PRE-TREATMENT TEMPERATURE AND MULTI-RESPONSE SURFACE OPTIMISATION OF ULTRASOUND-ASSISTED EXTRACTION OF ANTIOXIDANTS FROM RED DATES

Ziziphus jujube known as red dates are natural flora, are a rich source of antioxidant bioactive compounds and are widely used in making Chinese traditional medicine. However, the optimization of extraction conditions and demonstration of extraction kinetics of red dates remains a gap. Therefore, the main objective of this research was to enhance the antioxidant activity via DPPH, crude extract yield, and TPC by response surface methodology (RSM). Also, mathematical modeling of the TPC extraction kinetics was performed. Single-factor experiments were adopted to identify the preliminary RSM ranges of four extraction parameters such as liquid-solid ratio (10, 20, and 30 ml/g), extraction temperature (50, 60 and 70°C), time (40, 50 and 60min), and ultrasonic power (70, 80 and 90%). The extraction kinetics based on RSM optimized conditions were modeled into six extraction kinetic models. As result, the highest crude extract yield (4.56 g), highest TPC (0.023 g GAE/g extract), and highest antioxidant activity (85.88%) were obtained at 60ºC. The optimum values were liquid-solid ratio 30ml/g, extraction temperature 60°C, time 60 min, and ultrasonic power 70%. The antioxidant activity of red dates after optimization (90.59%) was higher than that of synthetic antioxidants, Butylated Hydroxytoluene (84.71%), and Butylated Hydroxyanisole (77.73%). Furthermore, the best-fitted kinetic model was the second-order kinetic model due to its coefficient of determination (R2) at 0.9849, being the closest to 1 and its root mean square error (RMSE) was the lowest, 0.001028 among other models

Isolation, structure elucidation, identification and quantitative analysis of di(2-ethylhexyl) phthalate (DEHP) from the roots of Chlorophytum boriviliuanum (safed musli)

Chlorophytum borivilianum (safed musli) is a traditional herbaceous medicinal plant belonging to family Liliaceae. Its roots are being employed in folk medicine. The crude extract of C. borivilianum has been consumed due to its versatile therapeutic uses. The scientific studies related to the important pharmacological properties are widely conducted and the remarkable bioactivities of C. borivilianum are proven in literatures. So far, the isolated chemical compounds are mainly saponins. In this research, the isolation was focused on compounds other than saponins and bis(2-ethylhexyl) benzene-1,2-dicarboxylate was isolated for the first time from the roots of C. borivilianum. The structure was identified based on the spectral data of 1H NMR, 13C NMR, DEPT, COSY, HMBC, HMQC and also based on the comparison with the previous literature data. This is the first report regarding the presence of this compound in C. borivilianum as well as its genus. A high performance liquid chromatographic (HPLC) method with photodiode array detection was established to identify and quantify bis(2-ethylhexyl) benzene-1,2-dicarboxylate

PID tuning with input constraint: application on food processing

PID controllers are probably the most common used industrial controller. PID controller has gone through few decades and has survived successfully through the changes of technology from analogue era into digital era. Actuator saturation is among the most common and significant problem in control systems design as it may lead to instability and consequently affect the performance of the process. Normal PID controller does not take this into consideration. Normally, an anti windup compensator is added as the remedy for this constraint. For alternative, this research investigates the possibility to tune PI controller when the system is under saturation. This research will put emphasis on first order plus time delay process and an expression is developed for saturation level, U as a function of controller gain, c K with the range of R 0.8-2 (ratio of time delay to time constant). Simple and accurate correlations are obtained for the saturation level (u) and controller gain, Kc. The proposed relations overcome this input constraint by explicitly considering the saturation level during the tuning of PI controller. Thus, saturation can be avoided and at the same time, it gives satisfactory performance. This method is named as BL tuning method and applied on spray drying process. The results showed that this BL tuning method could give satisfactory performance in controlling the process

