In a laboratory experiment, we studied the insecticidal effects of invasive alien plants on the rice weevil. The research was carried out in two parts. In the first part, we studied the insecticidal ...properties of seven different plant species, namely, Bohemian knotweed (Fallopia × bohemica), Japanese knotweed (Fallopia japonica), false indigo-bush (Amorpha fruticosa), tree of heaven (Ailanthus altissima), staghorn sumac (Rhus typhina), Canada goldenrod (Solidago canadensis), and giant goldenrod (Solidago gigantea). Mixtures of powders and wheat were prepared in two different concentrations, namely, 2.5 w% and 1.25 w%. The experiment was performed at temperatures 20 °C and 25 °C and at two humidity levels, 55% R.h. and 75% R.h. Very low mortality (below 8%) was found when using combinations with the higher relative humidity. No significant differences were observed between the effects of these concentrations. In the second part of the experiment, Norway spruce wood ash and diatomaceous earth (product SilicoSec®) were added to the powder obtained by milling leaves of four different invasive plant species (Canada goldenrod, staghorn sumac, tree of heaven, false indigo). In the independent application, wheat was added to the powder at a concentration 2.5 w%. In the treatments that involved mixtures of powder and wood ash/diatomaceous earth, we applied 1.25 w% plant powder and 1.25 w% wood ash or 1.25 w% plant powder and 450 ppm of a SilicoSec® preparation. The positive control was carried out as two separate treatments with 2.5 w% wood ash of Norway spruce and 900 ppm of the SilicoSec® product, while untreated wheat represented the negative control. The experiment was performed at two temperatures (20 °C and 25 °C) and two R.h. values (55 and 75% R.h.). The mortality of beetles was recorded on the 7th, 14th, and 21st day after the start of the experiment. Higher mortality rates of rice weevil adults were found at the higher relative humidity, and an important factor of mortality was also the day of exposure, as a higher mortality was found when the exposure of individuals to the tested substances was for a longer time period. After 21 days at 25 °C and 55% R.h., the combinations in which the lower concentration of Norway spruce wood ash was added to the powder of invasive alien plants achieved more than 90% mortality of beetles. By adding the plant powder of invasive alien plants to wood ash, we achieved a greater insecticidal efficacy of invasive plants and lower concentrations of wood ash. Nevertheless, the results of our research do not indicate any great usefulness of the plant powder of invasive plants in suppressing the rice weevil. Additional studies should primarily focus on the insecticidal efficacy of powder from the genus Solidago, which in our study, displayed the greatest insecticidal potential among the tested invasive plants.
The importance of authenticity characterization is an increasing and pressing requirement for all foods. Vegetable oil is one of the most studied foods because of its nutritional and medicinal ...properties in a correct diet. In this study, a total of 53 Camelina sativa samples, from all known growing areas, were chemically and isotopically characterized. The fatty acid content of camelina oil was determined by gas chromatography (GC), and the ratios of stable carbon isotopes (13C/12C) of individual fatty acids and seed/bulk oil were determined by gas chromatography−combustion-stable isotope ratio mass spectrometry (GC/C/IRMS) and elemental analysis−stable isotope ratio mass spectrometry (IRMS). A total of 17 different fatty acids were detected by GC, with ω3 α-linolenic acid (C18:3n3) being the most abundant (29.7−40.0 wt %). Oleic acid (C18:1n9), linoleic acid (C18:2n6) and eicosenoic acid (C20:1n9) all belong to the second group of major fatty acids. The stable carbon isotopic values (δ13C) fell into a range typical for C3 plants. The use of δ13C18:2n6 vs δ13C18:3n3 correlation could show cases where impurity or adulteration is suspected, whereas principal component analysis clearly separates oil samples from different continents. Preliminary results on the camelina oil authentication procedure provide a basis for the investigation of geographical origin and the further distinction between camelina and camelina refined or other, less expensive oils.
Four types of nozzles were tested on large-scale trials with a 40 m2 plot unit size. The Avi Twin 110-01 (80 L ha−1), 110-02 (160 L ha−1), 110-03 (240 L ha−1), and 110-04 (320 L ha−1) symmetric ...double fan injector nozzles were tested during the 2020/2021 and 2021/2022 growing seasons. This study aimed to evaluate the performance of spray nozzles with regard to deoxynivalenol (DON) accumulation in durum wheat grains. Artificial inoculation with Fusarium spp. was performed after durum heads were protected with fungicide. The percentage of heads covered with fungicide droplets, grain yield, yield-related traits, technological quality parameters, and concentrations of DON were determined. Compared to the control (without fungicide treatment), the Avi Twin 04 nozzle caused a reduction of 45.0% in the DON concentration on average across both growing seasons. This positively corresponded to the percentage of heads covered with fungicide droplets, which was highest when this nozzle was utilized. In both trial years, the DON reduction caused by the 110-04 twin nozzle was higher than that caused by the 110-01 nozzle. Treatment with the 110-04 nozzle more effectively improved the grain yield, 1000-kernel weight, and test weight compared to treatment with the 110-01 nozzle and the untreated control. The differences in technological quality were less pronounced when different spray nozzles were used.
