We have previously discussed how proso millet husks are sometimes used for pillow fill. Foxtail millet husks would seem to be too small to be practical for such use. However, there is research on possible uses of this by-product - or actually of compounds in it - for other purposes. Those include bio-plastics, sound absorption materials, and antimicrobials. What are implications for potential uses of hulls of other small millets? ---- Akhil Babu, Abhirami R. Kumar, N.R. Amrutha, S. Madhurya, H.N. Punil Kumar, Jeevan Prasad Reddy, P.S. Keshava Murthy, Kokkarachedu Varaprasad, "Utilizing foxtail millet husk waste for sustainable new bioplastic composites with enhanced thermal stability and biodegradability," International Journal of Biological Macromolecules, Vol. 282, Part 5, 2024, https://doi.org/10.1016/j.ijbiomac.2024.137283 Abstract: Foxtail millet husk (FMH) is a byproduct that is not suitable for consumption and is often discarded as solid waste. However, it can be used as a raw material to develop novel bioplastic composites that transform agro-based leftovers into value-added goods. Herein, new bioplastic composites were developed from poly(lactic acid), poly(butylene adipate-co-terephthalate) and FMH based granules by Injection Molding. The required granules were generated via a solvent evaporation method. The resulted bioplastic composites were analyzed for their morphologies, mechanical properties, crystal structures, thermal stability, and melting and crystallization behaviors using various techniques, such as scanning electron microscopy, universal testing machine, X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. Expressly, chemical bonding between FMH fibers and poly(lactic acid)/poly(butylene adipate-co-terephthalate) PLA/PBAT was confirmed through Fourier Transform infrared spectroscopy analysis. The inclusion of FMH lowered the impact strength of the PLA/PBAT combination, which was confirmed by mechanical analysis. Morphological findings confirmed that the PLA/PBAT combination had FMH aggregation. DSC thermograph revealed negligible differences in glass transition and melting temperatures of PLA/PBAT blend with and without FMH. The thermogravimetry results exhibit that the FMH can improve bioplastic thermal stability. The addition of FMH improved the biodegradability of the PLA/PBAT bioplastic composites. Overall, FMH waste can be repurposed for bioplastic composites with enhanced thermal stability and biodegradability. This reduces solid waste from agricultural practices and creates eco-friendly products. Further research could lead to more sustainable alternatives. ---- Balasubramanian, Dhayalini, Senthil Rajendran, Bhuvanesh Srinivasan, and Nirmalakumari Angamuthu. 2020. "Elucidating the Sound Absorption Characteristics of Foxtail Millet (Setaria Italica) Husk" Materials 13, no. 22: 5126. https://doi.org/10.3390/ma13225126 Abstract: The current study deals with the analysis of sound absorption characteristics of foxtail millet husk powder. Noise is one the most persistent pollutants which has to be dealt seriously. Foxtail millet is a small seeded cereal cultivated across the world and its husk is less explored for its utilization in polymer composites. The husk is the outer protective covering of the seed, rich in silica and lingo-cellulose content making it suitable for sound insulation. The acoustic characterization is done for treated foxtail millet husk powder and polypropylene composite panels. The physical parameters like fiber mass content, density, and thickness of the composite panel were varied and their influence over sound absorption was mapped. The influence of porosity, airflow resistance, and tortuosity was also studied. The experimental result shows that 30-mm thick foxtail millet husk powder composite panel with 40% fiber mass content, 320 kg/m3 density showed promising sound absorption for sound frequency range above 1000 Hz. We achieved noise reduction coefficient (NRC) value of 0.54. In view to improve the performance of the panel in low-frequency range, we studied the efficiency of incorporating air gap and rigid backing material to the designed panel. We used foxtail millet husk powder panel of density 850 kg/m3 as rigid backing material with varying air gap thickness. Thus the composite of 320 kg/m3 density, 30-mm thick when provided with 35-mm air gap and backing material improved the composite’s performance in sound frequency range 250 Hz to 1000 Hz. The overall sound absorption performance was improved and the NRC value and average sound absorption coefficient (SAC) were increased to 0.7 and 0.63 respectively comparable with the commercial acoustic panels made out of the synthetic fibers. We have calculated the sound absorption coefficient values using Delany and Bezlay model (D&B model) and Johnson–Champoux–Allard model (JCA model) and compared them with the measured sound absorption values. ---- P.P. Darshitha, Athul Ravi, P. Lasya, Maneesha Menon, G. Sivasubramanian, K.M. Sreekanth, K.M. Sreedhar, "Foxtail millet husk as an innovative biomass in the preparation of silica-silver composite with antimicrobial and free radicle scavenging activities," Materials Today: Proceedings, Volume 66, Part 4, 2022, Pages 1830-1836, https://doi.org/10.1016/j.matpr.2022.05.285. Abstract: The crop, Foxtail millet is rich in dietary fibres and proteins with low glycaemic index. Hence it qualifies as a regular food in the Indian diet. This has raised the importance of the millet in increased agricultural production. The husk is a waste that can be effectively utilised. Opaline silica is present as phytoliths in the spikelet of the husk. This can be solubilized and precipitated out. In this work, opaline silica was converted to sodium silicate and the composite was precipitated at a pH of 4 using the sol–gel technique. The amount of silica was first quantified using XRF. The results obtained from XRF correlated well with those obtained from thermogravimetric analysis (TGA). The chemical groups are identified using IR spectroscopy. The phase identification of opaline silica and silver was done by powder X-ray diffractometry. The morphological characterization of the composite revealed an irregular structure with particle dimensions of 1.880 μm to 10.82 μm. EDX analysis showed the existence of silver and silicon. Prepared composite was tested for anti-microbial action against five pathogens and was found to be comparable with antibiotics ciprofloxacin and ampicillin. The composite also presented outstanding scavenging action against 5 radicals with BHT as a standard. Don Osborn, PhD (East Lansing, MI, US) North American Millets Alliance