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In this paper, the effect of different synthesis methods, such as controlled precipitation (CP), sonochemical (SC), hot solution ion injection with fast cooling, and conventional hydrothermal (CH) in obtaining beta-disilver molybdate (β-Ag 2 MoO 4 ) are explained in details. X-ray diffraction patterns, Rietveld refinement data, cluster modeling, micro-Raman, and Fourier transform infrared spectroscopies confirmed that all β-Ag 2 MoO 4 crystals have a spinel-like cubic structure, space group (Fd 3 m), and symmetry point group (O 7 h ). Field emission scanning electron microscopy (FE-SEM) images showed that through different synthetic routes, it is possible to obtain monophasic crystals, such as regular/irregular polyhedrons (cubes, cuboctahedron, trapezohedron, rhombic dodecahedron), potatoes, and non-uniform. The crystal shape observed experimentally was modeled based on Rietveld refinement data and FE-SEM images obtained by KrystalShaper. First-principles quantum mechanical calculations based on density functional theory were employed to modulate the surfaces of the material and to obtain their surface energy (E surf ) values. From these E surf values in association with the Wulff construction, the evolution of the crystals shape was achieved correlating with the experimental results when different synthesis methods are used. Ultraviolet-Visible (UV-Vis) spectroscopy measurements in absorbance mode showed three main absorptions (280, 310, and 340 nm), while the UV-Vis analyses in diffuse reflectance mode showed a tail of energy absorption in the UV spectrum range (3.25 eV and 3.3 eV). The quantitative data from the colorimetric analysis indicated that the β-Ag 2 MoO 4 crystals are desirable for developing inorganic pigments with a beige to brown shade. Photocatalytic assays were performed using four lamps: UV-C, UV-B, UV-A, and visible light. The β-Ag 2 MoO 4 crystals prepared by the CP method showed a higher degradation rate at 85.12% for the rhodamine B dye solution under 240 min exposure to UV-C light.

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Herbal medicines based on Ginkgo biloba L. and Bacopa monnieri L. are used to improve memory and cognitive function. The quality control and anticholinesterase activity of the herbal medicines prepared from G. biloba and B. monnieri were evaluated which are commercialized in handling pharmacies. Samples of herbal medicines based on G. biloba and B. monnieri were obtained from handling pharmacies in Teresina-PI, submitted to labeling analysis and anticholinesterase activity. The phytochemical study was performed by preliminary prospecting, TLC and HPLC. The tests physicochemical and microbiological analyses were made according to the Pharmacopoeia 2010. It was observed that the labeling, foreign material, disintegration, and microbiological parameters were in accordance with ANVISA standards. The colorimetric tests were uniform in the samples of B. monnieri and variable of G. biloba. The average weight evaluation shows that the G1 and B3 samples have capsular content above that described in the labeling and presented pH values ​​different. Among the thermogravimetric profiles, the mass losses of samples G1 and B3 showed values ​​with high ash content, suggesting adulterations. Phytochemical prospecting showed flavonoids as common secondary metabolites in both species, corroborating with TLC and HPLC analysis, which identified the compounds chlorogenic acid, rutin, myricetin and quercetin. The samples G4, B2 and B5 present metabolites capable of inhibiting the enzyme acetylcholinesterase with IC50 of 0.8540 mg/mL, 0.9650 mg/mL and 1.8221×10-5 mg/mL, respectively. The samples G1 and B3 of G. biloba and B. monnieri, did not obey some parameters of quality control for herbal medicines according to the criteria of the Brazilian Pharmacopeia.

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