Screening the elite chemotypes of Gloriosa superba L. in India for the production of anticancer colchicine: simultaneous microwave-assisted extraction and HPTLC studies.

BACKGROUND: Gloriosa superba L. (Colchicaceae) is a high-value medicinal plant indigenous to Africa and Southeast Asia. Its therapeutic benefits are well-established in traditional medicines including Ayurveda. It is well known for its natural bioactive compound colchicine which exhibits a wide range of pharmacological activities i.e. rheumatism, gout and was also introduced into clinical practices. The increasing demand as well as its illegal harvesting has brought this valuable plant under threatened category. METHODS: The present investigation describes a microwave assisted extraction (MAE) strategy coupled with a densitometric-high performance thin layer chromatographic (HPTLC) methodology for the analysis of colchicine from 32 different populations of G. superba. A Box-Behnken statistical design (3 level factor) has been employed to optimize MAE, in which power of microwave, time of irradiation, aqueous ethanol and pH were used as independent variables whereas colchicine was used as the dependent variables. Chromatography was carried out on Silica gel 60 F254 TLC plates with toluene: methanol, 85:15 (v/v) being used as solvent system. Densitometric measurement was performed at λ=254 nm following post-derivatization (10% methanolic sulphuric acid). RESULTS: Optimal conditions for extraction to obtain the maximum colchicine yield was found to be 7.51 mg g- 1 which was very close to be predicted response 7.48 mg g- 1 by maintaining microwave power (460 W), irradiation time (6.4 min), aqueous ethanol-30, pH -3. Colchicine content ranged between 2.12-7.58 mg g- 1 among 32 G. superba populations in which only three chemotypes viz. GS- 1, GS- 3, and GS- 2 collected from West Bengal and Sikkim, respectively exhibited maximum yield of colchicine. CONCLUSION: Therefore, this newly developed optimized MAE coupled with HPTLC densitometry methodology not only quantifies colchicine in order to identify elite chemotypes of G. superba, but it also encourages in selecting high yielding populations of the plants for industrial use and economic boost for the farmers. This validated, simple and reproducible HPTLC protocol is being used for the first time to estimate colchicine from natural populations of G. superba obtained from 32 different geographical regions of India.

First Observation of Multiple Transverse Wobbling Bands of Different Kinds in

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

Prevalence and Symptom Correlation of Lactose Intolerance in the North East Part of Bangladesh.

This study was designed to see the prevalence of lactose intolerance and symptom correlation following oral lactose challenge in healthy volunteers in the north east part of Bangladesh. Symptoms of abdominal pain, nausea, borborygmi, flatulence, diarrhea and others were noted for 24 hours and blood glucose was estimated at 0 hour and 30 minutes after 50 gm oral lactose load to healthy volunteers. Failure to rise blood glucose level ≥1.1 mmol/l at 30 minutes after lactose intake from fasting level was taken as lactose malabsorption (LM) i.e., lactose intolerance. Sensitivity and specificity of different symptoms were then found out. A total of 171 volunteers (male 123, female 48) with a mean age 34.08 years participated in this study. Lactose intolerance was found among 82.5% (n=141, M=100, F=41) subjects. Symptoms mostly experience by the lactose malabsorbers were diarrhea 93(66.0%), borborygmi 80(56.7%), abdominal pain 31(22.0%) and flatulence 32(22.7%). LM prevalence was found to increase with increasing number of symptoms up to 3 symptoms. A week positive correlation (r=0.205, P=0.007) was found between the number of symptoms and proportion of subjects having positive lactose tolerance test. Lactose intolerance among healthy adults of North East part of our country is as common as in other Asian countries including China and Malaysia. But LM is higher than that of Europeans and south Indians. Diarrhea and borborygmi were mostly associated with LM.

Initial Experience with Endoscopic Ultrasound.

