Vacuum-assisted thermal drying of wastewater treatment sludge.

Sludge drying is one of the main problems of wastewater treatment plants. It is very important to facilitate the drying process in terms of drying efficiency, time duration, and cost of the processes, so that transportation and dumping of sludge will accordingly be realized effectively. In this study, vacuum assisted thermal drying was studied. Under vacuum conditions, the water content of the sludge was examined easier than at atmospheric pressure in the drying process. For this reason, in this study, time, temperature, and sludge mass surface area on drying efficiency were evaluated under two different pressure levels, such as 30 mbar and 1,000 mbar. To optimize these parameters, the Response Surface Methodology approach was utilized. Results showed that the effect of vacuum condition on sludge drying was remarkable at obtaining at least 65% of solid material ratio in sludge, which is the lowest limit value on landfilling legislation in Turkey. Data obtained from the study shows that, especially at high temperatures, contribution on sludge drying of vacuum condition is more effective in terms of drying time. A smaller sludge surface area is also found more significant on vacuum drying.Implications: Drying the sludge under low pressure shortens the drying time. It is possible to reach higher solid material ratio under low pressure. Time, temperature, and surface areas of sludge are effective parameters in vacuum drying.

False flax (Camelina sativa) seed oil as suitable ingredient for the enhancement of physicochemical and biological properties of chitosan films.

To overcome the drawbacks of synthetic films in food packaging industry, researchers are turned to natural bio-based edible films enriched with various plant additives. In current study chitosan blend films were produced by incorporating Camelina sativa seed oil at varying concentrations to chitosan matrix. The chitosan blend films were characterized both physicochemically (structural, morphological, thermal, optical and mechanical) and biologically (antimicrobial and antioxidant activity). The incorporation of C. sativa seed oil notably enhanced thermal stability, antioxidative, anti-quorum sensing and antimicrobial activity. Except elongation at break, other mechanical properties of the blend films were not affected by incorporation of C. sativa seed oil. The surface morphology of blend films was recorded as slightly rough, non-porous and fibre-free surface. As it was expected the optical transmittance in visible region was gradually decreased with increasing fraction of seed oil. Interestingly the hydrophilicity of the blend films revealed a swift increase which can be explained by the formation of micelle between glycerol and Tween 40 in blend films. This study provides valuable information for C. sativa seed oil to be used as a blending ingredient in chitosan film technology.

Detailed adsorption mechanism of plasmid DNA by newly isolated cellulose from waste flower spikes of Thypa latifolia using quantum chemical calculations.

Current study was designed to use the newly obtained cellulose from waste flower spikes of Thypa latifolia plant for plasmid DNA adsorption. Cellulose was isolated according to a previously described method including acid and base treatment, and cellulose content was recorded as 17%. T. latifolia cellulose was physicochemically characterized via FT-IR, TGA and SEM techniques. Detailed mechanism of plasmid DNA adsorption by newly isolated cellulose was described using chemical quantum calculations. To check the effect of Cu++ immobilization on the affinity of cellulose for plasmid DNA, copper ions were immobilized onto T. latifolia cellulose. pUC18 plasmid DNA was used for adsorption studies. Membranes prepared with only T. latifolia cellulose and Cu++ immobilized T. latifolia cellulose revealed different adsorption ratios as 43.9 and 86.9% respectively. This newly isolated cellulose from waste flower spikes of T. latifolia can be utilized as a suitable carrier for plasmid DNA.

Rational drug therapy education in clinical phase carried out by task-based learning.

OBJECTIVES: Irrational drug use results in drug interactions, treatment noncompliance, and drug resistance. Rational pharmacotherapy education is being implemented in many faculties of medicine. Our aim is to introduce rational pharmacotherapy education by clinicians and to evaluate task-based rational drug therapy education in the clinical context. METHODS: The Kirkpatrick's evaluation model was used for the evaluation of the program. The participants evaluated the program in terms of constituents of the program, utilization, and contribution to learning. Voluntary participants responded to the evaluation forms after the educational program. Data are evaluated using both quantitative and qualitative tools. SPSS (version 21) used for quantitative data for determining mean and standard deviation values. Descriptive qualitative analysis approach is used for the analysis of open-ended questions. RESULTS: It was revealed that the program and its components have been favorable. A total 95.9% of the students consider the education to be beneficial. Simulated patients practice and personal drug choice/problem-based learning sessions were appreciated by the students in particular. 93.9% of the students stated that all students of medicine should undergo this educational program. Among the five presentations contained in the program, "The Principles of Prescribing" received the highest points (9 ± 1.00) from participating students in general evaluation of the educational program. CONCLUSION: This study was carried out to improve task-based rational drug therapy education. According to feedback from the students concerning content, method, resource, assessment, and program design; some important changes, especially in number of facilitators and indications, are made in rational pharmacotherapy education in clinical task-based learning program.

In situ chitin isolation from body parts of a centipede and lysozyme adsorption studies.