Polyphenols from Slovenian hops (Humulus lupulus L.) of the Aurora variety were extracted by different methods and using classical solvents and several deep eutectic solvents (DES) based on choline ...chloride as the hydrogen bond acceptor component. The obtained extract solutions were analyzed by HPLC for the content of extracted α- and β-acids and extracted xanthohumol. It was found that choline chloride:phenol DES concentrated aqueous solution had an extraction efficiency close to that of diethyl ether, which is considered one of the best classical extraction solvents for polyphenols from hops. The comparison of the extraction efficiency with other choline chloride-based DESs showed that the chemical similarity of the phenol ring in the solvent DES with the polyphenols in hops may be crucial for a highly efficient extraction with choline chloride:phenol DES. On the other hand, the choice of extraction method and the viscosity of the solvents tested seem to play only a minor role in this respect. As far as we know, this is the first study to attempt to relate extraction efficiency in the extraction of hydrophobic solutes to the compressibility of the DES extractants, the latter of which may be correlated with the extent of hydrophobic hydration around the DES components. In addition, using the heating and stirring method for the preparation of choline chloride-based DES concentrated aqueous solutions we found no support for the occurrence of water in two different roles (in the structural and in the dilution role) in these solvents.
The influence of deodorization parameters (temperature (T), steam flow (S), time (t)) on the phenolic content and radical scavenging effectiveness (RSE) of methanolic extracts of camelina oil was ...investigated and analyzed by response-surface methodology (RSM). The phenolic content can be considered to be a linear function of all three parameters. A positive linear relationship between the content of phenolic compounds in deodorized oils and RSE was observed. Deodorization at 210 °C with a steam flow of 3 mL/h for 90 min resulted in the best preservation of phenolics, amounting to 29.9 mg/kg. The lowest reduction from RSE of 12.4 μM Trolox equivalents (TE)/g oil for the crude oil was observed for oil treated at 195 °C and 18 mL/h for 60 min with RSE of 10.1 μM TE/g oil. The lack of correlation between RSE or total phenolic content and oxidative stability (OS) of the deodorized oils suggests that antioxidants in scavenging radicals react by different mechanisms, depending on radical type and reaction medium.
Satureja montanaL. and S. subspicata Vis. (Lamiaceae) are used for centuries in traditional medicine of Balcanic people in the healing of the lymphatic nodule and respiratory system inflammation. In ...this paper the amount of total phenols and flavonoids (analyzed by UV/Vis spectrophotometry), phenolic compounds profile (analyzed by HPLC), antimicrobial and antioxidant activities were studied in samples collected in seven per species populations of S. montanaand S. subspicatain Croatia. Eight phenolic compounds (rutin, quercetin, caffeic, p-coumaric, ellagic, protocatehuic, rosmarinic, and syringic acid) were identified and quantified using HPLC in methanolic and ethanolic extracts. Results showed that both species contained polyphenolics and other antioxidant compounds with chelating and radical-scavenging properties. The extracts prepared from both species showed broad spectrum of antimicrobial activity on in vitrotested microbial species (Staphylococcus aureus, Escherichia coli, Candida albicans, C. dubliniensis, C. krusei, C. glabrata, C. parapsilosis, and Microsporum gypseum).
