A large area of Iran is located in arid and semi-arid regions; as a result, drought stress is a major problem for the growth of plants. Therefore, it is very important in crop productivity to ...increase plant tolerance to drought stress. Plant growth promoting rhizobacteria such as Azotobacter may enhance plant growth under drought stress conditions by different mechanisms. In this study, a total of 20 Azotobacter strains were isolated and characterized from 77 rhizosphere soil samples collected from semi-arid regions. The strains were screened for the production of siderophore and IAA, solubilization of phosphate and potassium and growth under drought stress in PEG 6000. The strains were identified by 16S rRNA gene sequencing. The efficient strains were tested on the growth of maize (Zea mays) under drought stress by using three levels of irrigation, including 80, 60 and 40 percent of field capacity in greenhouse conditions. The laboratory results revealed that Az63, Az69 and Az70 were the most effective strains in terms of phosphate and potassium solubilisation, siderophore producion and maximum growth in PEG 6000. At 40 percent of field capacity, the inoculation increased shoot dry weight, plant height, chlorophyll content, nitrogen, phosphorous and iron concentration compared to the control. Az63 and Az70 increased shoot dry weight significantly at 60 percent of field capacity.
Benih kakao (Theobroma cacao L.) merupakan benih rekalsitran yang cepat mengalami kemunduran selama penyimpanan. Penanganan benih yang tepat melalui invigorasi, dapat menjadi solusi untuk ...mempertahankan dan meningkatkan viabilitas dan vigor. Penelitian bertujuan untuk mengetahui pengaruh invigorasi dan lama penyimpanan terhadap viabilitas benih dan pertumbuhan awal bibit kakao. Bahan yang digunakan benih kakao, cocopeat, PEG 6000, NAA, GA3 dan bahan pendukung lainnya. Penelitian ini menggunakan rancangan acak lengkap faktorial yang terdiri dari dua faktor. Faktor pertama adalah jenis invigorasi dan faktor kedua adalah lama penyimpanan. Hasil penelitian menunjukkan bahwa penggunaan media cocopeat, PEG 6000, NAA dan GA3 dengan lama penyimpanan 4 minggu memberikan hasil terbaik terhadap vibilitas benih dan pertumbuhan awal bibit kakao.
Background: Droughts during the growing season are becoming increasingly common due to climate change and global warming. The study’s goal study was to assess the adaptation mechanisms of C. ...coggygria Scop. under simulated water deficit conditions using indicators characterized changes in the leaf stomatal apparatus and photosynthesizing system. Methods: The influence of osmotic polyethylene glycol 6000 on the research object C. coggygria regenerants was studied in vitro. Such indicators as morphological changes, pigment content, stomatal density and size and stomatal slit size were quantified. Result: Due to the influence of osmotic stress, there was a pigment content increase in the leaf plate on osmotic media. Stomatal density raised by 27.0-29.8% in explant cells cultivated on PEG 4.0-6.0%. Under the osmotic influence, there was a drop in the stomatal cells’ area and shape and the ratio of stomatal length to width in the regenerant leaves decreased from 1.5 to 1.0-1.1. These results indicate the adaptation of C. coggygria regenerants to stress caused by an artificial drought in vitro. The changes’ identification in the stomatal apparatus and the C. coggygria pigment ratio will accelerate the selective screening of drought-resistant plants for use in protective forestry.Background: Droughts during the growing season are becoming increasingly common due to climate change and global warming. The study’s goal study was to assess the adaptation mechanisms of C. coggygria Scop. under simulated water deficit conditions using indicators characterized changes in the leaf stomatal apparatus and photosynthesizing system.
