• Research in Plant Disease
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• v.25 no.3
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• pp.136-142
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• 2019

Drought stress is considered as one of major abiotic stresses; it leads to reduce plant growth and crop productivity. In this study, we selected bacterial strains for alleviating drought stress in chili pepper plants. As drought-tolerant bacteria, 28 among 447 strains were pre-selected by in vitro assays including growth in drought condition with polyethylene glycol and plant growth-promoting traits including production of 1-aminocyclopropane-1-carboxylate deaminase, indole-3-acetic acid and exopolysaccharide. Sequentially, 7 among pre-selected 28 strains were screened based on relative water content (RWC); GLC02 and KJ40, among seven strains were finally selected by RWC and malondialdehyde (MDA) in planta trials under an artificial drought condition by polyethylene glycol solution. Two strains GLC02 and KJ40 reduced drought stress in a natural drought condition as well as an artificial condition. Strains GLC02 or KJ40 increased shoot fresh weight, chlorophyll and stomatal conductance while they decreased MDA in chili pepper plants under a natural drought condition. However, two strains did not show biocontrol activity against diseases caused by Phytophthora capsici and Xanthomonas campestris pv. vesicatoria in chili pepper plants. Taken together, strains GLC02 or KJ40 can be used as bio-fertilizer for alleviation of drought stress in chili pepper plants.

• Journal of Microbiology and Biotechnology
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• v.21 no.1
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• pp.28-36
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• 2011

Diblock copolymers composed of poly(${\varepsilon}$-caprolactone) (PCL) and poly(N,N-dimethylamino-2-ethyl methacrylate) (PDMAEMA), or methoxy polyethylene glycol(PEG), were synthesized via a combination of ring-opening polymerization and atom-transfer radical polymerization in order to prepare polymeric nanoparticles as an antifungal drug carrier. Amphotericin B (AmB), a natural antibiotic, was incorporated into the polymeric nanoparticles. The physical properties of AmB-incorporated polymeric nanoparticles with PCL-b-PDMAEMA and PCL-b-PEG were studied in relation to morphology and particle size. In the aggregation state study, AmB-incorporated PCL-b- PDMAEMA nanoparticles exhibited a monomeric state pattern of free AmB, whereas AmB-incorporated PCL-b- PEG nanoparticles displayed an aggregated pattern. In in vitro hemolysis tests with human red blood cells, AmBincorporated PCL-b-PDMAEMA nanoparticles were seen to be 10 times less cytotoxic than free AmB (5 ${\mu}g$/ml). In addition, an improved antifungal activity of AmBincorporated polymeric nanoparticles was observed through antifungal activity tests using Candida albicans, whereas polymeric nanoparticles themselves were seen not to affect activity. Finally, in vitro AmB release studies were conducted, proving the potential of AmB-incorporated PCL-b-PDMAEMA nanoparticles as a new formulation candidate for AmB.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1429-1437
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• 2003

