Research Progress in Determination Methods of Formaldehyde Content in Indoor Air

The detection methods of formaldehyde content in indoor air, including traditional laboratory detection methods (AHMT spectrophotometry, phenol reagent spectrophotometry, acetyl acetone spectrophotometry and gas chromatography) and rapid detection methods (electrochemical sensor method, photoelectric spectrophotometry, etc.), were introduced and described. This paper systematically analyzes and compares the detection principle, applicable environment medium, detection flux and the advantages and disadvantages of each detection method. The future detection methods of formaldehyde content in indoor air were prospected.

Response of a Freshwater Fish Exposed to a Single Dose of Biofertilizer

The study was carried out to observe the effect of this biofertilizer (MOC) on the Body Muscle Protein (BMP) of Channa punctatus having average length 15.26±0.52cm and weight 28.85±5.028gm. At sub lethal concentration (0.42g.l -1 ), fishes were exposed for prolonged period and muscle protein was measured on 0, 7 th , 14 th , 21 th and 28 th days respectively. Five fishes were sacrificed after each day of exposure to estimate the amount of protein concentration in the muscle following Folin-phenol reagent method. A significant (p<0.05) increase in BMP was observed with the advance of days treatment. After an initial fall, the rise in the BMP concentration, indicating the experimental fish were suffered initially and ultimately victorious and able to increase the protein level in their body.

AN EXPERIMENTAL DESIGN APPROACH FOR OPTIMIZATION OF MODIFIED COLORIMETRIC FIRST-ORDER DERIVATIVE METHOD FOR ESTIMATION OF SERRALYSIN IN BULK AND PHARMACEUTICAL FORMULATION

Objective: The aim of the present work is to use experimental design to screen and optimize experimental variables for developing a colorimetric first-order derivative method for determining content of serralysin (SER) using biuret and Folin–Ciocalteu phenol reagent for stable color development. The method is based on the reaction of peptide bond in the protein with Biuret reagent in alkaline medium and further reaction of remaining tryptophan and tyrosine residues with Folin–Ciocalteu Phenol reagent to form a stable blue-colored complex (first-order derivative λmax 620 nm).Materials and Methods: A two-level full factorial design was utilized to screen the effect of Volume of NaOH (A), volume of biuret reagent (B), volume of Folin–Ciocalteu phenol reagent (C), and concentration of NaOH (D) on the formation of blue-colored SER - reagent complex (response - absorbance). A box Behnken experimental design with response surface methodology was then utilized to evaluate the main interaction and quadratic effects of these factors on the selected response.Results: With the help of a response surface plot and contour plot, the optimum values of the selected factors were determined and used for further experiments. These values were volume of NaOH (A) of 1.0 mL, volume of biuret reagent (B) of 0.25 mL, and volume of Folin–Ciocalteu phenol reagent (C) of 10 μL. The proposed method was validated according to the ICH Q2(R1) method validation guidelines. The developed colorimetric first-order derivative method was found to be simple, accurate, rapid, sensitive, precise, and economic. Further optimization of the method with experimental design approach makes it convenient for use in laboratory.Conclusion: The results of present study have clearly shown that an experimental design approach may be effectively applied to the optimization of a modified visible spectrophotometric method for estimation of SER in bulk and in pharmaceutical formulation with the least number of experimental runs possible. The method can be employed successfully for the estimation of SER in both bulk and tablet dosage form.

ANALISIS TOTAL FENOL PADA BERBAGAI FORMULASI REBUSAN KULIT SALAK BALI SIBETAN KARANGASEM SEBAGAI MINUMAN FUNGSIONAL

Background: Snakefruit’s bark that only so far as waste, can be processed into a functional beverage is good for health. Snakefruit’s bark contains phenolic compounds which are natural antioxidants in fruits. Objective: The purpose of this study is to determine the total phenol levels and sensory value of stew salak bali sibetan karangasem’s bark in various formulations as functional beverage. Methods: Analysis of total used spectrophotometric method with Folin-Ciocalteu phenol reagent and gallic acid standard. It also performed the water content analysis used thermogravimetry method. Result: Salak Bali Sibetan’s bark have average water content 24.1872±0.036%wb. The results of total phenol analysis showed that 2, 10, 20, 30, 40 gram of Salak Bali’s bark with 200 ml water are: 10,84±0,587; 13,79±0,756; 12,19±0,205; 12,02±0,268; 10,57±0,389 mg/L GAE respectirely. Conclusions: The highest total phenol content is (10g/200ml) formulation, and also supported by a sensory test showed that a majority of panelist also prefer that formulation because has good colour, flavor and smell. Keywords : Salak Bali’s Sibetan bark, total phenol, Folin-Ciocalteu.

Antiradical activity and amount of phenolic compounds in extracts obtained from some plant raw materials containing methylxanthine alkaloids

Summary Raw materials containing methylxanthine alkaloids such as yerba mate, guaraná, white and green tea, coffee seeds, chocolate and cacao seed powder and extracts obtained from these raw materials were investigated for their antioxidant features and the amount of phenolic compounds. The level of phenolic compounds was measured with the colorimetric method using Folin-Ciocalteu’s phenol reagent and antioxidant features was determined with the use of DPPH (2,2-diphenyl-1-picrylhydrazyl radical). Amounts of phenolic compounds were presented in percentages per mass of extracts and mass of raw materials. Antiradical potential was shown as the number of TAUDPPH units per mg of extracts and g of raw materials. The highest number of antiradical units TAUDPPH as well as the amount of phenolic compounds was calculated for white tea and its extracts and lowest for chocolate. The correlation coefficient between the content of phenolics and antiradical features of raw materials is equal to r=0.994.