Hydrogen peroxide bleaching of cellulose pulps obtained from brewer’s spent grain

Brewer’s spent grain (BSG) was evaluated for bleached pulp production. Two cellulose pulps with different chemical compositionswere produced by soda pulping: one from the original raw material and the other from material pretreated by dilute acid. Both of them were bleached by a totally chlorine-free sequence performed in three stages, using 5% hydrogen peroxide in the two initial, and a 0.25 NNaOHsolution in the last one. Chemical composition, kappa number, viscosity, brightness and yield of bleached and unbleached pulps were evaluated. The high hemicellulose (28.4% w/w) and extractives (5.8% w/w) contents in original BSG affected the pulping and bleaching processes.However, soda pulping of acid pretreated BSG gave a celluloserich pulp (90.4% w/w) with low hemicellulose and extractives contents (7.9% w/w and <3.4% w/w, respectively), which was easily bleached achieving a kappa number of 11.21, viscosity of 3.12 cp, brightness of 71.3%, cellulose content of 95.7% w/w, and residual lignin of 3.4% w/w. Alkaline and oxidative delignification of acid pretreated BSG was found as an attractive approach for producing high-purity, chlorine-free cellulose pulp.FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo), Brazil.CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico).Capes (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior)

Harmful and beneficial aspects of Parthenium hysterophorus: an update

Parthenium hysterophorus is a noxious weed in America, Asia, Africa and Australia. This weed is considered to be a cause of allergic respiratory problems, contact dermatitis, mutagenicity in human and livestock. Crop production is drastically reduced owing to its allelopathy. Also aggressive dominance of this weed threatens biodiversity. Eradication of P. hysterophorus by burning, chemical herbicides, eucalyptus oil and biological control by leaf-feeding beetle, stem-galling moth, stem-boring weevil and fungi have been carried out with variable degrees of success. Recently many innovative uses of this hitherto notorious plant have been discovered. Parthenium hysterophorus confers many health benefits, viz remedy for skin inflammation, rheumatic pain, diarrhoea, urinary tract infections, dysentery, malaria and neuralgia. Its prospect as nano-medicine is being carried out with some preliminary success so far. Removal of heavy metals and dye from the environment, eradication of aquatic weeds, use as substrate for commercial enzyme production, additives in cattle manure for biogas production, as biopesticide, as green manure and compost are to name a few of some other potentials. The active compounds responsible for hazardous properties have been summarized. The aim of this review article is to explore the problem P. hysterophorus poses as a weed, the effective control measures that can be implemented as well as to unravel the latent beneficial prospects of this weed

Progress and Research Needs of Plant Biomass Degradation by Basidiomycete Fungi

Peer reviewe

Curcumin Enhances Neurogenesis and Cognition in Aged Rats: Implications for Transcriptional Interactions Related to Growth and Synaptic Plasticity

Background: Curcumin has been demonstrated to have many neuroprotective properties, including improvement of cognition in humans and neurogenesis in animals, yet the mechanism of such effects remains unclear. Methodology: We assessed behavioural performance and hippocampal cell proliferation in aged rats after 6- and 12-week curcumin-fortified diets. Curcumin enhanced non-spatial and spatial memory, as well as dentate gyrate cell proliferation as compared to control diet rats. We also investigated underlying mechanistic pathways that might link curcumin treatment to increased cognition and neurogenesis via exon array analysis of cortical and hippocampal mRNA transcription. The results revealed a transcriptional network interaction of genes involved in neurotransmission, neuronal development, signal transduction, and metabolism in response to the curcumin treatment. Conclusions: The results suggest a neurogenesis- and cognition-enhancing potential of prolonged curcumin treatment i

Harnessing the potential of ligninolytic enzymes for lignocellulosic biomass pretreatment

Abundant lignocellulosic biomass from various industries provides a great potential feedstock for the production of value-added products such as biofuel, animal feed, and paper pulping. However, low yield of sugar obtained from lignocellulosic hydrolysate is usually due to the presence of lignin that acts as a protective barrier for cellulose and thus restricts the accessibility of the enzyme to work on the cellulosic component. This review focuses on the significance of biological pretreatment specifically using ligninolytic enzymes as an alternative method apart from the conventional physical and chemical pretreatment. Different modes of biological pretreatment are discussed in this paper which is based on (i) fungal pretreatment where fungi mycelia colonise and directly attack the substrate by releasing ligninolytic enzymes and (ii) enzymatic pretreatment using ligninolytic enzymes to counter the drawbacks of fungal pretreatment. This review also discusses the important factors of biological pretreatment using ligninolytic enzymes such as nature of the lignocellulosic biomass, pH, temperature, presence of mediator, oxygen, and surfactant during the biodelignification process

Short-Term Environmental Enrichment Enhances Adult Neurogenesis, Vascular Network and Dendritic Complexity in the Hippocampus of Type 1 Diabetic Mice

Background: Several brain disturbances have been described in association to type 1 diabetes in humans. In animal models, hippocampal pathological changes were reported together with cognitive deficits. The exposure to a variety of environmental stimuli during a certain period of time is able to prevent brain alterations and to improve learning and memory in conditions like stress, aging and neurodegenerative processes. Methodology/Principal Findings: We explored the modulation of hippocampal alterations in streptozotocin-induced type 1 diabetic mice by environmental enrichment. In diabetic mice housed in standard conditions we found a reduction of adult neurogenesis in the dentate gyrus, decreased dendritic complexity in CA1 neurons and a smaller vascular fractional area in the dentate gyrus, compared with control animals in the same housing condition. A short exposure-10 days- to an enriched environment was able to enhance proliferation, survival and dendritic arborization of newborn neurons, to recover dendritic tree length and spine density of pyramidal CA1 neurons and to increase the vascular network of the dentate gyrus in diabetic animals. Conclusions/Significance: The environmental complexity seems to constitute a strong stimulator competent to rescue th