Latest Advances in Protein-Recovery Technologies from Agricultural Waste

Exploring the extraction, functional properties, and industrial applications of papain from Carica papaya

Papain a protease enzyme naturally present in the Carica papaya has gained significant interest across several industries due to its unique properties and versatility. The unique structure of papain imparts the functionality that assists in elucidating how papain enzyme works and making it beneficial for a variety of purposes. This review highlights recent advancements in papain extraction techniques to enhance production efficiency to meet market demand. The extraction of papain from the Carica papaya plant offers various advantages such as cost-effectiveness, biodegradability, safety, and the ability to withstand a wide range of pH and temperature conditions. Key findings reveal that non-conventional papain extraction techniques offer significant advantages in terms of efficiency, product quality, and environmental sustainability. Furthermore, papain treatment enhances the value of final products due to its anti-bacterial, anti-oxidant, and anti-obesity properties. The ability of papain to hydrolyze a wide range of proteins across various conditions makes it a suitable protease enzyme. While the study emphasizes the advantages of papain, the study also acknowledges limitations such as the continuous research and development to optimize extraction processes which will help unlock papain's potential and meet the growing demand. © 2024 Society of Chemical Industry.

Plant-based proteins from agro-industrial waste and by-products: Towards a more circular economy

There is a pressing need for affordable, abundant, and sustainable sources of proteins to address the rising nutrient demands of a growing global population. The food and agriculture sectors produce significant quantities of waste and by-products during the growing, harvesting, storing, transporting, and processing of raw materials. These waste and by-products can sometimes be converted into valuable protein-rich ingredients with excellent functional and nutritional attributes, thereby contributing to a more circular economy. This review critically assesses the potential for agro-industrial wastes and by-products to contribute to global protein requirements. Initially, we discuss the origins and molecular characteristics of plant proteins derived from agro-industrial waste and by-products. We then discuss the techno-functional attributes, extraction methods, and modification techniques that are applied to these plant proteins. Finally, challenges linked to the safety, allergenicity, anti-nutritional factors, digestibility, and sensory attributes of plant proteins derived from these sources are highlighted. The utilization of agro-industrial by-products and wastes as an economical, abundant, and sustainable protein source could contribute towards achieving the Sustainable Development Agenda's 2030 goal of a "zero hunger world", as well as mitigating fluctuations in food availability and prices, which have detrimental impacts on global food security and nutrition.

Agricultural wastes: a new promising source for phenylalanine ammonia-lyase as anticancer agent

The present study aims to investigate the physicochemical characteristics of phenylalanine ammonia-lyase (PAL) extracted from agricultural waste and its potential use as an anticancer agent in comparison to microbial PAL. We extracted and partially purified PAL from agricultural waste sources. We assessed the temperature and pH range of PAL and determined enzyme kinetics parameters including Michaelis constants (Km), maximum velocity (Vmax), and specificity constant values (Vmax/Km). Additionally, we examined the effects of different storage temperatures on PAL activity. In our analysis, we compared the efficacy of agricultural waste-derived PAL with PAL from Rhodotorula glutinis. The results demonstrated that PAL extracted from agricultural waste exhibited significantly higher specific activity (Vmax/Km) compared to its microbial counterpart. The agricultural waste-derived PAL displayed a stronger affinity for phenylalanine, as indicated by a lower Km value than the microbial PAL did. Furthermore, PAL from agricultural waste maintained activity across a broader temperature and pH range (15-75 °C, pH 5-11), in contrast to microbial PAL (20-60 °C, pH 5.5-10). Importantly, the PAL derived from agricultural waste exhibited superior stability, retaining over 90% of its activity after 6 months of storage at room temperature (25 °C), whereas microbial PAL lost more than 70% of its activity under similar storage conditions. In anticancer experiments against various cancer cell lines, agricultural waste-derived PAL demonstrated greater anticancer activity compared to microbial PAL. These findings suggest that PAL sourced from agricultural waste has the potential to be a safe and effective natural anticancer agent.

Genotoxic Assessment of Nutraceuticals Obtained from Agricultural Biowaste: Where Do We "AMES"?

Several pharmaceutical companies are nowadays considering the use of agri-food waste as alternative raw material for the extraction of bioactive compounds to include in nutraceuticals and food supplements. This recycling activity is encountering the support of authorities, which are alarmed by air, soil and water pollution generated by agricultural waste disposal. Waste reuse has several economic advantages: (i) its low cost; (ii) its abundance; (iii) the high content of bioactive molecule (antioxidants, minerals, fibers, fatty acids); as well as (iv) the financial support received by governments eager to promote eco-compatible and pollution-reducing practices. While nutraceuticals produced from biowaste are becoming popular, products that have been risk-assessed in terms of safety are quite rare. This despite waste biomass, in virtue of its chemical complexity, could, in many cases, mine the overall safety of the final nutraceutical product. In this review, we summarize the scientific results published on genotoxicity risk-assessment of bioactive compounds extracted from agricultural waste. The review depicts a scenario where the risk-assessment of biowaste derived products is still scarcely diffuse, but when available, it confirms the safety of these products, and lets us envisage their future inclusion in the list of botanicals allowed for formulation intended for human consumption.