Fungal biotreatment of agro-industrial wastes for the production of bioethanol in bioreactor

BIOETHANOL production from lignocellulosic feedstocks is considered a promising strategy to increase global production of biofuels without impacting food supplies. This work aimed to evaluate bioethanol production by baker's yeast using a medium containing the hydrolysate of fungal biotreatment of five different lignocellulosic feedstocks with some amendments. The pretreatment of lignocellulosic feedstocks using 5 % w/v NaOH, 1 % v/v H[2]SO[4] and sodium hypochlorite: H[2]O[2][10:1] prior to fungal biotreatment was studied. For bioethanol production, batch, fed-batch [two strategies] and continuous cultivations of baker's yeast on the fungal biotreated rice straw hydrolysate was evaluated in bioreactor. In batch and pulsed fed-batch cultivations, the highest bioethanol concentration, conversion coefficient, bioethanol yield and productivity were [0.41 % v/v, 36.9 % v/w, 36,9 % v/w and 0.114 ml/l/h, respectively], while in fed-batch cultivation with continuous feeding these parameters were [0.45 % v/v, 40 % v/w,. 40.5 v/w % and 0,015 ml/l/h, respectively]. The highest bioethanol concentration [0.52 % v/v] was obtained in continuous culture at dilution rate of 0.03 h[-1]. while conversion coefficient; yield and productivity were 31.2 % v/w, 31.4 % v/w and 0.022 ml/l/h, respectively

Evaluation of lipid-producing yeast for biodiesel production

FUNGAL xylanase and lignin peroxidase enzymes were used as pretreatment for biobleaching of bagasse biopulping treated with mixed culture of Ophiostoma piliferum and Ceriporiopsis subvermispora SS- 33 at 27°C for one week in MV medium as static culture before the pulping with propylene glycol [PG]. Some agricultural wastes such as corn cobs, wheat bran and bagasse powder were used as a sole carbon source for xylanase production. The maximum production of fungal xylanase was attained after 7 days- fermentation period on corn cobs medium at 30°C on rotary shake flasks at 150 rpm. The enzyme production by Trichoderma reesie NRRL 6156 increased 1.17 fold as compared with that obtained by Trichoderma viride NRRL 13034.Using 10.30 IU xylanase/g bagasse biopulp, produced by Trtchoderma reesie NRRL 6156, for 4 h at 50°C was the best xylanase pretreatment which reduced klason lignin% and increased the brightness % of bagasse biopulp. The solid-state HC-LN medium supplemented with tween 60 and veratryl alcohol in addition to 10 grams of bagasse pulp was the best one for lignin peroxidase production by Phanerochaete chrvsosporium NRRL 6361, the enzyme activity of this treatment [77.75 IU/L] was higher than that obtained using semi-solid [47.75 IU/L] and liquid [36.50 IU/L] state, after 6 days incubation period. The optimum lignin peroxidase dose, for the best biobleaching of unbleached bagasse biopulp at 37°C for 8 h was 1.54 lU/g. Using these enzyme pretreatments led to increase the brightness %, breaking length and tear factor 6.7, 18.89 and 12.7 % by xylanase bleached bagasse [XBB] and 8.94 %, 34.92 and 30.82 %, by lignin peroxidase bleached bagasse [LBB], respectively. The enzyme treatment of LBB and XBB led to decrease of chlorine consumption 40% and 26.67 % as compared to control. Scanning electron microscope [SEM] of bleached bagasse pulp clearly showed fiber that exposed to enzymes treatment had a more open surface and it becomes more accessible to subsequent bleaching agents. The biologicaly pretreatment of bagasse pulp with xylanase orlignin peroxidase enzymes led to increase in the crystallinty by 11.29 and 8.3 %, respectively

Optimization of biosurfactant production by bacillus licheniformis isolated from oil contaminated Egyptian soil

Optimal conditions for obtaining elevated biosurfactant production by a local strain of Bacillus licheniformis strain No. 5 were investigated. Modified minimal salt medium, pH 7.0, containing crude oil [1%], urea [2 g/l], KH[2]PO[4] + K[2]HPO[4] [2+2 g/l], MgSO[4] [0.2 g/l], yeast extract [1 g/l], and trace elements solution [0.1%] was found to be the most suitable for growth and emulsifying activity by this bacterium. High biosurfactant production was obtained after incubation for 7 days at 30° C. By providing the previous conditions, the emulsion index [E[24]%] was increased 3-fold as compared to that obtained via growth in the original minimal salt medium. In biorcactor batch culture, an agitation speed of 300 rpm attained the highest microbial growth [1.9 g cell dry weight/l] and an E[24]= 50.90% after 7 clays of incubation. In fed-batch culture, the pulsed addition of crude oil during the first 2 - 3 days of incubation enhanced the emulsification activity by 1.3-fold. The greatest E[24] was obtained using black grain oil [89.09%], followed by that obtained against diesel oil [87.27%]. The highest stability of emulsion index was recorded on diesel oil, which remained stable for 10 days [E[240]= 81.81%]. The biosurfactant showed an almost stable surface activity profile over a wide range of pH values [from 6 to 12]. The maximum emulsification activity was obtained at pH 8. The reduction in E[24] after exposure of the biosurfactant to 121°C for 15 min against diesel oil and toluene was 43.7% and 28.6%, respectively. Chemical analyses of the purified biosurfactant showed that it is a lipoprotein. Significant emulsification activity was detected towards different aliphatic and aromatic hydrocarbons and vegetable oils. The purified biosurfactant contained 41.7% C, 7.4% H and 5.8% N and was comprised of 36.2% proteins, 12.3% lipids and 5.6% carbohydrates

