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This work studied the concretion components of ancient silk fabrics unearthed from Nanjing, China. Based on the analysis of the components, mechanism of concretion of the silk fabrics were proposed. Physical, chemical, and biological factors were considered as possible reasons for the concretion of ancient silk fabrics. Mechanical extrusion or falling, crystal bonding, Van der walls forces, hydrogen bonding, covalent bonding, and ionic bonding are purposed as possible influences and/or interactions between the concretion components and silk fabrics. The concretion mechanism, which includes common mineralization nucleation, re-crystallization, bio-mineralization nucleation and crystallization are discussed separately. Mineralization nucleation and crystallization have a great influence on the aging, hardening (even rotting), and final concreting of buried silk fabrics. Possible processing models were established according to the results obtained. This study presents new viewpoints to understand the concretion of unearthed silk fabrics, which could provide theoretical evidence for the unfolding of concreted silk fabrics, especially those fragile, even rotten ones. [ABSTRACT FROM AUTHOR]

Immunomagnetic beads (IMBs) are a new immunological separation technology for protein purification, etc. In this experiment, to enrich and purify trace silk fibroin from complex soil and cultural relics, an immunomagnetic separation method was developed through coupling anti-fibroin polyclonal antibodies with magnetic beads. The key parameters were optimized to prepare the IMBs and capture the fibroin. Under optimized conditions, the capture rate with 1.2 mg of IMBs against a 100 ng/mL-1 fibroin solution was greater than 99%. The recovery rate of fibroin in soil was over 97% when the silk fibroin additive content was 10 to 50 ng, which showed that the IMB method developed in this study could successfully enrich silk fibroin in soil for indirect enzyme-linked immunosorbent assay (iELISA) detection. The results of the respective analyses of fabric and mineralized textile samples indicated that IMBs could be successfully applied for the detection of trace silk fibroin in archaeological samples. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • 4α,5α-oxidoeudesm-11-en-3-one newly isolated from natural resources. • 4α,5α-oxidoeudesm-11-en-3-one exhibited potent estrogenic activity. • 4α,5α-oxidoeudesm-11-en-3-one showed higher binding affinity to ER-β than ER-α. • 4α,5α-oxidoeudesm-11-en-3-one showed both estrogenic and antiestrogenic effects depending on the E 2 concentration. Abstract Estrogenic activity-oriented fractionation and purification of methanol extract from the rhizome of Cyperus rotundus , a well-known traditional herbal medicine, led to the isolation of six sesquiterpenes. 4α,5α-Oxidoeudesm-11-en-3-one (2) and cyper-11-ene-3,4-dione (3) together with four known sesquiterpenes, cyperotundone (1), caryophyllene α-oxide (4), α-cyperone (5), and isocyperol (6) were obtained from the hexane and dichloromethane fractions. Compounds 2 and 3 were newly isolated from natural resources in particular. To identify the possible use of isolated compounds as an alternative to hormone replacement therapy (HRT), estrogenic activity was evaluated by E-screen assay on MCF-7 BUS cells. Among the all isolated compounds from the rhizome of Cyperus rotundus , newly isolated from natural resource, 2 exhibited the most potent estrogenic activity. In an estrogen sensitive reporter gene assay, 2 significantly increased transcriptional activities. As a phytoestrogen, 2 was assessed by investigating dual action on ER-α and ER-β in competitive binding assay. It was found that 2 exerted higher binding affinity to ER-β than ER-α and it also showed both estrogenic and antiestrogenic effects depending on the E 2 concentration. Our results indicate that newly isolated from Cyperus rotundus , 2 has biphasic activities on estrogen receptors which could be useful as an alternative HRT. [ABSTRACT FROM AUTHOR]

• Stable isotope technique was firstly used to analyze ancient and artificial aged silk fabrics. • The stable isotope ratios of ancient silk fabrics under various excavation environments display different trends. • Heavy stable isotopes were enriched during degradation of the silk fabrics under most aging conditions. • Degradation of silk fabrics is a significant cause of stable isotope offset in historical silk fabrics. • Different aging factors should be considered when tracing the origin of historic silk fabrics using stable isotope techniques. Understanding the degradation of silk fibers and tracing silk fabrics from archeological sites have always been challenging. The stable isotope technique provides the possibility to trace ancient textiles, especially for the controversial issue of the silk origin. Chinese historic silk fabrics from the Xia dynasty (about 4000 years ago), Warring States period (B.C. 475- B.C. 221), Tang dynasty (A.D. 618- A.D. 907), Southern Song period (A.D. 1127- A.D. 1279), Ming dynasty (A.D. 1368- A.D.1644), and Qing dynasty (A.D. 1636- A.D. 1912) as well as some artificially aged silk specimens have been examined by scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, and isotope ratio mass spectrometry (IRMS) to investigate their degradation for traceability and preservation. It has been found that the surface morphology and secondary structure of silk were destroyed in the degradation process. Under most aging modes, the silk fabrics were enriched with heavy stable isotopes after degradation. In the case of charring, the isotopic ratios of heavy hydrogen and oxygen isotopes showed different variation tendencies, which need to be further studied for better understanding. The results revealed that stable isotope ratios of silk fabrics are affected by different aging conditions. The degradation of silk fabrics is an important cause of stable isotope offset in historical silk fabrics. Overall, this study provides useful insights into the silk degradation mechanism and can serve as a useful reference for tracing the rich textile heritage. [ABSTRACT FROM AUTHOR]

