Progress on Modified Calcium Oxide Derived Waste-Shell Catalysts for Biodiesel Production

The dwindling of global petroleum deposits and worsening environmental issues have triggered researchers to find an alternative energy such as biodiesel. Biodiesel can be produced via transesterification of vegetable oil or animal fat with alcohol in the presence of a catalyst. A heterogeneous catalyst at an economical price has been studied widely for biodiesel production. It was noted that various types of natural waste shell are a potential calcium resource for generation of bio-based CaO, with comparable chemical characteristics, that greatly enhance the transesterification activity. However, CaO catalyzed transesterification is limited in its stability and studies have shown deterioration of catalytic reactivity when the catalyst is reused for several cycles. For this reason, different approaches are reviewed in the present study, which focuses on modification of waste-shell derived CaO based catalyst with the aim of better transesterification reactivity and high reusability of the catalyst for biodiesel production. The catalyst stability and leaching profile of the modified waste shell derived CaO is discussed. In addition, a critical discussion of the structure, composition of the waste shell, mechanism of CaO catalyzed reaction, recent progress in biodiesel reactor systems and challenges in the industrial sector are also included in this review

Nanolayered composite with enhanced ultraviolet ray absorption properties from simultaneous intercalation of sunscreen molecules

Sumaiyah Megat Nabil Mohsin,1 Mohd Zobir Hussein,2 Siti Halimah Sarijo,3 Sharida Fakurazi,4,5 Palanisamy Arulselvan,6,7 Yun Hin Taufiq-Yap8 1Advanced Oleochemical Technology Division (AOTD), Malaysian Palm Oil Board (MPOB), Kajang, Selangor, Malaysia; 2Material Synthesis and Characterization Laboratory (MSCL), Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 3Faculty of Applied Science, Universiti Teknologi MARA, Shah Alam, Selangor, Malaysia; 4Department of Human Anatomy, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 5Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 6Muthayammal Centre for Advanced Research, Muthayammal College of Arts and Science, Rasipuram, Namakkal, Tamil Nadu, India; 7Scigen Research and Innovation, Periyar Technology Business Incubator, Thanjavur, Tamil Nadu, India; 8Catalysis Science and Technology Research Centre, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Introduction: The potential of layered double hydroxide (LDH) as a host of multiple ultraviolet-ray absorbers was investigated by simultaneous intercalation of benzophenone 4 (B4) and Eusolex® 232 (EUS) in Zn/Al LDH.Methods: The nanocomposites were prepared via coprecipitation method at various molar ratios of B4 and EUS.Results: At equal molar ratios, the obtained nanocomposite showed an intercalation selectivity that is preferential to EUS. However, the selectivity ratio of intercalated anions was shown to be capable of being altered by adjusting the molar ratio of intended guests during synthesis. Dual-guest nanocomposite synthesized with B4:EUS molar ratio 3:1 (ZEB [3:1]) showed an intercalation selectivity ratio of B4:EUS =53:47. Properties of ZEB (3:1) were monitored using powder X-ray diffractometer to show a basal spacing of 21.8 Å. Direct-injection mass spectra, Fourier transform infrared spectra, and ultraviolet–visible spectra confirmed the dual intercalation of both anions into the interlayer regions of dual-guest nanocomposite. The cytotoxicity study of dual-guest nanocomposite ZEB (3:1) on human dermal fibroblast cells showed no significant toxicity until 25 µg/mL. Conclusion: Overall, the findings demonstrate successful customization of ultraviolet-ray absorbers composition in LDH host. Keywords: biocompatibility, cell viability, dermis, layered double hydroxide, nanocomposit

