Detection of virulent Newcastle disease virus using a phage-capturing dot blot assay

Newcastle disease virus (NDV) strains can be classified as virulent or avirulent based upon the severity of the disease. Differentiation of the virus into virulent and avirulent is necessary for effective control of the disease. Biopanning experiments were performed using a disulfide constrained phage displayed heptapeptide library against three pathotypes of NDV strains: velogenic (highly virulent), mesogenic (moderately virulent) and lentogenic (avirulent). A phage clone bearing the peptide sequence SWGEYDM capable of distinguishing virulent from avirulent NDV strains was isolated. This phage clone was employed as a diagnostic reagent in a dot blot assay and it successfully detected only virulent NDV strains

Probiotic growth pattern and physicochemical evaluation of water kefir fermentation

Probiotics are live-friendly microorganisms that can confer a health benefit on the host if it is consumed in sufficient amounts. Water kefir is a probiotic-rich fermented beverage that contains multi-species of live cultures. Brown sugar and palm sugar were used for water kefir fermentation due to their high sucrose and mineral contents. The objective of this study was to determine the probiotic growth pattern of water kefir and to evaluate the physicochemical parameters, including the pH changes, lactic acid content, reducing sugar content, and total soluble solids. The fermented water kefir was collected at every 6-hour interval, until the end of 72 hours of fermentation. The growth curve was determined by enumerated probiotics on De Man, Rogosa, and Sharpe (MRS) agar, Yeast ExtractPeptone-Dextrose (YPD) agar, and Gluconobacter (GM) agar plates, respectively. MRS, YPD, and GM agar plates were used to enumerate lactic acid bacteria, yeast, and acetic acid bacteria, respectively. The result showed increased probiotic growth as fermentation time increased with different phases observed from the growth curve. The stationary phase of probiotics was recorded at 30-42 h and was recommended as the optimal harvesting point. Besides, longer fermentation time produced lower pH values and lower total soluble solids while higher lactic acid and higher reducing sugars. At the end of fermentation, the concentration of lactic acid and reducing sugars were 2.16 ± 0.09 g/L and 13.66 ± 0.14 mg/mL, respectively. In conclusion, probiotics from water kefir fermentation are suggested to be best harvested between 30-42 hours and can be used for self-consume or downstream processing

Polycaprolactone/cellulose acetate loaded psidium guajava essential oil electrospun nanofibrous mat dressing for healing wounds

Natural products and essential oils of medicinal plants are extensively employed in wound healing, particularly in the pharmaceutical industry. Essential oils obtained from Psidium guajava were utilised as an antibacterial agent against Bacillus subtilis, Staphylococcus aureus, and Enterococcus faecalis, and to control drug-resistant strains. In this study, electrospinning for applications in antimicrobial activity and drug delivery systems was used to develop biocomposite nanofibers of Polycaprolactone (PCL)/Cellulose Acetate (CA) and Psidium guajava essential oil (PGEO). Images from the FESEM revealed that the mean fire diameters were 120 nm for the PCL/CA and 223 nm for PCL/CA/PGEO biocomposite nanofibers. The diameters of the nanofibers were increased following the addition of PGEO into PCL/CA nanofibers. Furthermore, FTIR studies revealed the -OH peak in pure electrospun PCL/CA and PCL/CA/PGEO, lacking pure PGEO nanofibrous mats. These findings reflect that Psidium guajava essential oil/PCL/CA electrospun nanofibers are promising candidates for presenting bioactive compounds in wound management or other approaches for wound healing and bacterial infections

Real-time cytotoxicity assay of water extracts Hibiscus rosa-sinensis

A real-time impedance-based electrochemistry assay was used for assessing the cytotoxicity effect of water extract Hibiscus Rosa-Sinensis on Vero cell line. In this study, H. rosa-sinensis was extracted by using the water extraction with three different concentration which were 200, 100 and 50 µg/mL. The phytochemical compounds in the extract were analyzed by using the Gas Chromatography-Mass Spectrometry (GC-MS). The GC-MS result showed that the extract contains bioactive compounds such as n-hexadecanoic acid, pentadecanoic acid, phenol, 2,4-bis(1,1- dimethylethyl) and octadecanoic acid that have bioactive properties such as cytotoxic and antioxidant. The cytotoxic effect of the extract on normal cell line was assessed by using Real-Time Cell Analysis (RTCA) instrument. The result showed that there was no significant cytotoxicity effect against Vero cell lines. This result showed that the real-time impedance-based assay can be utilized to monitor changes of the cells and to determine the inhibitory concentration of the extract

Microbiological and physicochemical evaluation on the fermentation of water kefir using brown sugar and palm sugar

Probiotics are live microorganisms which when administered in sufficient amounts confer a health benefit on the host. They are gaining increasing interest from the public due to their health benefits. Probiotics can be administered as food supplements or food ingredients. Particularly, the fermented beverage is a popular vehicle to deliver probiotics. Therefore, present work aimed to develop a non-dairy probiotic water kefir beverage using brown sugar and palm sugar that is suitable to be consumed by vegans and consumers with lactose intolerance and milk allergies. Brown sugar and palm sugar were prepared as the substrate for kefir grains, in the ratio of 2:1, which were 50 g/L and 25 g /L respectively. The fermentation process was carried out for 72 hours. The fermented water kefir was collected every 6 hours interval to evaluate the microbiological and physicochemical characteristics of the water kefir. The result indicated that the longer fermentation time produced lower pH values, higher lactic acid, higher reducing sugars, and lower total soluble solids. In conclusion, the ideal fermentation time to produce water kefir using brown sugar and palm sugar was 48 hours, with greater amount of lactic acid bacteria (6.43 ×106 CFU/mL), yeasts (7.23 ×106 CFU/mL), and acetic acid bacteria count (8.07 ×106 CFU/mL)

