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Sawdust, a major waste product of the forestry industry, is accumulating along the Lagos Lagoon in Lagos, Nigeria, without it being effectively managed. Besides its use in manufacturing sound-absorbing boards to reinforce concrete beams and for energy purposes, its potential as a renewable energy source and feedstock for bio-product development has not yet been realized. Cellulose, a glucose biopolymer and structural component of cellulose can be hydrolyzed by a hydrolytic enzyme known as cellulase. During the process, the enzyme breaks the B-1,4-glucosidic bond, which keeps the glucose units together, and by acting on this bond, numerous glucose units are released. As part of sawdust, the cellulose molecule is not freely available for the degradation action of the cellulase enzyme as it is strongly associated with lignin, which acts as bio-glue, keeping cellulose and hemicellulose together. Delignification is an effective technique that was used to make the sawdust from ten different trees along the Lagos Lagoon in Nigeria more susceptible to saccharification by cellulase isolated from the fungus Aspergillus niger. Delignified and non-delignified sawdust masses between 2 mg and 10 mg were incubated with the A. niger cellulase solution (2 mg.mL-1), whereafter, the amount of sugar produced by the cellulase action was determined. The percentage saccharification of each sawdust material was also linked with the amount of sugar produced during cellulase action. From these investigations was concluded that delignification increased sugar production when almost all the masses of different sawdust materials were degraded. It was also observed that the ratio of sawdust mass to enzyme concentration is an important variable that influences the effectiveness of the saccharification process. The percentage saccharification of the various sawdust materials was also determined, and it indicated that the highest percentage of saccharification was not obtained when the highest amount of sawdust was degraded, producing the highest amount of sugar. The saccharification of sawdust could contribute to the development of renewable energy sources and feedstock for bioproduct development. The process is, however, not that straightforward as variables such as the type of cellulase enzyme, pretreatment of the cellulose substrate, and optimizing of cellulase to cellulose ratio are a few that need to be optimized for the process to be effective in terms of glucose production. [ABSTRACT FROM AUTHOR]

Sawdust, a product of the forest industry is mostly left untreated as solid waste. This phenomenon is well observed along the Lagos Lagoon in Nigeria where hundreds of trees are cut daily by sawmills to deliver wood for mainly the furniture industry. Different types of trees are utilized in this manner and the massive amounts of sawdust produced as a result of these activities are polluting the environment causing health risks for humans and animals. Cellulose, a glucose bio-polymer is a major structural component of sawdust and could be developed as a renewable energy resource should the cellulose be degraded into glucose, a fermentable sugar. This saccharification was done with Aspergillus niger cellulase and to make the cellulose more susceptible for cellulase action the sawdust was delignified with hydrogen peroxide. Both delignified and non-delignified sawdust were treated with the cellulase enzyme at incubation temperatures of 30°C, 40°C, 50°C, and 60°C. Delignification proved to be effective as an increased amount of sugar was released from all delignified sawdust materials relative to the non-delignified materials when saccharified with A. niger cellulase. Most of the materials were degraded at an incubation temperature of 40°C and 50°C and the highest percentage saccharification of 58% was obtained during the degradation of delignifed cellulose from the tree, Ricindendron heudelotti [ABSTRACT FROM AUTHOR]

Increased solid waste pollution and the negative effect of fossil fuel consumption on the environment are issues that would require more scientific attention and application to deal effectively with these phenomena. Wastepaper, a major component of solid waste, is classified as organic waste due to the presence of cellulose, a glucose-based biopolymer that is part of its structural composition. The saccharification of cellulose into glucose, a fermentable sugar, can be achieved with a hydrolytic enzyme known as cellulase. Although cellulase from fungal species such as Trichoderma, Aspergillus, and Penicillium are well described, knowledge about cellulase isolated from the brown garden snail is limited as it has not been the subject of many research endeavors. The waste paper has been described as a suitable resource for bio-energy development due to cellulose, a structural component of this bio-material that can be degraded into glucose, a fermentable sugar. Although paper materials such as newspaper, office paper, filter paper, Woolworths and Pick and Pay (retailers) advertising paper, as well as foolscap paper, were saccharified by different cellulases, the degradation of these paper materials by garden snail cellulase is a novel investigation from our laboratory. With the effects of temperature and incubation time on this cellulase action when degraded paper materials have already been investigated and reported, this study dealt with the garden snail cellulase action when degraded paper materials at different pH values. Most of the paper materials were degraded optimally at a pH value of 6.0, while optimum saccharification was observed at pH 4.5 when newspaper and brown envelope paper were degraded, with office paper showing maximum bioconversion at pH 7.0. The difference in the structural composition of the paper materials also affects the degree of saccharification, as the amount of sugar released from the various paper materials at optimum pH values is not similar. Together with other catalytic parameters, the pH value of this enzymatic catalysis is also to be considered when designing the development of waste paper as a bio-product resource, with limiting environmental pollution as an additional advantage of this process. [ABSTRACT FROM AUTHOR]