Silica-alumina gel with micrometer-sized macropores and nanometer-sized mesopores has excellent advantages in humidity control properties. The macropores provide pathways for rapid H 2 O molecular transportation while the mesopores present a large surface area. An amorphous spherical silica-alumina beads material with a distinct bimodal pore structure was prepared by sol–gel reactions of tetraethoxysilane (TEOS) and aluminum nitrate in the presence of poly(ethyleneoxide) (PEO). It features high moisture adsorption capacity, super fast response to humidity changes, small equilibrium humidity control range and macroscopic spherical morphology. The appearance and structural properties of the material were investigated by digital camera, scanning electronic microscope (SEM) and thermal gravimetry and differential thermal analyses (TGA/DTA). The porosity features are further established by N 2 sorption experiments and pore size distribution analysis. The bonding characteristics and coordination features around aluminum have been studied using Fourier transform infrared spectroscopy (FTIR) and 27 Al magic angle spinning nuclear magnetic resonance ( 27 Al MAS NMR). The humidity control performance of the material at relative humidity was measured. The results revealed that the material kept a relative humidity in the range of 39.3–40.3%, 47.6–50.7% and 57.2–60.7%, respectively, under three different pre-treating conditions. And the humidity controlling equilibrium levels were all reached within 3 h. Therefore, the material could maintain a suitable relative humidity of 40–60% in enclosed spaces such as showcases in museums and galleries. [ABSTRACT FROM AUTHOR]

Mineral pigments have an important position in the traditional arts. To better protect cultural relics, the effects of high energy ball milling on the structure and properties of mineral pigments was investigated using malachite and turquoise as examples. Samples were characterized using a range of physical and spectroscopic measurements to determine the composition, morphology, and particle size of the samples. Chromaticity analysis was carried out using the L*a*b* color space model. The results showed that milling reduced the size and distribution of the mineral particles, reaching an amorphous state of high specific surface area. The crystalline state of the samples changed with milling time. Valency, atomic abundance, luminance, reflectivity, and chromaticity of the milled samples all showed various changes affected by crystallinity and grain size. Color change in malachite manifested mainly as a red-shift yellowish green with increasing milling time. Polycrystalline turquoise was bluish green and showed no color change during milling. The results from this study may provide the basis for improvements in antique pigment technology and assist with the selection of suitable pigments for the restoration of paintings. • Two natural greenish mineral pigments were treated with high energy ball milling. • The crystal form of part mineral pigments has changed after mechanochemical routes. • Mineral pigment color differences can be obtained by ball milling. • A method for precise colorimetric measurement of pigment powders. [ABSTRACT FROM AUTHOR]

The ultrasensitive detection of fibroin in unearthed silk relics has great significance for investigating the origin and transmission of silk. In this study, an anti-fibroin monoclonal antibody was successfully prepared through animal immunization. Next, a label-free electrochemical immunosensor was fabricated using layer-by-layer self-assembly technology, and an indirect enzyme-linked immunosorbent assay (ELISA) was proposed. The two methods exhibited excellent sensitivity and specificity in the detection of silk fibroin, while the immunosensor showed a wider quantitative detection range (0.1–100 ng mL−1) and a lower detection limit (0.051 ng mL−1) than ELISA (10–100 ng mL−1 and 8.71 ng mL−1). Furthermore, the performance of the immunosensor was superior in archaeological sample detection. Taking advantage of the well-prepared monoclonal antibody, the two proposed immunological assays demonstrate tremendous potential for the ultrasensitive detection of silk fibroin, which can make great contributions to exploring the origin and transmission routes of ancient silks. • Ultrasensitive detection for ancient silk has great significance to investigate the origin and transmission of silk. • A specific anti-fibroin monoclonal antibody was well designed and prepared. • A novel label-free electrochemical immunosensor and an indirect ELISA were proposed. • The immunosensor exhibited a low detection limit of 0.051 ng mL−1 for silk fibroin detection. • The performance of the immunosensor was excellent in qualitative and quantitative tests of ancient silks. [ABSTRACT FROM AUTHOR]