Production of microbial lipids utilizing volatile fatty acids derived from wastepaper: A biorefinery approach for biodiesel production

Volatile fatty acids (VFAs) derived from organic wastes are being considered as low-cost feedstock for microbial lipid production as a valuable alternative to plant derived oils/biodiesel. In this study, VFAs were produced from anaerobic open culture fermentation of wastepaper and subsequently, used as a feedstock for lipid production by Cryptococcus curvatus. Total VFAs, yield and productivity achieved from waste office paper (WOP) and waste newspaper (WNP) were 17.3 and 10.2 g/L, 0.17 and 0.10 g/g TS, and 0.86 and 0.51 g/L/day, respectively. Biomass, lipid content and productivity achieved utilizing VFAs derived from WOP and WNP were 4.3 and 2.9 g/L, 41.2 and 27.7% DCW, and 0.037 and 0.033 g/L/h, respectively. The dominance of fatty acids such as oleic, palmitic, stearic and linoleic acid in the lipids suggests a high level of similarity with plant/vegetable oils used for biodiesel production. Therefore, VFAs derived from wastepaper could be potentially used as feedstock to produce microbial lipids towards cost-effective production of biodiesel

Synthesis of Pullulan-Mediated Silver Nanoparticles (AgNPs) and their Antimicrobial Activities

The synthesis of silver nanoparticles (AgNPs), using plant extracts, bacteria, fungi and yeasts, and their   antimicrobial activities have been widely investigated and well documented. However, pullulan AgNPs and their antimicrobial activities have not received much attention. The objective of this study was to synthesize pullulan AgNPs, characterize them, and test their antibacterial and antifungal activities. Pullulan was extracted from Aureobasidium mangrovei isolated from Oman and, using UV-Vis spectroscopy and Fourier Transform Infrared (FT-IR), found to be identical to the commercial pullulan obtained from Sigma, USA. Transmission electron microscopy (TEM) showed that most of the synthesized particles were poly-dispersed, irregular in shape, and most were spherical with an average size of 9.76 nm. Pullulan-mediated AgNPs were found to have antibacterial activities, and the ANOVA test showed that there were no significant differences between AgNO3, Pullulan and pullulan-mediated AgNPs for all the bacteria tested. Pullulan-mediated nanoparticles were found to have antifungal activity against Curvularia lunata, Fusarium incarnatum, Aspergillus niger, Aspergillus flavus, Aspergillus ochraceus and Penicillium sp. The ANOVA test also revealed that there was a significant difference in antifungal activity between pullulan and pullulan-mediated AgNPs, pullulan-mediated nanoparticles having shown a higher inhibitory activity than pullulan. Pullulan and pullulan-mediated nanoparticles could be used in the food industry and are safer than silver nitrates

Isolation and characterization of cellulolytic Bacillus licheniformis from compost

Eight cellulose degrading bacteria were isolated from compost and were identified as Bacillus licheniformis by 16S rRNA sequencing. Among the eight isolates, Bacillus licheniformis B4, B7 and B8 showed the highest cellulase activity. B. licheniformis B4 and B8 showed the maximum cellulase activity during the stationary phase of growth; but for B7, the maximum activity of cellulase was observed during the log phase. Reducing sugar released in the media, increased with increasing cellulase activity for all the three isolates. Significant correlation was observed between cellulase activity and protein content. The crude cellulase from B7 strain showed activity towards carboxymethyl cellulose and filter paper, but there was no detectable activity towards p-nitrophenyl- β-Dglucopyranoside (PNPG). The crude cellulase of B. licheniformis B7 exhibited maximum activity at 50°C and at pH 6 to 7.Keywords: Bacillus licheniformis, 16S rRNA, cellulase, reducing sugar, compost, viscosit

Changing Elemental Uptake of Roots and Leaves from Plants Grown on a Soil Variably Polluted by Crude Oil

International audienceA radish species was grown in a sandy loamy soil either unpolluted or polluted by increasing concentrations of crude oil added to watering solutions during one month under controlled laboratory conditions. This procedure was set to evaluate the impact of oil pollution of the substrate on the elemental uptake by plants. In summary, the increasing pollution by crude oil to the soil has not a univocal impact: the changing elemental contents in the roots and leaves of the cultivated radishes are never single trended with the amount of oil pollution, showing in turn that they are not provided by the spilled oil. The most significant elemental increase occurs in the leaves of the radishes grown in the soil polluted by 10 ml of oil and in the roots of those grown in the soil polluted by 4 ml of oil. In the detail, the significant effects of the oil pollution induce in the leaves: (1) similar behaviors for Ca, K, P, Mg, Fe and Al; (2) the highest impact on Ca, K, P, Mg and Al at the intermediate 10-ml pollution; (3) the highest uptake at the high side of pollution for Fe, Mn, Zn, Ni, Co, Cr and Pb; and (4) no significant impact on the uptake of the REEs. Oil pollution on the plant roots impacts: (1) an increased Ca, Fe, Al and Si uptake, often only in the case of the highest pollution, while P's uptake decreases; (2) an increase of the microbial population by a factor of about 2.5 at low pollution and a dramatic decrease at higher pollution; (3) an uptake of REEs only at the highest degree of pollution by a specific increase of the light REEs. The translocation roots-to-leaves indicates a decrease of Ca to the leaves when oil pollution increases, while remaining state for K and P with a slight decrease when pollution is at its maximum. The total biomass increases in the soil at low levels of pollution, decreases at intermediate levels and remains the same at high levels of pollution. The increase of most of elements at low level of oil supply is correlated with an increase in microorganism density, which suggests that availability of elements in soil can be attributed to an increase in organic activity, which has been stimulated by the oil pollution

Effects of Frankincense Compounds

Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection

Effects of Frankincense Compounds on Infection, Inflammation, and Oral Health

Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection. More recently, the bioactive components of Boswellia trees have been identified and characterized for their effects on cancer, microbial infection (especially infection by oral pathogens), and inflammation. Most studies have focused on cell lines, but more recent research has also investigated effects in animal models of disease. As natural products are considered to be safer than synthetic drugs, there is growing interest in further developing the use of substances such as frankincense oil for therapeutic treatment

Effects of Frankincense Compounds

Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection

Effects of Frankincense Compounds on Infection, Inflammation, and Oral Health.

Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection. More recently, the bioactive components of Boswellia trees have been identified and characterized for their effects on cancer, microbial infection (especially infection by oral pathogens), and inflammation. Most studies have focused on cell lines, but more recent research has also investigated effects in animal models of disease. As natural products are considered to be safer than synthetic drugs, there is growing interest in further developing the use of substances such as frankincense oil for therapeutic treatment