Development of Cyclobutene‐ and Cyclobutane‐Functionalized Fatty Acids with Inhibitory Activity against Mycobacterium tuberculosis

Eleven fatty acid analogues incorporating four‐membered carbocycles (cyclobutenes, cyclobutanes, cyclobutanones, and cyclobutanols) were investigated for the ability to inhibit the growth of Mycobacterium smegmatis (Msm) and Mycobacterium tuberculosis (Mtb). A number of the analogues displayed inhibitory activity against both mycobacterial species in minimal media. Several of the molecules displayed potent levels of inhibition against Mtb, with MIC values equal to or below those observed with the anti‐tuberculosis drugs D ‐cycloserine and isoniazid. In contrast, two of the analogues that display the greatest activity against Mtb failed to inhibit E. coli growth under either set of conditions. Thus, the active molecules identified herein may provide the basis for the development of anti‐mycobacterial agents against Mtb.     

Encapsulation of mangosteen pericarp anthocyanin-rich extract by spray drying

Mangosteen pericarp anthocyanin-rich extract (MPA) was encapsulated by maltodextrin dextrose equivalent 20 (MD20) combined with gum arabic (GA), inulin (IN) or pectin (PEC) using spray drying. The highest encapsulation efficiency and anthocyanin content exhibited MD20:PEC and MD20:IN combinations. The MPA-encapsulated powders had a crystalline-mixed amorphous structure. Scanning electron microscopy (SEM) analysis showed smooth, round, fine particles. Fourier transform infrared spectroscopy (FTIR) analysis confirmed entrapment of anthocyanins by carrier agents. Thermogravimetric analysis (TGA) revealed a high thermal stability of encapsulated powders at temperatures <200°C and found that encapsulation reduced thermal degradation of anthocyanins. Incorporation of MPA-encapsulated powders into natural yoghurt produced shelf-stable naturally coloured product but slightly suppressed the multiplication of Lactobacillus bulgaricus. Encapsulation of anthocyanin-rich mangosteen pericarp extract using spray drying presents a viable opportunity for food technologists to utilise this source in the development of functional food products.     

Application of gas anti-solvent process to the recovery of andrographolide from <Emphasis Type="Italic">Andrographis paniculatanees</Emphasis>

The gas anti-solvent (GAS) process was employed to extract andrographolide, which is the active ingredient found in Andrographis Paniculatanees, using carbon dioxide as an anti-solvent. The effects of temperature, flow rate and solvent type on the extraction recovery, particle size and morphology were investigated in this study. The experiments were conducted at the temperature ranging from 25–45 °C, carbon dioxide flow rate of 1–15 mL/min, and various types of organic solvents (methanol, ethanol, acetone and N,N-dimethylformamide). The extracted product was analyzed using high performance liquid chromatography (HPLC). The highest extraction yield was found to be 1.24 g andrographolide per 100 g of A. paniculata when using acetone as a solvent, carbon dioxide flow rate of 5 mL/min and the temperature of 35 °C. It was also found that no significant change in size or morphology of the precipitates was observed when changing temperature, carbon dioxide flow rate and solvents.     

Removal of heavy metal ions by iron oxide coated sewage sludge

The municipal sewage sludge was modified with iron oxide employed in metal ions removal. The surface modification method was proposed and the effect of parameters in the preparation was studied. The iron oxide coated sludge had higher surface area, pore volume and iron content, compared to uncoated sludge. The suitable conditions for removal of Cu(II), Cd(II), Ni(II) and Pb(II) ions from solutions were investigated using batch method. The suitable pH value in the extraction was 7 for adsorption of Cd(II) and Ni(II), 6 for Cu(II) and 5 for Pb(II) ions. The presence of NaNO(3), Ca(NO(3))(2) and Na(2)SO(4) in metal solution in the concentration of 0.01 M and 0.50 M could reduce the removal efficiency. The adsorption isotherms for the adsorption of the metal ions were defined by Langmuir relation. The maximum adsorption capacity of the iron oxide coated sludge for Cu(II), Cd(II), Ni(II) and Pb(II) was 17.3, 14.7, 7.8 and 42.4 mg g(-1), respectively. The adsorption kinetics for every metal ions followed pseudo-second order model. The metal removal from wastewater by iron oxide coated sludge was also demonstrated.