Isolation of structurally intact chitin samples for biotechnological applications has gained much recent attention. So far, three-dimensional chitin isolates have been obtained from only diplopods and sponges. In this study, three-dimensional chitin isolates were obtained from the body parts of centipede Scolopendra sp. (antennae, head, forcipule, collum, trunk, trunk legs and last pair of legs) without leading to structural failure. FT-IR spectra of chitin isolates confirmed that chitin samples are in α allomorph. TGA, XRD and SEM analyses and lysozyme adsorption studies revealed that each chitin isolate had different thermal stability, crystallinity and surface characteristics. Among the chitin isolates, Cu(II)-immobilized forcipule chitin showed the highest affinity for lysozyme (54.1mg/g), whereas chitin from last pair of legs exhibited the lowest affinity (3.7mg/g). This study demonstrated that structurally intact chitin isolates can be obtained from the body parts of centipede Scolopendra sp. (antennae, head, forcipule, collum, trunk, trunk legs and last pair of legs) by using a simple chemical procedure. Also, it gives a biotechnological perspective to the organisms in the group of Chilipoda.

Three-dimensional chitin rings from body segments of a pet diplopod species: Characterization and protein interaction studies.

Physicochemical characterization of new chitin isolates can provide valuable insights into designing of biomimetic materials. Chitin isolates with a definite three-dimensional (3D) structure can exhibit characteristics that distinguish them from other chitin specimens that are in form of powder or flakes without a definite and uniform shape. Herein, 3D chitin rings were produced from body segments of a diplopod (Archispirostreptus gigas) inhabiting tropical regions. This organism is cultured easily and can reach 38cm in length, which makes it a suitable source for isolation of chitin. The chitin rings were characterized via TGA, FT-IR, SEM and XRD analyses. Enzymatic digestion test with chitinase demonstrated that chitin isolates had high purity (digestion rate: 97.4%). The source organism had high chitin content; 21.02±2.23% on dry weight. Interactions of the chitin rings with bovine serum albumin (BSA) protein were studied under different conditions (pH: 4.0-8.0, chitin amount: 6-14mg, contact time: 30-360min, protein concentration: 0.2-1mg/mL). The highest BSA adsorption was observed at pH5.0 at 20°C. The adsorption equilibrium data exhibited a better fit to Langmuir adsorption and the pseudo-first order kinetic models. The findings presented here can be useful for further studies aiming to develop biocompatible and nontoxic biomaterials.

Chitosan nanofiber production from Drosophila by electrospinning.

Drosophila melanogaster is one of the important test organisms in genetics thanks to its fast growth rate in a culture. This study demonstrates that the fly D. melanogaster can also be exploited as a source for nanofiber production in biotechnical applications. First, its chitin content was determined (7.85%) and then high molecular weight chitosan (141.4kDa) was synthesized through deacetylation of chitin isolates. Chitosan nanofibers with the diameter of 40.0073±12.347nm were produced by electrospinning of Drosophila chitosan. The physicochemical properties of obtained chitin and chitosan from D. melanogaster were determined by Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR). The study demonstrated that the fly D. melanogaster can be utilized for production of chitosan nanofiber concerning its cultivability and low-cost culture requirements.

GENDER INFLUENCES DIFFERENTIATION OF CHITIN AMONG BODY PARTS.

Earlier reports have established that chitin isolates from each body part of an insect cuticle can exhibit diverse physicochemical properties. But it is still unknown if the gender of the insect can influence characteristics of chitin isolates from different body parts. The present study addresses this question. As a result, important physicochemical differences in the chitin samples from different body parts of Melolontha sp. were recorded on the basis of sex. The chitin samples were extracted from eight different body parts (antennae, head, eyes, thorax, abdomen, elytra, hindwings, and legs) of female and male. The most remarkable variations in the chitin isolates from female and male body parts were recorded in chitin content, crystallinity, thermal stability, and surface morphology. And also it was wondered these chitin isolates from different body parts of female and male could find different applications. To check this hypothesis, the chitin samples from female and male were interacted with bovine serum albumin (BSA) protein and important variations were observed.

Effect of nonsteroidal anti-inflammatory drugs on colorectal distension-induced visceral pain.

OBJECTIVES: To investigate nonsteroidal anti-inflammatory drugs effectiveness in colorectal distension (CRD)-induced visceral pain model. MATERIALS AND METHODS: Male Sprague-Dawley (250-300 g) rats were anesthetized with ketamine (50 mg/kg, intraperitoneally [i.p.]) and chlorpromazine (25 mg/kg, i.p.). Two bipolar Teflon-coated Ni/Cr wire electrodes (80-M diameter) were placed in the abdominal external oblique muscle for the recording of electromyography. Jugular vein catheter was placed for the administration of drugs. CRD method was applied to evaluate of visceral pain. All drugs (paracetamol, meloxicam, metamizole, and dexketoprofen) administered intravenously. RESULTS: Paracetamol 200, 400, and 600 mg/kg did not change the visceromotor response (VMR) when compare with the control group. Meloxicam 2 and 4 mg/kg showed no effect but at doses of 6 mg/kg meloxicam significantly ([51.9 ± 6.4%] [P < 0.001]) decreased VMR compared with the control group. Metamizole 200 mg/kg did not change responses but dose of 400 and 600 mg/kg metamizole reduced VMR. Dexketoprofen 2 and 4 mg/kg did not cause a change in VMR but 6 mg/kg dose significantly reduced response compared with the control group ([43.9 ± 3.9%, 36.8 ± 2.8%, 34.8 ± 2.5%, 42.1 ± 4.8%, 40.7 ± 3.5%, 36.4 ± 2.7%, and 26.1 ± 2.2%]; from 10 min to 70 min, respectively, [P < 0.05]). CONCLUSION: Metamizole, dexketoprofen and meloxicam show antinociceptive effect with different duration of action on CRD-induced visceral pain model. This condition can be explained due to different chemical structures and different mechanisms which play a role in modulation of pain.