Since its introduction in early 1990s, endoscopic ultrasound (EUS) has become integral to the diagnosis and staging of various luminal, extraluminal gastrointestinal (GI) and certain non-GI lesions. There is no data on EUS experience in Bangladesh. The aim of this paper is to evaluate the initial recent experience and clinical impact of EUS. All EUS procedures data were recorded prospectively from July 2013 to December 2014. These included patients' demographics, referral details, provisional diagnosis, management plan before and after EUS & indications of procedures. EUS-FNA data recorded included details regarding site, number of passes and histological diagnosis. Two hundred & four EUS procedures were carried out over one and half years. Male female ratio was 1.4:1, mean age was 46.4 ± 20 years. Of these procedures 148 (72.5%) were referrals from physicians and 56 (27.5%) were from surgeons. Most common indications were pancreatobiliary pathologies, esophageal & gastric pathologies. Pancreatobiliary lesions (n = 165, 80.9%) included patients with (A) Benign pathologies: Microliths in Gall baldder (n = 6), Gall stones (n = 12), Biliary ascarrisis (n = 22), Choledocholithiasis (n = 42), Acute Pancreatitis (n = 9), Chronic Pancreatitis (n = 15), Pancreatic pseudocysts(n = 4) (B) Malignant Pathologies : GB Carcinoma (n = 4), Cholangiocarcinoma (n = 29), Ca- pancreas (n = 9), Periampullary carcinoma (n = 12). Esophageal lesion was 9.3% (n = 19) of total procedures. Forty seven percent (n = 9) of EUS procedures on esophagus were for staging of esophageal malignancy, 10. 5% (n = 2) for restaging or recurrence after chemoradiation and 21% (n = 4) for submucosal lesions. Fifteen EUS procedures were carried out for gastric lesions, seven were for staging of gastric carcinoma, four were for assessment of submucosal lesions (e.g. GIST, lipoma or external compression), 02 for assessment of polyps and two for gastric ulcers.In clinical impact & outcome study, changes in diagnosis, management, avoidance of investigations and usefulness of EUS were evaluated. Diagnosis was changed in 34.4% (64/186) & management was changed in 45%(92/204). Additional investigation was avoided in 57.8% (118/204). This is the first report of Bangladesh experience of EUS to date. EUS is safe, accurate, cost effective & very useful tool for diagnosis and management of G.I. disorders.

Double balloon enteroscopy: Bangladesh experience.

Double balloon enteroscopy (DBE) is a newly developed endoscopic modality for diagnosis and treatment of small bowel disorders. The aim of this study was to evaluate the diagnostic and therapeutic impact of DBE in patient with suspected small bowel disease. This was a prospective study. Sixty one double balloon enteroscopy procedures (30 antegrade 31 retrograde) were done in thirty six patients (20M/16F, mean age 40 ± 12.5 range 16-65 years ) at gastroenterology department, Sir Salimullah Medical College, Dhaka between October 2011 and September 2012. Indications for DBE included chronic abdominal pain 14 (38.9%), obscure GI bleeding 11 (30.56%), Small bowel obstruction 05 (13.89%), and chronic diarrhea 06 (16.67%). The morphologic findings were ulcerations 13 (36.11%), growth 03 (8.33%), vascular ectasia 03 (8.33%) and polyp 01 (2.78%). Therapeutic interventions were performed in one patient only. No serious complications were observed. Diagnostic yields in case of chronic abdominal pain, chronic diarrhea, obscure GI bleeding and small bowel obstruction were 50%, 66%, 63% and 40% respectively. The findings were adenocarcinoma 04 (11%), lymphoma 03 (8.4%), tuberculosis 03 (8.4%), non specific findings 05 (13.9%), IPSID 01(2.8%), Crohn's disease 01 (2.8%), vascular ectasia 03 (8.33%) and normal 16 (44.44%). DBE is well tolerated, feasible and useful technique for the diagnosis as well as treatment of small intestinal disorders.

Effect of Application of Platelet-Rich Plasma on Bone Regeneration after Removal of Jaw Cysts.

