In vivo pupillary constrictor effects of substance P in man.

The ocular effects of substance P (SP) were studied in 13 normal volunteers. Various concentrations of SP (0.135, 1.35 and 135 micrograms per 100 microliters) were instilled into the conjunctival sac and pupillary area changes were evaluated by means of an electronic pupillometer. The ability of SP to modify the mydriasis induced by pretreatment with 1% homatropine eyedrops was also studied. The instillation of SP produced miosis in a dose-dependent manner without provoking any ocular disturbances. Furthermore, the highest concentration tested was unable to reduce the homatropine-induced mydriasis. These findings indicate that SP exerts a pupillokinetic action in humans which probably occurs via a receptor mechanism. Since muscarinic blockade is not overcome by the peptide instillation, the results do not clarify whether SP causes miosis acting on iris muscles and/or cholinergic fibres.     

Luteal-phase defect induced by deprivation of FSH at a specific period of the follicular phase prevents pregnancy in the bonnet monkey (Macaca radiata)

Female bonnet monkeys were injected i.v. with 25 microliters antiserum to FSH on Days 5, 6 or 7 of the cycle: the length of the luteal phase was shortened but there was no alteration in cycle length. Proven fertile females (N = 6) were caged throughout the period of the experiment (6 cycles) with proven fertile males and treated with 25 microliters FSH antiserum on Day 7 of each of 3 successive cycles. Out of 18 cycle exposures during the treatment phase, 17 were ovulatory, but no pregnancies occurred. In the post-treatment phase, 5 monkeys became pregnant within 3 cycle exposures. These results show that it is possible to render female monkeys infertile by creating luteal insufficiency and this can be achieved repeatedly in a reproducible manner by depriving the cyclic females of FSH support on Day 7 of consecutive cycles.     

Role of cholecystokinin in the intestinal fat- and acid-induced inhibition of gastric secretion.

This study was designed to determine the role of cholecystokinin (CCK) in the inhibition of gastric HCl secretion by duodenal peptone, fat and acid in dogs with chronic gastric and pancreatic fistulas. Intraduodenal instillation of 5% peptone stimulated both gastric HCl secretion and pancreatic protein secretion and caused significant increments in plasma gastrin and CCK levels. L-364,718, a selective antagonist of CCK-A receptors, caused further increase in gastric HCl and plasma gastrin responses to duodenal peptone but reduced the pancreatic protein outputs in these tests by about 75%. L-365,260, an antagonist of type B receptors, reduced gastric acid by about 25% but failed to influence pancreatic response to duodenal peptone. Addition of 10% oleate or acidification of peptone to pH 3.0 profoundly inhibited acid secretion while significantly increasing the pancreatic protein secretion and plasma CCK levels. Administration of L-364,718 reversed the fall in gastric HCl secretion and significantly attenuated pancreatic protein secretion in tests with both peptone plus oleate and peptone plus acid. Exogenous CCK infused i.v. in a dose (25 pmol/kg per h) that raised plasma CCK to the level similar to that achieved by peptone meal plus fat resulted in similar inhibition of gastric acid response to that attained with fat and this effect was completely abolished by the pretreatment with L-364,718. We conclude that CCK released by intestinal peptone meal, containing fat or acid, exerts a tonic inhibitory influence on gastric acid secretion and gastrin release through the CCK-A receptors.     

Oral absorption and excretion of icaritin, an aglycone and also active metabolite of prenylflavonoids from the Chinese medicine Herba Epimedii in rats

Icaritin (ICT) is a main aglycone and also active intestinal metabolite of prenylflavonoids from the Chinese medicine Herba Epimedii. In the present study, the oral absorption and excretion of this compound was investigated using rats for exploring its fate in the body, so as to better understanding its in vivo pharmacological activities. The free (parent) and total (parent plus conjugated metabolites) ICT concentrations in rat plasma, urine and bile, after intravenous (i.v.) and oral administration both at 5mg/kg, were determined before and after enzymatic hydrolysis with β-glucuronidase/sulphatase, respectively, by a HPLC-UV method. The results showed that free ICT plasma concentration after i.v. dose was rapidly decreased with average t(1/2, λ) of 0.43h, while the total ICT concentration was decreased slowly with t(1/2, λ) of 6.86h. The area under the curve of ICT conjugated metabolites was about 11-fold higher than that of free ICT. The majority of ICT in the body was excreted from the bile with 68.05% of dose over 8h after i.v. dosing, in which only 0.15% was in parent form. While very little amount of ICT was excreted from the urine with 3.01% of dose over 24h, in which the parent form was 0.62%. After oral administration, very little amount of parent ICT was detected only in 0.5, 1 or 2h plasma samples with the concentration less than LOQ, however, its total plasma concentration after enzymatic hydrolysis treatment was at relative high level with average maximum concentration of 0.49μg/ml achieved at 1h post dose. The oral bioavailability of ICT was 35% of dose, estimated by its total plasma drug concentrations. It is concluded that ICT can be easily absorbed into the body, and then rapidly conversed to its conjugated metabolites, and finally removed from the body mainly by biliary excretion.     

