Applications of lignin in the agri-food industry

Of late, valorization of agri-food industrial by-products and their sustainable utilization is gaining much contemplation world-over. Globally, 'Zero Waste Concept' is promoted with main emphasis laid towards generation of minimal wastes and maximal utilization of plantbased agri-food raw materials. One of the wastes/by-products in the agri-food industry are the lignin, which occurs as lignocellulosic biomass. This biomass is deliberated to be an environmental pollutant as they offer resistance to natural biodegradation. Safe disposal of this biomass is often considered a major challenge, especially in low-income countries. Hence, the application of modern technologies to effectively reduce these types of wastes and maximize their potential use/applications is vital in the present day scenario. Nevertheless, in some of the high-income countries, attempts have been made to efficiently utilize lignin as a source of fuel, as a raw material in the paper industry, as a filler material in biopolymer based packaging and for producing bioethanol. However, as of today, agri-food industrial applications remains significantly underexplored. Chemically, lignin is heterogeneous, bio-polymeric, polyphenolic compound, which is present naturally in plants, providing mechanical strength and rigidity. Reports are available wherein purified lignin is established to possess therapeutic values; and are rich in antioxidant, anti-microbial, anti-carcinogenic, antidiabetic properties, etc. This chapter is divided into four sub-categories focusing on various technological aspects related to isolation and characterization of lignin; established uses of lignin; proved bioactivities and therapeutic potentials of lignin, and finally on identifying the existing research gaps followed by future recommendations for potential use from agri-food industrial wastes.Theme of this chapter is based on our ongoing project- Valortech, which has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 810630

Improved mechanical and thermal properties of spent coffee bean particulate reinforced poly(propylene carbonate) composites

Using biodegradable polypropylene carbonate (PPC) as the polymer matrix and 5 to 25 wt% content of spent coffee bean powder (SCBP) as filler, completely biodegradable composite films of PPC/SCBP were prepared. These composite films were characterized by polarized optical microscopy (POM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis, differential scanning calorimetry (DSC), and tensile tests. The POM images indicated the uniform distribution of the SCBP in the composites. The FTIR spectra indicated that the PPC structure was retained by the composite films. The XRD analysis found that the composite films had lower crystallinity than the PPC due to the presence of amorphous hemicellulose containing SCBP. A significant enhancement in thermal stability of the filler reinforced composite was noticed which was more than 30% of the PPC matrix due to the presence of polyphenols in SCBP. A maximum increase of 35% of tensile strength was observed with the addition of 20 wt% SCBP filled composite films. These biodegradable composite films with higher thermal stability and tensile strength can be considered for packaging applications

Differential diagnosis and clinical management of periapical radiopaque/hyperdense jaw lesions

Abstract Great attention has been given to the study of radiolucent periapical lesions to avert possible misdiagnosis of apical periodontitis associated with certain radiolucent non-endodontic lesions. However, there are a significant number of radiopaque lesions found in the periapical region, which could be equally relevant to endodontic practice. The diagnosis and management of these radiopaque/hyperdense lesions could be challenging to the endodontist. These bone alterations could be neoplastic, dysplastic or of metabolic origin. In the context of the more widespread use of cone-beam CT, a detailed review of radiopaque inflammatory and non-inflammatory lesions is timely and may aid clinicians perform a differential diagnosis of these lesions. Distinguishing between inflammatory and non-inflammatory lesions simplifies diagnosis and consequently aids in choosing the correct therapeutic regimen. This review discusses the literature regarding the clinical, radiographic, histological and management aspects of radiopaque/hyperdense lesions, and illustrates the differential diagnoses of these lesions