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1.
Polymers (Basel) ; 16(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38732647

RESUMO

The degradation of the complex structure of lignocellulosic biomass is important for its further biorefinery to value-added bioproducts. The use of effective fungal species for the optimised degradation of biomass can promote the effectiveness of the biorefinery of such raw material. In this study, the optimisation of processing parameters (temperature, time, and s/w ratio) for cellulase activity and reducing sugar (RS) production through the hydrolysis of sugar beet pulp (SBP) by edible filamentous fungi of Aspergillus, Fusarium, Botrytis, Penicillium, Rhizopus, and Verticillium spp. was performed. The production of RS was analysed at various solid/water (s/w) ratios (1:10-1:20), different incubation temperatures (20-35 °C), and processing times (60-168 h). The Aspergillus niger CCF 3264 and Penicillium oxalicum CCF 3438 strains showed the most effective carboxymethyl cellulose (CMC) degrading activity and also sugar recovery (15.9-44.8%) from SBP biomass in the one-factor experiments. Mathematical data evaluation indicated that the highest RS concentration (39.15 g/100 g d.w.) and cellulolytic activity (6.67 U/g d.w.) could be achieved using A. niger CCF 3264 for the degradation of SBP at 26 °C temperature with 136 h of processing time and a 1:15 solid/water ratio. This study demonstrates the potential of fungal degradation to be used for SBP biorefining.

2.
Pathogens ; 13(2)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38392898

RESUMO

Fusarium species are common plant pathogens that cause serious crop losses worldwide. Fusarium spp. colonize not only the main host plants, crops, but also alternative hosts. The effectiveness of fungicide use in disease management ranges from very successful to possibly promoting the growth of the pathogen. Triazole fungicides are widely used to control these pathogens due to their broad-spectrum activity and systemic nature. This paper reviews the sensitivity of 40 Fusarium strains isolated from weeds, non-gramineous plants, and spring wheat to metconazole, prothioconazole, and tebuconazole. The effect of fungicides was determined by the percentage inhibition of F. graminearum, F. culmorum, F. sporotrichioides, and F. avenaceum fungal mycelial growth. The 50% effective concentration (EC50) values of all isolates on metconazole were lower than 2.9 mg L-1, prothioconazole EC50 ranged from 0.12 to 23.6 mg L-1, and tebuconazole ranged from 0.09 to 15.6 mg L-1. At 0.00025-0.025 mg L-1, the fungicides were ineffective, except for the growth of the F. avenaceum species. It was observed that isolates from weeds were more sensitive to low concentrations of fungicide than isolates from crop plants. In general, information is scarce regarding the comparison of fungicide resistance in Fusarium isolates from weed and crop plants, making this study an additional contribution to the existing knowledge base.

3.
Plants (Basel) ; 12(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765431

RESUMO

Products must be cleaned or otherwise treated to keep them clean when they are prepared for further production or when they are supplied fresh to the consumer. Cereals have significantly lower settling losses than succulent agricultural products, but the risks that can arise from their hydrothermal treatment before milling-where the cereals are moistened and left to rest for 14 h (temperature 30 °C)-are often underestimated. This operation creates a favourable environment for the development of micro-organisms, which, if not destroyed, can continue throughout the processing stages and be passed on to the consumer. This study investigated the qualitative characteristics of winter wheat hydrothermally treated with ozonated water at a concentration of 1.51 ± 0.1 mg L-1, such as the amount of mould in the grains and flour, as well as the grain protein, moisture, gluten, sedimentation, starch and weight per hectolitre. For the assessment of these parameters, the account was taken of the State standard, which provides the grain class and the type of grain. The reduction in mould fungi after the treatment of the winter wheat grain with ozonated water ranged between 440 and 950 CFU g-1. The results of the microbiological analysis showed that the ozone treatment improved the mycological safety of the flour samples made from the grain from an average of 390 ± 110 CFU g-1 to 29 ± 12 CFU g-1. On the other hand, the treatment of kernels with ozonated water did not significantly affect the basic composition of the winter wheat grains.

4.
Antioxidants (Basel) ; 12(5)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37237864

RESUMO

Hemp inflorescences are a source of vital compounds, including phytocannabinoids and other biologically active compounds. Various methods are adapted for the extraction of these vital compounds such as the use of different organic solvents. This study aimed to assess the comparative extraction potential of three different solvents: deionized water, 70% methanol (MeOH), and 2% Triton X-100, for phytochemicals in hemp inflorescences. Spectrophotometric techniques were applied to investigate the total amount of polyphenolic compounds (TPC), total flavonoids contents (TF), phenolic acids (TPA), and radical scavenging activity (RSA) in hemp extracts obtained using different polarity solvents. Gas chromatography-mass spectrometry was used for cannabinoids and organic acids quantitative analysis. In the results, MeOH showed a better affinity for the recovery of TFC, TPA, and RSA in comparison to Triton X-100 and water. However, Triton X-100 performed better for TPC with 4-folds and 33% turnover compared to water and MeOH, respectively. Six cannabinoids (CBDVA, CBL, CBD, CBC, CBN, and CBG) were identified in hemp inflorescence extracts. The maximum determined concentration was as follows: CBD > CBC > CBG > CBDVA > CBL > CBN. Overall, fourteen organic acids were identified. Hemp inflorescence extracts obtained using 2% Triton X-100 showed an effect on all tested strains of microorganisms. Methanolic and aqueous extracts had antimicrobial activity against seven tested strains. On the other hand, the inhibition zones were wider for methanolic extracts compared to aqueous ones. Hemp aqua extract with antimicrobial activity might be used in various markets where toxic solvents are unwanted.

