Physico-chemical and structural characterization of mucilage isolated from seeds of Diospyros melonoxylon Roxb.

Mucilagem foi isolada de sementes de Diospyros melanoxylon Roxb, uma planta que cresce naturalmente nas florestas da Índia. Vários métodos físico-químicos, como análise de partículas, microscopia electrônica, calorimetria diferencial de varredura, análise térmica diferencial, análise termogravimétrica, massa molecular por cromatografia de permeação em gel, viscosidade, análise elementar, espectrometria de difração de raios-x, potencial zeta, espectroscopia no infravermelho com transformada de Fourier, 1D (1H e 13C) (NMR) foram utilizados no presente estudo para caracterizar essa goma. A análise de partículas sugere que a mucilagem tem tamanho de partícula em nm. A análise SEM sugere que a mucilagem tem tamanho de partícula irregular. Observou-se temperatura de transição vítrea da goma de 78 °C e 74 °C por DSC e DTA, respectivamente. A análise termogravimétrica sugeriu que a mucilagem possuía boa estabilidade térmica, com duas fases de decomposição. A massa molecular da mucilagem foi 8760, por meio de cromatografia de permeação em gel, enquanto que a viscosidade foi 219,1 cP. O padrão de DRX da mucilagem indicou natureza completamente amorfa. Os principais grupos funcionais identificados a partir do espectro de FT-IR foram: 3441 cm-1 (-OH), 1632 cm-1 (-COO-), 1414 cm-1 (-COO-) e 1.219 cm-1 (CH3CO-). As análises de mucilagem por cromatografia em papel e 1D RMN indicaram a presença de açúcares.Mucilage was isolated from the seeds of Diospyros melonoxylon Roxb., a plant growing naturally in the forests of India. Various physico-chemical methods like particle analysis, scanning electron microscopy, differential scanning calorimetry, differential thermal analysis, thermogravimetry analysis, molecular weight by gel permeation chromatography, rheometry, elemental analysis, x-ray diffraction spectrometry, zeta potential, fourier transform infrared spectroscopy, 1D(1H and 13C) (NMR) have been employed to characterize this gum in the present study. Particle analyses suggest that mucilage had particle size in nanometer. SEM analysis suggested that the mucilage had irregular particle size. The glass transition temperature of the gum observed was 78 °C and 74 °C by DSC and DTA respectively. The Thermogravimetry analysis suggested that mucilage had good thermal stability with two stage decomposition. The molecular weight of mucilage was determined to be 8760, by gel permeation chromatography, while the viscosity of mucilage was observed to be 219.1 cP. The XRD pattern of the mucilage indicated a complete amorphous nature. Elemental analysis of the gum revealed specific contents of carbon, hydrogen, nitrogen and sulfur. The major functional groups identified from FT-IR spectrum include 3441 cm-1 (-OH), 1632 cm-1 (-COO-), 1414 cm-1 (-COO-) and 1219 cm-1 (-CH3CO). Analysis of mucilage by paper chromatography and 1D NMR indicated the presence of sugars

In vivo mucoadhesive strength appraisal of gum Manilkara zapota

Mucilagem (MMZ) extraída das sementes de Manilkara zapota(Linn.) P. Royen syn utilizando técnicas de maceração foi avaliada por sua força mucoadesiva por vários métodos in vitro e in vivo. O resultado mostrou que a força mucoadesiva das sementes mucilaginosas tem propriedade comparável aos polímeros naturais e sintéticos, tais como goma Guar e hidroxipropilmetil celulose (HPMC E5LV) nas condições experimentais utilizadas neste estudo. Brevemente, se pode concluir que a mucilagem de semente de Manilkara zapota pode ser usada como um excipiente farmacêutico em sistemas de liberação de fármacos mucoadesivos por via oral. Pode ser apropriado o estudo posterior de mudanças nessas propriedades após modificações químicas.The mucilage (MMZ) extracted from the seeds of Manilkara zapota(Linn.) P. Royen syn. using maceration techniques was evaluated for mucoadhesive strength by various in vitro and in vivo methods. The result showed that mucoadhesive strength of seeds mucilage have comparable property toward natural and synthetic polymers such as Guar Gum and hydroxyl propyl methyl cellulose (HPMC E5LV) under the experimental conditions used in this study. Briefly, it could be concluded that the seed mucilage of Manilkara zapota can be used as a pharmaceutical excipient in oral mucoadhesive drug delivery systems. Further, it may be appropriate to study the changes in these properties after chemical modifications

