Cellulose Degradation Enzymes in Filamentous Fungi, A Bioprocessing Approach Towards Biorefinery

The economic exploration of renewable energy resources has hot fundamentals among the countries besides dwindling energy resources and increasing public pressure. Cellulose accumulation is a major bio-natural resource from agricultural waste. Cellulases are the most potential enzymes that systematically degrade cellulosic biomass into monomers which could be further processed into several efficient value-added products via chemical and biological reactions including useful biomaterial for human benefits. This could lower the environmental risks problems followed by an energy crisis. Cellulases are mainly synthesized by special fungal genotypes. The strain Trichoderma orientalis could highly express cellulases and was regarded as an ideal strain for further research, as the genetic tools have found compatibility for cellulose breakdown by producing effective cellulose-degrading enzymes. This strain has found a cellulase production of about 35 g/L that needs further studies for advancement. The enzyme activity of strain Trichoderma orientalis needed to be further improved from a molecular level which is one of the important methods. Considering synthetic biological approaches to unveil the genetic tools will boost the knowledge about commercial cellulases bioproduction. Several genetic transformation methods were significantly cited in this study. The transformation approaches that are currently researchers are exploring is transcription regulatory factors that are deeply explained in this study, that are considered essential regulators of gene expression.

Prospecting cellulose fibre-reinforced composite membranes for sustainable remediation and mitigation of emerging contaminants

Many environmental pollutants caused by uncontrolled urbanization and rapid industrial growth have provoked serious concerns worldwide. These pollutants, including toxic metals, dyes, pharmaceuticals, pesticides, volatile organic compounds, and petroleum hydrocarbons, unenviably compromise the water quality and manifest a severe menace to aquatic entities and human beings. Therefore, it is of utmost importance to acquaint bio-nanocomposites with the capability to remove and decontaminate this extensive range of emerging pollutants. Recently, considerable emphasis has been devoted to developing low-cost novel materials obtained from natural resources accompanied by minimal toxicity to the environment. One such component is cellulose, naturally the most abundant organic polymer found in nature. Given bio-renewable sources, natural abundance, and impressive nanofibril arrangement, cellulose-reinforced composites are widely engineered and utilized for multiple applications, such as wastewater decontamination, energy storage devices, drug delivery systems, paper and pulp industries, construction industries, and adhesives, etc. Environmental remediation prospective is among the fascinating application of these cellulose-reinforced composites. This review discusses the structural attributes of cellulose, types of cellulose fibrils-based nano-biocomposites, preparatory techniques, and the potential of cellulose-based composites to remediate a diverse array of organic and inorganic pollutants in wastewater.

Ab initio study for superior sensitivity of graphyne nanoflake towards nitrogen halides over ammonia

Graphyne (GYN) has received immense attention in gas adsorption applications due to its large surface area. The adsorption of toxic ammonia and nitrogen halides gaseous molecules on graphyne has been theoretically studied at ωB97XD/6-31 + G(d, p) level of DFT. The counterpoise corrected interaction energies of NH₃, NF₃, NCl₃, and NBr₃ molecules with GYN are - 4.73, - 2.27, - 5.22, and - 7.19 kcal mol^-1, respectively. Symmetry-adapted perturbation theory (SAPT0) and noncovalent interaction index (NCI) reveal that the noncovalent interaction between analytes and GYN is dominated by dispersion forces. The significant change in electronic behavior, i.e., energies of HOMO and LUMO orbitals and NBO charge transfer correspond to the pronounced sensitivity of GYN towards considered analytes, especially NBr₃. Finally, TD-DFT calculation reveals a decrease in electronic transition energies and shifting of adsorption to a longer wavelength. The recovery time for NX₃@GYN is observed in nanoseconds, which is many orders of magnitude smaller than the reported systems. The recovery time is further decreased with increasing temperature, indicating that the GYN benefits from a short recovery time as a chemical sensor.

Electrochemical sensing behavior of graphdiyne nanoflake towards uric acid: a quantum chemical approach

Though the gas sensing applications of graphdiyne have widely reported; however, the biosensing utility of graphdiyne needs to be explored. This study deals with the sensitivity of graphdiyne nanoflake (GDY) towards the uric acid (UA) within the density functional framework. The uric acid is allowed to interact with graphdiyne nanoflake from all the possible orientations. Based on these interacting geometries, the complexes are differentiated with naming, i.e., UA1@GDY, UA2@GDY, UA3@GDY, and UA4@GDY (Fig. 1). The essence of interface interactions of UA on GDY is derived by computing geometric, energetic, electronic, and optical properties. The adsorbing affinity of complexes is evaluated at ωB97XD/6-31 + G(d, p) level of theory. The stabilities of the complexes are quantified through the interaction energies (E_int) with reasonable accuracy. The calculated E_int of the UA1@GDY, UA2@GDY, UA3@GDY, and UA4@GDY complexes are - 31.13, - 25.87, - 20.59, and - 16.54 kcal/mol, respectively. In comparison with geometries, it is revealed that the higher stability of complexes is facilitated by π-π stacking. Other energetic analyses including symmetry adopted perturbation theory (SAPT), noncovalent interaction index (NCI), and quantum theory of atoms in molecule (QTAIM) provide the evidence of dominating dispersion energy in stabilizing the resultant complexes. The HOMO-LUMO energies, NBO charge transfer, and UV-vis analysis justify the higher electronic transition in UA1@GDY, plays a role of higher sensitivity of GDY towards the π-stacked geometries over all other possible interaction orientations. The present findings bestow the higher sensitivity of GDY towards uric acid via π-stacking interactions. Fig. 1 Optimized geometries (with interaction distances in Å) of UA@GDY complexes.

