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1.
Sci Rep ; 14(1): 16285, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009620

RESUMO

Invasive alien species implications in ecological threats are attributed to their unique characteristics that are linked to their invasion. Veronica persica (Plantaginaceae family) is an alien weed species in Egypt. Regardless of its widespread globally in various regions, the growth traits and behavior of V. persica remain poorly understood. The comprehensive analysis, reveals the optimal germination (Gmax) was detected at 10/20 °C, 15/20 °C, and 20/25 °C at the moderate temperature regimes. The rapid germination rate (G rate) peaked at 10/20 °C regime, with a rate of 0.376 per day. Furthermore, under stress conditions, V. persica has 50% germination inhibition (G50) and 50% of growth inhibition occurred at - 0.91 MPa and 0.75 MPa of osmotic pressure and 3225.81 ppm and 2677.1 ppm of salt stress (NaCl) respectively. The germination ranged from 6 to 9 pH, with the highest germination percentage occurring at a pH of 7 & 8, reaching 88.75% compared to the control group. There is a strong interaction effect between habitats and plant stages, the plant stages and habitats have significant effects (p ≤ 0.00) on V. persica growth. There was high and moderate plasticity in the response of morphological and growth features between stages. During the seedling-juvenile interval and the juvenile-flowering stages, respectively, there was a noticeable increase in both Relative Growth Rate and Net Assimilation Rate. Demographic surveys identified approximately 24 species across 11 families associated with V. persica in invaded areas. The Sorenson indices of qualitative index exhibited high similarity values in the invaded sites by (82.35%) compared to (72.72%) in non-invaded sites. However, interactions with native communities were reflected in lower richness, diversity, and evenness, displaying slightly higher Simpson index 1 (λ) values compared to invaded and non-invaded sites (0.043 and 0.0290) vs. (0.0207 and 0.268), in rangelands and F. carica orchards respectively. These results emphasize the substantially higher adaptability of V. persica to variable environmental conditions and abilities to invade a new community. This knowledge about invasive V. persica weeds germination and growth is itemized as the consistent predictive base for future invasion and informs strategic management priorities.


Assuntos
Germinação , Espécies Introduzidas , Veronica , Veronica/crescimento & desenvolvimento , Temperatura , Ecossistema , Plantas Daninhas/crescimento & desenvolvimento , Egito
2.
Sci Rep ; 14(1): 10159, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38698043

RESUMO

Invasive alien species are becoming more and more prevalent worldwide, Erigeron bonariensis and Bidens pilosa are two invasive species of Asteraceae in Egypt. To mitigate their detrimental effects and understand their differences in invasiveness, we compared the allelopathic potentials of E. bonariensis and B. pilosa using leachates, decaying residues, and volatilization processes. Notably, the allelopathic variances in leachates were significant, influenced by plant types, concentrations, and response patterns of target plant traits, as indicated by EC50. The relative phytotoxicity of the invasive species decayed residues peaked between 20 and 25 days in the soil, with a positive correlation with concentrations and soil properties. The highest quantities of phenolic acids were chlorogenic acid and caffeic acid reaching (5.41 and 4.39 µg g-1) E. bonariensis and (4.53 and 4.46 µg g-1) B. pilosa, in leachates extracts respectively, while in the soil extract of decayed residues were coumaric acid and ferulic acid measuring (1.66 and 1.67 µg g-1) E. bonariensis and (1.47 and 1.57 µg g-1) B. pilosa, respectively. Using GC/MS analysis, the main volatile components in E. bonariensis were 1, 8 cineole (5.62%), and α-terpinene (5.43%) and iso-Caryophyllene (5.2%) which showed the greatest inhibitory effects. While B. pilosa main constituents were trans-sabinene (5.39%) and Camphene (5.11%), respectively. Finally, the high invasion level displayed from E. bonariensis (0.221) compared with B. pilosa (0.094) which correlated with the stronger allelopathic activities against plant species, and soil properties. Therefore, the allelopathic potentialities of these species are critically relevant to their invasion success.


