species were also isolated from different parts of walnut trees in different seasons. D. eres was detected in a high proportion from asymptomatic buds in March, while the presence of both species was observed in symptomatic husks with Overnight Freezing-Incubation Technique (ONFIT) in June. Their optimal growth temperature defined to be between 20–25 °C, and the growth of D. eres isolates was completely inhibited at 35 °C.
Abstract
One of the major and yet unsolved threats for viticulture is the group of vascular fungal infections, the so-called grapevine trunk diseases. Besides their latent nature and the enormous number of associated pathogens, their control is also hampered by the lack of effective fungicides, directing growing attention toward the use of biocontrol agents. In the present study the isolation, identification, and characterization of a bacterial strain are presented, showing biocontrol potential against some main causal agents of grapevine trunk diseases. The strain was isolated from the wood of an asymptomatic grapevine and selected for the fungicidal activity against the pathogen Phaeomoniella chlamydospora. According to 16S rDNA, gyrA, and gyrB sequences, the isolate belongs to Bacillus velezensis species. Confrontation tests with the bacterium or with its fermentation broth further revealed growth inhibition and fungicide activity against Botryosphaeria dothidea, Eutypa lata and Diaporthe ampelina pathogens. Fractionation of the bacterial culture filtrate suggests that the antifungal agents secreted by the B. velezenzis isolate are mainly lipoproteins. Phytotoxicity tests were also carried out with the isolate, showing no harmful effects on grapevine foliar disks.
Abstract
Soluble dietary fibre (SDF) is well recognised for its remarkable effectiveness in promoting human health. This study utilised response surface methodology to evaluate the optimal conditions required to extract SDF (U-SDF) from Lentinula edodes via the ultrasonic-assisted hot-water method, and evaluated the hypolipidemic effects and anti-inflammatory effects of U-SDF. The optimal extraction conditions for U-SDF were ultrasonic power of 182 W, extraction time of 2 h, extraction temperature of 81 °C, and solid-liquid ratio of 1:24 (g mL−1). Under these conditions, the extraction rate of U-SDF reached 8.08%. U-SDF treatment significantly improved liver and kidney indices in diabetic mice, markedly reduced the levels of plasma triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and significantly increased the level of high-density lipoprotein-cholesterol (HDL-C) in a dose-dependent manner. U-SDF also improved adipose tissue injury in diabetic mice, significantly decreased the levels of cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α), and alleviated inflammation of the abdominal aorta. In conclusion, U-SDF from L. edodes is an excellent source of dietary fibres, which exhibit good hypolipidemic and anti-inflammatory activities, suggesting potential applications as a functional additive in diverse food products.
Abstract
Food industrial bacterial cells eliminate aflatoxin M1 (AFM1) at different ratios. The study aimed to investigate the effect of AFM1 on probiotic industrial bacteria (Lactococcus lactis ssp. lactis R703, Bifidobacterium animalis ssp. lactis BB12, and L. paracasei subsp. paracasei 431) and evaluating their AFM1 binding ability in naturally contaminated milk. The growth of the R703 strain was affected by AFM1 at 1.47 μg L−1 concentration. Peptidoglycan (PG) cell wall fractions of R703 and BB12 bound a significant amount of AFM1 from naturally contaminated milk under one-hour treatment, while L. paracasei 431 was not effective. PG was better absorbent for AFM1 than viable cells of BB12, while the difference was insignificant for the R703 strain. Increasing the time did not significantly change the mycotoxin binding of BB12, while for R703 PG the absorption seemed reversible. BB12 PG needs further analysis for biotechnological application in dairy products.
Abstract
The aim of this work was to microencapsulate propolis phenolic compounds using polycaprolactone as wall material by double emulsion solvent evaporation (w1/o/w2). Microencapsulation experiments were carried out by investigating the effect of sample/solvent ratio (10–100 mg mL−1), poly(ε-caprolactone) (PCL) concentrations (200–1,000 mg mL−1), poly(vinyl alcohol) (PVA) concentrations (0.5–2.5 g mL−1), and stirring speed (200–1,000 r.p.m.) on the microencapsulation efficiency of total phenolic content (TPC%) and antioxidant activity of propolis. The best microencapsulation conditions were selected according to the total phenolic amount and their antioxidant activity. Experimental results showed that all microencapsulation conditions had significant effects (P < 0.05) on total phenolic content and antioxidant activities. The best conditions were: 30 mg mL−1, 600 mg mL−1, 2 g mL−1, and 400 r.p.m. for sample/solvent ratio, PCL concentrations, PVA concentrations, and stirring speed, respectively, with values of 86.98 ± 0.03% for phenolic encapsulation efficiency, 53.81 ± 0.50% for free radical scavenging activity (DPPH), and 45,480 Trolox equivalent, mg TE/100 g dry weight for ferric reducing antioxidant power (FRAP). Under all encapsulation conditions, a significant positive correlation was observed between ferric reducing antioxidant power, free radical scavenging activity, and phenolic content.
Abstract
The effects of milk from different species (sheep/cow) and pH adjustment in the production of Requeijão cremoso, a kind of processed cheese, were investigated. The results showed that the sheep's Requeijão cremoso had higher pH (∼3%), lower yellowness index (∼11%), and lower brightness (∼12%) after 5 days of storage, and at least 40% lower hardness compared to the Requeijão made from cow milk. The pH adjustment did not change the visual appearance of the samples but affected their hardness in different ways, with an increase of up to 16% for the cheese from cow milk and a reduction of up to 39% for the cheese produced from sheep milk. The results suggested that the protein-protein interactions were favoured in the Requeijão cremoso from sheep milk, while a protein network with higher water holding capacity and increased hardness was observed for the samples from cow milk.
Abstract
This work used a carrageenan-based thrombosis model to determine the preventative effects of Lactobacillus plantarum YS1 (LPYS1) on thrombus. In thrombotic mice, LPYS1 improved the activated partial thromboplastin time (APTT), while decreasing the thrombin time (TT), prothrombin time (PT), and fibrinogen (FIB) content. In thrombotic mouse serum, LPYS1 decreased the levels of malondialdehyde (MDA), tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), nuclear factor kappa-B (NF-κB), and interleukin-1 beta (IL-1β), while also increasing the activities of superoxide dismutase (SOD) and catalase (CAT). Moreover, LPYS1 upregulated the mRNA expression levels of copper/zinc-SOD (Cu/Zn-SOD), manganese-SOD (Mn-SOD), and CAT in the colon tissues of thrombotic mice, while downregulating those of NF-κB p65, IL-6, TNF-α, and interferon-gamma (IFN-γ) mRNA. In tail vein vascular tissues, LPYS1 suppressed the mRNA expression levels of NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin. The abundances of both beneficial and pathogenic bacteria were altered by LPYS1. These findings show that LPYS1 has the capacity to protect mice from thrombosis, while also revealing some of the underlying mechanisms of this effect.
