Color Doppler ultrasound in high-low risk pregnancies and its relationship to fetal outcomes: a cross-sectional study.

Objective: To calculate the multivessel color Doppler indices in high-risk and low-risk pregnancies and relate these to fetal outcomes. Methods: The investigation involved 60 patients who were pregnant. The patients were separated into groups according to assessment of low and high risk. The patients underwent color Doppler ultrasonography to detect the maternal and fetal blood vessels, and the measured Doppler indices were then analyzed for any association with fetal outcomes. Results: The gestational stages (in weeks) of the participants at the respective times of investigation and delivery were 32.06 ± 2.98 and 36.2 ± 1.78 in the low-risk group and 29.21 ± 1.95 and 29.83 ± 1.86 in the high-risk group. The pulsatility index (PI), resistive index (RI), and systolic/diastolic ratio (SD) decreased with gestation length in the low-risk group, whereas in the high-risk group, these values increased in the uterine and umbilical arteries. With increased gestational stage, MCA-PSV (peak systolic velocity) in the middle cerebral artery (MCA) increased, while PI decreased. Pulsatile and reversal flow of the uterine vein, the vein of Galen, and the umbilical vein were noted in high-risk pregnancies, and these negatively affected the fetal outcome. The fetal venous parameters were more specific and sensitive for predicting an unfavorable fetal outcome than the arterial factors, with a greater negative predictive value. Conclusion: The results of our study indicate that abnormal Doppler indices of the blood vessels in high-risk pregnant patients will result in adverse clinical outcomes. Therefore, the patients can be monitored and managed accordingly using Doppler ultrasonography.

Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants.

BACKGROUND: Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed. RESULTS: Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained. CONCLUSIONS: The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.

Statistical approach to study the interactive effects of process parameters for enhanced xylitol production by Candida tropicalis and its potential for the synthesis of xylitol monoesters.

Previous results showed that an indigenously isolated yeast strain of Candida tropicalis was found to produce 12.11 g/L of xylitol under unoptimized conditions in presence of 50 g/L of xylose. In the present study, optimizing the process using one-variable at-a-time resulted in the production of 59.07 g/L of xylitol in 96 h in presence of 100 g/L xylose. Further optimization using response surface methodology led to the production of 65.45 g/L in medium containing 100 g/L xylose, 0.5% yeast extract, 0.03% MgSO(4).7H(2)O and 0.2% KH(2)PO(4), pH-4.5, 30 °C, 200 r/min for 96 h with 4% inoculum level. Addition of 1% methanol in response surface methodology optimized-medium led to the production of 67.12 g/L. Scaling up in 10 L fermentor resulted in productivity of 0.80 g/Lh with yield of 0.68 g/g. Efficient synthesis of xylitol esters was achieved with butyric acid (50.32%) and caproic acid (38.36%) in 4 h using Pseudomonas aeruginosa lipase in t-butanol: tetrahydrofuran (1:1 v/v).

Evaluation of corncob hemicellulosic hydrolysate for xylitol production by adapted strain of Candida tropicalis.

A maximum xylose extraction of 21.98 g/L was obtained in hydrolysate with a solid to liquid ratio of 1:8 (w/v) at 1% H(2)SO(4) and treated for 30 min. The optimized and treated corncob hemicellulosic hydrolysate medium supplemented with (g/L) yeast extract 5.0, KH(2)PO(4) 2.0, MgSO(4)·7H(2)O 0.3 and methanol 10 mL whose pH was adjusted to 4.5 acts as production medium. Under this condition; the adapted strain of C. tropicalis resulted in 1.22-fold increase in xylitol yield and 1.70-fold enhancement in volumetric productivity was obtained as compared to parent strain of C. tropicalis. On concentrating the hydrolysate under vacuum using rotavapor proves to be efficient in terms of improved xylitol yield and productivity over microwave assisted concentration using adapted strain of C. tropicalis. The immobilized cells of C. tropicalis resulted in more than 70% efficiency up to third cycle. The xylitol production could be scaled up to 10 L fermentor.

Fermentation behavior of an osmotolerant yeast D. hansenii for Xylitol production.

Realizing the importance of xylitol as a high-valued compound that serves as a sugar substitute, a new, one step thin layer chromatographic procedure for quick, reliable, and efficient determination of xylose and xylitol from their mixture was developed. Two hundred and twenty microorganisms from the laboratory stock cultures were screened for their ability to produce xylitol from D-xylose. Amongst these, an indigenous yeast isolate no.139 (SM-139) was selected and identified as Debaryomyces hansenii on the basis of morphological and biochemical characteristics and (26S) D1/D2 r DNA region sequencing. Debaryomyces hansenii produced 9.33 gL(-1) of xylitol in presence of 50.0 gL(-1) of xylose in 84 h at pH 5.5, 30°C, 200 rpm. In order to utilize even higher concentrations of xylose for maximum xylitol production, a xylose enrichment technique was developed. The strain of Debaryomyces hansenii was obtained through xylose enrichment technique in a statistically optimized medium containing 0.3% yeast extract, 0.2% peptone, 0.03% MgSO(4) .7H(2) O along with 1% methanol. The culture was inoculated with 6% inoculum and incubated at 30°C and 250 rpm. A yield of 0.6 gg(-1) was obtained with a xylitol volumetric productivity of 0.65 g/L h(-1) in the presence of 200 gL(-1) of xylose although up to 300 gL(-1) of xylose could be tolerated through batch fermentation. Through this technique, even higher concentrations of xylose as substrate could be potentially utilized for maximum xylitol production.