Parametric characterisation of air gasification of chlorella vulgaris biomass

The gasification of green algae Chlorella vulgaris in air was investigated using both a thermogravimetric analyzer (TGA) and a bench scale horizontal axis quartz tube reactor (HQR). The full range of solid state kinetic models produced best fits with TGA results varied for the 5 subzones of conversion vs. temperature, with the nucleation and nuclei growth ‘A2’ followed by ‘A3’ or contracting volume models producing close matches for T ≤ 367 °C, zero order model between 358 and 468 °C, and contracting surface models for T ≥ 458 °C, each model yielding their set of apparent activation energy (E 0.04 s¯¹) corresponding to rate constants in the range 0.001 to 0.005 s¯¹. The HQR was used to investigate the effects of microalgal biomass loading, temperature and equivalence ratio (ER) on CnHm/CO/H₂ gas yield and composition, carbon conversion efficiency (CCE) and lower heating value (LHV) of syngas under air gasification conditions. Increasing microalgal biomass loading from 1 to 2 g led to a decrease in H2 content (24.2 to 19.5 vol. %) in the gases. An optimal temperature of 950 °C resulted in the highest H₂, CO and CH₄ yields at 2.9, 22.8 and 10.1 wt. % of biomass from a maximum gas yield of 76.1 wt. %, and highest H₂/CO ratio (1.75) and CCE of 56.3 %. The effect of ER was measured in two phases 0.1 to 0.26 and 0.26 to 35, respectively. During the first phase, the positive effect of ER performed a major part compared to second phase, so as the H₂ content, H₂ yield, CCE and LHV were increased

Anticancer effect of dentatin and dentatin-hydroxypropyl-β-cyclodextrin complex on human colon cancer (HT-29) cell line

Ashwaq Shakir AL-Abboodi,1,2 Abdullah Rasedee,3 Ahmad Bustamam Abdul,1,4 Yun Hin Taufiq-Yap,5 Wafaa Abd Alwahed Alkaby,6 Mostafa Saddam Ghaji,7 Peter M Waziri,1,8 Mothanna Sadiq Al-Qubaisi1 1MAKNA-UPM, Cancer Research Laboratory, Institute of Bioscience, University Putra Malaysia, Serdang, Malaysia; 2Basic Science Branch, Faculty of Dentistry, University of Al-Qadisiyah, Al Diwaniyah, Iraq; 3Department of Veterinary Laboratory Diagnosis, Faculty of Veterinary Medicine, University Putra Malaysia, Serdang, Malaysia; 4Department of Biomedical Science, Faculty of Medicine and Health Science, University Putra Malaysia, Serdang, Malaysia; 5Department of Chemistry, Faculty of Science, University Putra Malaysia, Serdang, Malaysia; 6Department of Biomedical, Faculty of Biotechnology, University of AL-Qadisiyah, Al Diwaniyah, Iraq; 7Department of Anatomy and Histology, Faculty of Veterinary Medicine, University of Basrah, Basrah, Iraq; 8Department of Biochemistry, Kaduna State University, Main Campus,  Kaduna, Nigeria Introduction: Dentatin (DEN) (5-methoxy-2, 2-dimethyl-10-(1, 1-dimethyl-2propenyl) dipyran-2-one), a natural compound present in the roots of Clausena excavata Burm f, possesses pro-apoptotic and antiproliferative effects in various cancer cells. Because of its hydrophobicity, it is believed that its complexation with hydroxy-β-cyclodextrin (HPβCD) will make it a potent inhibitor of cancer cell growth. In the current work, the molecular mechanisms of apoptosis induced by DEN and DEN-HPβCD complex were demonstrated in human colon HT-29 cancer cells.Materials and methods: After the human colon HT-29 cancer cells were treated with DEN and DEN-HPβCD complex, their effects on the expression of apoptotic-regulated gene markers in mitochondria-mediated apoptotic and death receptor pathways were detected by Western blot analysis and reverse transcription polymerase chain reaction. These markers included caspases-9, 3, and 8, cytochrome c, poly (ADP-ribose) polymerase, p53, p21, cyclin A as well as the Bcl-2 family of proteins.Results: At 3, 6, 12, and 24 µg/mL exposure, DEN and DEN-HPβCD complex significantly affected apoptosis in HT-29 cells through the down-regulation of Bcl-2 and cyclin A in turn, and up-regulation of Bax, p53, p21, cytochrome c at both protein and mRNA levels. DEN and DEN-HPβCD complex also decreased cleaved poly (ADP-ribose) polymerase and induced caspases-3, -8, and -9.Conclusion: Results of this study indicate that the apoptotic pathway caused by DEN and DEN-HPβCD complex are mediated by the regulation of caspases and Bcl-2 families in human colon HT-29 cancer cells. The results also suggest that DEN-HPβCD complex may have chemotherapeutic benefits for colon cancer patients. Keywords: natural products, HPβCD, apoptosis, pro-apoptotic proteins, anti-apoptotic protein