Environmental pollution and the exploitation of fossil-based products are topical issues that should be a matter of concern to the global population. The production of bio-based substances from waste biomass is a way to reduce the consumption of fossil fuels and limit environmental pollution. Enzymatic catalysed saccharification of cellulose is an important step for the bio-conversion of biomass such as waste paper into glucose that could be utilized as a feedstock for the production of value added bioproducts and this process can also be considered as an alternative route of waste management. During this study, fresh cellulase enzyme from Trichoderma viride was incubated separately with seven different waste paper materials during twelve successive incubation periods of 2 h each. The amount of sugar released from each paper material during each incubation period was determined. The highest sugar concentration released from each paper materials was produced during the first incubation period except the filter paper for which the highest amount of sugar was produced during the 9th period of incubation. During these optimum sugar producing incubation periods the highest total sugar concentration was released from brown envelope paper (3.3 mg.mL-1 followed by foolscap paper (3.0 mg.mL-1) and office paper (2.8 mg.mL-1) while the lowest amount of sugar was released from Pick ’n Pay paper (0.6 mg.mL-1). The relative saccharification percentage was also calculated which showed that filter paper produced the highest amounts of sugar followed by newspaper, and foolscap paper with advertising paper from a retailer. Pick ’n Pay offered the highest resistance towards cellulase catalysed bio-conversion into sugar. [ABSTRACT FROM AUTHOR]

Different used paper materials and mixtures thereof were saccharified with Penicillium funiculosum cellulase. Non-similar biodegradation patterns were concluded to be operating as well as declining bioconversion efficiencies with increasing biodegradation. Biowaste mixtures were less effectively biodegraded indicating the importance of separating biowaste into distinctive materials prior to developing it as a resource of bioproduct synthesis. [ABSTRACT FROM AUTHOR]

Investigates the bioconversion of the cellulose section of wastepaper materials to sugars by cellulase. Structural components of paper materials; Factors determining the efficiency of the bioconversion process; Details on the recycling of used paper materials.

Various used paper materials have been exposed to the action of cellulases from Penicillium funiculosum, Trichoderma reesei, Trichoderma viride and Aspergillus niger. A 2 h incubation period showed cellulase from T. viride the most active except for office paper that was maximally degraded by A. niger cellulase. Cellulase mixtures increased saccharification while sequential treatment with cellulases from T. reesei and P. funiculosum increased biodegradation at values between 15% and 190%. The maximum increase of saccharification (190%) was obtained when T. reesei cellulase initiated the sequential treatment of newspaper relative to the sole action of P. funiculosum cellulase on this non-pretreated and pretreated material. [ABSTRACT FROM AUTHOR]

Garden snails ( Cornu aspersum ) have been sacrificed by drowning the snails overnight in water. The visceral organs (inside the shell organs) have been separated from the foot as well as the shell and homogenized using tris-HCl buffer, pH 5. The homogenate of visceral organs was dialysed in distilled water at 4 °C for 18 h where after the dialysed material was used to bio-convert the cellulose component of various waste paper materials into fermentable sugars such as glucose. Saccharification of the waste cellulose materials was performed with the extracted snail cellulase during ten consecutive incubation periods of 2 h each. The amount of sugars produced during cellulase action on waste cellulose was determined by the dinitrosalicylic acid (DNS) method. All incubations were performed in triplicate and the percent saccharification of each paper material was determined as a fraction of the paper material exposed to cellulase action. •Cellulase extracted from brown garden snail•Saccharification of waste paper using garden snail cellulase.

Ethnopharmacological Relevance: [corrected] Traditional herbal medicines are often used for the treatment of different diseases in developing countries, especially in the rural areas where a lack of an efficient primary health care system is usually experienced. Many patients infected with the human immunodeficiency virus are taking traditional herbal medicines in conjunction with their modern antiretroviral medication and drug-herb interactions can occur in these cases., Aim of the Study: To investigate the effect of water extracts of two traditional medicinal plants, Hypoxis hemerocallidea and Sutherlandia frutescens as well as l-canavanine (a constituent of Sutherlandia frutescens) on the transport of nevirapine across human intestinal epithelial cells., Materials and Methods: Nevirapine transport in the apical to basolateral and basolateral to apical directions across Caco-2 cell monolayers was determined alone (normal control) and in the presence of verapamil (positive control), water extracts of Hypoxis hemerocallidea and Sutherlandia frutescens and an aqueous solution of l-canavanine. The cumulative transport and apparent permeability coefficient (P(app)) values were calculated and compared., Results: Nevirapine alone was substantially effluxed in the basolateral to apical direction across the intestinal epithelial cell monolayers, which was statistically significantly (p < or = 0.05) decreased by addition of verapamil, Hypoxis hemerocallidea extract and the l-canavinine solution. The effect of Sutherlandia frutescens on nevirapine transport was not statistically significantly different from the control., Conclusions: Hypoxis hemerocallidea and l-canavanine interact with the efflux of nevirapine across intestinal epithelial cells and therefore can potentially increase the bioavailability of this antiretroviral drug when taken concomitantly.

Environmental issues such as the depletion of non-renewable energy resources and pollution are topical. The extent of solid waste production is of global concern and development of its bioenergy potential can combine issues such as pollution control and bioproduct development, simultaneously. Various wastepaper materials, a major component of solid waste, were treated with the cellulase enzyme from Trichoderma viride, thus bioconverting their cellulose component into fermentable sugars. All wastepaper materials exhibited different susceptibilities towards the cellulase as well as the production of non-similar sugar releasing patterns when increasing amounts of paper were treated with a fixed enzyme concentration. The hydrolysis of wastepaper with changing enzyme concentrations and incubation periods also resulted in dissimilar sugar-producing tendencies. A general decline in hydrolytic efficiency was observed when increasing sugar concentrations were produced during biodegradation of all wastepaper materials.