Ascaris suum: continuous perfusion of the pseudocoelom and nutrient absorption

A double-cannulation apparatus was constructed for continuous perfusion of the pseudocoelom of adult Ascaris suum while maintaining the intact parasite in a controlled incubation chamber. Peristaltic pumps maintained a constant flow rate of artificial perienteric fluid through the incubation chamber (1 ml/min) and through the parasite (100 microliters/min). Based on protein determinations, perienteric fluid was removed from the pseudocoelom within 35 min of initiation of perfusion (3.5 ml). A nonabsorbable dye, Blue Dextran, was detected first in the perfusate 4 min (400 microliters) after initiation of infusion into the pseudocoelom, and was maintained at a constant concentration in the perfusate by 8 min after initiation of dye infusion. Removal of the dye from the pseudocoelom was accomplished within 8 min (800 microliters) after the cessation of dye infusion. Occlusion of the digestive tract had no effect (P less than 0.05) on the short-term (3 hr) absorption of 3H-labeled cholesterol, [14C]-3-o-methylglucose or [14C]glucose from the incubation medium into the perienteric cavity. Concentrations of isotopes in the pseudocoelom reached steady-state levels within 60 min of the initiation of incubation, but remained low (greater than 0.5%) when compared to medium concentration. Similarly, the time course of the accumulation of [14C]glucose into individual tissue components did not differ in intact worms with or without patent intestinal tracts. Thus, the cuticular/muscle tissue largely appears to be the primary route of absorption of cholesterol and glucose in adult A. suum.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of the pharmacokinetics of subcutaneous and intravenous administration of a phosphorothioate oligodeoxynucleotide in cynomolgus monkeys

The pharmacokinetics of subcutaneous (s.c.) administration of a phosphorothioate oligodeoxynucleotide (PS-ODN) was evaluated in cynomolgus monkeys. In a single dose study, monkeys were injected s.c. or intravenously (i.v.) with doses of either 1 or 5 mg/kg ISIS 2302. The bioavailability of s.c. injection ranged from 26% to 55% and appeared to be dependent on the concentration of the dosing solution rather than the dose. The bioavailability of a subcutaneously administered 5 mg/kg dose of ISIS 2302 was 55% using a 50 mg/ml dosing solution and only 26% using a 10 mg/ml dosing solution. Slow absorption from the s.c. injection site significantly blunted the maximal concentration (Cmax) compared with i.v. administration. The time to peak plasma concentration (Tmax) increased slightly with increasing dose, from 0.5 to 1 hour for the 1 mg/kg dose to 1 to 2.5 hours for the 5 mg/kg dose. Plasma half-lives were prolonged after s.c. administration, indicating more dependence on absorption than elimination. The half-lives after s.c. administration averaged 3 hours, whereas after i.v. administration, the half-lives were <1 hour. Metabolism of the ISIS 2302 after s.c. injection was consistent with exonucleolytic cleavage, as previously observed after i.v. administration. In summary, s.c. administration of PS-ODN resulted in prolonged and extensive absorption of the ODN.     