Platelets are involved in regeneration at sites of bony defect, apart from their function in coagulation. An autologous preparation platelet-rich plasma gel applied to sites of bony defects after surgical treatment of jaw cyst. This case-control study was conducted in Bangabandhu Sheikh Mujib Medical University (BSMMU) in the department of Oral and Maxillofacial Surgery from September 2017 to August 2018. Total 30 patients were chosen having jaw cyst. They were divided into 2 groups; Group A and Group B, where Group A got the platelet rich plasma, after removal of the cystic lesion; and Group B got the normal usual treatment. Platelet rich plasma gel was prepared using a standardized technique and applied to the surgical site of the Group A. The differences of radiographic changes between the two groups at 6th, 12th, 18th and 24th weeks after surgery were analyzed. Study showed significant changes in early bone regeneration in group A at 12th and 18th weeks post operatively. Platelet rich plasma induces early bone regeneration and it has proven successful outcome.

Effect of Full Veneer Crown on Periodontal Health in Diabetic and Non-Diabetic Patients.

Both periodontal disease and diabetes mellitus (DM) are important public health issues. Compared to the non-diabetic counterparts, diabetic patients more often suffer from dental problems, sometimes requiring fixed-dental prosthesis. Gingival inflammation and other forms of periodontal disease are the common complications of the dental prosthesis. This prospective comparative experimental study was intended to compare the outcome of the periodontal health after placement of full veneer crown in diabetic and non-diabetic patients in the Department of Prosthodontics, Faculty of Dentistry, Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh from April 2018 to March 2019. This study involved consecutive 53 diabetic and 53 non-diabetic adult patients of either sex, undergoing treatment with full veneer crown in either maxillary or mandibular posterior teeth with healthy periodontal tissue. The outcome variables were: plaque index, gingival index, periodontal pocket depth, and bleeding on probing, at baseline, 3 months and 6 months post-procedure. Gingival index in the diabetic group reached from 0 at baseline to nearly 0.1 at 3 months which then steeply reached to 0.2 at 6 months interval, whereas the same index in the non-diabetic group reached from 0 at baseline to 0.009 at 3 months and 0.04 at 6 months interval. Plaque index of diabetic patients increased from 0 at baseline to 0.5 at 3- and 6-months interval, whereas the plaque index of non-diabetic patients increased to 0.4 at 3 months and then decreased again 0.3 at 6 months interval (p<0.001). Periodontal pocket depth of diabetic group increased from 1.0mm at baseline to 1.2 and 1.5mm at 3 and 6 months respectively, while the same measure in the non-diabetic group increased to 1.1 and 1.3mm at 3 and 6 months respectively (p<0.001). Bleeding on probing index in the diabetic group reached sharply to 1.5 at 3 months from 0 at baseline and then it reached 2.3 at 6 months, whereas the same index in non-diabetic group reached 1.1 and 1.6 at 3 and 6 months respectively (p<0.001). Periodontal health outcome of full veener crown in diabetic patients is adversely affected compared to that in non-diabetic patients.

Pancreatobiliary Diseases: Evaluation by Transabdominal and Endoscopic Ultrasound.

