Silk fibroin (SF), a natural polymer produced by Bombyx mori silkworms, has been extensively explored to prepare porous scaffolds for tissue engineering applications. Here, we demonstrate, a scaffold made of SF, which exhibits compression modulus comparable to natural cancellous bone while retaining the appropriate porosities and interconnected pore architecture. The scaffolds also exhibit high resistance to in-vitro proteolytic degradation due to the dominant beta sheet conformation of the SF protein. Additionally, the scaffolds are prepared using a simple method of microparticle aggregation. We also demonstrate, for the first time, a method to prepare SF micro-particles using a Hexafluoroisopropanol-Methanol solvent-coagulant combination. SF microparticles obtained using this method are monodisperse, spherical, non-porous and extremely crystalline. These micro-particles have been further aggregated together to form a 3D scaffold. The aggregation is achieved by random packing of these microparticles and fusing them together using a dilute SF solution. Preliminary in-vitro cell culture and in-vivo implantation studies demonstrate that the scaffolds are biocompatible and they exhibit the appropriate early markers, making them promising candidates for bone regeneration.

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Xylanase is an important enzyme with potential application in the degradation of xylan component in the lignocellulosic biomass. There are very few reports on the production of cellulase free xylanases especially by yeast strains which have great potential in paper and pulp industry in removing the hemicellulose from the treated or untreated pulp. In this study, P. hubeiensis NCIM 3574 isolated in our laboratory produced significant levels of extracellular cellulase free xylanase (2480 IU/g DSS) in solid state fermentation (SSF) using wheat bran and xylan. It also produced high levels of β-xylosidase (198 IU/g DSS) when grown in SSF using ground nut oil cake and xylan. These highest activities were obtained when fermented Koji was extracted with 1% NaCl supplemented with 0.5% of Triton X-100. These are the highest activities reported so far from yeast strains in the available literature. The crude xylanase preparation of P. hubeiensis produced xylooligosaccharides (XOS) without xylose proving its potential for XOS production with no further requirement of downstream processing. The XOS as prebiotic show beneficial effect on gut microflora such as Lactobacilli and Bifidobacteria which suppress the activity of pathogenic organisms. This xylanase also has a potential application as a bio-bleaching agent in paper and pulp industry.

Mango (Mangifera indica) is a widely popular tropical fruit. When ripe, it is consumed either as fruit or juice, while raw mangoes are used in pickles, juice and curries. Apart from these, the seed kernels of ripe mangoes are in great demand by cosmetic and confectionary industries, while those from raw mangoes are used for medicinal purposes in traditional households of India. Although, the seed kernels have been used for various beneficial purposes, the inconsumable mango seed largely poses as a waste and biological pollutant. Therefore, it is pertinent to highlight the detailed composition and benefits of butter from various stages of mango kernel to highlight its commercial relevance. By using a combination of nuclear magnetic resonance spectroscopy and gas chromatography-mass spectroscopy based metabolic profiling, we studied the biochemical composition of different stages of mango kernel extract. We observed predominance of various types of fatty acids in all types of mango kernel with the ripe version showing the largest amount. The unripe versions though showed presences of a variety of aromats and antioxidants albeit at lower amounts. Our findings highlight that the unripe mango kernel extracts contains various aromats that have antimicrobial effects. India produces up to 23 million tonnes of mangoes every year and it has been estimated that it can produce up to 2.3 million tonnes of mango butter. Along with the fatty acids, these antimicrobials can be extracted as butter for commercial relevance thereby adding value to the seed kernel waste which otherwise pose as bio-pollutant.