Optical properties of pure and doped poly(vinyl chloride) (PVC) films, prepared by using casting technique, with different nanosize zinc oxide (ZnO) concentrations (1–20) wt% have been studied. Parameters such as extinction coefficient, refractive index, real and imaginary parts, Urbach energy, optical conductivity, infinitely high frequency dielectric constant, and average refractive index were studied by using the absorbance and transmittance measurement from computerized UV-visible spectrophotometer (Shimadzu UV-1601 PC) in the spectral range 200–800 nm. This study reveals that the optical properties of PVC are affected by the doping of ZnO where the absorption increases and transmission decreases as ZnO concentration increases. The extinction coefficient, refractive index, real and imaginary parts, infinitely high frequency dielectric constant, and average refractive index values were found to increase with increasing impurity percentage. The Urbach energy values are found to be decreasing with increasing ZnO concentration. The optical conductivity increased with photon energy after being doped and with the increase of ZnO concentration.

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Presently, plant oils which contain high percentage of linoleic acid 1 are perceived to be a viable alternative to mineral oil for biolubricant applications due to their biodegradability and technical properties. In order to get biodegradable lubricant, triester derivatives compounds (1–5) were synthesized and characterized. The processes involved were monoepoxidation of linoleic acid 2, oxirane ring opening 3, esterification 4 and acylation 5. The structures of the products were confirmed by FTIR, 1H and 13C-NMR and LC-MS. The results that showed lowest temperature properties were obtained for triester 5, with a pour point value (PP) of -73°C, highest onset temperature (260°C) and lowest volatility at 0.30%. Viscosity index (VI) increased for the ester’s synthetic compounds (2, 3, 4, 5), while the PP decreased. This behavior is the result of the increase of the chain length of the branching agents. Triester based linoleic acid has improved properties such as low-temperature and tribological properties. These results will make it feasible for plant oil to be used for biolubricants, fuels in chain saws, transmission oil and brake fluid.

The study of cancer cell has been hindered by the lack of appropriate ex vivo models, which can mimic this microenvironment. It is hypothesized that the fabrication of porous 3-D scaffolds for the biomimetics growth of cancer cells ex vivo could facilitate the study of the disease in its native 3-D niche. For that reason, biomaterials are used for fabrication of 3-D scaffold, in general, may be natural polymers such as proteins, collagens and gelatin, or synthetic biopolymers. Among the various available biodegradable polymers, polyhydroxyalkanoates (PHAs) have gained significant interest as one of the value-added materials which can be synthesized from abundantly available source of palm oil mill effluent (POME). Down the group of the PHA, poly-3-hydroxybutyrate (PHB) and copolymerizing this PHB that produced PHBVs; these two polymers have the most prevalent polymer used for scaffolds fabrication. A physico-chemical and biological modification has developed to improve wetting, adhesion, and printing of polymer surfaces, generally by introducing a variety of polar groups. These techniques must be tailored to introduce a specific functional group when the surface modification is a precursor to attach a bioactive compound. There are a few methods in order to fabricate porous 3-D scaffolds such as solvent casting, particulate leaching, thermally induced phase separation, gas forming, fiber bonding, electrospinning and also solid free form method. A review of the polyhydroxyalkanoates (PHAs) for tissue engineering applications is presented, beginning with the basic naturally derived polymerization of PHAs, biotransformation of palm oil mill effluent (POME) to the value-added polymers, novel methods of scaffold fabrication capabilities and its physico-chemical and biological surface modifications to increase cell-biomaterial affinity.

Bio-pesticides are natural occurring substances that control pest and derived either from plants or microorganism. It play a vital role in coping with adverse effect arise due to massive used of synthetic pesticides and development of insecticide resistance of some insect groups in crop productions. Thus, Derris species from Leguminosae (Fabacea) family is a climbing plant of Southeast Asia that was well known for its environmental friendly bioactive compound is used as one of the effective insecticides. Rotenone was one of the bioactive constituents extracted from Derris plant that was used as agricultural pest control due to its strong paralysis action (knock-down effect) on cold blooded animals. Moreover, it has a lethal mechanism in inhibiting respiratory enzyme of insects and easily degrades which makes it environmental friendly. Extraction of rotenone commonly uses organic solvents as extractant either in non-conventional extraction methods or conventional method. Application of green solvents, ionic liquids as extractant is new approach for rotenone extraction. Indeed environmental friendly bio-pesticides have not been studied thoroughly and several approach and further study are required to produce high quality and environmental friendly bio-pesticides. In addition, biological assay such as “Brine Shrimp (Artemia salina) Lethality” study is also vital in order to determine a preliminary safe exposure limit of extracted rotenone prior to be used as pesticides. For that reason, a review of the environmental friendly bio-pesticide rotenone extracted from Derris sp. is presented herewith. This article reviews the up scaling extraction methods, toxicity and its effectiveness against several moth species such as Spodoptera litura and Plutella xylostella.