Pancreaticobiliary diseases are the important causes of morbidity and mortality worldwide. Among the imaging modalities, Transabdominal ultrasound (TUS) is cheap, available, and noninvasive but it has some limitations. Endoscopic ultrasound (EUS) is invasive but it has some diagnostic and therapeutic advantages over TUS. This study was aimed to see the diagnostic yields of EUS and TUS in the pancreatobiliary diseases. This cross sectional study was conducted in Sir Salimullah Medical College Mitford Hospital (SSMC&MH), Dhaka, Bangladesh from March 2017 to February 2019. All (n=222) patients were evaluated clinically and with relevant investigations. TUS and EUS were done in all patients. Endoscopic retrograde cholangiopancreatography (ERCP) was done in 60 patients. Among 222 patients 56.8% were males; mean age was 46±16 years; the main presenting symptoms were abdominal pain and jaundice. In diseases of biliary tree, EUS showed dilated CBD alone or in combination with stone in 50 and 67 cases and TUS showed 37, 63 patients respectively. The difference between the findings of EUS and TUS was statistically significant (p=0.00). In gall bladder, EUS found microlithiasis in 6(2.6%) and sludges in 24(10.8%) cases whereas TUS found microlithiasis in 1(0.5%) and sludges in 17(7.7%) cases respectively (p=0.00). Both EUS and TUS detected cholelithiasis in equal number of patients 46(20.3%). On pancreatic evaluation, EUS and TUS detected pancreatic parenchymal abnormalities in 24(10.8%) and 12(5.5%) patients respectively with significant p value (0.00). In cases of pancreatic and cholangiocarcinoma the difference between the findings of EUS and TUS were statistically significant (p<0.05). EUS detected 7 cases of ampullary/peri-ampullary neoplasms whereas TUS detected only 2 cases. The sensitivity of EUS for detecting CBD dilatation, CBD stones, CBD SOL and pancreatic SOL was 85%, 91%, 93%, and 92% respectively. The sensitivity of TUS for detecting CBD dilatation, CBD stones, CBD SOL and pancreatic SOL was 42%, 52%, 40%, and 37% respectively. EUS is more sensitive than TUS in diagnosing pancreaticobiliary disorders. It is of paramount importance in patients in diagnosing CBD dilatation, choledocholithiasis, biliary microlithiasis and pancreaticobiliary neoplasm. EUS has important role before proceeding to further management by more invasive techniques like ERCP or surgery.

Histopathological changes in different stages of alopecia areata.

Alopecia areata is a common disorder affecting any of the hair bearing areas of the body. Most of the cases are diagnosed on the clinical ground only. Histopathological changes may help in the diagnosis in difficult cases. The present study was designed to observe the histopathologic changes of alopecia areata at different stages. Thirty consecutive patients suffering from alopecia areata were enrolled. Face to face interview was performed using a structured pre-tested questionnaire. At the initial visit, one 4mm punch scalp biopsy specimen was taken from an area of hair loss. Biopsy specimens were sent in a test tube filled with formalin to the department of Pathology, Bangabandhu Sheikh Mujib Medical University (BSMMU) where tissue was processed, sectioned and slides were prepared. Haematoxylin and eosin stains were used. Aanagen hairs were decreased in all stages of alopecia areata. Telogen hairs increased in acute and chronic stages whereas catagen hairs increased markedly in sub-acute stage. Although miniaturized (atrophic) follicle was frequently found in chronic stage. It was absent in acute and sub-acute stages. Moderate to dense peribulbar infiltration of lymphocytes were observed in acute stage and mild to moderate infiltration in sub-acute stage. In chronic stage either no or mild infiltrations were observed. Peribulbar infiltration of eosinophils and macrophages were seen in all stages of alopecia areata. Alopecia areata can be diagnosed with some confidence, even when inflammatory infiltrate is absent, based on increased numbers of telogen hairs in the acute and chronic stages, increased miniaturized hairs in chronic stage and markedly increased catagen hairs in sub-acute stage.

Comparative Study of Alginate and Omeprazole in Symptomatic Treatment of Non-erosive Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease is widely reported most prevalent disease of the gastrointestinal tract. The burden of gastroesophageal reflux disease (GERD) is increasing in Asia and the majority of patients have non-erosive reflux disease. This prospective, open label, non random (consecutive), experimental study was performed due to compare the therapeutic efficacy of alginate and omeprazole in relieving symptoms of non erosive reflux disease (NERD) and was carried out in the Outpatient Department of Gastroenterology, Dhaka Medical College Hospital, Dhaka, Bangladesh from December 2013 to May 2014. Sixty patients were enrolled for this study and were divided into two groups. Among them, 30 subjects were assigned to the omeprazole group (Group I) and 30 subjects to the alginate group (Group II). Omeprazole 20mg enteric coated capsule daily and alginate 10ml three times daily were administered 14 days in this study. In ITT analysis, achieving complete symptom relief (heart burn) was 56.7% in alginate group & 60% in omeprazole group. Statistically which was not significant (p=0.793). In PP analysis, this was 65.4% and 66.7% respectively. In this study, the overall satisfaction of omeprazole & alginate was more than 86% and the mean duration of heart burn free was found 5.0±4.0 days in Group I and 3.65±2.8 days in Group II. The difference was not statistically (p>0.05) significant between two groups in this study. Therapeutic efficacy and safety profiles of alginate were comparable to omeprazole after two weeks treatment in NERD subjects. So alginate may be considered as a relevant and effective alternative medication in non-erosive reflux.