Design of PI controller with input constraint: application on blending process

Because of their simplicity, reliability and effectiveness, proportional–integral–derivative (PID) controllers remain the most widely used controllers in the process industries. Actuator saturation is among the most common and significant problem in control systems design. Normal PID controller does not take this into consideration. Normally, an anti‐windup compensator is employed in the system to overcome the problem. In this contribution, a new set of controller tuning relations is developed to tune the PI controller when the system is under saturation. The blending process was described as first order plus time delay (FOPTD) process and an expression is developed for saturation level, U as a function of controller gain, Kc with the range of R 0.4–2 (ratio of time delay to time constant). The proposed tuning rule relate the parameters of the controller to the parameters of a FOPTD model of the plant to a step change in the set point. The proposed method was applied to PI controller and tested on the process of blending system of sweetened condensed milk. The performance of the controller with various tuning formulae incorporated with classical anti‐windup strategies has been compared. The simulation results showed that the proposed method could give satisfactory performance in controlling the process

Isolation, structure elucidation, identification and quantitative analysis of 1’-acetoxychavicol (ACA) from the roots of chlorophytum boriviliuanum (safed musli)

Chlorophytum borivilianum (safed musli) is a medicinally important plant. Its roots are being employed in folk medicine. Presently, the crude extract of C. borivilianum has been consumed for the treatment such as anti-diabetic, antiaging, anti-oxidant, anti-ulcer and anti-inflammatory and previous studies have been carried out to further confirm these remarkable bioactivities of C. borivilianum. In this research, 1’-acetoxychavicol acetate (ACA) was isolated from the roots of C. borivilianum. The structure of ACA was elucidated based on the spectral data of 1H NMR, 13C NMR, DEPT, COSY, HMBC, HMQC and also based on the comparison with the previous literature data. ACA was isolated in an isocratic elution that eluted with hexane and ethyl acetate in the ratio of 10:0.25. In the HPLC analysis, the separation of the crude methanol extract was completed within 20 min and the retention time of ACA in the sample was 7.31 min. The regression equation of the calibration curve was developed and the correlation coefficient was found to be 0.991. This is the first report regarding the presence of ACA in C. borivilianum as well as its genus. For the first time, a high performance liquid chromatographic (HPLC) method with photodiode array detection was developed for the quantitative determination and identification of ACA

Isolation, structure elucidation, identification and quantitative analysis of 1'-acetoxychavicol (ACA) from the roots of Chlorophytum boriviliuanum (safed musli)

Chlorophytum borivilianum (safed musli) is a medicinally important plant. Its roots are being employed in folk medicine. Presently, the crude extract of C. borivilianum has been consumed for the treatment such as anti-diabetic, anti-aging, anti-oxidant, anti-ulcer and anti-inflammatory and previous studies have been carried out to further confirm these remarkable bioactivities of C. borivilianum. In this research, 1’-acetoxychavicol acetate (ACA) was isolated from the roots of C. borivilianum. The structure of ACA was elucidated based on the spectral data of 1H NMR, 13C NMR, DEPT, COSY, HMBC, HMQC and also based on the comparison with the previous literature data. ACA was isolated in an isocratic elution that eluted with hexane and ethyl acetate in the ratio of 10:0.25. In the HPLC analysis, the separation of the crude methanol extract was completed within 20 min and the retention time of ACA in the sample was 7.31 min. The regression equation of the calibration curve was developed and the correlation coefficient was found to be 0.991. This is the first report regarding the presence of ACA in C. borivilianum as well as its genus. For the first time, a high performance liquid chromatographic (HPLC) method with photodiode array detection was developed for the quantitative determination and identification of ACA

Association of maternal Vitamin D status with glucose tolerance and caesarean section in a multi-ethnic Asian cohort: the growing up in Singapore towards healthy outcomes study

10.1371/journal.pone.0142239PLoS ONE10111-16GUSTO (Growing up towards Healthy Outcomes

Discovery of Q203, a potent clinical candidate for the treatment of tuberculosis

New therapeutic strategies are needed to combat the tuberculosis pandemic and the spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) forms of the disease, which remain a serious public health challenge worldwide1, 2. The most urgent clinical need is to discover potent agents capable of reducing the duration of MDR and XDR tuberculosis therapy with a success rate comparable to that of current therapies for drug-susceptible tuberculosis. The last decade has seen the discovery of new agent classes for the management of tuberculosis3, 4, 5, several of which are currently in clinical trials6, 7, 8. However, given the high attrition rate of drug candidates during clinical development and the emergence of drug resistance, the discovery of additional clinical candidates is clearly needed. Here, we report on a promising class of imidazopyridine amide (IPA) compounds that block Mycobacterium tuberculosis growth by targeting the respiratory cytochrome bc1 complex. The optimized IPA compound Q203 inhibited the growth of MDR and XDR M. tuberculosis clinical isolates in culture broth medium in the low nanomolar range and was efficacious in a mouse model of tuberculosis at a dose less than 1 mg per kg body weight, which highlights the potency of this compound. In addition, Q203 displays pharmacokinetic and safety profiles compatible with once-daily dosing. Together, our data indicate that Q203 is a promising new clinical candidate for the treatment of tuberculosis

