查看更多>>摘要：? 2022 Elsevier B.V.3D printing food materials Daylight Magna Hard Black resin (DMHB resin) and polyethylene terephthalate (PET) are widely used in food industry. During contact with microorganisms, a microbial adhesion and biofilm formation is formed and which would be responsible for serious health risks. Therefore, the present study aimed to investigate the effect of thymol and carvacrol on the physicochemical characteristics of DMHB and PET using the contact angle method. Furthermore, the biofilm formation of Bacillus subtilis and Escherichia coli on 3D printing materials studied was done. In addition, the antibiofilm effect of tow naturally compounds tested against the bacteria studied was investigated. The results of the contact angle measurements showed a significant change in the physicochemical properties of both surfaces after treatment (p < 0.05). The environmental scanning electron microscopy (ESEM) analysis showed that both studied bacteria were able to induce biofilm formation on the DMHB with a percentage of 86.57% and 91.47% for E. coli and B. subtilis respectively. Regarding the PET, it is noted that the biofilm formation is favorable with B. subtilis (78.05%) and unfavorable with E. coli (0%). For the antibiofilm effect, the results showed that a minimum concentration SubCMI = 0.14 mg/mL for carvacrol and SubCMI = 0.039 mg/mL for thymol was sufficient to obtain better inhibition of biofilm formation. Indeed, these naturally compounds significantly reduced the amount of biofilm of B. subtilis and E. coli by up to 90% on both supports studied (p < 0.05). In the light of these findings, we can deduce that it is recommended to incorporate the studied major compounds into the composition of PET and resin materials in order to use them in the food industry.
查看更多>>摘要：? 2022 Elsevier B.V.The extraction efficiency, recovery, quantification, and stability of isoflavones (daidzein, genistein and puerarin) from the wastes /by-products of kudzu roots and soy molasses were evaluated by using natural deep eutectic solvents (NADESs) coupled with ultrasound-assisted extraction. The NADES extraction was compared with the conventional Soxhlet extraction technique, and the extracted isoflavones were quantified using HPLC-UV/Vis. Results showed extractability of puerarin to be significantly increased (p < 0.0001) in proportion to the increased water concentration of NADES (9.7 ± 0.2, 12.6 ± 0.2, and 14.8 ± 0.3 mg/g in NADESs containing 10%, 20%, and 30% water, respectively). Despite having less isoflavone content, kudzu roots and soy molasses extracts obtained using NADES exhibited higher antioxidant activity when compared with methanolic extracts. Further, NADES extracts also markedly reduced the degradation degree of isoflavones. The results of this investigation support the use of green extraction techniques to obtain value-added components like isoflavones from wastes/by-products like that of kudzu roots and soy molasses, which are envisaged to find future potential applications in the food and pharmaceutical industries.
查看更多>>摘要：? 2022 The AuthorsOil palm waste is a potential source of renewable energy and also of bioactive compounds. In the present study, we analysed oil palm trunk sap (OPTS) squeezed from different parts of the trunk stored for different times and measured the reactive oxygen species (ROS) scavenging capacity using the electron spin resonance (ESR) spin trapping method using 5-(2,2-dimethyl-1,3-propoxycyclophosphoryl)?5-methyl-1-pyrroline-N-oxide (CYPMPO) as the spin trapping reagent. The highest alkoxyl radical (RO?), hydroxyl radical (?OH) and singlet oxygen (1O2) scavenging capacities were found in OPTS squeezed from the middle and top parts of the oil palm trunk. OPTS from the bottom part exhibited a lower ROS scavenging capacity than the other parts. The highest scavenging capacity for RO? was found in OPTS from the middle part of the trunk (10.38 mM Trolox eq./mL), similar to that of green tea (12.42 mM Trolox eq./mL). The scavenging capacities for ?OH of OPTS from the middle, top, and bottom parts of the trunk were 4779, 3729 and 1920 mM mannitol eq./mL, respectively, compared with 6594 mM mannitol eq./mL for blackberry. The highest 1O2 scavenging capacity of 228 mM GSH eq./mL was exhibited by OPTS from the top part of the trunk, which was higher than that of the green tea, blackberry, black tea, aloe and cucumber used as standards. The ROS scavenging capacity of OPTS measured by ESR was correlated with the corresponding values from the oxygen radical absorbance capacity (ORAC) assay. The antioxidant activity of OPTS decreased with storage time after the OPT was felled. The strong ROS scavenging capacity of OPTS makes it a potential source of bioactive compounds for use in pharmacological, cosmetic, chemical and functional food applications.