Optimization of nutrients for gellan gum production by Sphingomonas paucimobilis ATCC-31461 in molasses based medium using response surface methodology.

A molasses based medium for the production of gellan by Sphingomonas paucimobilis ATCC-31461 was developed. Placket-Burman design criterion was applied to study the effect of various nutrient supplements on gellan production using molasses. Among the 20 variables tested, molasses, tryptone, casaminoacid, disodium hydrogen orthophosphate and manganese chloride showed significant effect on gellan production. A central composite design was applied to determine the optimum concentrations of the significant variables obtained from Placket-Burman design. Most suitable medium composition for production of gellan was (g/l): molasses-112.5; tryptone-1; casaminoacid-1; disodium hydrogen orthophosphate-1; manganese chloride-0.947 and the optimum gellan production was 13.814 g/l.

Differences between the Lewis and Sprague-Dawley rats in chronic inflammation induced norepinephrine sensitivity of cutaneous C-fiber nociceptors.

We investigated whether there are any differences between the Lewis and Sprague-Dawley (SD) rats in chronic inflammation-induced norepinephrine (NE) sensitivity of nociceptors. Activities of C-fiber nociceptors innervating rat hairy hindpaw skin were recorded in an in vitro skin-nerve preparation. Sixty-five percent of C-fibers from inflamed Lewis rats were excited by NE (10 microM), against only 38% of C-fibers from inflamed SD rats. The average of the total impulses evoked in response to NE was also significantly higher in Lewis rats. The alpha2-adrenoceptor antagonist CH 38083 (10 microM) and yohimbine (10 microM) consistently blocked the NE-excitation of both strains. These results show that after chronic inflammation, C-fiber nociceptors of Lewis strain rats have a stronger sensitivity to NE, and that alpha2-adrenoceptors are predominately involved in the NE-sensitivity of inflamed rats in both strains.

Retrocorneal membrane with Descemet's detachment.

PURPOSE: To describe a unique case of retrocorneal membrane with large Descemet's detachment. METHODS: Case report of a 65-year-old man reported intermittent cloudy vision in his left eye. The patient underwent serial ocular examinations and slit-lamp photography over 6 weeks. RESULTS: The patient had an inflammatory-appearing membrane that covered 60% of the posterior cornea, with a subtotal Descemet's detachment. Vision was stable at 20/20, and the cornea remained clear. The patient was empirically treated with topical neomycin/polymyxin/dexamethasone, sodium chloride, and oral acyclovir, and his symptoms improved; however, the retrocorneal membrane persisted. CONCLUSION: This unusual clinical finding may represent reduplicated Descemet's membrane with partial Descemet's detachment secondary to occult deep herpes simplex keratitis. Other possibilities include spontaneous or traumatic Descemet's tear and detachment.

Improved growth and colchicine concentration in Gloriosa superba on mycorrhizal inoculation supplemented with phosphorus-fertilizer.