Greengram (Vigna radiata L. Wilczek) is the third most important pulse crop. One of the main factors limiting its production and productivity is drought, in different growth stages of the crop. ...Drought stress at the seedling stage of greengram influences their adaptation at the early crop establishment phase. In this study, 200 pre-breeding lines derived from VBN(Gg) 2 X Vigna radiata var.sublobata/2 of greengram were evaluated for drought stress by in vitro screening, using Poly ethylene glycol (PEG 6000) at -0.5MPa stress level. Significant differences were observed among the genotypes, treatments and interactions for the evaluated seedling traits and stress indices, suggesting a high variability for drought tolerance in pre- breeding lines. A total of eleven tolerant and six susceptible lines were selected based on seedling vigour index, > 900.00 and < 220.00, respectively during initial screening and independent confirmation screening was carried out. The results of the present study revealed that the pre-breeding lines viz., GGISC 45, GGISC 41, GGISC 132, GGISC 125, GGISC 116, GGISC 55, GGISC 147, GGISC 17, GGISC 73, GGISC 49 and GGISC 37 were recorded with high seedling vigour index along with significant stress indices and identified as tolerant for drought. These identified tolerant lines can be further evaluated under rain-out shelter to assess their ability to withstand drought. Subsequently, the promising lines can be used for the development of drought tolerant varieties in greengram.
Hens are oviparous vertebrates and produce IgY antibodies, which is the main type of immunoglobulin in the egg yolk, and high concentrations can be obtained by using a simple method that does not ...require sophisticated equipment and reagents. The Polyethylene Glycol 6000 method allows the removal of lipids and the precipitation of IgY in two days with an approximated purity of around 80%, however during the original protocol other contaminant proteins can be precipitated. To overcome the issue of contamination with other proteins and extraction time, we optimized the previously method described by Pauly et al. (2011) by adding some changes that improved the aforementioned problems.
• Our protocol is customized by the addition of one more filtration step or one more step with PEG 6000 at 3.5% to avoid the contamination with lipids.
• Additionally, the changes in the type of agitation, centrifugation and the skip of dialysis make the method more accessible for all the laboratories.
• In summary, these modifications serve to enhance the purity, reduce the time for IgY extraction from egg yolk and make it more accessible for every basic research laboratory.
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•Silicon glass microparticles (SiMPs) induce tolerance to abiotic stresses.•Seed priming mitigated the effects of water restriction in cowpea plants.•Therefore, plants from seeds subjected to SP ...improve tolerance to water stress.
The northeast region of Brazil presents high variations in solar radiation levels and high air temperatures, impairing the growth and production of cowpea, consequently raising the need for technologies to improve the adaptation of cultivated plants. Therefore, this work aimed to promote the tolerance of cowpea (cultivar BRS Itaim) to water deficit induced by polyethylene glycol 6000 through seed conditioning with silicon glass microparticles. The experiment was performed in the field using a completely randomized 6 × 2 factorial scheme design with four replications. Seed priming (SP) consisted of six combinations of water potential (Ψw) and silicon glass microparticles (SiMPs) (T1: Ψw 0 + 0 SiMPs, T2: Ψw 0 + 200 SiMPs, T3: Ψw -0.4 + 0 SiMPs, T4: Ψw -0.4 + 200 SiMPs, T5: Ψw -0.8 + 0 SiMPs, and T6: Ψw -0.8 + 200 SiMPs) and two water replacement levels: plants with water restriction (50 % of water consumption) and without it (100 % of water consumption). Seed priming with silicon glass microparticles and polyethylene glycol 6000 attenuated the deleterious effects of water restriction in cowpea plants through water status homeostasis, osmotic adjustment, and antioxidant mechanism.