Influence of the composition of rat central lymph on the pharmacokinetics (the steady state during infusion, bioavailability, absorption) of diazepam, studied in the blood and lymph

Diazepam was administered by infusion to three groups of rats with an induced differentiated total lipid content in their lymph (unfed, fed, oil-fed) and its lymph/blood concentration ratios in the steady state were determined. Ratio values were highest in the group with the highest lymph lipid content (the oil-fed group, 2.20 +/- 0.08) and fell significantly in the other groups (fed group 1.46 +/- 0.09, unfed group 1.15 +/- 0.05). The areas under the blood and lymph concentration curves after the intravenous (i.v.) and intraduodenal (i.d.) administration of diazepam were used to determine absolute (F) and lymphatic (FL) bioavailability. The F value in the blood can be raised by increasing the amount of lipids, whereas in the lymph, under the same conditions, it falls. During the i.v. and i.d. administration of diazepam, FL always rises with an increase in the amount of lipids in the lymph. The role played by the lymphatic system in total diazepam absorption was determined from the experimental results of its i.d. administration. The absolute values are very low (0.043-0.316%), but are significantly influenced by the presence of lipids.     

缰核内注射Ca^2＋拮抗电针镇痛的作用可被三碘季铵酚翻转

通过埋植套管向大鼠双侧缰核分别注射0.1mol/L CaCl_2 0.5μl,0.06mol/L ACh0.5μl,5.4×10~(-3)mol/L三碘季铵酚0.5μl和14.4×10~(-3)mol/L阿托品0.5μl后观察到,Ca~(2 )降低基础痛阈并拮抗电针镇痛效应;ACh拮抗电针镇痛;Ca~(2 )拮抗电针镇痛的作用可被胆碱能N受体阻断剂三碘季铵酚完全翻转。提示缰核内的Ca~(2 )可能通过ACh实现其拮抗电针镇痛的效应。     

Improved liquid chromatographic method for mitoxantrone quantification in mouse plasma and tissues to study the pharmacokinetics of a liposome entrapped mitoxantrone formulation

A simple, rapid HPLC method for quantification of mitoxantrone in mouse plasma and tissue homogenates in the presence of a liposome entrapped mitoxantrone formulation (LEM-ETU) is described. Sample preparation is achieved by protein precipitation of 100 microl plasma or 200 microl tissue homogenate with an equal volume of methanol containing 0.5 M hydrochloric acid:acetonitrile (90:10, v/v). Ametantrone is used as the internal standard (i.s.). Mitoxantrone and i.s. are separated on a C18 reversed phase HPLC column, and quantified by their absorbance at 655 nm. In plasma, the standard curve is linear from 5 to 1000 ng/ml, and the precision (%CV) and accuracy (percentage of nominal concentration) are within 10%. In mouse tissue (heart, kidney, liver, lung, and spleen) homogenates (5%, w/v), the standard curve is linear from 25 to 2000 ng/ml, with acceptable precision and accuracy. The method was used to successfully quantify mitoxantrone in mouse plasma and tissue samples to support a pharmacokinetic study of LEM-ETU in mice.     

Intracerebroventricular administration of calcitonin enhances glucose-stimulated release of insulin

Intracerebroventricular (i.c.v.) administration of salmon calcitonin (500 ng) augmented glucose-stimulated release of insulin in rats. Vagotomy increased this enhancement effect of i.c.v. calcitonin significantly, whereas peripheral atropine treatment did not change it. Adrenal catecholamines did not participate in the centrally mediated insulinotropic effect of calcitonin since acute adrenalectomy did not modify the enhancement effect of i.c.v. calcitonin. Destruction of the sympathetic ganglia by neonatal treatment with 6-hydroxydopamine abolished the enhancement effect of i.c.v. calcitonin, which suggests that the sympathetic nervous system participates in the central action of calcitonin to enhance glucose-stimulated release of insulin.     

Systemic delivery of enkephalin peptide through eyes

Leu-enkephalin is one of the important peptides which could become useful drugs in the clinics because of its analgesic action and its availability in mass quantity through biotechnology production. It is found in this study that enkephalin can be effectively absorbed systemically through eyes without using a surfactant as absorption enhancer. Enkephalin at 0.125% (31.25 micrograms/25 microliter) reached a plateau of blood concentration at 11.5 ng/ml in 3-4 hrs and stayed high for 8-9 hrs. In contrast, the blood concentration of enkephalin declined rapidly after i.v. administration with a T1/2 of less than 30 min and reached the lowest point at 22 ng/ml in 5 hrs. With higher concentrations at 1% (.25 mg/25 microliter) and 5% (1.25 mg/25 microliter) similar absorption kinetics was observed except that they reached higher plateau of blood concentration at 72 ng/ml and 233 ng/ml, respectively.     

