M.Z. Borhan

Optimization of ball milling parameters to produce Centella asiatica herbal nanopowders

Nanopowders of Centella asiatica was produced using planetary ball mill by varying milling parameters such as milling time, mass concentration, and bead amount. Particle size analysis employing photon correlation spectroscopy was carried out to record the effect of milling parameters on the particle size produced. The morphology of milled powders was also analyzed using a field emission scanning electron microscope. The bioactive component, asiatic acid, was extracted from various sizes of C. asiatica powders, and its extraction yield at different powder size was calculated by high-performance liquid chromatography. Optimization of milling parameters was found to be a crucial step in determining the content of asiatic acid extracted. In this study, the highest amount of asiatic acid extracted was 25.4 mg/g, obtained at moderate conditions of the following milling parameters: 4 h of milling time, 1.2% (w/v) concentration of powder, and 25 g of bead load.

Green Extraction: Enhanced Extraction Yield of Asiatic Acid from Centella asiatica (L.) Nanopowders

Nanopowders of Centella asiatica (L.) were produced using planetary ball mill in order to investigate the differences of water extraction yield of asiatic acid as compared to micropowders of Centella asiatica. Effect of extraction time (20–60 min) on extraction yield of asiatic acid from Centella asiatica was examined. Results showed that water extraction of asiatic acid using Centella asiatica nanopowders exhibits was almost 50% higher extraction yield with 7.09 mg/g as compared to the micropowders of Centella asiatica. It was concluded that nanopowders contributed in enhancing water extraction yield of asiatic acid as compared to micropowders. Thereby utilizing nanopowders in water extraction could improve the extraction of asiatic acid via clean, eco-friendly, and less expensive process.

Effect of Milling Time on Particle Size and Surface Morphology of Commercial Zeolite by Planetary Ball Mill

Ball milling is a top down approach and a method to reduce size of particle while Zeolite is a valuable inorganic materials having wide variety of applications. In this paper, ball milling of commercial synthetic Zeolite powder was studied with their time varied. Wet ball milling was selected as a potential means to decrease the particle size of Zeolite over dry grinding. The parameters that included in this study were rotational speed, balls to powder ratio, water to powder ratio and milling time. These nanozeolite were characterized via Zeta-sizer nanoseries of particle sizer, FESEM, and also FTIR. Results showed that commercial synthetic Zeolite powder with particle size larger than 45 μm may be reduced into the size range between 0.2 0.3 μm by planetary ball mill.

Effect of Nanonization on Physicochemical Properties of Centella asiatica Powders

Centella asiatica (C. Asiatica) contains asiatic acid as one of bioactive constituent that has the commercial medicinal value such as anticancer and also possess wound healing property. The ball milling process was carried out at 0.5, 4 and 8 hours. The effects of ball milling at different times were characterized using particles size analysis (Photon Correlation Spectroscopy) and Fourier Transform infra red (FTIR) Spectroscopy. The surface morphology was characterized by Field-Emission Scanning Electron Microscope (FESEM). As a result, smallest particles size by mean 279.5 nm was produced at a longest milling time (8 hr) and FTIR spectra shows there is no obvious change in the structure of C. asiatica nanopowders as compared to the micropowders. Centella asiatica nanopowders shows good extraction yield of asiatic acid with 5.5 μg/ml of yield but poor inhibition of DPPH as compared to micropowders.

Effect of weight percentage on PTFE/nanoporous Zeolite composite

In this research, Zeolite will be selected as a potential material to combine with Polytetrafluoroethylene (PTFE) to form composite. Zeolite is a porous material with known as molecular sieve and aluminosilicate materials that have open structure of interconnected cavities that can be accessed by molecules, atoms and ions species. Besides, PTFE is a polymer of the type of Teflon and most widely used fluorocarbon polymer for engineering applications with a great combination of desirable chemical and physical properties likes excellent high temperature stability, chemical resistance, electric properties and also extremely low coefficient of friction. Experimental process will be included the conversion of Zeolite to nanoporous Zeolite by wet milling method. Then, this nanoporous Zeolite will mix together with PTFE by weight percentage to form a nanocomposite that gives high impact in properties. This composite will characterize via Field Emission Scanning Electron Microscopy (FESEM) and Thermo Gravimetric Analysis (TGA).