An Experimental Investigation of Fatigue Performance for A Flexure Spring

In order to prevent a free-piston Stirling cryocooler failure during mission life, the flexure spring's fatigue life is most critical and important. In the current research, an effort is made to examine fatigue life. The fatigue life testing of cryocooler flexures is frequently discussed in the literature. However, more information is needed about the economic approach and hardware needed for the testing. This research paper adopts the FEA approach of flexure spring and outlines the criteria for flexure fatigue testing. A moving coil linear motor was also designed and selected for the oscillating shaft and bending special-purpose flexure spring stack to validate stiffness criteria. The 108 no. of cycles required to validate the fatigue limit were also attained using the approach in a few days when testing at a relatively high frequency

An Experimental Investigation of Fatigue Performance for A Flexure Spring

In order to prevent a free-piston Stirling cryocooler failure during mission life, the flexure spring's fatigue life is most critical and important. In the current research, an effort is made to examine fatigue life. The fatigue life testing of cryocooler flexures is frequently discussed in the literature. However, more information is needed about the economic approach and hardware needed for the testing. This research paper adopts the FEA approach of flexure spring and outlines the criteria for flexure fatigue testing. A moving coil linear motor was also designed and selected for the oscillating shaft and bending special-purpose flexure spring stack to validate stiffness criteria. The 108 no. of cycles required to validate the fatigue limit were also attained using the approach in a few days when testing at a relatively high frequency

LESS-WEIGHT AIRCRAFT WING DESIGN FRAMEWORK USING REINFORCED MATERIAL

The primary number of materials in aircraft construction continues to be wood, steel, aluminum alloys and much more lately, titanium alloys and fiber reinforced composites. Several factors influence selecting material which strength allied to lightness is an essential. Subsonic aircraft can be used as business jets and commercial airplanes. The wings are often straight or with low sweep position. Composite materials are very well recognized for their excellent mixture of high structural stiffness and occasional weight.CFC is viewed to possess a modulus two times &strength three occasions those of aluminum alloy, the traditional materials in aircraft construction. In the studies conducted concerning the fat loss, it's believed that substitute of Al. alloy by CFC leads to 52.96% saving within the total structural weight from the aircraft wing. In our work the aircraft wing components skin is examined thinking about both isotropic and composite materials. The parametric study conducted using MSc Nastran finite element package

Studies on Haloalkaliphilic Bacteria Isolated from Lonar Meteorite Crater in India

Haloalkaliphilic bacteria were isolated from water samples collected from alkaline Lonar meteorite crater, (MS) India having pH 10.5. Among them one of the bacterial strains was identified by 16S rRNA sequencing showed 97% alignment match with Bacillus fusiformis. The optimum growth of such organism was at 12.5 pH and 18% salt concentration. Chemical analysis of water showed higher amount of metal ions and salts concentrations present in lonar crater. The Bacillus fusiformis have potential to produce hydrolytic enzyme such as amylases. The amylase was partially purified by 80% ammonium sulphate and obtained 2 fold increase amylase activity. The optimum enzyme activity was at 10 pH and 30°C temperature of. The enzyme was incubated in presence of different metal ions and showed its stability at 1mM concentration of MgSO4

Life History Traits of Talicada nyseus (Lepidoptera: Lycaenidae) Butterfly Under Laboratory Conditions