Secretion of TRH in the third cerebral ventricle during acute cold exposure in the unanesthetized rat. Effect of alpha-adrenergic drugs

The concentrations of TRH in the cerebrospinal fluid (CSF) of the 3rd ventricle were measured with push-pull cannulae in 12 conscious rats. In the basal state the level of TRH in 15 min perfusion samples (210 microliters) were low (2.69 +/- 0.05 pg) and mostly undetectable with the RIA available. However, 70 to 80 min after exposure of the rats to cold (4 degrees C) a short lived but significant rise of TRH was measured in all animals. Post cold peaks amounted to 5.15 +/- 0.5 pg/15 min (p less than 0.001 vs baseline levels). This cold response to CSF TRH was influenced neither by pretreatment of rats with the alpha-adrenergic blocker phentolamine, administered i.p. (40 mg/kg) or i. c. v. (10(-5) M) 1 h before cold exposure, nor by i. c. v. infusion of the alpha 1-adrenergic blocker prazosin (10(-5) M). In rats receiving the blockers the post-cold TRH peaks were 6.76 +/- 1.61 pg/15 min and 5.70 +/- 0.70 pg/15 min, respectively. The possible origin of CSF TRH and the resistance of its cold stimulation to alpha-adrenergic blockers, compared to TRH released into the median eminence are discussed.     

Application of statistical experimental design for optimization of silver nanoparticles biosynthesis by a nanofactory Streptomyces viridochromogenes

Central composite design was chosen to determine the combined effects of four process variables (AgNO₃ concentration, incubation period, pH level and inoculum size) on the extracellular biosynthesis of silver nanoparticles (AgNPs) by Streptomyces viridochromogenes. Statistical analysis of the results showed that incubation period, initial pH level and inoculum size had significant effects (P<0.05) on the biosynthesis of silver nanoparticles at their individual level. The maximum biosynthesis of silver nanoparticles was achieved at a concentration of 0.5% (v/v) of 1 mM AgNO₃, incubation period of 96 h, initial pH of 9 and inoculum size of 2% (v/v). After optimization, the biosynthesis of silver nanoparticles was improved by approximately 5-fold as compared to that of the unoptimized conditions. The synthetic process of silver nanoparticle generation using the reduction of aqueous Ag+ ion by the culture supernatants of S. viridochromogenes was quite fast, and silver nanoparticles were formed immediately by the addition of AgNO₃ solution (1 mM) to the cell-free supernatant. Initial characterization of silver nanoparticles was performed by visual observation of color change from yellow to intense brown color. UV-visible spectrophotometry for measuring surface plasmon resonance showed a single absorption peak at 400 nm, which confirmed the presence of silver nanoparticles. Fourier Transform Infrared Spectroscopy analysis provided evidence for proteins as possible reducing and capping agents for stabilizing the nanoparticles. Transmission Electron Microscopy revealed the extracellular formation of spherical silver nanoparticles in the size range of 2.15–7.27 nm. Compared to the cell-free supernatant, the biosynthesized AgNPs revealed superior antimicrobial activity against Gram-negative, Gram-positive bacterial strains and Candida albicans.     

Factors affecting survival of mouse blastocysts vitrified by a mixture of ethylene glycol and dimethyl sulfoxide

The present study was conducted to determine suitable conditions for mouse blastocysts vitrified by a solution containing 25 % v/v (4.5M) ethylene glycol and 25% v/v (3.4M) dimethyl sulfoxide (VSi). In Experiment 1, blastocysts were exposed to 50% diluted VSi (50% VSi) for 10 minutes then to VSi for 0.5 minutes at room temperature (22 approximately 24 degrees C) or at 4 degrees C, followed by vitrification. The survival rates of these embryos exposed at each temperature were not significantly different. In Experiment 2, embryos were exposed directly to VSi for various time periods at room temperature and diluted in mPBS with 0.5 M sucrose without vitrification. The viability of embryos decreased after more than a 3 minute exposure. When the embryos were exposed to VSi for 0.5, 1, 1.5 and 2 minutes followed by vitrification, the survival rates were 78, 80, 76 and 50%, respectively. In Experiment 3, embryos were vitrified after exposure to 50% VSi for various time periods and then to VSi for 0.5 minutes at room temperature. One minute exposure to 50% VSi resulted in the highest survival rate. In Experiment 4 and 5, the cooling rate (from approximately 70 to approximately 2500 degrees C/minute), sucrose concentration (0, 0.5 and 1 M) of dilution solution, and dilution time (1 or 5 minutes) did not affect the viability of the vitrified embryos. Following exposure to 50% VSi for 1 minute and to VSi for 0.5 minutes at room temperature, embryos were cooled 1) at approximately 2500 degrees C/minute and diluted in 0.5 M sucrose in mPBS after warming or 2) at approximately 200 degrees C/minute and diluted in mPBS. In vivo development rates after the transfer to recipients were 38 and 42%, respectively. These values were similar to that of fresh control embryos.     