Extraction and identification of di(2-ethylhexyl) phthalate from safed musli (chlorophytum borivilianum L.)

Chlorophytum borivilianum (safed musli) is a medicinally important plant. Its roots are being employed in folk medicine. Presently, the crude extract of C. borivilianum has been consumed for the treatment such as anti-diabetic, anti-aging, anti-oxidant, anti-ulcer and anti-inflammatory. Studies have been carried out to further confirm these remarkable bioactivities of C. borivilianum. So far, the isolated chemical constituents are mainly saponins. A fructo-oligosaccharide, three fatty acids, one sterol stigmasterol, hecogenin also have been reported to be isolated from the roots of C. borivilianum. In this research,di(2-ethylhexyl) phthalate (DEHP) was extracted from the aqueous extract of the roots of C. borivilianum. The yield of DEHP was found to be 33.70 mg, which was equivalent to 0.013% with reference to the total weight of root powder (250 g). The structure of DEHP was elucidated based on the spectral data of 1H-NMR, 13C-NMR, distortionless enhancement by polarization transfer (DEPT), correlation spectroscopy (COSY),heteronuclear multiple bond correlation (HMBC) and heteronuclear multiple quantum correlation (HMQC) and also based on the comparison with the previous literature data. This is the first report so far of occurrence and detail spectroscopic description of DEHP from C. borivilianum. Single experimental design and response surface methodology (RSM) was implemented to optimize the extraction conditions for obtaining the maximum yield of DEHP from the roots of C. borivilianum. DEHP was optimized because it could be a starting point to pave a way to isolate and quantify other pure compounds (minor or rare) from this herbaceous plant in order to use it as a tool for quality control and also for the future development of other therapeutic applications. Furthermore, DEHP was reported to possess some remarkable biological activities such as anti-leukemic, anti-microbial, anti-fungal, anti-tumour and antiviral activity against H1N1 disease. In this study, ultrasound-assisted extraction was applied for the effective extraction of DEHP and DEHP was quantified by high performance liquid chromatography (HPLC) analysis. Herein, three independent variables (extraction time, solid to solvent ratio and extraction temperature) with a five level design were evaluated using the central composite design (CCD), with the yield of DEHP as the response variable. Second-order polynomial model was found to be satisfactory in describing the experimental data for the total DEHP content. The analysis of variance (ANOVA) indicated that the main effect of solid to solvent ratio and the extraction temperature as well as the quadratic effects of all independent variables had significant effect ("Prob>F"<0.05) on the extraction yield of DEHP. The optimal extraction conditions were established as follow: extraction time of 92 min, solvent to solvent ratio of 1:38 (g/mL) and extraction temperature of 51°C. Using these adjusted optimal conditions, the predicted yield of DEHP by model was 0.44 ppm whereas the actual yield of DEHP was 0.43±0.01 ppm which was in close conformity with the predicted values as the relative error was just 2.72%. The extraction kinetic was studied using equilibrium extraction model (EEM) and diffusion extraction model (DEM). The kinetics results revealed EEM model was more suitable in describing the extraction process and the ethanol extraction of the roots of C. borivilianum achieved equilibrium within 70 minutes. Lastly, DEHP extracted from the roots C. borivilianum was tested for its anti-inflammatory activity. However, DEHP had shown a low inhibition effect on the anti-inflammatory activity in HYA assay with a percentage of inhibition of 4.02±1.17%. This study implied that DEHP was not active to inhibit the hyaluronidase enzyme and this indicated that the other compounds in the roots of C. borivilianum might contribute to the antiinflammatory activity as the previous researchers had obtained significant antiinflammatory activity from this plant