BACKGROUND: Gloriosa superba produces an array of alkaloids including colchicine, a compound of interest in the treatment of various diseases. The tuber of Gloriosa superba is a rich source of colchicine which has shown anti-gout, anti-inflammatory, and anti-tumor activity. However, this promising compound remains expensive and Gloriosa superba is such a good source in global scale. Increase in yield of naturally occurring colchicine is an important area of investigation. MATERIALS AND METHODS: The effects of inoculation by four arbuscular mycorrhizal (AM), fungi, Glomus mossae, Glomus fasciculatum, Gigaspora margarita and Gigaspora gilmorei either alone or supplemented with P-fertilizer, on colchicine concentration in Gloriosa superba were studied. The concentration of colchicine was determined by high-performance thin layer chromatography. RESULTS: The four fungi significantly increased concentration of colchicine in the herb. Although there was significant increase in concentration of colchicine in non-mycorrhizal P-fertilized plants as compared to control, the extent of the increase was less compared to mycorrhizal plants grown with or without P-fertilization. This suggests that the increase in colchicine concentration may not be entirely attributed to enhanced P-nutrition and improved growth. Among the four AM fungi Glomus mossae was found to be best. The total colchicine content of plant (mg / plant) was significantly high in plants inoculated with Glomus mossae and 25 mg kg(-1)phosphorus fertilizer (348.9 mg /plant) while the control contain least colchicine (177.87 mg / plant). CONCLUSION: The study suggests a potential role of AM fungi in improving the concentration of colchicine in Gloriosa superba tuber.

Biochemical characterization and antitumor study of L-glutaminase from Bacillus cereus MTCC 1305.

L-Glutaminase (E.C.3.5.2.1) extracellularly produced by Bacillus cereus MTCC 1305 was purified to apparent homogeneity with a fine band. The molecular weight of native enzyme and its subunit were found to be approximately 140 and 35 kDa, respectively, which indicates its homotetrameric nature. The substrate specificity test of this enzyme showed its specificity for L-glutamine. The purified enzyme showed maximum activity at optimum pH 7.5 and temperature 35 °C. The enzyme retained stability up to 50 and 20 % even after treatment at 50 and 55 °C, respectively, for 30 min. Monovalent cations (Na(+), K(+)) and phosphate ion activated the enzyme activity, while divalent cations (Mg(2+), Mn(2+), Zn(2+), Pb(2+), Ca(2+), Co(2+), Hg(2+), Cd(2+), Cu(2+)) inhibited its activity. Reducing agents (cysteine, glutathione, dithiothreitol, L-ascorbic acid, and ß-mercaptoethanol) stimulated its activity, whereas thiol-binding agents (iodoacetamide, p-chloromercuribenzoic acid) resulted in the inhibition of this enzyme. Kinetic parameters, K m, V max, K cat, of purified enzyme were found to be 6.25 mM, 100 µmol/min/mg protein and 2.22 × 10(2) M(-1)s(-1), respectively. The gradual inhibition in growth of hepatocellular carcinoma (Hep-G2) cell lines was found with IC50 value of 82.27 µg/ml in the presence of different doses of L-glutaminase (10-100 µg/ml).

Inhibition of tumor cells proliferation and migration by the flavonoid furin inhibitor isolated from Oroxylum indicum.

BACKGROUND: The medicinally active plant Oroxylum indicum (OI) has drawn considerable research interest because of its many observed biological activities. Of particular interest is its antitumorigenic activity. The plant is a rich source of flavonoids and their glycosides. Recently flavonoids have been described as inhibitors of kexin-type proteases of superfamily Proprotein Convertase Subtilisin/ Kexins (PCSKs) which have been implicated in tumor growth and malignancy. These enzymes particularly furin (PCSK3) cleaves inactive precursor growth factors into their mature forms that promote tumor growth. As a result, finding furin-inhibitors became of high interest in cancer research. In this regard, the plant OI with known anticancer activities may provide an important source. OBJECTIVE: The objective of this study is to examine and compare anti-tumorigenic activity of furin inhibitory flavonoid compounds from OI. RESULTS: Studies were conducted to evaluate the effect on CT-26 cell proliferation and migration of 4 flavonoids baicalein, chrysin, oroxylin-A and its glycoside isolated from OI. Data revealed that baicalein exhibited most potent inhibitory effect on proliferation and migration on the analyzed tumor cell line. Baicalein at 10 µM completely blocked the proliferation even after 5 days. The results are consistent with the observed in vitro anti-furin activity of baicalein as measured against a fluorogenic peptide and pro-hVEGF-C as substrates. Mature VEGF-C is a strong indicator and biomarker of tumor progression and therefore the antifurin activity may explain the observed anticancer properties of baicalein. Since baicalein is the major constituent of OI, our data provided scientific rationale for the observed anticancer activity of OI and also offered a new lead molecule for future exploration as potential antitumor agents.

