Water droplet surface tension method - An innovation in quantifying saponin content in quinoa seed.

Quinoa surface borne saponins are bitter tasting anti-nutritional compounds that must be removed before consumption of the seed. To determine saponin content, the currently available standard afrosimetric foam test method only determines the presence of saponin via a rating of either 'acceptable' or 'unacceptable'. A water droplet surface tension (WDST) based innovative method was developed that can quantify saponin content in aqueous solutions with greater accuracy. The method comprised four steps: solution preparation, droplet creation, image capture and image analysis using Axisymmetric Drop Shape Analysis computer software. The method applied satisfactorily to saponin content up to 0.2 mg.ml-1 as higher concentrations did not further reduce the surface tension. Results demonstrated that saponin concentration may be measured in the range 0.05 to 0.15 mg.ml-1 (0.05 - 0.15% saponin by weight of seed). Validation of the WDST method on commercial and experimental samples offers quinoa processors an accurate inexpensive way of measuring saponin concentration to satisfy current seed quality specifications.

Evaluation of foaming potential for water treatment: limits and developments.

The critical issue generated by foaming in wastewater treatment plants (WWTPs) is a problem that is currently very common and shared, but which to date is treated mainly only at the management level. In this work, an experimental study with foam tests on real and synthetic waters was conducted using a laboratory scale plant and foaming power indices were calculated. To date, the estimation of foaming potential is mainly based on these indices which give information only on height/volume of foams but not on the type of foams, in terms of consistency and therefore stability. Tests showed that foaming power indices were highly variable with the same water: it was not possible to identify a single foaming potential value for each water. Two models were proposed to estimate the percentage increase in height of chemical foams produced following the introduction of air below the surface of a liquid. In terms of determination coefficient, the results obtained from the complex model were better: R2 was 0.82 for the simple linear model and 0.90 for the complex one. This approach has allowed to underline some critical aspects of foaming potential as it is determined today and the possible improvements applicable for a more objective evaluation.

Fast Identification of Cyathula officinalis and Its Adulterant and Doped Adulterant Based on Properties and Foam Test / 中国实验方剂学杂志

Objective: To rapidly identify Cyathula officinalis and its adulterant C. capitata and C. officinalis*C. capitata and doped adulterant. Method: Properties combined with foam test method were used for identifying C.officinalis, its adulterant and doped adulterant. In the aspect of properties,6 aspects including shape,size,texture,color,smell and taste,were observed, smelled and tasted. In the aspect of foam test,the volume of foam produced was used as the determination index to investigate the sample amount,water amount, shaking time,particle size,water temperature,repeatability,adulteration ratio and its stability. Result: In the aspect of properties,C. officinalis and its adulterant showed obvious difference in the shape,size,color,texture,smell and taste,especially the red color and bitter taste of its adulterant. In the aspect of foam test,the optimum parameters were as follows:sample particle (screened with 3 sieves) 0.3 g,a test tube with plug and scale,water 10 mL and airtight,forced shaking up and down for 1 min,settling for 5 min. Such method can be used to identify C. officinalis, its adulterant and doped adulterant. The volume of foams produced by C. officinalis and its adulterant and different ratio of doped adulterant showed no change within 5-30 min,slightly decreases after 9 h; the higher adulteration ratio; the larger volume of foam and better stability. The 8 batches of C. officinalis and 8 batch of adulterants proved that the volume of the foams produced was all less than 2 mL in the C. officinalis,more than 13 mL in the adulterant is,and more than 5 mL in 5% doped adulterant, showing statistical difference. From the properties combined with foam test,5 specific identification elements were obtained for identifying C. officinalis, its adulterant and doped adulterant. Conclusion: Through the 5 specific identification elements,the properties combined with foam test can be used to distinguish the C. officinalis from its adulterant C. officinalis and C. officinalis*C. capitata and doped adulterant,characterized by accuracy,simpleness,short time,low cost and feasibility. It can provide a new method and reference for identifying C.officinalis from its adulterant and doped adulterant.

Effect of chemical and biological surfactants on activated sludge of MBR system: microscopic analysis and foam test.

A bench-scale MBR unit was operated, under stressing condition, with the aim of stimulating the onset of foaming in the activated sludge. Possible synergies between synthetic surfactants in the wastewater and biological surfactants (Extra-Cellular Polymeric Substances, EPSs) were investigated by changing C/N ratio. The growth of filamentous bacteria was also discussed. The MBR unit provided satisfactory overall carbon removal overall efficiencies: in particular, synthetic surfactants were removed with efficiency higher than 90% and 95% for non-ionic and ionic surfactants, respectively. Lab investigation suggested also the importance to reduce synthetic surfactants presence entering into mixed liquor: otherwise, their presence can significantly worsen the natural foaming caused by biological surfactants (EPSs) produced by bacteria. Finally, a new analytic method based on "ink test" has been proposed as a useful tool to achieve a valuation of EPSs bound fraction.

Foam test on gastric aspirates in the prediction of respiratory distress syndrome

Philippine statistics show that 66 percent of babies are delivered outside the hospital. Thus, the need for a simple and rapid screening test done immediately after birth to identify those babies who will develop Respiratory Distress Syndrome (RDS) and may subsequently require referral to a tertiary care unit, is evident. Foam test was done on samples of amniotic fluid and gastic aspirate within one hour after collection on 61 deliveries, 35 term and 26 premature. Results of the foan test were correlated with the incidence of RDS. Of the 61 subjects, 39 gave a positive foan test, none of whom developed RDS. Six had an intermediate foam test, also none of whom developed RDS. Results of the foam test on gastric aspirate showed a parallelism with those done on amniotic fluid in 60 out of 61 subjects. Statistical analysis showed that the foam test has a 100 if positive. These data showed that the foam test on gastric aspirate has a high predictive accuracy in the assessment of fetal lung maturity.