Assuntos
Alelopatia , Bidens , Erigeron , Espécies Introduzidas , Solo , Solo/química , Erigeron/química , Egito , Hidroxibenzoatos
3.
Carbohydr Polym ; 333: 121929, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494211

RESUMO

Polymerized guluronates (polyG)-specific alginate lyase with lower polymerized mannuronates (polyM)-degrading activity, superior stability, and clear action mode is a powerful biotechnology tool for the preparation of AOSs rich in M blocks. In this study, we expressed and characterized a polyG-specific alginate lyase OUC-FaAly7 from Formosa agariphila KMM3901. OUC-FaAly7 belonging to polysaccharide lyase (PL) family 7 had highest activity (2743.7 ± 20.3 U/µmol) at 45 °C and pH 6.0. Surprisingly, its specific activity against polyG reached 8560.2 ± 76.7 U/µmol, whereas its polyM-degrading activity was nearly 0 within 10 min reaction. Suggesting that OUC-FaAly7 was a strict polyG-specific alginate lyase. Importantly, OUC-FaAly7 showed a wide range of temperature adaptations and remarkable temperature and pH stability. Its relative activity between 20 °C and 45 °C reached >90 % of the maximum activity. The minimum identifiable substrate of OUC-FaAly7 was guluronate tetrasaccharide (G4). Action process and mode showed that it was a novel alginate lyase digesting guluronate hexaose (G6), guluronate heptaose (G7), and polymerized guluronates, with the preferential generation of unsaturated guluronate pentasaccharide (UG5), although which could be further degraded into unsaturated guluronate disaccharide (UG3) and trisaccharide (UG2). This study contributes to illustrating the catalytic properties, substrate recognition, and action mode of novel polyG-specific alginate lyases.


Assuntos
Dissacarídeos , Oligossacarídeos , Especificidade por Substrato , Oligossacarídeos/metabolismo , Dissacarídeos/metabolismo , Polissacarídeo-Liases/metabolismo , Alginatos/metabolismo , Concentração de Íons de Hidrogênio , Proteínas de Bactérias/química
4.
Sci Rep ; 13(1): 11884, 2023 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-37482594

RESUMO

Citrullus lanatus var. Colocynthoide "Gurum" is an unconventional crop that can be utilized as a new source of edible oil and has the ability to grow in a variety of harsh conditions. To mitigate the adverse effects of salinity on seed germination and plant performance of C. lanatus, seeds were primed in the aqueous extracts of the seaweed Ulva lactuca before planting under greenhouse conditions. The aqueous extract of U. lactuca at 8% w/v led to maximal seed germination percentage and seedling growth of C. lanatus. Moreover, U. lactuca extract counteracted the negative effects of salt stress on the plant by significantly increasing the activity of SOD, CAT, and POD. The bioactive components of U. lactuca, e.g. glycine betaine and phenolic compounds can account for such beneficial role of algal extract on C. lanatus. Thus, priming of C. lanatus seeds in U. lactuca extract with various concentrations of U. lactuca extract can be employed as an effective practice for successful seed germination, improved plant growth and enhanced salt resistance, probably as a result of increased antioxidant enzymes activity and photosynthetic pigments.


Assuntos
Citrullus , Germinação , Salinidade , Sementes , Plântula , Antioxidantes/farmacologia
5.
Food Chem X ; 18: 100668, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37091516

RESUMO

Myrosinase is a key tool for the fast and efficient preparation of sulforaphane which is one of the prominent natural ingredients found in brassicaceous vegetables. Here, the glucoraphanin-hydrolyzing activity of a Yarrowia lipolytica 20-8 harboring myrosinase reached 73.28 U/g dry cell weight, indicating that it had a potential application in sulforaphane preparation from glucoraphanin. An efficient and reusable process for sulforaphane preparation via myrosinase produced by Y. lipolytica 20-8 was constructed. In detail, as high as 10.32 mg sulforaphane could be produced from 1 g broccoli seed under the reaction of 40 U yeast whole-cell catalyst within 15 min with the conversion efficiency of 99.86%. Moreover, when the yeast whole-cell catalyst was reused 7 and 10 times, as high as 92.53% and 87.56% of sulforaphene yield of the initial level could be retained, respectively. Therefore, this yeast whole-cell is a potent biocatalyst for the efficient and reusable preparation of sulforaphane.