First Report of Groundnut bud necrosis virus in Tomato in Bangladesh

An unusual disease of tomato characterized by leaf mottling and necrotic streaks on veins, shortened internodes, necrosis of terminal buds, and concentric rings on fruits was observed during 2010 to 2011 surveys in tomato growing regions of Godagari Upzila, Rajshahi district, Bangladesh. Disease incidence in popularly grown F1 hybrid cultivars, which include Sobal, Abhiruchi, Salamat, Bangobir, and BARI hybrid tomato-5 and -6 in about 40 commercial fields, ranged from 40 to 90%. Extracts from the field samples (n = 10) reacted with polyclonal antiserum to Groundnut bud necrosis virus (GBNV) in direct antigen coated ELISA, suggesting the association of a tospovirus antigenically related to serogroup IV topsovirus (1). To identify whether the tospovirus was a distinct virus species, ELISA-positive samples were subjected to total RNA extraction with an RNeasy Plant Mini Kit (Qiagen, Chatsworth, CA) followed by reverse transcription (RT)-PCR with tospovirus-specific primers (5'-ATGGTTGAAAAGAGCAAGAATGATGC-3') and degenerate primer (5'-CTTCTTATGAAGTGTACTCACCATAAGTCATCC-3') derived from the conserved sequences of GBNV, Watermelon bud necrosis virus (WBNV), and Capsicum chlorosis virus (CaCV) (2). The RT-PCR product was cloned into pGEM-T Easy vector (Promega, Madison, WI) and sequenced at Department of Biochemistry, University of Delhi, South Campus, Delhi, India (GenBank Accession No. JQ692083). The sequences of cloned fragments were assembled. Analysis of the 477-bp region of the nucleocapsid protein (N) gene revealed that the tomato tospovirus shared maximum identity both at the nucleotide (96%) and amino acid (97%) levels with the corresponding region of GBNV. In contrast, only 78 to 81% and 85 to 87% identity at nucleotide and amino acid levels, respectively, was observed with the corresponding region of the N genes of CaCV, WBNV, and Watermelon silver mottle virus. These results suggested the association of GBNV with the diseased tomato samples. To our knowledge, this is the first report of GBNV infecting tomato in Bangladesh and regular surveys are necessary to ascertain the prevalence and incidence of GBNV in other crops. References: (1) R. K. Jain et al. J. Virol. Methods 130:162, 2005. (2) M. Tsompana and J. W. Moyer. Tospovirus. Page 157 in: Encyclopedia of Virology. Academic Press, New York, 2009.

Epilepsy in children with cerebral palsy

This was a prospective analytical study done from October'99 through December 2000 to observe the clinical profile of epilepsy in children with cerebral palsy. Sixty epileptic children with cerebral palsy were studied and their results were compared with the results of epilepsy in 30 developmentally normal children. Ages of all children studied were 1-15 years. Majority were below five years of age and male out numbered female. Spastic quadriplegia (60%) was the commonest type of cerebral palsy. Generalized tonic-clonic seizure (66%) was the commonest seizure type in both groups. Second most common type of seizure was partial (13%) and myoclonic (29%) in developmentally normal and cerebral palsy children respectively. Mental retardation (63%) and speech delay (58%) were the two common associated problems in cerebral palsy patients. Ventriculomegaly (55%) was the commonest computed tomographic findings in cerebral palsy patients. In electro encephalography generalized epileptiform activity was the commonest finding in both groups. Clinical pattern is different in many ways when epilepsy is associated with cerebral palsy.

Effect of cimetidine, ranitidine and tiotidine on plasma testosterone and luteinizing hormone levels in rats

This investigation was carried out to study the comparative effects of cimetidine, ranitidine and tiotidine on the plasma levels of testosterone and luetinizing hormone under local conditions. The three H(2)-blocking drugs were injected to the adult male albino rats twice daily at the recommended therapeutic dose levels for six weeks. The data obtained showed that only tiotidine caused a significant (<0.05) increase in the level of testosterone. However, all the three drugs caused a significant rise in the levels of luteinizing hormone with the most active ranitidine administration.

Fetal exsanguination associated with antepartum hemorrhage

Fetal bleeding in utero is infrequent. It is usually life-threatening but can be treated successfully in most cases if recognized early. Four cases are described and it is suggested that screening for fetal blood be done in all instances of antepartum hemorrhage.

Respiratory distress syndrome and the value of amniotic fluid phospholipids in predicting such complications before birth

The amniotic fluid study of 80 samples from 40 patients, obtained by amniocentesis between 28 and 40 weeks of pregnancy, was carried out. It was noted that L/S (Lecithin/Sphingomyelin) ratio was significantly different at 36-38 weeks of pregnancy when compared with values in pregnancies of less than 36 weeks gestation (P less than 0001). No cases of RDS occurred when the L/S ratio was mature 4 or more. A brief review of recent developments in etiology of RDS are also presented.

The use of ultrasound in obstetrics and gynecology

Advantages of ultrasound as a diagnostic tool are many. The patient experiences no discomfort, nor does she feel any sensation. The patient can be examined without moving from her bed. Unlike x-ray, there is no danger of exposing the fetus and the mother to adverse effects of radiation. Its application in determination of fetal death, early in pregnancy, diagnosis of hydatidiform mole and localization of the placenta in cases of antepartum hemorrhage are only some of the obvious applications of this method.