Browse tree legume leaves from Acacia spp (A. nilotica, A. tortilis, A. polyacantha), Dichrostachys sp, Flagea villosa, Piliostigma thonningii, Harrisonia sp were evaluated for nutritive potential (chemical compositions and degradability characteristics) compared to Gliricidia sepium. Effect of tannins anti-nutritive activity on digestibility was also assessed by polyethylene glycol (PEG) tannin bioassay. Crude protein (CP), ash, neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) differed (p<0.05) between legume foliages. Mean CP, ash, NDF, ADF and ADL for fodder species tested were 158, 92, 385, 145, and 100 g/kg DM, respectively. CP ranged from 115 (P. thonningii) to 205 g/kg DM (G. sepium). Acacia spp had moderate CP values (g/kg DM) of 144 (A. nilotica), to high CP in A. tortilis (188) and A. polyacantha (194) comparable to G. sepium. The forages had relatively lower fiber compositions. A. nilotica had (p<0.05) lowest NDF, ADF and ADL (182, 68 and 44) compared to P. thonningii (619, 196 and 130) g/kg DM, respectively. Except G. sepium, all fodder species had detectable high phenolic and tannin contents greater than 5% DM, an upper beneficial level in animal feeding and nutrition. Mean total phenolics (TP), total tannins (TT) and condensed tannins (CT) (or proanthocyanidins) for fodder species tested were 139, 113 and 43 mg/g DM, respectively. F. villosa had (p<0.05) lowest TP and TT of 65 and 56 mg/g DM, respectively, compared to A. nilotica (237 and 236 mg/g DM, respectively). The CT varied (p<0.05) from 6 (F. villosa) to 74 mg/g DM (Dichrostachys sp). In vitro organic matter (OM) degradability (OMD) differed (p<0.05) between fodder species. G. sepium had (p<0.05) high degradability potential compared to A. polyacantha that had (p<0.05) the lowest OMD values. Forage degradability ranked: G. sepium>A. nilotica>P. thonningi>F. villosa>Dichrostachys sp>A. tortilis>A. polyacantha. Addition of PEG resulted to (p<0.05) improvement in in vitro OM digestibility (IVD). Increase in IVD was mainly due to binding action of PEG on tannins; and represents potential nutritive values previously depressed by tannins anti-nutritive activity. Browse fodder has potential as sources of ruminal nitrogen especially for ruminants consuming low quality roughages due to high protein, lower fiber compositions and high potential digestibility. However, utilization of browse supplements in ruminants is hampered by high phenolic and tannin contents. Deactivation of tannin anti-nutritive activity, possibly by feeding tanniniferous browse with other readily available nitrogen sources to dilute tannin anti-nutritive activity could improve utilization of browse fodder supplements. Further studies are needed to assess browse fodder palatability and intake, and their effect on growth performance in ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.880-886
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• 2007

Ensiled or oven-dried green tea by-products (GTB) were evaluated in goats for their nutritive potential as protein feedstuffs based on in vitro and in vivo digestibility. To elucidate the effects of tea tannin on in vitro digestibility, polyethylene glycol (PEG) was used as a tannin binding agent. Both ensiled and dried GTB contained 31.9 to 32.6% of crude protein (CP) on a dry matter (DM) basis. Phenolics and tannins in soybean meal and alfalfa hay were low or not detected, but they were high in both ensiled and dried GTB (7.3-10.1% DM as total extractable tannins). In vitro protein digestibility in the rumen ranked: soybean meal>alfalfa hay cube>ensiled GTB = dried GTB. The protein digestibility post-ruminally of these feedstuffs showed a similar trend to that in the rumen, but the digestibility of ensiled GTB was significantly higher than that of dried GTB. Addition of PEG improved the in vitro protein digestibility of both kinds of GTB in the rumen and post-ruminally, indicating that tannins suppressed the potential protein digestibility of GTB. The increased protein digestibility by PEG addition was not significantly different between ensiled and dried GTB in the rumen, but the percentage increment of ensiled GTB was higher than dried GTB post-ruminally. In the in vivo digestibility trial, ensiled and dried GTB were offered to goats as partial substitutes for soybean meal and alfalfa hay cubes. Offering both GTB to goats as 5-10% on a DM basis did not affect nutrient digestibility, ruminal pH, volatile fatty acids, and ammonia concentration. However, the eating time of the GTB-incorporated diet was longer than that of the basal diet. It took 1.4 and 1.6 times longer than the control diet, to eat the diet completely when GTB silage was offered at 5 and 10% levels, respectively, of the total diet. These results show that ensiled and dried GTB are useful as partial substitutes for soybean meal and alfalfa hay cubes for goats with respect to nutritive value. Because of lessened palatability, it is recommended that GTB be incorporated into the diet at 5% on a DM basis.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.25 no.3
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• pp.163-179
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• 2022