Examine growth inhibition pattern and lactic acid production in Streptococcus mutans using different concentrations of xylitol produced from Candida tropicalis by fermentation.

Twenty clinical isolates of Streptococcus sp. were isolated from six clinical samples of dental caries on MSFA. Amongst these isolates, five clinical isolates were identified as S treptococcus mutans on the basis of morphological, biochemical and 16S rDNA sequencing. The isolated strains of S. mutans were exposed to fermented and purified xylitol (0.25-15.0%) and tested for its anti-microbial effects against control medium (Brain Heart Infusion without xylitol) after 12 h. The plate assay was developed using bromocresol green as an indicator dye in order to study the relative growth inhibition pattern of clinical sample at different concentrations of an anti-microbial compound in a single petriplate. The morphology of S. mutans cells in brain heart infusion (BHI) medium containing xylitol resulted in a diffused cell wall as observed using gram staining technique. The minimum inhibitory concentration (MIC) is 0.25% for S. mutans obtained from different clinical samples. The MIC(50) and MIC(90) is 5.0% and 10.0% xylitol respectively of the selected S. mutans being designated as clinical isolate B (6). The zone of inhibition was 72 mm and lactic acid production was 0.010 g/l at 10% xylitol concentration in Brain Heart Infusion Broth.

Fermentation behavior of osmophilic yeast Candida tropicalis isolated from the nectar of Hibiscus rosa sinensis flowers for xylitol production.

Eighteen yeast species belonging to seven genera were isolated from ten samples of nectar from Hibiscus rosa sinensis and investigated for xylitol production using D-xylose as sole carbon source. Amongst these isolates, no. 10 was selected as the best xylitol producer and identified as Candida tropicalis on the basis of morphological, biochemical and 26S rDNA sequencing. C. tropicalis produced 12.11 gl(-1) of xylitol in presence of 50 gl(-1) of xylose in 72 h at pH 5, 30°C and 200 rpm. The strain of C. tropicalis obtained through xylose enrichment technique has resulted in a yield of 0.5 gg(-1) with a xylitol volumetric productivity of 1.07 gl(-1)h(-1) in the presence of 300 gl(-1) of xylose through batch fermentation. This organism has been reported for the first time from Hibiscus rosa sinensis flowers. Realizing, the importance of this high valued compound, as a sugar substitute, xylose enrichment technique was developed in order to utilize even higher concentrations of xylose as substrate for maximum xylitol production.

Bacillus sphaericus: the highest bacterial tannase producer with potential for gallic acid synthesis.

An indigenously isolated strain of Bacillus sphaericus was found to produce 1.21 IU/ml of tannase under unoptimized conditions. Optimizing the process one variable at a time resulted in the production of 7.6 IU/ml of tannase in 48 h in the presence of 1.5% tannic acid. A 9.26-fold increase in tannase production was achieved upon further optimization using response surface methodology (RSM), a statistical approach. This increase led to a production level of 11.2I U/ml in medium containing 2.0% tannic acid, 2.5% galactose, 0.25% ammonium chloride, and 0.1% MgSO(4) pH 6.0 incubated at 37°C and 100 rpm for 48 h with a 2.0% inoculum level. Scaling up tannase production in a 30-l bioreactor resulted in the production of 16.54 IU/ml after 36 h. Thus far, this tannase production is the highest reported in this bacterial strain. Partially purified tannase exhibited an optimum pH of 5.0 with activity in the pH range of 3 to 8; 50°C was the optimal temperature for activity. Efficient conversion of tannic acid to purified gallic acid (90.80%) was achieved through crystallization.

Characterization of cross-linked immobilized lipase from thermophilic mould Thermomyces lanuginosa using glutaraldehyde.

Cross-linked enzyme aggregates (CLEAs) have emerged as an interesting biocatalyst design for immobilization. Using this approach, a 1,3 regiospecific, alkaline and thermostable lipase from Thermomyces lanuginosa was immobilized. Efficient cross-linking was observed when ammonium sulphate was used as precipitant along with a two fold increase in activity in presence of SDS. The TEM and SEM microphotographs of the CLEAs formed reveal that the enzyme aggregates are larger in size as compared to the free lipase due to the cross-linking of enzyme aggregates with glutaraldehyde. The stability and reusability of the CLEA with respect to olive oil hydrolysis was evaluated. The CLEA showed more than 90% residual activity even after 10 cycles of repeated use.