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Clinacanthus nutans (C. nutans) herb is one of the medicinal herbal species from Acanthaceae family. This plant is native to tropical and subtropical Asian regions. It is mostly cultivated in Malaysia, Thailand, and Indonesia. In Thailand, C. nutans was initially invented as an antiviral cream and clinically proven to treat herpes simplex virus (HSV) and varicella-zoster virus (VZS) infections (Charuwichitrat et al., 1996;Jayavasu et al., 1992;Sangkitporn et al., 1995). The cream also exhibited anti-dengue property. Another vital medicinal benefit of the C. nutans herb is as an anticancer. Numerous studies have revealed the cytotoxicity and antiproliferative effects of C. nutans extract against various human cancer cell lines such as

Drying is a well-known preservation method that uses to extent the shelf life of food materials during storage. In herbal industry, the drying is conducted by using several methods. It is believed that drying methods could affect the herbs physical and chemical properties. In this project, the effects of different drying methods on colour changes, rehydration ratio and bioactive constituent of C. nutans herb were investigated. The herb was dried under sunlight, shade, vacuum oven, and microwave. Results showed that the dried leaves have better retention of TPC and higher antioxidant activity as compared to the fresh leaves. Vacuum oven dried samples showed the highest antioxidant activity and significantly high in TPC. Besides, vacuum and under shade dried herbal leaves had no significant effect on the colour changes. Moreover, leaves dried under vacuum oven was also observed to exert the highest rehydration ratio due to less cell breakdown during drying. Therefore, vacuum drying has greater performance in term of retaining colour, less microstructure changes and greater TPC and antioxidant activity. It could be suggested that by adding vacuum to other drying methods may able to enhance the herbal quality.

Fish cracker is a popular snack in Malaysia. In preparation of fish cracker, drying is one of the important steps. Drying is used as for the preservation of fish crackers during storage. In this study, the effects of different drying techniques on the drying kinetics of fish crackers were investigated. Fresh fish cracker samples were attained from two manufacturers in Tanjung Dawai Kedah, Malaysia which were Persatuan Nelayan Kawasan (M1) and Perusahaan Hasil Laut Musliha (M2). Samples were dried under sunlight, oven and vacuum oven. Results showed that M1 sample exhibited higher drying rate than M2 under all techniques. It is due to the difference in thickness. All of the drying kinetics fall under falling rate period except for M1 samples dried by vacuum oven. Mathematical modelling was performed to compare experimental drying kinetics with predicted data by Lewis model. Vacuum oven drying showed the best fit to the model which gave highest R 2 and lowest SSE, RMSE and c 2 as compared to sundry and oven. Therefore, data predicted by Lewis model could be used to describe the drying of fish cracker using vacuum oven.

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The development of high-temperature superconductor (HTS) YBa2Cu3O7~δ (Y123) bulks in industrial applications were established years ago. It is one of the developments that currently attracts great attention especially in transportation, superconductor cables and wires. This study is focused on the preparation of the Y123 bulk superconductors by the thermal treatment method due to the promising ways to develop high-quality Y123 superconductors with its simplicity, low cost, and relatively low reaction temperature used during the process. Y123 were added with graphene nanoparticles (x = (0.0–1.0) wt.%). Samples were then characterized by X-ray diffraction (XRD) analysis, field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), and alternating current susceptibility (ACS). It was found that Y123 confirmed that the majority of phases in all the XRD patterns was the orthorhombic crystal structure and the Pmmm space group with secondary phases belonged to Y2Ba1Cu1O5 (Y211). The highest Tc obtained when graphene nanoparticles were added in the Y123 sample was x = 1.0 wt.%, followed by x = 0.5 wt.% with 92.64 and 92.59 K, respectively. From the microstructure analysis, the average grain size significantly decreased to 4.754 µm at x = 0.5 wt.%. The addition of graphene nanoparticles had disturbed the grain growth of Y123, affecting the superconducting properties of the samples. On the other hand, the intergranular critical current density, Jcm, was found to increase with graphene nanoparticle addition and had the highest value at x = 1.0 wt.%, indicating that graphene nanoparticles acted as pinning centers in the Y123 matrix.