5.
Plants (Basel) ; 12(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36987023

RESUMO

Glyphosate is one of the most widely used herbicides, but is still in the spotlight due to its controversial impact on the environment and human health. The main purpose of this study was to explore the effects of different glyphosate usages on harvested grain/seed contamination. Two field experiments of different glyphosate usage were carried out in Central Lithuania during 2015-2021. The first experiment was a pre-harvest application, with two timings, the first according to the label (14-10 days), and the other applied 4-2 days before harvest (off-label), performed in winter wheat and spring barley in 2015 and 2016. The second experiment consisted of glyphosate applications at label rate (1.44 kg ha-1) and double dose rate (2.88 kg ha-1) at two application timings (pre-emergence of crop and at pre-harvest), conducted in spring wheat and spring oilseed rape in 2019-2021. The results suggest that pre-emergence application at both dose rates did not affect the harvested spring wheat grain or spring oilseed rape seeds-no residues were found. The use of glyphosate at pre-harvest, despite the dosage and application timing, led to glyphosate's, as well as its metabolite, aminomethosphonic acid's, occurrence in grain/seeds, but the amounts did not reach the maximum residue levels according to Regulation (EC) No. 293/2013. The grain storage test showed that glyphosate residues remain in grain/seeds at steady concentrations for longer than one year. A one year study of glyphosate distribution within main and secondary products showed that glyphosate residues were mainly concentrated in wheat bran and oilseed rape meal, while no residues found in cold-pressed oil and wheat white flour, when glyphosate used at pre-harvest at the label rate.

6.
Plants (Basel) ; 12(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36840316

RESUMO

The establishment of the harmful pathogen Fusarium graminearum in different agroecosystems may strongly depend on the ability of the soils to suppress its development and survival. This study aimed to evaluate the influence of different soil tillage systems (i.e., conventional tillage, reduced tillage and no-tillage) on soil fungistasis against F. graminearum. Soil samples were collected three times during the plant growing season in 2016 and 2017 from a long-term, 20-year soil tillage experiment. The F. graminearum in the soil samples was quantified by real-time qPCR. The soil fungistasis was evaluated by the reduction in the radial growth of F. graminearum in an in vitro assay. The antagonistic activity of the soil bacteria was tested using the dual culture method. The F. graminearum DNA contents in the soils were negatively correlated with soil fungistasis (r = -0.649 *). F. graminearum growth on the unfumigated soil was reduced by 70-87% compared to the chloroform fumigated soil. After the plant vegetation renewal, the soil fungistasis intensity was higher in the conventionally tilled fields than in the no-tillage. However, no significant differences were obtained among the tillage treatments at the mid-plant growth stage and after harvesting. 23 out of 104 bacteria isolated from the soil had a moderate effect, and only 1 had a strong inhibitory effect on the growth of F. graminearum. This bacterium was assigned 100% similarity to the Bacillus amyloliquefaciens Hy7 strain (gene bank no: JN382250) according to the sequence of the 16S ribosome subunit coding gene. The results of our study suggest that the presence of F. graminearum in soil is suppressed by soil fungistasis; however, the role of tillage is influenced by other factors, such as soil biological activity, type and quantity of plant residues and environmental conditions.

7.
J Food Sci Technol ; 56(4): 2147-2157, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30996448

RESUMO

Vegetables are an important source of vitamins and minerals and are one of the most perishable products. Fresh vegetables need to be cleaned, sorted, washed and dried before entering distribution and trading systems. The quality of the product and the effect of the environment during preparation are very important. One method of stabilizing vegetable quality is the application of ozone, which is a strong disinfectant used to inactivate microorganisms. Ozone, when in contact with a product surface, does not leave any harmful by-products. This research aims to optimize carrot treatment with ozonated water and evaluate its effect and efficiency on the storage of products. A constant concentration of 1.53 ± 0.09 mg L-1 ozone in water was used, and processing times of 5, 10, 15 and 20 min were applied. The carrots' weight and changes to the mould population on the carrots' surface during storage were observed after treatment with ozonated water. A decrease in mycological contamination on washable vegetable surfaces occurred within the first 5 min, and longer processing times (more than 5 min) did not influence the efficacy of the treatment. Thus, using ozonated water at an ozone concentration of 1.53 ± 0.09 mg L-1 reduced the mould population by up to 99.99% and could also prolong carrot storage duration up to 1.7 times. Treatment of carrots with ozonated water had minimal impact on the carrots' weight.

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