6.
Foods ; 11(7)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35407112

RESUMO

Fucoidan is one of the main polysaccharides of brown algae and echinoderm, which has nutritional and pharmacological functions. Due to the low molecular weight and exposure of more sulfate groups, oligo-fucoidan or fucoidan oligosaccharides have potential for broader applications. In this research, a novel endo-α-1,4-L-fucoidanase OUC-FaFcn1 which can degrade fucoidan into oligo-fucoidan was discovered from the fucoidan-digesting strain Flavobacterium algicola 12,076. OUC-FaFcn1 belongs to glycoside hydrolases (GH) family 107 and shows highest activity at 40 °C and pH 9.0. It can degrade the α-1,4 glycosidic bond, instead of α-1,3 glycosidic bond, of the fucoidan with a random tangent way to generate the principal product of disaccharide, which accounts for 49.4% of the total products. Therefore, OUC-FaFcn1 is a promising bio-catalyst for the preparation of fucoidan-derived disaccharide. These results further enrich the resource library of fucoidanase and provide the basis for the directional preparation of fucoidan-derived oligosaccharide with specific polymerization.

7.
J Agric Food Chem ; 70(7): 2303-2311, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35112855

RESUMO

Myrosinase is a biotechnological tool for the preparation of sulforaphane and sulforaphene with a variety of excellent biological activities. In this study, a gene encoding the novel glycoside hydrolase family 3 (GH3) myrosinase Rmyr from Rahnella inusitata was heterologously expressed in Escherichia coli BL21 (DE3). The purified Rmyr shows the highest activity at 40 °C and pH 7.0; meanwhile, its half-life at 30 °C reaches 12 days, indicating its excellent stability. Its sinigrin-, glucoraphenin-, and glucoraphanin-hydrolyzing activities were 12.73, 4.81, and 6.99 U/mg, respectively. Rmyr could efficiently degrade the radish seed-derived glucoraphenin and the broccoli seed-derived glucoraphanin into sulforaphene and sulforaphane within 10 min with the highest yields of 5.07 mg/g radish seeds and 9.56 mg/g broccoli seeds, respectively. The highest conversion efficiencies of sulforaphane from glucoraphanin and sulforaphene from glucoraphenin reached up to 92.48 and 97.84%, respectively. Therefore, Rmyr is a promising and potent biocatalyst for efficient and large-scale preparation of sulforaphane and sulforaphene.


Assuntos
Glucosinolatos , Imidoésteres , Glucosinolatos/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Imidoésteres/metabolismo , Isotiocianatos/química , Rahnella , Sulfóxidos
8.
J Environ Sci Health B ; 47(5): 390-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22424063

RESUMO

Efficiency of different tank-mixed additives with bentazon at half rate was investigated on (Malva parviflora) and other broad leaf weeds compared with bentazon at the full recommended rate without additives in peas in open field. All the tested additives enhanced the efficiency of bentazon at the half rate. Nonyl phenol and toximol S proved to be the most effective additives in comparison with the full rate treatment. The tested treatments did not show any significant effect on chlorophyll content and soil microorganisms. Bentazon residues were determined in certain treatments to investigate the effect of the tested additives on bentazon deposition. Samples were extracted using QuEChERS method and residues were determined using LC-MS/MS. Residues after 24 hours in the half rate treatment reached 4 times lower than the Maximum Residues Limit (MRL) (0.11 mg kg(-1)), compared to the full rate treatment (0.51 mg kg(-1)), that was slightly above the MRL.


Assuntos
Benzotiadiazinas/farmacologia , Herbicidas/farmacologia , Plantas Daninhas/efeitos dos fármacos , Controle de Plantas Daninhas/métodos , Pisum sativum/crescimento & desenvolvimento , Controle de Plantas Daninhas/instrumentação
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