Formulation of site-specific mucoadhesive liquid suppositories as a method to decrease hepatotoxicity in rabbits

Mucoadhesive liquid suppositories containing diclofenac sodium [DS] as a NSAID were prepared using poloxamers as a liquid suppository base. Various formulations composed of different ratios of P407 and P188 [10/20, 15/15, 21/9, 24/6 and 27/3% w/w of P 407/P188] were prepared. The physicochemical characters; the gelation temperature, gel strength and mucoadhesive properties of the prepared suppositories were evaluated and compared with conventional suppositories. The dissolution and pharmacokinetic parameters of DS from such suppositories were also estimated. It was also important to study the histopathological changes in rabbit rectum and liver after administration of liquid and conventional suppositories. The gelation temperatures were 49.5, 45.5, 32.5, 22.5 and 20.5 C for 10/20, 15/15, 21/9, 24/6 and 27/3% w/w of P407/P188, respectively. P407/P188 mixture in the concentration of 21/9%, w/w was selected as the system of choice since it exhibited adequate physicochemical properties. The addition of DS increased the gelation temperature [from 18 to 32.5 C] for 21/9 poloxamer mixture and reduced the gel strength [from 4.03 sec to 3.4 sec] and the mucoadhesive force [from 3.5 to 1.72 x 10[2] dyne/cm[2]]. It was found that the dissolution of DS-loaded poloxamer-based suppositories was significantly higher than that from the conventional suppositories [51.3 versus 26.7%, respectively]. Furthermore, the pharmacokinetic study showed that DS-loaded poloxamer-based suppositories gave significantly higher initial plasma concentrations, AUC [70.313 micro g. hr/ml] and C[max] [29.417 micro g/ml] of DS than did conventional suppositories [55.023 micro g. hr/ml and 22 micro g/ml], respectively. Histopathological study of rectal tissues indicated no pathological damage after 6h of rectal administration. The histopathological study of liver tissues revealed that no hepato-cellular damage occurred after 30 days of administration of DS-loaded poloxamer-based suppository; however hepatotoxicity could not be totally avoided by rectal administration of conventional suppositories. DS-loaded poloxamer-based suppository was an effective rectal dosage form with alleviated adverse effects

Formulation and stability of atropine sulfate eye drops

Atropine sulfate was formulated in ophthalmic solutions using methylcellulose, sodium carboxymethylcellulose, polyvinyl alcohol, polyethylene glycol 6000, and polyvinyl-pyrrolidone K25. The formulations were subjected to stability studies. The obtained results revealed that, no degradation or complexion occur among the tested preparations with the exception of that contained methylcellulose. A significant decrease of drug content and viscosity of the solution was appeared after storage for the first month. Furthermore, the degradation in drug concentration was reached more than 60% after storage at 70C for two years. Also, TLC revealed a chemical decomposition of atropine sulfate in methylcellulose solution

Effect of fluidized bed and high speed mixing granulation on the mechanical properties and bioavailability of trimethoprim

Trimethoprim, an antibacterial insoluble drug, was granulated with 10% aqueous PVP solution using fluidized bed granulator and speed mixing. The granules were evaluated according to flowability, tensile strength and porosity, as well as compressibility after compaction into tablets. The prepared tablets were evaluated according to the physical characteristics of tablets and bioavailability of trimethoprim. The results indicated that on using fluidized bed granulation, porosity of the powder was decreased. Good compressibility and good entirely coated granules with the binder were obtained. On the other h and, tablets prepared by the same method of granulation showed that trimethoprim was equally absorbed at the same rate and extent

Effect of atropine sulfate ointments and gels on the intraocular pressure of rabbit's eye

Atropine sulfate has been formulated in ointments and gels using absorption base, hydrocarbon base, water soluble base, polyvinylpyrrolidone gel and sodium carboxymethylcellulose gel. The release behaviour of the drug and the effect on intraocular pressure of rabbit's eye have been estimated. The results revealed that, the release of atropine sulfate was in the following order, polyvinylpyrrolidone gel > polyethylene glycol > sodium carboxymethylcellulose gel > lanolin-petrolatum > hydrocarbon base. However the maximum effect of drug on intraocular pressure was maintained within three hours in the following order, sodium carboxymethylcellulose gel < hydrocarbon base < polyethylene glycol base < polyvinylpyrrolidone gel < lanolin-petrolatum base

Effect of vehicle composition on bioavailability of atropine sulfate in rabbit's eyes