The butterfly Talicada nyseus G. (Lepidoptera: Lycaenidae) is abundant in India and Sri Lanka (Karunaratne, et al., 2002). In India, this butterfly is chiefly found in the peninsular area, Maharashtra, Karnataka, Punjab and foothills of the Himalayas (Singh, 2005). The host plants of this butterfly include Kalanchoe spp. (Saxifragales: Crassulaceae). Adult Talicada nyseus feed on nectar of surrounding flowering plants but are also reported to feed on lichens (Karunaratne, et al., 2002). Recently it has been discovered that Talicada nyseus is infected with maternally inherited Wolbachia bacteria (Ankola, et al., 2011; Salunke, et al., 2012) and exhibits a female biased sex ratio (Ankola, et al., 2011). It is suspected that the presence of the female biased sex ratio in this butterfly is caused by its endosybiont Wolbachia. As an endosymbiont, Wolbachia is known to cause female biased sex ratio in butterfly hosts by inducing two distinct reproductive anomalies: feminization of genetic males (Hiroki et al., 2004) and male killing (Jigginset al., 2001; Charlat et al., 2005). It is essential to record scientific data regarding the life history traits of Talicada nyseus naturally infected with Wolbachia. In the present report life history traits of Talicada nyseus which harbor Wolbachia infection were studied under controlled conditions. The individual Talicada nyseus specimens used for the study were collected from a laboratory reared population which was previously confirmed to be heavily infected with Wolbachia. Five individual mated pairs were used separately for the present study. The life cycle was analyzed at 28.09 ± 0.564° C. The data collected were statistically analyzed by paired t-test with the help of SPSS 7.5. Wolbachia infection in this butterfly was previously documented by Ankola etal. (2011). The fecundity of Talicada nyseus was found to be ranging from 61.6± 12.08 to 66.4 ± 17.75 (Table 1). The fecundity data obtained from the present study is in agreement with our previous report (Ankola et al., 2011). More than 95% hatchability was recorded during the present investigation indicating that there might not be male-killing induced by Wolbachia in Talicada nyseus (Jiggins et al., 2000; Charlat et al., 2007). The hatching time required for eggs ranged from 7.4 ± 1.83 to 9.6 ± 2.71 (Table 1). Furthermore, the time required for th

Kinase-independent role for CRAF-driving tumour radioresistance via CHK2

Although oncology therapy regimens commonly include radiation and genotoxic drugs, tumour cells typically develop resistance to these interventions. Here we report that treatment of tumours with ionizing radiation or genotoxic drugs drives p21-activated kinase 1 (PAK1)-mediated phosphorylation of CRAF on Serine 338 (pS338) triggering a kinase-independent mechanism of DNA repair and therapeutic resistance. CRAF pS338 recruits CHK2, a cell cycle checkpoint kinase involved in DNA repair, and promotes CHK2 phosphorylation/activation to enhance the tumour cell DNA damage response. Accordingly, a phospho-mimetic mutant of CRAF (S338D) is sufficient to induce the CRAF/CHK2 association enhancing tumour radioresistance, while an allosteric CRAF inhibitor sensitizes tumour cells to ionizing radiation or genotoxic drugs. Our findings establish a role for CRAF in the DNA damage response that is independent from its canonical function as a kinase

Teleological role of L-2-hydroxyglutarate dehydrogenase in the kidney

L-2-hydroxyglutarate (L-2HG) is an oncometabolite found elevated in renal tumors. However, this molecule might have physiological roles that extend beyond its association with cancer, as L-2HG levels are elevated in response to hypoxia and during Drosophila larval development. L-2HG is known to be metabolized by L-2HG dehydrogenase (L2HGDH), and loss of L2HGDH leads to elevated L-2HG levels. Despite L2HGDH being highly expressed in the kidney, its role in renal metabolism has not been explored. Here, we report our findings utilizing a novel CRISPR/Cas9 murine knockout model, with a specific focus on the role of L2HGDH in the kidney. Histologically, L2hgdh knockout kidneys have no demonstrable histologic abnormalities. However, GC-MS metabolomics demonstrates significantly reduced levels of the TCA cycle intermediate succinate in multiple tissues. Isotope labeling studies with [U-13C] glucose demonstrate that restoration of L2HGDH in renal cancer cells (which lowers L-2HG) leads to enhanced incorporation of label into TCA cycle intermediates. Subsequent biochemical studies demonstrate that L-2HG can inhibit the TCA cycle enzyme α-ketoglutarate dehydrogenase. Bioinformatic analysis of mRNA expression data from renal tumors demonstrates that L2HGDH is co-expressed with genes encoding TCA cycle enzymes as well as the gene encoding the transcription factor PGC-1α, which is known to regulate mitochondrial metabolism. Restoration of PGC-1α in renal tumor cells results in increased L2HGDH expression with a concomitant reduction in L-2HG levels. Collectively, our analyses provide new insight into the physiological role of L2HGDH as well as mechanisms that promote L-2HG accumulation in disease states