Extractive fermentation for enhanced production of alkaline phosphatase from Bacillus licheniformis MTCC 1483 using aqueous two-phase systems.

A study was made to find out maximum partitioning of Bacillus licheniformis alkaline phosphatase in different ATPSs composed of different molecular weight of PEG X (X=2000, 4000, 6000) with salts (magnesium sulphate, sodium sulphate, sodium citrate) and polymers (dextran 40, dextran T500). Physicochemical factors such as effect of system pH, system temperature and production media were evaluated for partitioning of alkaline phosphatase. PEG 4000 [9.0% (w/v)] and dextran T500 [9.6% (w/v)] were selected as most suitable system components for alkaline phosphatase production by B. licheniformis based on greater partition coefficient (k=5.23). The two-phase system produced fewer enzymes than the homogeneous fermentation (control) in early stage of fermentation, but after 72 h the enzyme produced in the control system was less than that in the ATPS. Total alkaline phosphatase yield in ATPS fermentation was 3907.01 U/ml and in homogeneous fermentation 2856.50 U/ml.

Proprotein convertase inhibitory activities of flavonoids isolated from Oroxylum indicum.

BACKGROUND: Proprotein Convertases (PCs) or Proprotein Convertase Subtilisin/Kexins (PCSKs) belong to a family of calcium-dependent endoproteases that are structurally related to bacterial subtilisin and yeast kexin. These enzymes play major roles in the processing of inactive precursor proteins producing their bioactive mature forms that are implicated in a wide variety of diseases including cancer, viral and bacterial infections. As a result, PCs are major targets for intervention of these diseases. OBJECTIVE: Our objective in this study is to find non-peptide inhibitors of PC-enzymes from a potential natural source. RESULTS: Herein we describe several natural flavonoid compounds as inhibitors of PC-enzymes including furin, a key member. These compounds were isolated from the medicinal plant Oroxylum indicum, fully characterized and tested in vitro for their PC-inhibitory property against the fluorogenic peptide substrate, Boc-RVRR-MCA (Boc = tert-butyloxy carbonyl, MCA = 4-methyl coumarin7-amide). The measured Ki and IC50 were found to be in low microM ranges. A comparative analysis of inhibition against furin, PC4, PC5 and PC7 suggested a partial selectivity towards PC4. These flavonoids also blocked efficiently the PC4-mediated processing of a fluorogenic peptide derived from the processing site of its substrate, pro-Insulin Growth Factor-1 (proIGF-1). This anti-protease activity may provide a rationale for the observed anticancer and anti-HIV properties of some of these flavonoid compounds. This is the first demonstration of anti-PC activity of flavonoid compounds.

Improvement in production and quality of gellan gum by Sphingomonas paucimobilis under high dissolved oxygen tension levels.

The effect of agitation rate and dissolved oxygen tension (DOT) on growth and gellan production by Sphingomonas paucimobilis was studied. Higher cell growth of 5.4 g l(-1) was obtained at 700 rpm but maximum gellan (15 g l(-1)) was produced at 500 rpm. DOT levels above 20% had no effect on cell growth but gellan yield was increased to 23 g l(-1 )with increase in DOT level to 100%. Higher DOT levels improved the viscosity and molecular weight of the polymer with change in acetate and glycerate content of the polymer.