Although functional gastrointestinal disorders (FGIDs) are very common in pediatric patients, there is a scarcity of published epidemiologic data, characteristics, and management patterns from Saudi Arabia, which is the 2nd largest Arabic country in terms of area and the 6th largest Arabic country in terms of population, with 10% of its population aged <5 years. Functional constipation (FC) is an FGID that has shown a rising prevalence among Saudi infants and children in the last few years, which urges us to update our clinical practices. Nine pediatric consultants attended two advisory board meetings to discuss and address current challenges, provide solutions, and reach a Saudi national consensus for the management of pediatric constipation. The pediatric consultants agreed that pediatricians should pay attention to any alarming signs (red flags) found during history taking or physical examinations. They also agreed that the Rome IV criteria are the gold standard for the diagnosis of pediatric FC. Different therapeutic options are available for pediatric patients with FC. Dietary treatment is recommended for infants with constipation for up to six months of age. When non-pharmacological interventions fail to improve FC symptoms, pharmacological treatment with laxatives is indicated. First, the treatment is aimed at disimpaction to remove fecal masses. This is achieved by administering a high dose of oral polyethylene glycol (PEG) or lactulose for a few days. Subsequently, maintenance therapy with PEG should be initiated to prevent the re-accumulation of feces. In addition to PEG, several other options may be used, such as Mg-rich formulas or stimulant laxatives. However, rectal enemas and suppositories are usually reserved for cases that require acute pain relief. In contrast, infant formulas that contain prebiotics or probiotics have not been shown to be effective in infant constipation, while the use of partially hydrolyzed formula is inconclusive. These clinical practice recommendations are intended to be adopted by pediatricians and primary care physicians across Saudi Arabia.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.13 no.1
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• pp.36-43
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• 2010

Purpose: The aim of this study was to evaluate the clinical features and factors contributing to treatment outcome for chronic functional constipation in children. Methods: We analyzed the medical records of patients with constipation, who visited the inpatient or outpatient clinic of the Department of Pediatrics of Pusan National University Hospital, between January 1998 and December 2007. The clinical features, outcomes, and factors affecting the treatment response according to the main drug (lactulose vs. PEG 4000) were analyzed retrospectively. Results: Two hundred forty children (142 males and 98 females) were enrolled in this study. The mean age was 51.2${\pm}$37.9 months. The duration of symptoms was 32.6${\pm}$33.7 months. The accompanying symptoms were as follows: encopresis, 91 (30.4%); abdominal pain, 76 (31.6%); and blood-tinged stool, 37 (15.4%). The treatment response was achieved earlier in females (p<0.001), patients with accompanying symptoms (p<0.05), and patients treated with PEG 4000 (p=0.001). The duration of symptoms (p<0.05) and stool frequency before treatment (p<0.05) were related to a delayed treatment response. Relapse occurred in 7 children, all of whom were treated successfully later. Conclusion: Factors contributing to treatment response are female gender, accompanying symptoms, duration of symptoms, and stool frequency before treatment. PEG 4000 is superior to lactulose in response time and taken into consideration as a primary drug for the treatment of functional constipation of children. Early treatment and sufficient treatment time may also be important factors to achieve an early response and prevent relapse.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.460-465
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• 1990

Regeneration of protoplast was effective by preincubating spore suspension containing 30$\mu g$/ml of 2-DG for 4 hours, and CBE medium containing casamino acid, bovine serum albumin, ergosterol and myoinositol was found to be more efficient than any other regeneration medium tested in this experiment. The regeneration frequency was about 30%. Optimal conditions for conidial protoplast fusion were obtained by treatment of protoplasts with 10 mM $CaCl_2$ and 30% polyethylene glycol 4000 (pH 7.5) as fusogenic agent at $37^{\circ}C$ for 10 minutes. The fusion frequency was $8.2\times 10^{-4}$. The higher productivity of enzyme of fusant FWN-56 was achived: 2.3-fold for CMCase, 1.5-fold for avicelase, 1.8-fold for $\beta$-glucosidase and 2.5-fold for xylanase compared to that obtained in two parental strains. The genetic stability of fusant after maintenance on minimal medium for more than 4 weeks was high because segregant rate was below 1%. The conidial DNA content of fusant was 1.4-1.6 times higher than that of the parental strains, The nucleus size of fusants were also higher than that of each parental strains.