We tested the insecticidal efficacy of different powders as surface treatment against the rice weevil (Sitophilus oryzae) adults. We have applied dusts from five invasive alien plant species ...(Solidago canadensis, Solidago gigantea, Amorpha fruticosa, Rhus typhina, Ailanthus altissima) and two inert dusts, i.e. wood ash from Norway Spruce (Picea abies) and commercial product SilicoSec® (as diatomaceous earth). Mortality was evaluated from 1st till 7th day after exposure, at 20 and 25 °C, two values of relative humidity and two doses (20 and 40 g/m2). After Day 7, alive beetles were placed into clean Petri dishes, and mortality counts were measured from 8th till 14th day. In general, we have detected poor efficacy of plant powders against S. oryzae. SilicoSec® at 20 g/m2 caused 100 % mortality at 25 °C and 55% RH, after seven days. Wood ash (13.46% SiO2) was less effective in comparison to SilicoSec® (79.48% SiO2), as approx. 60% mortality was recorded at the same conditions. We have detected that leaves of A. altissima and flowers od S. gigantea are rich with polyphenols (like catechin hydrate), on average almost 17 mg/g in S. gigantea flowers. Flowers and leaves of Solidago species are also rich with essential oil, like beta-copaene. The results of our research indicate that the powders of invasive plants are closer to fragrant roses in controlling S. oryzae adults, while the gun for this pest is only diatomaceous earth. To improve the effectiveness of invasive plant products, we suggest testing their independent effectiveness in liquid form as well as combinations of their essential oils with inert dusts.
•Insecticidal efficacy of powders of tested invasive alien plant species is very low.•The highest insecticidal efficacy against the rice weevil adults has diatomaceous earth.•We suggest testing the efficacy of simultaneous use of essential oils of invasive alien plants and inert dusts.
The antimicrobial activity of hop extracts obtained from different hop genotypes were investigated against
and
. In this study the pure xanthohumol, purified β-acids rich fraction, as well as α-acids ...with β-acids rich fraction were used to test antimicrobial activity against
and
; whereby, the antimicrobial activity of different hop extracts against
was studied for the first time. Microbial susceptibility to purified hydroacetonic extracts from different hop varieties was investigated by the broth microdilution assay to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The hop hydroacetonic extracts were more effective against
than against
. Strong inverse correlations of MIC and MBC values were obtained with xanthohumol, cohumulone, n+adhumulone, colupulone and n+adlupulone contents, suggesting that the identified chemical hop compounds are directly responsible for antimicrobial effects. Moreover, the effect of the growth medium strength on the MIC values of hop extracts against
was systematically investigated for the first time. The current study also reveals the effect of different hop extracts on
, which responds to their presence by lag phase extension and generation time prolongation.
In this study, a combined three-factors-three-level Box-Behnken design with a response surface methodology was used to optimize the ultrasound-assisted extraction of bound phenolic acids from ...coriander fruits. Temperature (X1, 20-60 °C), sonication time (X2, 15-45 min) and NaOH concentration (X3, 2-4 M) were studied as independent variables in order to obtain the optimal extraction conditions. For this purpose, a two-step analytical procedure was applied: first, alkaline hydrolysis and extraction under the influence of ultrasound was performed followed by a clean-up step using solid-phase extraction method. After derivatisation, the extracted phenolic acids were analysed using GC-MS. The interrelationship between the dependent and operational variables were well fitted (R2 >0.90) to the quadratic term models. The results obtained in this study confirmed that studied factors had a significant influence on phenolic acids extraction recovery. In favour of maximum extraction yields, the following experimental conditions are suggested: a sonication time of 17.4 min at 35.3°C and with a NaOH concentration of 2.02 M. These results can be utilized for further isolation of active phenolic compounds from other parts of coriander plant as well as for phenolic acids study over various plant materials from the Apiaceae family.
Camelina sativa is an alternative, low input oilseed crop with oil of high nutritional value. In Slovenia, C. sativa landrace has been grown by local farmers in the Koroška region since the middle of ...the 20th century. In our study, we determined oil and glucosinolate content (GLS) of camelina seed and free fatty acid (FFA), peroxide value (PV), iodine value (IV), tocopherol contents (T), and fatty acid profile of camelina oil from ten locations over three consecutive growing seasons. The oil content ranged from 28.78 to 40.21%, while IV, PV, and FFA fell into a range that makes this oil useful in various nutritional applications. Camelina was remarkably rich in essential n − 3 α‐linolenic acid (33.32–37.65%) and γ‐T (532–798 mg/kg) in oil, and GLS (16.39–41.43 µmol/g) in seed. Due to observed variability, it seems that the seed and oil characteristics of C. sativa landrace are affected by the local environmental conditions at a specific farm location and by variable genotypes between farms as a result of a more than half a century of environmental selection.
Practical applications: Camelina sativa landrace in Koroška, Slovenia has a long history. The agricultural environment together with the traditional diet of this region ensures preservation of this landrace and limits diffusion of modern hybrids. This plant variety has not been characterized yet. The important seed and oil quality parameters presented in this work will be useful for the determination of the nutritional value of the oil, recognizing Slovenian camelina oil as a unique vegetable oil with specific geographic origin as well as focal point for plant breeders.
Ten farm locations in Koroška region (black circles), Slovenia and Europe.
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