In vitro antiproliferative and antioxidant activities of the extracts of Muntingia calabura leaves.

The in vitro antiproliferative and antioxidant activities of the aqueous, chloroform and methanol extracts of Muntingia calabura leaves were determined in the present study. Assessed using the 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay, the aqueous and methanol extracts of M. calabura inhibited the proliferation of MCF-7, HeLa, HT-29, HL-60 and K-562 cancer cells while the chloroform extract only inhibited the proliferation of MCF-7, HeLa, HL-60 and K-562 cancer cells. Interestingly, all extracts of M. calabura, which failed to inhibit the MDA-MB-231 cells proliferation, did not inhibit the proliferation of 3T3 (normal) cells, indicating its safety. All extracts (20, 100 and 500 μg/ml) were found to possess antioxidant activity when tested using the DPPH radical scavenging and superoxide scavenging assays with the methanol, followed by the aqueous and chloroform, extract exhibiting the highest antioxidant activity in both assays. The total phenolic content for the aqueous, methanol and chloroform extracts were 2970.4 ± 6.6, 1279.9 ± 6.1 and 2978.1 ± 4.3 mg/100 g gallic acid, respectively. In conclusion, the M. calabura leaves possess potential antiproliferative and antioxidant activities that could be attributed to its high content of phenolic compounds, and thus, needs to be further explored

Recent trend in residual palm oil recovery in a solid state fermentation

Production of palm oil from palm oil mill industries has been facing a serious challenge of overcoming the oil loss as a result of the mechanical extraction process limitations, consequently, leading to economic and environmental impacts. Efforts were made to overcome this impasse by mechanical process, dissolve air flotation, solvent extraction and enzymatic treatment. Most of these methods applied are faced with a somewhat drawbacks. In this review, the various methods of residual palm oil recovery were discussed, while presenting a better method that could allow for optimum recovery with less or no environmental impact via microbial means in a solid state process. Biological process in a solid state condition with fungi such as the white rot basidiomycetes is considered the best for future application, due to the natural availability of the fungi and high degrading capability of lignocellulose biomass. This would significantly be of benefit in terms of abating the huge oil palm mesocarp fiber deposition and aid in meeting the environmental requirement of waste consumption from the source

Numerical Study for MHD Stagnation-Point Flow of a Micropolar Nanofluid Towards a Stretching Sheet

In this paper, we investigated the magnetohydrodynamic (MHD) stagnation-point flow of micropolar nanofluid over a stretching sheet. A uniform magnetic field is applied normal to the flow. Nonlinear micropolar nanofluid problem in the presence of the strong concentration of microelements is modeled and then solved by numerical techniques. A parametric study of the involved parameters in the presence of spin gradient viscosity is conducted, and representative set of numerical results is illustrated in the graphical and tabular forms. The complete formulation of the Keller-box method for the considered flow problem is given, and a comparison of the obtained results is performed with the previous published results. The comparison shows that our present results have an excellent match with the previous results in a limiting case. We found that the non-dimensional temperature and its associated thermal boundary layer thickness are enhanced when we use the larger values of thermophoresis and Brownian motion parameter. The non-dimensional concentration is higher for larger thermophoresis parameter but smaller for higher Brownian motion parameter. It is also observed that the smaller values of Lewis number correspond to higher non-dimensional concentration and its associated boundary layer thickness

Active drag reduction in hydrocarbon media using rotating disk apparatus

A high precision rotating disk apparatus (RDA) is designed and employed to investigate the turbulent drag reduction characterization induced by polymeric additives. For the past few decades, polymers have been used widely as drag reducer agents in a pipeline and RDA successfully due to its viscoelastic properties that can suppress the turbulent at high ranges of Reynolds number. In this study, drag reduction efficacy of diesel fuel in a rotating disk apparatus is investigated using high molecular weight polyisobutylene polymer as drag reducing agent. Dependence of drag reduction on different parameters such as: polymer concentration and rotational disk speed (RPM) are also investigated. In addition, the mechanical stability of this polymer with time was studied by measuring torque values for 300 sec at a fixed rotational speed (2000 rpm). It was observed that the drag reduction of diesel fuel increases withthe rotational disk speed and polymer concentration till a critical concentration at which the maximum drag reduction achieved. The maximum DR obtained was about 19.197% at Re = 902062 and PIB concentration of 150 ppm

Zingiber zerumbet (L.) Smith: A Review of Its Ethnomedicinal, Chemical, and Pharmacological Uses

Zingiber zerumbet Sm., locally known to the Malay as “Lempoyang,” is a perennial herb found in many tropical countries, including Malaysia. The rhizomes of Z. zerumbet, particularly, have been regularly used as food flavouring and appetizer in various Malays' cuisines while the rhizomes extracts have been used in Malay traditional medicine to treat various types of ailments (e.g., inflammatory- and pain-mediated diseases, worm infestation and diarrhea). Research carried out using different in vitro and in vivo assays of biological evaluation support most of these claims. The active pharmacological component of Z. zerumbet rhizomes most widely studied is zerumbone. This paper presents the botany, traditional uses, chemistry, and pharmacology of this medicinal plant

Rotating Disk Apparatus: Types, Developments and Future Applications

Power consumption reduction investigations attracted the attention of enormous numbers of researchers in the past few decades due to its high academic and economic impacts. The pumping power losses during the transportation of crude oils are considered as one of the main power consuming applications due to the turbulent mode of transportation. Investigating the possible solutions for this problem is expensive and time consuming due to the large apparatuses needed to simulate the flow in real pipelines. Rotating disk apparatus (RDA) is an instrument mainly comprising a rotating disk and an electrical motor to rotate the disk, which was implemented as an efficient and economical path to simulate what can be done in pipelines through generating a controlled degree of turbulence. This technique was also used in many other scientific applications due to its dynamic mode of operation. For example, a rotating disk electrode was used in electrodeposition processes and to characterize deposition film thickness and uniformity. The rotating disk reactor was employed to investigate the reaction rate between fluids and solid surfaces. The present work evaluates the RDA from different prospective and applications in order to introduce it as an efficient research tools for future dynamic investigations

The Potential of Treated Palm Oil Mill Effluent (Pome) Sludge as an Organic Fertilizer

Palm oil mill contributed a significant benefit to agro-based industry and social-economic for Malaysia. Palm oil mill effluent (POME) is considered as a polluted wastewater and the treated POME sludge was produced from the open treatment ponds. The objective of this study was to determine the physicochemical characteristics of treated POME sludge and its potential as an organic fertilizer. It was collected from the dumping ponds in Felda Jengka 8, palm oil mill. Physicochemical characteristics, sampling and preparation of samples were analyzed according to the standard method of soil and the wastewater. The samples were collected after one and six month of age with different depths (one, two and three meters). The statistical analysis revealed that the depth was not significant on the physicochemical characteristics. The characteristics of the treated POME sludge was measures using CHNS-O, C/N ratio, solid analysis, heavy metal, macro and micronutrient, moisture content, and pH. However, the elements of oxygen, iron and pH were shown an interaction effects with time. In conclusion, the treated POME sludge has shown significant effect and the potential used as an organic fertilizer. Indeed, further studies on crops response are being conducted to prove the findings