The effects of vehicle composition on ocular disposition of atropine sulfate was studied using different ophthalmic drops, ointments and gels on rabbit's eyes. The bioavailability of the drug in eye tissues showed that, their distribution were greatly affected by the type of the vehicle. In addition, the uptake by different eye tissues was variable. The peak time of atropine sulfate was found to be 2 hours for ophthalmic drops and 3 hours in case of ointments and gels. The total bioavailability of atropine sulfate in eye tissues of rabbit and aqueous humor after 2 hours were 4350,4010 and 3675 ugm/gm using NaCMC, PVP and PEG ophthalmic drops. While that from ointments and gels after 3 hours were 4355, 4320, 4255 and 4205 ugm/gm for PVP gel, PEG base, hydrocarbon base and NaCMC gel respectively

Formulation and ocular disposition of bromhexine hydrochloride ophthalmic preparations

Bromhexine hydrochloride [BH] a mucolytic agent was formulated in ophthalmic solutions, gels and ointments to be applied topically in the eyes to increase the mucus secretion in case of in flammation and keratoconjunctivitis. The effect of different ophthalmic vehicles, used in these formulation, on the in vitro release and ocular disposition of the drug in rabbit's eye has been studied. The results obtained revealed that, gel formulations [poloxamer 407 and sodium carboxymethylcellulose were superior to all other formulations for improving the ocular bioavailability of the drug. In case of ophthalmic solutions, the peak the time was attained after one hour while the peak level was elevated in the presence of 1% methylcellulose or polyvinyl alcohol. Semisolid vehicles, gels and ointments, exhibited a sustained activity of BH as the peak time was attained after two and three hours, respectively. Highly significant in vitro-in vivo correlations existed

biological activity of saccharomycopsis lipolytica 70551 for citric acid production in a continuous culture

The biological activity of Saccharomycopsis lipolytica 70561, was studied in a chemostate culture at a different dilution rates. The specific rate of sugar uptake and growth were increased with increase of dilution rate reaching its maximum at a dilution rate of 0.02 h-I. The optimal production rate of citric acid was detected at a dilution rate of 0.0114 h-I. Effects of nitrogen concentration on growth, specific production rate, yield factor and productivity of citric acid were also studied

Study on the effect of the combination of propranolol hydrochloride and pilocarpine hydrochloride on intraocular pressure of rabbit's eye

Pilocarpine hydrochloride and /or propranolol hydrochloride were formulated in aqueous solutions and gel form using methyl cellulose and sodium carboxymethylcellulose as thickening and gelling agents, respectively. Both formulations were instilled into normal rabbit's eyes and the changes in the intraocular pressure [IOP] were determined. It was found that the action of both drugs on the intraocular pressure was significantly increased in the presence of the added polymers. Moreover, the optimum decrease in IOP was reached in a shorter time with aqueous solution [2 h] and gel form [3 h] than with control drugs without polymer [4 h]. The peak heights of such decrease were in percentage for pilocarpine hydrochloride 7.2, 27.5 and 17.9, for propranolol hydrochloride 12.5, 18.4 and 17.3 and for their mixture 15.4, 15.4, 15.4 and 16 as aqueous solution, aqueous solution with methylcellulose and gel form, respectively. The study showed that the use of propranolol hydrochloride with pilocarpine hydrochloride with pilocarpine hydrochloride in a concentration of 1% each causes a maximal decrease in IOP in presence of methylcellulose as a thickening agent

Utilization of methanol by yeasts

Four yeast species [Pichia pastoris, Pichia Pinus, Candida boidinii and Hansenula potymorpha] were rows at different concentration of methanol as a sole source of carbon in shake flasks. It was found that the specific growth rate and yield factor varied greatly among the tested strains depending on the methanol concentration. Pichia pastoris CBS 704 was found to be the most efficient strain in the utilization of methanol. Concentrations of methanol greater than 1.5 to 2.0%, retarded growth of Candida boidinii and Pichia pinus. The variation in C/N ratio did not lead to any effect on the methanol consumption rate or on the concentration of formaldhyde in the culture

Growth of pichia pastoris CBS in [704] in fedbatch and continuous cultures

Pichia pastoris [704] was cultivated in fermenters either as fed-batch or continuous cultures using methanol as a sole source of carbon. Results revealed that the addition of microelements and vitamins in 4 equal portions [every 24 hr] to the fermenter increased the utilization efficiency of methanol. The tested yeast had a high affinity for methanol but a low affinity for formaldhyde and least affinity for formate. High low rates in continuous cultures led to a decrease the cell biomass in the fermenter. 02-uptake and C02 production were constant at each dilution rate [steady state] while in fed-batch cultures they gradually increased to reach their maximum at the end of exponential phase, then decrease due to the cessation of growth

Microbodies in methanol assimilating yeast pichia pastoris CBS [704]

The effect of culturing methods on the occurrence of microbodies in the cells of Pichia pastoris CBS 704 was studied. It was found that microbodies were highly affected by culturing methods used for yeast propagation. Growth in shake flasks and fermenter as a batch culture showed smell organelles as well as low numbers of microbodies. Their number and size highly increased when the organism was grown in continuous culture at 0.054h[-1] dilution rate