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Introduction: The study was intended for Roseomonas gilardii NTCC 13290 strain pigment extraction and characterization. Methodology: The pigment-producing bacterial were cultured on Columbia blood agar and nutrient media agar. Then the pigments were extracted by ethanol. The candidate pigment was further characterized by different biotechnological techniques: UV-Vis spectroscopy, FT-IR to analyze the functional group of the targeted pigment, and TLC media. Results: The cultivation of Roseomonas gilardii on media showed pink color and nearly runny texture. The bacterial colonies were microscopically gram stained and examined, the R. gilardii was seen as coccobacillus colonies that mostly form pairs arranged as short chains. The R. gilardii bacteria that produce pink pigment was elected then further propagated for several days. The maximum spectrophotometric absorbance spectrum for the extracted pigment was observed at 500 nm, the functional groups were identified via FT-IR analysis revealed the presence of alcohol, alkenes, alkanes, phenols and carboxylic acid, in addition to iodine. The Rf value was equal to 0.80 in TLC method. Conclusions: Based on the current results, the extracted pigment from Roseomonas gilardii may serve as for food, cosmetic, and textile industries as a natural colorant from bacterial origin. [ABSTRACT FROM AUTHOR]

The present study applied LA–ICP-MS on gem-quality emeralds from the most important sources (Afghanistan, Brazil, Colombia, Ethiopia, Madagascar, Russia, Zambia and Zimbabwe). It revealed that emeralds from Afghanistan, Brazil, Colombia and Madagascar have a relatively lower lithium content (7Li < 200 ppmw) compared to emeralds from other places (7Li > 250 ppmw). Alkali element contents as well as scandium, manganese, cobalt, nickel, zinc and gallium can further help us in obtaining accurate origin information for these emeralds. UV-Vis spectroscopy can aid in the separation of emeralds from Colombia and Afghanistan from these obtained from the other sources as the latter present pronounced iron-related bands. Intense Type-II water vibrations are observed in the infrared spectra of emeralds from Madagascar, Zambia and Zimbabwe, as well as in some samples from Afghanistan and Ethiopia, which contain higher alkali contents. A band at 2818 cm−1, supposedly attributed to chlorine, was observed only in emeralds from Colombia and Afghanistan. Samples with medium to high alkalis from Ethiopia, Madagascar, Zambia and Zimbabwe can also be separated from the others by Raman spectroscopy based on the lower or equal relative intensity of the Type I water band at around 3608 cm−1 compared to the Type II water band at around 3598 cm−1 band (with some samples from Afghanistan, Brazil and Russia presenting equal relative intensities). [ABSTRACT FROM AUTHOR]