DNA interaction, antitumor and antimicrobial activities of three-dimensional chitosan ring produced from the body segments of a diplopod.

Commercially available chitins and the chitin isolated from mushrooms, insect cuticles, shells of shrimp, crab and crayfish reported in the literature are in forms of powder, flake or granule. Three-dimensional chitins have been only known from the sponges but still three-dimensional chitosan has not been reported yet. In this study, we produced three-dimensional chitin and chitosan rings from the body segments of a diplopod species (Julus terrestris). Obtained chitin and chitosan rings were characterized (by FT-IR, SEM, TGA, XRD, dilute solution viscometry and EA) and compared with commercial chitin and chitosan. The interactions with plasmid DNA was studied at varying concentrations of chitosan (0.04, 0.4 and 4mg/mL). Antitumor activity tests were conducted (L929 and HeLa), low cytotoxicity and high antiproliferative activity was observed. Antimicrobial activities of J. terrestris chitosan were investigated on twelve microorganisms and maximum inhibition (15.6±1.154mm) was recorded for common human pathogen Staphylococcus aureus.

Novel three-dimensional cellulose produced from trunk of Astragalus gummifer (Fabaceae) tested for protein adsorption performance.

This is the first study to produce three-dimensional (3D) cellulose from any plant up to now. This 3D cellulose was produced from Astragalus gummifer(Fabaceae) trunk by using a modified method in which original the shape of cellulose was kept as natural. This novel 3D cellulose was characterized by SEM, TGA, FT-IR, XRD and elemental analysis to evidence the purity and to compare it with commercially available cellulose from cotton. Results from these characterizations were found convincing because almost the same physicochemical properties were observed for both newly obtained 3D cellulose and commercial one. Both fibers and pores on the surface of 3D cellulose were observed. Thanks to its diversified surface morphology, this novel 3D cellulose was tested for its protein adsorption performance and the results were compared with commercial cellulose as follows: maximum adsorption capacity at pH 8.0 was recorded as 59.2 mg/g for 3D cellulose while 29.6 mg/g for commercial cellulose. According to this result, it is clear to say that this sorbent has high affinity for lysozyme. Also this 3D cellulose could be useful for the other areas of separation science.

Fluctuation in physicochemical properties of chitins extracted from different body parts of honeybee.

It is well known that physicochemical properties of chitin are related with the extraction method. Recently, it was revealed that some physicochemical properties of chitin are also related with taxonomical relationship. For the first time in this study, it was tested how these properties of chitin are affected by different body parts of one organism. The chitins were extracted from five different body parts (head, thorax, abdomen, legs and wings) of honeybee. These chitins were physicochemically characterized and differences among these body parts were identified. Highest chitin content was observed in legs (13.25%) while the lowest from thorax (6.79%). The surface morphologies of the isolated chitin structures from five different body parts were analyzed with SEM, as a result, five different types of surface morphologies were recorded. However, three different types of surface morphologies were observed only in abdomen. Maximum degradation temperatures (DTG(max)) of thorax, abdomen, legs and wings were recorded between 359 and 367 °C while DTG(max) value of head chitin was found as 308 °C.

First chitin extraction from Plumatella repens (Bryozoa) with comparison to chitins of insect and fungal origin.

Chitin immediately suggests the representatives of the kingdom Fungi, as well as such phyla as Annelida, Mollusca, Porifera, Cnidaria and, mostly, Arthropoda. Although Bryozoa also represents a chitin-containing phylum, no study has been developed yet on the isolation or characterization of the chitin from it. In this study, physiochemical properties of the chitin isolated from Plumatella repens belonging to the phylum Bryozoa was determined for the first time. The chitin structure was also studied comparatively by isolating chitin from an insect species (Palomena prasina) of the phylum Arthropoda, and Fomes fomentarius belonging to the kingdom Fungi. It was observed that the bryozoan chitin was in the α form, as in the arthropod and fungal chitins. The chitin contents in the dry weight of the bryozoan, fungal and insect species were observed to be 13.3%, 2.4%, and 10.8%, respectively. The insect chitin exhibited the highest thermal stability followed by that of the bryozoan and then the fungal chitins. Surface morphologies reveal that the insect and bryozoan chitins were composed of nano fibre and pore structures, whereas the fungal chitin had no pores or fibres. The crystallinity of the insect chitin (CrI=84.9%) was higher than the bryozoan (CrI=60.1%) and fungal chitins (CrI=58.5%).