Sulfated zirconia catalysts were prepared by wetness impregnation of zirconium hydroxide with an aqueous solution of (NH4)2SO4 with SO42− loadings (1–30%, w/w) and calcined at 450 °C for 3 h in a static air atmosphere. The catalysts were characterized by FT-IR, XRD, TEM and BET measurements. The surface acidity of the catalysts was investigated by the dehydration of isopropanol and the adsorption of pyridine (PY) and 2,6-dimethyl pyridine (DMPY). The catalysts were tested for dehydration of methanol in a fixed-bed reactor at 230 °C using air as a carrier gas. The results revealed that among different catalysts, 10% SO42− supported onto zirconia showed the highest catalytic activity with 83% conversion and 100% selectivity toward dimethyl ether. A good correlation was found between the acidity of the catalysts and their ability to dehydrate methanol.

Sulfated zirconia catalysts were prepared by wetness impregnation of zirconium hydroxide with an aqueous solution of (NH4)2SO4 with SO42− loadings (1–30%, w/w) and calcined at 450 °C for 3 h in a static air atmosphere. The catalysts were characterized by FT-IR, XRD, TEM and BET measurements. The surface acidity of the catalysts was investigated by the dehydration of isopropanol and the adsorption of pyridine (PY) and 2,6-dimethyl pyridine (DMPY). The catalysts were tested for dehydration of methanol in a fixed-bed reactor at 230 °C using air as a carrier gas. The results revealed that among different catalysts, 10% SO42− supported onto zirconia showed the highest catalytic activity with 83% conversion and 100% selectivity toward dimethyl ether. A good correlation was found between the acidity of the catalysts and their ability to dehydrate methanol.

Abstract
Skin injuries, congenital lesions, melasma, Addison's disease and many pigment abnormalities prompt us to search for an effective whitening agent. Ideal whitening agent is a natural compound that can inhibit melanogenesis and has no cytotoxic effects. In a previous study, we have developed an optimum method for the production and characterization of ectoine from a halophilic bacterium isolated from a salt environment in Taiwan was identified as Marinococcus sp. In the present study, we screened the whitening properties of the biosynthesized ectoine using mouse and human melanoma cell lines, B16-F0 and A2058. Here, we examined the cell viabilities of melanoma cells after ectoine treatment at various concentrations up to 500 μM. Also, we addressed the melanin synthesis of melanoma cells after treatment with ectoine. The inhibitory effects of ectoine on tyrosinase activity were assessed in both mushroom tyrosinase and cellular tyrosinase. Furthermore, we investigated the type of inhibition of mushroom tyrosinase using Lineweaver–Burk enzyme kinetic. The melanogenesis-related gene expression (tyrosinase, TRP1, TRP2 and MITF) and their protein secretion were determined by the assays of quantitative real-time PCR and western blots, respectively. Our results demonstrated that ectoine is a safe and effective whitening agent, inhibited melanin synthesis, reduced both mushroom tyrosinase and cellular tyrosinase, and had various inhibitory effects on the expressions of melanogenesis-related genes and secretion of proteins in mouse and human melanoma cell lines. Thus, we suggest that ectoine can serve as a useful and safe new agent in cosmetic and clinical applications.

Abstract
Currently, many gastrointestinal diseases are a major reason for the increased mortality rate of children and adults every year. Additionally, these patients may cope with the high cost of the parenteral nutrition (PN), which aids in the long-term survival of the patients. Other treatment options include surgical lengthening, which is not sufficient in many cases, and intestinal transplantation. However, intestinal transplantation is still accompanied by many challenges, including immune rejection and donor availability, which may limit the transplant’s success. The development of more safe and promising alternative treatments for intestinal diseases is still ongoing. Stem cell-based therapy (SCT) and tissue engineering (TE) appear to be the next promising choices for the regeneration of the damaged intestine. However, suitable stem cell source is required for the SCT and TE process. Thus, in this review we discuss how intestinal stem cells (ISCs) are a promising cell source for small intestine diseases. We will also discuss the different markers were used to identify ISCs. Moreover, we discuss the dominant Wnt signaling pathway in the ISC niche and its involvement in some intestinal diseases. Additionally, we discuss ISC culture and expansion, which are critical to providing enough cells for SCT and TE. Finally, we conclude and recommend that ISC isolation, culture and expansion should be considered when SCT is a treatment option for intestinal disorders. Therefore, we believe that ISCs should be considered a cell source for SCT for many gastrointestinal diseases and should be highlighted in future clinical applications.

Abstract
Intestinal stem cells (ISCs) are located at the base of the intestinal crypts and have the ability to self-renew as well as to differentiate into mature epithelial cells. Recently, ISCs have received much attention for the treatment of many intestinal diseases. However, many challenges face those studying ISCs because insufficient ISCs are available. Therefore, the development of a culture medium for ISC expansion is an important necessity for basic research and clinical application. In this study, we described the technique used to develop a serum-free medium for expanding ISCs in vitro. Furthermore, five serum substitutes were selected and optimized in order to maintain the long-term proliferation and enteroid-forming ability of ISCs: (i) ethanolamine; (ii) ascorbic acid phosphate; (iii) transferrin; (iv) glutathione; and (v) sodium selenite. Analysis of gene expression of Lgr5, Bmi1, Msi1 and PTEN demonstrated that our serum-free medium sustained the expression of genes involved in ISC-related functions in the expanded ISCs. Additionally, the expression intensity of surface markers, including Lgr5, CD24 and CD44, on serum-free expanded cells in crypts was greatly increased. Taken together, our results demonstrate that the number of ISCs can be expanded and their functionality maintained in our serum-free medium, indicating the suitability of this serum-free expansion medium for increasing the numbers of ICSs available for basic research and clinical applications in the future.

Studying of nanoparticle structures is gaining
momentum because of their great potential in improving
several fields of science such as agriculture. The water
soluble fraction of the extracellular polysaccharides
(EPS)/matrix of the highly EPS producing cyanobacterium
Nostoc commune have been used as a potent reducing and
capping agent for green synthesis of silver nanoparticles.
The size of these nanoparticles with the EPS coat was found
to be in the range of 15–54 nm as analyzed using
transmission electron micrographs. Interestingly, after
washing the EPS coated silver nanoparticles by ethanol, the
size of nanoparticles reduced to less than 15 nm due to the
formation of silver oxide nanoparticles and removal of the
EPS coat. Silver nanoparticles showed antibacterial
properties against Escherichia coli. The minimum inhibitory
concentration (MIC) was 0.012 mg/ml while the minimum
bactericidal concentration (MBC) was 0.016 mg/ml. The
slight difference between the MIC and MBC suggests that
such silver nanoparticles act as a potent bactericidal agent
against E. coli. Presoaking seeds of crop plants (Sorghum
and broad bean) in five-fold MBC of silver nanoparticles
(0.08 mg/ml) did not adversely affect the germination of
Vicia faba L. and Sorghum bicolor plants. Concomitantly,
such fivefold MBC concentration of silver nanoparticles was
powerful sterilizing agent for seeds and grains against
seed/grain-borne microorganisms. The results showed
gradual depletion of the total colony forming units (CFU) in
seeds and grains sterilized with silver nanoparticles than
those sterilized with chlorine. These results suggest that the
water soluble fraction of the extracellular polysaccharides
(EPS)/matrix of Nostoc commune can be used as a potent
reducing and capping agent for green synthesis of silver
nanoparticles and that silver nanoparticles can be used as a
potent surface sterilizi