Impact of Nanopowders on Exraction Yield of Centella asiatica

Centella asiatica (C. Asiatica) is a traditional herb that has been used in raditional medicine especially in Asia region. Recently the pharmalogical study of Asiatic acid (AA) which is one of bioactive constituents in C. Asiatica has been studied and revealed that this compound has a potential to be use in medicine area. The objective of this paper is to produce nanoparticles C. Asiatica by Planetary Ball Mill (PBM) and determined the effect of nanonization on extraction yield of asiatic acid. The particles were analyzed using particle sizer to determine size of particle produce and the morphology was evaluated through FESEM. As a result, the mean particles size of nanopowders was 501.10 nm and the extraction of asiatic acid using nanopowders showed 82.09 % higher than original powder.

Production of Herbal Nanopowders: Effect of Milling Time

Several clinical studies have proved the triterpenes in this herb have therapeutic properties and posses significant to health such as antitumor and wound healing. Centella asiatica nanopowders (CANPs) have been produced via top down approach using Planetary Ball Mill (PBM) at 0.5, 4 and 8 hours of milling in optimized condition. CANPs have been characterized using Photo Correlation Spectroscopy (PCS), Field Emission Scanning Electron Microscope (FESEM) and High Performance Liquid Chromatography (HPLC). As a result significant reduction on size was observed as increased a milling time by comparing their z-Average (nm) and the morphology of CANPs exist in the agglomerated form. The HPLC results showed significant increase in concentration of asiatic acid by comparing the concentration of asiatic acid in extract of CANPs and coarse powders whereby the asiaticoside completely disappeared after milling. Thus, nanoherbal can be said as improving the extraction ratio of asiatic acid compared to the coarse powders due to the smaller particle size and larger surface area and the disappearance of asiaticoside still not completely understood.

Influence of milling time on fineness of Centella Asiatica particle size produced using planetary ball mill

Centella Asiatica (C. Asiatica)contains asiaticoside as bioactive constituent which can be potentially used in skin healing process. Unfortunately, the normal powders are difficult to be absorbed by the body effectively. In order to improve the value of use, nano C. Asiatica powder was prepared. The influence of milling time was carried out at 0.5, 2, 4, 6, 8 hours and 10 hours. The effect of ball milling at different times was characterized using particles size analysis and FTIR Spectroscopy. The fineness of ground product was evaluated by recording the z-Average (nm), undersize distribution and polydispersity index (PdI). The results show that the smallest size particles by mean is 233 nm while FTIR spectra shows that there is no changing in the major component in the C. Asiatica powders with milling time.

Effect of Bead Size on Fineness of Centella asiatica (C. asiatica) Particles in Wet Grinding

Nanoparticles are now essential material to be used in material engineering, medicine and cosmetic application due to their chemical, mechanical and optical properties. Several experiments were designed to investigate the relationship effect of bead size using different bead size (4 mm and 2 mm) at fix grinding conditions. Changes in particles size produce were studied using dynamic light scattering method at 25 °C. The z-Average and polydipersity index for each particles size at different grinding were recorded. Using smaller size of zirconia bead will produced smaller size of C. asiatica than using larger bead size. As a result the smallest size particle by mean is 242 nm where 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition at 517 nm shows the smaller particles has a higher percentage of inhibition.

Analyses of Heavy Metal Content in Different Particles Size of Centella asiatica

Arsenic (As), Cadmium (Cd) and Lead (Pb) are the heavy metal and categorized as high toxicity compound. This element can be found in the animal and plant from bio accumulation mechanism. This bio accumulation will lead to the toxicity when its concentration surpasses regulated value. Centella asiatica is a plant belonging to the Umbelliferae family, hydrocotyle order, which has been used for curing of venous ulcers and venous hypertension for its activity on connective tissue metabolism and endothelial integrity. This plant also widely used in formulation of drugs and cosmetic. In order to produce high quality herbal product, the characterization and standardization of heavy metal content using modern technique must be carried out. Centella asiatica nanopowders were produced at different grinding condition and analyzed for As content using ICP-OES (Optima 7300 DV, Perkin Elmer). The confirmations of size were carried out using nanoZeta Sizer S (Malvern Instrument) and Field Emission Scanning Electron Microscope. The results obtained show that As, Cd and Pb presence in all type of grinding below the acceptable daily intake by the world health organization (WHO).