查看更多>>摘要：? 2022 Elsevier B.V.High-valued disaccharide laminaribiose, derived from two glucose units, is widely used in the pharmaceutical, cosmetic and food industries. The technology for laminaribiose synthesis from non-food feedstock cellulose instead of sucrose, glucose and starch was developed. First, we investigated a two-enzyme cascade converting cellobiose to laminaribiose by cellobiose phosphorylase and laminaribiose phosphorylase and 0.47 mol/mol cellobiose yield was obtained with cellobiose. An in vitro enzymatic cascade composed of cellobiohydrolase, cellodextrin phosphorylase, cellobiose phosphorylase and laminaribiose phosphorylase was designed to synthesize laminaribiose from cellulose. Laminaribiose production reached 2.35 and 1.23 g/L in pathways I & II, respectively. Furthermore, another multienzyme cascade was designed to eliminate the imbalance of glucose and glucose-1-p supply and laminaribiose yield finally reached 72% of that yield from cellobiose. This in vitro enzymatic cascades for laminaribiose biosynthesis not only widen the utilization of the non-food cellulose, but also provide a model that improves the economy of lignocellulosic biorefineries.
查看更多>>摘要：? 2022 Elsevier B.V.With the proposal of the Paris Climate Agreement and double carbon policy, production enterprise is now facing green and low-carbon transformation. To promote green and low-carbon development, optimizing the production process and improving utilization rate of raw materials for the reduction of production cost is an significant technological path for the plant extract industry. Thus, the aim of this work was to develop a consecutive extraction process of pectin and hesperidin with lower cost and higher purity, as well as better properties of extract. The process parameters will be put forward through single-factor experiments, Plackett-Burman design and Box-Behnken design. The experimental results showed that the consecutive extraction process was effective and feasible. Pectin with excellent properties was obtained, and the solid-liquid ratio of extraction process parameters of hesperidin was reduced to 1:8 (g: mL). The problems of environmental pollution and high energy consumption in traditional extraction could be solved. The consecutive extraction process, an innovative, economic and environmental-friendly process, may be realized easily in industrial application. At the same time, the consecutive extraction process mechanism was revealed with the help of microscopy analysis of the plant tissue structure. The results demonstrated that preferential extraction of pectin process was helpful for the exposure and dissolution of hesperidin crystallization in cells and thus can improve extraction efficiency of hesperidin. The purity of the obtained hesperidin was up to 91.7%, which can be further purified depending on application requirements. A large amount of pectin was obtained (23.3% ± 0.5% yield), and the pectin has superior gel-property, strong antioxidant activity and certain antibacterial activity. The pectin and hesperidin obtained will have better application prospects in medicine and food because of their unique characteristics.
查看更多>>摘要：? 2022 Elsevier B.V.Five Lignin/Polyethylene Glycol (L-PEG) film-forming agents with different lignin contents were prepared using industrial Alkali Lignin (AL) and Polyethylene Glycol (PEG) as the main raw materials. FI-IR and 1H NMR analysis demonstrated the introduction of large amounts of polyethylene chains in lignin molecules. The prepared L-PEGs could be dispersed in water to form a stable nanoemulsion with a particle size of 131–232 nm and a zeta potential of ? 27.22~? 38.64 mV. After L-PEGs drying into film, the obtained films can swell rapidly in water, with a swelling rate of 183.3–257.6%. The swollen wet film dissolved slowly in water with a dissolution rate of 42.3–57.1% in 14 days. The 5% flowable concentrate for seed coating (FS) of chlorantraniliprole was prepared by using L-PEG as a film-forming agent. The storage stability at elevated temperature experiment showed that the FS had good storage stability. The coating experiment showed that the FS had good coating performance, with film forming time less than 4 min, coating uniformity higher than 93.3%, and shedding rate lower than 7.67%. The pot experiment showed that the germination percentage of coated maize (Zea mays L.) seeds increased from 86.67% to over 93.33%, which could promote the growth of seedlings.
查看更多>>摘要：? 2022The two-spotted spider mites, Tetranychus urticae Koch (Acari: Tetranychidae), are one of the most important and destructive agricultural arthropod pests owing to their global distribution and resistance problem to synthetic pesticides. In the present study, miticidal activity and repellency of thirty commercial-grade essential oils via a contact bioassay and two-choice test against the adults of the mites were examined. Positive correlations between the miticidal activity and repellency were observed, as several oils exhibited notable toxicity and repellent activity comparable to a conventional pesticide, bifenthrin, based on their 95% confidence limits of LD50 values. Among the oils tested, geranium oil had the least LD50 (0.089 mg/cm2) and repellency concentration (RC50, 0.659 mg/mL), but it was not statistically different from other active oils including cedarwood, cinnamon, citronella, ginger, and lemongrass oils. About three-quarters of the oils showed increased repellency when they were mixed with vanillin, as the average repellency of 30 oils was significantly increased to 86.9 ± 2.1% from 62.1 ± 3.9% at 6.7 mg/mL application (p < 0.05). To understand the underlying mechanism of increased repellent activity of the mixtures, GC-MS analyses through an SPME collection of volatile compounds of ginger oil were conducted. No apparent difference in the aerial amounts of major constituents including (-)-zingiberene, the most abundant compound, was observed, suggesting the volatility of active components was not manipulated by the addition of vanillin.