• The Korean Journal of Mycology
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• v.20 no.1
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• pp.44-50
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• 1992

The protoplast formation of Rhizoctonia solani in the fast growing anastomosis groups (AGs) 1 and 4, the intermediate AG-2 and AG-5, and the slow AG-3 yielded the most, moderate and the least in that order, respectively. Sclerotia formation varied with AGs. A high yield of protoplasts from AGs was obtained with a combined lytic enzyme system containing cellulase 'Onozuka' R-10, macerozyme R-10 and ${\beta}-glucuronidase$. When 3g (fresh weight) of 30 hr old mycelia was incubated for 3 hr at $32^{\circ}C$ with the enzyme mixture in 0.6 M mannitol, maximum protoplasts were obtained in the five AGs. A protoplast fusion between sclerotia forming AG-1 inactivated with heat and non-forming AG-5 was induced by polyethylene glycol and ${Ca}^{2+}$. Seven fusants obtained were based on characteristics of colony and sclerotium formation on culture plates. The fusants were confirmed by isozyme patterns of esterase and killing reaction between AG-1 and a fusant F1501.

• Journal of Pharmaceutical Investigation
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• v.32 no.3
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• pp.191-197
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• 2002

Polymer based physical mixtures or solid dispersions containing solubilizing compositions[OA, tween80 and SLS] were prepared using a spray-dryer. Lovastatin(LOS), simvastatin(SIMS), aceclofenac(AFC) and cisapride(CSP) were selected as poorly water-soluble drugs. Dextrin, poly(vinylalcohol) (PVA), poly(vinylpyrrolidone)(PVP) and polyethylene glycol(PEG) were chosen as solubilizing carriers for solid dispersions. The solid dispersions containing solubilizing compositions without drug were prepared without using organic solvents or tedious changes of formulation compositions. This system could be used to quickly screen the dissolution profiles of poorly water-soluble drugs by simply mixing with drugs thereafter. In case of solid dispersion containing drug, organic solvent systems could be used to solubilize model drugs. The dissolution rates of the drugs were higher when mixed with drug and solid dispersions containing solubilizing compositions. However, solid dispersions of LOS, AFC, and CSP simultaneously containing drug and solubilizing compositions in organic solvent systems were more useful than physical mixtures of drug and solid dispersions without drug except SIMS. Based on solubilizing capability of polymer based physical mixtures in gelatin hard capsules, optimal solid dispersion system of poorly water-soluble drugs could be formulated. However, it should be noted that dissolution rate of poorly water-soluble drugs were highly dependent on drug properties, solubilizing compositions and polymeric carriers.

• Membrane and Water Treatment
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• v.2 no.1
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• pp.25-37
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• 2011

PES UF membranes containing silver were prepared to impart antibacterial properties for waste water treatment. Asymmetric membranes for antibacterial application were prepared from polyethersulfone (PES) and silver nitrate ($AgNO_3$) (PES/$AgNO_3$=15/2 by weight) solution in N-Methyl-2-pyrrolidone (NMP) via simple wet phase inversion technique. These membranes were characterized by polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) of different molecular weights (1000 ppm in water) at room temperature and on operating pressure of 5 bars. It was observed that the water flux of PES-$AgNO_3$ membrane is slightly lower than virgin PES but still increased linearly with the increment of pressure applied. The morphology of the resulting membranes was examined using Field-Emission Scanning Electron Microscope (FESEM) coupled with Energy Dispersive Spectroscopy (EDS). Elemental analysis using EDS proved that silver is successfully loaded on the membrane surfaces. Due to the success of loading silver on membrane surfaces, antibacterial activities were evaluated via agar diffusion method against Escherichia coli (E.coli) and Staphylococcus aureus (S.aureus) culture. By incorporating 2 wt% of silver nitrate, PES-$AgNO_3$ showed significant inhibition ring on both E.coli and S.aureus. Filtration of E.coli solution (OD 0.31) showed satisfactory rejection data with ~100% inhibition growth after 24 hours incubation at $37^{\circ}C$. Resultant membranes also exhibit better tensile strength (compared to virgin PES) up to 71% may be due to the suggested interactions. The residual silver during fabrication was measured using ICP-MS and result showed that the residual silver content of PES-$AgNO_3$ membrane was only ~1% of the original silver added in the polymer solution. These studies have shown that PES-$AgNO_3$ UF membranes are potential in improving the filtration in water treatment.