Kencur (Kaempferia galanga L.) is a plant that has a high enough rhizome selling value. Increased production can be done by expanding the land. However, cultivated land in Indonesia is generally ...dominated by dry land with limited water availability. The research objective was to obtain galanga callus that were tolerant of drought in vitro using the PEG 6000 selective agent. Randomized block design (RBD) 2 factors were repeated 3 times. PEG 6000 concentrations were 0%, 5%, 10%, 15%, 20% and NAA concentrations were 1mg/l, 1.5mg/l, 2mg/l. The parameters observed were callus morphology (texture and color), wet weight, dry weight, percentage of fresh callus, number of roots, proline content, and live callus percentage. The results showed compact textures that were green, white, and brown. Wet weight, dry weight, percentage of fresh callus, number of roots of PEG 6000 treatment resulted in a decreasing value while the proline content increased with the increase in PEG 6000 concentration. The NAA treatment at the concentration of 1mg/l produced the most roots, while the percentage value of fresh callus was inversely proportional to the value of the proline content. The lower the PEG 6000 and NAA concentrations resulted in more roots. The higher the PEG 6000 concentration and the lower the NAA concentration resulted in high the proline content. PEG 6000 20% still produced 61% living callus.
Ursolic acid is a molecule with several therapeutic applications not yet commercially explored because of its bioavailability-limiting water insolubility. To avoid this drawback, solid dispersions ...containing ursolic acid have been employed to increase water solubility. The influence of hydrophilic carriers, PEG 6000 and Poloxamer 407, and the method of preparation, fusion and solvent, were studied for ursolic acid in this work. The solid dispersions and physical mixtures were characterized by particle size, scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffractometry, differential scanning calorimetry, hot stage microscopy, water solubility and dissolution profile. Results showed that both methods and polymers used for solid dispersion preparation resulted in homogeneous powders, but the surfactant Poloxamer 407 enhanced the ursolic acid solubility in solid dispersions better than PEG 6000. With Poloxamer 407, both methods enabled complete dissolution of ursolic acid in phosphate buffer; however the solid dispersion showed higher solubility when prepared by the solvent method compared to the fusion method, 689.47μg/mL and 328.52μg/mL, respectively. For comparison, the physical mixture solubility was 248.17μg/mL. The better results achieved with the solvent method were attributed to smaller particle size, amorphic conversion of ursolic acid from its less soluble crystalline state and hydrogen bond formation between drug and carrier, whereas there was a polymorphic change caused by the fusion method. Results indicated that the solid dispersion prepared by the solvent method is an adequate approach to increasing ursolic acid solubility and dissolution, a very important step toward the development of a pharmaceutical dosage form containing ursolic acid.
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•Solvent and fusion methods produced solid dispersions of ursolic acid in PEG 6000 and Poloxamer 407.•Drugs in solid dispersions by the solvent method were converted from a crystalline to amorphous form.•Hydrogen bolding between drug and carriers could be detected for solid dispersions by the solvent method.•Fusion method caused polymorphic change in ursolic acid.•Solid dispersions with Poloxamer 407 by the solvent method improved solubility and dissolution rate of ursolic acid.
Objective: The aim of the present work was to prepare solid dispersion of ibuprofen with PEG 6000 to increase the aqueous solubility of the drug and to develop the solid dispersed ibuprofen into ...tablet formulation with the combination of a hydrophilic and hydrophobic polymer to attain controlled release of ibuprofen.
Methods: Solid dispersion of ibuprofen was prepared by melting-solvent method by varying the ratio of drug and PEG 6000. The solid dispersed ibuprofen was subjected to tablet formulation by using a hydrophilic swellable polymer-carbopol and hydrophobic non-swellable polymer-ethyl cellulose. The release of the drug from the polymer matrix was studied as the polymer ratio changes.
Results: Compatibility between drug and polymers was established from FT-IR study. The saturated solubility was found to increase in the solid dispersed formulation. The swelling index was found within the range of 90±5.43 to 137±6.41. SEM image of swollen tablet confirmed the presence of irregular and porous surface. The cumulative drug release was found to vary within the range of 68.76±3.04 to 95.33±2.34 % after 8 h of dissolution.
Conclusion: The combination of solid dispersion and application of hydrophilic and hydrophobic polymers in matrix formation can facilitate better dissolution and absorption profile with greater patient compliance.
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