查看更多>>摘要：? 2022 The AuthorsDespite the pharmaceutical importance of hypericin as a drug lead molecule in various medical applications, the hypericin biosynthesis pathway is not known. Herein, we report on the ability to reversibly inhibit hypericin biosynthesis via impairing the dark glands that synthesize/accumulate hypericin, and reveal the correlation between important genes and hypericin biosynthesis. The number and size of dark glands were significantly reduced in shoots regenerated from St. John's wort (Hypericum perforatum L.) root explants on medium containing sublethal level (5 μM) of glyphosate (N-(Phosphonomethyl)glycine). Ultra-Performance liquid chromatography (UPLC) system coupled with photodiode array (PDA) and fluorescence (FLR) analysis revealed that naphthodianthrones and their putative precursors i.e., emodin and bisanthrones were significantly inhibited in the presence of glyphosate, and these compounds could be fully recovered by withdrawing glyphosate, whereas phenolic compounds and phloroglucinols remain mostly unaffected. The expression of polyketide synthases (HpPKS2 and HpOKS) and phenolic oxidative coupling proteins (HpPOCP2, HpPOCP1 and HpPOCP3) were down-regulated upon glyphosate treatment and up-regulated after glyphosate withdrawal, highlighting the link between these genes and hypericin biosynthesis.
Albuquerque B.N.D.L.De Lira Pimentel C.S.Lino Da Rocha S.K.Farias De Aguiar J.C.R.D.O....
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查看更多>>摘要：? 2022 Elsevier B.V.The present study compared the chromatographic profile of oils from P. corcovadensis leaves obtained through hydrodistillation, maceration, supercritical fluid, headspace, steam distillation and ultrasound to determine the best method for the obtainment of β-germacrene-D-4-ol. The oviposition deterrent and larvicidal activities of this compound were carried out. The main compounds identified in the oils obtained using these methods were terpinolene, 1-butyl-3,4-methylenedioxybenzene, trans-caryophyllene and β-germacrene-D-4-ol, the proportions of which varied with the extraction method employed. Steam distillation (26.48 ± 0.37%), maceration (25.26 ± 0.39%) and supercritical fluid (24.38 ± 0.47%) were the best methods for extracting β-germacrene-D-4-ol. The oil obtained by maceration had the highest yield and was therefore chosen for the isolation of β-germacrene-D-4-ol. Larvicidal and oviposition assays of isolated compound and the oil obtained by maceration were performed with A. aegypti. Larvicidal activity (LC50) were 18.23 ± 1.19 ppm for β-germacrene-D-4-ol and 6.71 ± 0.16 ppm for the oil. The compound and oil also exhibited oviposition deterrence activity against the mosquito at concentrations of 5, 10 and 50 ppm. Moreover, it could be assumed that the sesquiterpene β-germacrene-D-4-ol achieves oviposition deterrence by interacting with odorant-binding protein 1 (OBP1) in Aedes aegypti, as the highest FitScore was found for this macromolecular target. This suggests how mosquito identifies β-germacrene-D-4-ol at the oviposition site. The findings demonstrate that β-germacrene-D-4-ol and the P. corcovadensis leaf oil obtained by maceration have considerable potential as larvicides and oviposition deterrents for the control of the A. aegypti.
查看更多>>摘要：? 2022 Elsevier B.V.Sunflower (Helianthus annuus L.) is one of the most economically important field crops grown in Bulgaria. In some cases sunflowers from different systems (IMI-SUN or ExpressSUN) are sprayed by mistake with the unappropriated herbicidal product for the growing system – IMI- or Express SUN and reverse. Then, acute or chronic phytotoxic effects (even death of the plants) may occur. In some situations, the plants mistakenly treated with the wrong herbicidal product may recover completely, or to different extents after ameliorative treatment with plant biostimulants. For this reason, two field trials in three consecutive growing seasons in 2017, 2018, and 2019 were conducted. The experiments were performed in the experimental field of the Department of Agriculture and Herbology at the Agricultural University of Plovdiv, Bulgaria. The experiments aimed to evaluate the ameliorative effect of the plant biostimulant Amino Expert? Impuls after imitation of ”mistaken” herbicide application. In the first experiment the ExpressSUN sunflower hybrid “P 64 LE 25″ was treated with imazamox, and in the second, the IMI-SUN sunflower hybrid “Bacardi” CLP (Clearfield Plus) was sprayed with tribenuron-methyl. The treatments included untreated control plots, application of imazamox (Pulsar Plus – 2.00 l ha?1), or tribenuron-methyl (Express 50 WG (water-soluble granules) - 0.04 kg ha?1 + Trend 90–0.1%) alone and variants with the ameliorative supplication of plant biostimulant four days after the herbicidal intervention. After the application of the plant biostimulant Amino Expert Impuls for ameliorative treatment, the plants from both cropping systems overcome the herbicide stress to different extents. The Chlorophylls (a and b) and carotenoids as well as net photosynthetic rate were higher for the untreated plants from both technologies. For the treatments where plant biostimulant application was used, an increase of the parameters sunflower head diameter, plant height, seed yield, absolute seed mass, as well as seed oil content were recorded. The obtained results showed that the significant results are in favor of ExpressSun technology. In the event of errors in the application of herbicides in these two cropping systems, the consequences are much more corrective in cases where tribenuron-methyl-tolerant sunflower is treated with Pulsar Plus than if IMI-SUN sunflower is treated with the herbicide Express 50 WG + Trend 90.
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