Physicochemical properties, cytotoxicity, and antimicrobial activity of sulphated zirconia nanoparticles

Ae Mftah,1 Fatah H Alhassan,2,3 Mothanna Sadiq Al-Qubaisi,4 Mohamed Ezzat El Zowalaty,4 Thomas J Webster,5,6 Mohammed Sh-eldin,7 Abdullah Rasedee,8 Yun Hin Taufiq-Yap,2,3 Shah Samiur Rashid1 1Department of Chemistry, Faculty of Industrial Sciences and Technology, University Malaysia Pahang, Malaysia; 2Catalysis Science and Technology Research Centre, 3Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Selangor, Malaysia; 4Institute of Bioscience, University Putra Malaysia, Serdang, Selangor, Malaysia; 5Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 6Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia; 7Solar Energy Research Institute, University Kebangsaan Malaysia, Selangor, 8Faculty of Veterinary Medicine, Universiti Putra Malaysia, Selangor, Malaysia Abstract: Nanoparticle sulphated zirconia with Brønsted acidic sites were prepared here by an impregnation reaction followed by calcination at 600°C for 3 hours. The characterization was completed using X-ray diffraction, thermal gravimetric analysis, Fourier transform infrared spectroscopy, Brunner-Emmett-Teller surface area measurements, scanning electron microscopy with energy dispersive X-ray spectroscopy, and transmission electron microscopy. Moreover, the anticancer and antimicrobial effects were investigated for the first time. This study showed for the first time that the exposure of cancer cells to sulphated zirconia nanoparticles (3.9–1,000 µg/mL for 24 hours) resulted in a dose-dependent inhibition of cell growth, as determined by (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Similar promising results were observed for reducing bacteria functions. In this manner, this study demonstrated that sulphated zirconia nanoparticles with Brønsted acidic sites should be further studied for a wide range of anticancer and antibacterial applications. Keywords: sulphated zirconia, nanoparticles, antimicrobial, anticance

Cytotoxicity and physicochemical characterization of iron–manganese-doped sulfated zirconia nanoparticles

Mohamed Qasim Al-Fahdawi,1 Abdullah Rasedee,1,2 Mothanna Sadiq Al-Qubaisi,1 Fatah H Alhassan,3,4 Rozita Rosli,1 Mohamed Ezzat El Zowalaty,1,5 Seïf-Eddine Naadja,6 Thomas J Webster,7,8 Yun Hin Taufiq-Yap3,41Institute of Bioscience, 2Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, 3Catalysis Science and Technology Research Centre, Faculty of Science, 4Department of Chemistry, Faculty of Science, 5Biomedical Research Center, Qatar University, Doha, Qatar; 6Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia (UPM), Serdang, Selangor, Malaysia; 7Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 8Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi ArabiaAbstract: Iron–manganese-doped sulfated zirconia nanoparticles with both Lewis and Brønsted acidic sites were prepared by a hydrothermal impregnation method followed by calcination at 650°C for 5 hours, and their cytotoxicity properties against cancer cell lines were determined. The characterization was carried out using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, Brauner–Emmett–Teller (BET) surface area measurements, X-ray fluorescence, X-ray photoelectron spectroscopy, zeta size potential, and transmission electron microscopy (TEM). The cytotoxicity of iron–manganese-doped sulfated zirconia nanoparticles was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays against three human cancer cell lines (breast cancer MDA-MB231 cells, colon carcinoma HT29 cells, and hepatocellular carcinoma HepG2 cells) and two normal human cell lines (normal hepatocyte Chang cells and normal human umbilical vein endothelial cells [HUVECs]). The results suggest for the first time that iron–manganese-doped sulfated zirconia nanoparticles are cytotoxic to MDA-MB231 and HepG2 cancer cells but have less toxicity to HT29 and normal cells at concentrations from 7.8 µg/mL to 500 µg/mL. The morphology of the treated cells was also studied, and the results supported those from the cytotoxicity study in that the nanoparticle-treated HepG2 and MDA-MB231 cells had more dramatic changes in cell morphology than the HT29 cells. In this manner, this study provides the first evidence that iron–manganese-doped sulfated zirconia nanoparticles should be further studied for a wide range of cancer applications without detrimental effects on healthy cell functions.Keywords: nanopartices, Lewis and Brønsted acidic sites, anticancer applications, HT29 cells, transition metal oxid