Phytochemical analysis and GC-MS profiling in the flower of Plumeria alba

Therapeutic properties of the medicinal plant are due to the presence of phytochemical constituents. The phytochemical constituents of Plumeria alba flower were investigated by phytochemical screening assays and gas chromatography-mass spectrometry (GC-MS). The phytochemical screening of hexane, dichloromethane, ethyl acetate, butanol, and aqueous extracts of P. alba flower showed it contains a various concentration of saponins, flavonoids, tannins, steroids, volatile oil and phenolic compounds. Several major chemical constituents that were identified is squalene, bis(2-ethylhexyl) phthalate, methyl (methyl 4-O-methyl-α-d-mannopyranoside) uronate and tricyclo [7.2.0.0(2,6)] undecan-5-ol, 2,6,10,10-tetramethyl- (isomer 2) by using GC-MS technique

The use of diffuse optical spectroscopy and diffuse correlation spectroscopy system for monitoring of tumor response to photodynamic therapy

Photodynamic therapy (PDT) of cancer works via direct cytotoxicity, causing damage to tumor vasculature and stimulating the body’s anti-tumor immune response. PDT outcome depends on the parameters used; therefore an in vivo tumor response monitoring system is useful for optimization of the treatment protocol. The combined use of diffuse optical spectroscopy and diffuse correlation spectroscopy allows us to measure the tissue oxygen saturation (StO2) and relative blood flow (rBF) in tumors. These parameters were measured before and after PDT in mouse tumor models and were calculated as ratios relative to the baseline in each tumor (rStO2 and rBF). Readings were also measured in drugonly control tumors. In responders (mice with tumor eradication), significant PDT-induced decreases in both rStO2 and rBF levels were observed at 3h post-PDT. The rStO2 and rBF readings in these mice remained low until 48h post-PDT, with recovery of these parameters to baseline values observed 2 weeks after PDT. In non-responders (mice with partial or no response), the rStO2 and rBF levels decreased less sharply at 3h post-PDT, and the rBF values returned toward baseline values at 48h post-PDT. By comparison, the rStO2 and rBF readings in drug-only control tumors showed only fluctuations about the baseline values. Thus tumor response can be predicted as early as 3h post-PDT. Recovery or sustained decreases in rStO2 and rBF up till 48h post-PDT were correlated to long-term tumor control. Diffuse optical measurements can thus facilitate early assessment of tumor response to PDT to aid in treatment planning.Published versio

Hemodynamic monitoring of Chlorin e6-mediated photodynamic therapy using diffuse optical measurements

Tumor response during photodynamic therapy (PDT) is heavily dependent on treatment parameters such as light dose, photosensitizer concentration, and tissue oxygenation. Therefore, it is desirable to have a real-time hemodynamic monitoring device in order to fine-tune the parameters and improve PDT efficacy. In this paper, such a tumor response monitoring system was built incorporating both frequency domain diffuse optical spectroscopy (FD-DOS) and diffuse correlation spectroscopy (DCS), which enables concurrent monitoring of tissue oxygenation (StO2), total hemoglobin concentration (THC) and relative blood flow (rBF). The tumor metabolic rate of oxygen (TMRO2) was calculated by using the hemodynamic parameters. Mouse models bearing xenograft tumors were subjected to chlorin e6 (Ce6)-mediated PDT, and the four parameters were monitored with varying treatment conditions. The results show (1) At 3 h post-PDT, rStO2, rBF and rTMRO2 exhibited sharp PDT-induced decreases in responders (>40% reduction in tumor volume). Statistically significant difference between responders and non-responders were observed in rStO2 and rBF, but not in rTMRO2. (2) Non-responders show gradual recovery of rStO2, rBF and rTMRO 2 from ∼24 h post-PDT, while responder group did not show recovery up until 48 h post-PDT. Long-term study results up to 2 weeks are also shown. It suggests the hybrid diffuse optical system is not only capable of real-time treatment monitoring, but also able to extract tumor metabolic rate of oxygen to provide more insights about therapy mechanism. Translation of this technique to the clinic will make a quick prognosis feasible and help with treatment optimization. © 2014 Elsevier B.V. All rights reserved.1

Real-time cytotoxicity assay of water extracts Hibiscus rosa-sinensis

A real-time impedance-based electrochemistry assay was used for assessing the cytotoxicity effect of water extract Hibiscus Rosa-Sinensis on Vero cell line. In this study, H. rosa-sinensis was extracted by using the water extraction with three different concentration which were 200, 100 and 50 µg/mL. The phytochemical compounds in the extract were analyzed by using the Gas Chromatography-Mass Spectrometry (GC-MS). The GC-MS result showed that the extract contains bioactive compounds such as n-hexadecanoic acid, pentadecanoic acid, phenol, 2,4-bis(1,1-dimethylethyl) and octadecanoic acid that have bioactive properties such as cytotoxic and antioxidant. The cytotoxic effect of the extract on normal cell line was assessed by using Real-Time Cell Analysis (RTCA) instrument. The result showed that there was no significant cytotoxicity effect against Vero cell lines. This result showed that the real-time impedance-based assay can be utilized to monitor changes of the cells and to determine the inhibitory concentration of the extract