Calcium rather than calcitonin is dominant to mediate gastric emptying in thyroidectomized rats

Both calcium and calcitonin are important in mediating gastrointestinal motility. Present study tried to study what was the dominant role of calcitonin or calcium replacement on the gastric emptying in thyroidectomized animals. Adult Sprague-Dawley male rats received thyroidectomy or sham operation and then housed for two weeks until motility study, which was conducted using radiochromium to measure gastric emptying. Before motility study these rats were i.p. injected with saline or human calcitonin in the doses of 0.1, 1 and 10 microgM/kg, respectively. Another group of thyroidectomized rats received i.v. infusion of saline or CaCl2 for 30 min before motility study. Among thyroidectomized rats, neither saline nor various doses of calcitonin treatment disturbed gastric emptying compared to this of sham operated rats. Thyroidectomy diminished plasma calcium level, however, additional calcitonin treatment did not restore the suppressed calcium level (P<0.01). Of rats following saline or CaCl2 infusion, thyroidectomy did not change gastric emptying, whereas CaCl2 infusion enhanced gastric emptying (P<0.05). In conclusion, exogenous calcium treatment further enhances gastric emptying in thyroidectomized rats, whereas calcitonin replacement has no effect on gastric emptying. We suggest that calcium rather than calcitonin is dominant to mediate gastric emptying.     

Identification and characterisation of the Mpeg1 homologue in the South African abalone, Haliotis midae

Although Haliotis midae is the most economically important cultured abalone species in South Africa, infectious diseases have the potential to severely limit the production of this shellfish. Consequently, it is becoming increasingly important to characterise the abalone immune system in order to better understand their ability to combat infection. This study reports the identification and characterisation of a perforin-like protein, designated hmMpeg1, which is believed to be involved in the H. midae immune system. hmMpeg1 encodes for a 78 kDa protein that has significant sequence similarity to Mpeg proteins from other abalone species and includes the conserved cytolytic membrane attack complex/perforin (MACPF) domain of perforin. Real-time quantitative PCR (qPCR) analysis demonstrated expression of hmMpeg1 mRNA in haemocytes and epipodia samples from H. midae exposed to a heat-killed, Gram-negative bacterial pathogen, Vibrio anguillarum 5676. hmMpeg1 mRNA in haemocytes increased significantly 48 h post-infection (h.p.i) (8.2 fold; P < 0.05), coinciding with a decrease in the total number of circulating haemocytes, and reached a maximum at 96 h.p.i (17.2 fold; P < 0.05). Similarly, a significant increase in the level of hmMpeg1 mRNA occurred at 24 h.p.i in epipodia samples (3.8 fold; P < 0.05), reaching a maximum at 48 h.p.i (4.5 fold; P < 0.05). In addition, western blot analysis detected a significant increase in hmMpeg1 between 24 h.p.i (4.2 fold; P < 0.05) and 48 h.p.i (3.1 fold; P < 0.05) in the epipodia, and between 48 h.p.i (1.7 fold; P < 0.05) and 96 h.p.i (1.9 fold; P < 0.05) in haemocytes, sampled from abalone exposed to the abalone pathogen V. anguillarum 5676. The importance of hmMpeg1, in terms of its function and importance in the H. midae immune response, is discussed.     

A method for intratracheal instillation of endotoxin into the lungs of mice

A detailed method is presented for the intratracheal instillation of fluids into the lungs of mice. Using 125I-albumen it was determined that 25-50 microliters of volume gave almost equal distribution to all lobes of the mouse lung. Extremely low levels of endotoxin given intratracheally (12.5-25 ng) resulted in a dramatic increase in the neutrophil content of the lung. The increase started in less than 4 h, reaching levels of 7 x 10(5) by 18 h and was maintained at elevated levels for at least 48 h. This neutrophil count represented more than 90% of the cell population of the lung.     

第三脑室注射组胺及其受体激动剂对五肽促胃液素诱导...

The present study shows the dual effects of intraventricularly injected histamine (0.25-2.0 micrograms/5 microliters) on pentagastrin-induced gastric acid secretion. Male Wistar rats weighing 200-300 g were anesthetized with intraperitoneal sodium pentobarbital. Gastric acid was continuously washed out with 37 degrees C saline solution by means of a perfusion pump. On the background of continuous intravenous infusion of pentagastrin [7.5 micrograms/(kg.h),] histamine (0.25 microgram/5 microliters) or 2-pyridylethylamine (PEA, 10 micrograms/5 microliters), a H1-receptor agonist, was injected into the third ventricle through a chronically implanted canula. The acid output decreased 10 min after injection and did not recover at 90 min. When the dose of histamine was increased to 1.0 micrograms or 2.0 micrograms, dual effects appeared. The acid output decreased respectively in 73% or 50% of the animals, while in the rest 27% and 50% of the animals, the acid output increased. H2-receptor agonist dimaprit (10 micrograms/5 microliters, i.c.v.) or impromidine (0.1 micrograms/5 microliters, i.c.v.) had no pronounced effect on pentagastrin-induced acid secretion. Pretreatment with diphenhydramine (16 micrograms/0.2 ml or 32 micrograms/0.2 ml, i.m.) abolished the inhibitory effect of histamine and PEA on acid secretion. These results suggest that histamine may be involved in the central regulation of gastric acid secretion, and the inhibitory effect may be mediated by H1-receptors in the brain. The mechanism underlying the production of the dual effects of histamine is unknown.     

The utility of 2-hydroxypropyl-beta-cyclodextrin as a vehicle for the intracerebral and intrathecal administration of drugs.

The substituted glucopyranose ring structure 2-hydroxypropyl-beta-cyclodextrin (CDEX) increases the solubility of molecules by inclusion of the agent in the lipophilic interior of the ring. This property is of particular use for the administration of molecules by the intracerebral (ICV) or intrathecal (IT) routes. In concentrations up to 40% w/v (isotonic), this agent (10 microliters) effect upon nociceptive or motor function after IT injection or on EEG and general behavior after ICV injection in rats. Using 20% CDEX, there is no change in the ED50 as compared to saline on the hot plate (HP) after IT injection of morphine, D-Ala2-D-Leu5 enkephalin or Tyr-Aib-Gly-gPhe-mAib-NH2, (Aib: alpha-aminoisobutyric acid) although there is an increase in their respective durations of effect. Cyclic peptide opioids: Tyr-c[D-A2bu-Gly-D-beta Nal(1)-D-Leu] (A2bu: alpha, gamma-diaminobutyric acid; beta-Nal(1): beta-naphthylalanine(1)) or Tyr-c[DA2bu-Gly-beta Nal(1)-D-Leu] are insoluble in saline but are readily dissolved in CDEX, and display a naloxone-sensitive antinociception following spinal administration. In other studies, saline insoluble capsaicin is administered in 25% dimethylsulfoxide (DMSO) or 20% CDEX (15 microliters; 5 mg/ml) which result in a significant reduction in the spinal levels of substance P and calcitonin gene related peptide and an increase in the HP latency. DMSO alone, but not CDEX alone, reduces the levels of the two peptides. These data emphasize the utility of complexation with CDEX for intracerebral drug delivery and compatibility with brain and spinal tissue.     

The performance of anion exchange expanded bed adsorption chromatography on the recovery of G6PDH from unclarified feedstock with high biomass concentration

The bed stability of Streamline DEAE (p=1.2 g/mL) in a 20 mm (i.d.) glass expanded bed contactor, and its performance on the recovery of glucose 6-phosphate dehydrogenase (G6PDH) from unclarified yeast homogenate were investigated. A residence time distribution study showed that a stable expanded bed was achieved. The theoretical plate and Bodenstein numbers determined were 25 and 53, respectively. A recovery yield of 87% and purification factor of 4.1 were achieved in the operation using 5% (w/v) biomass concentration feedstock. The performance of the anion exchange EBAC was still considerable good at a biomass concentration as high as 15% (w/v).