l-lactic acid production using the syrup obtained in biorefinery of carrot discards

Exploiting Self-Immobilized Fungi for Biovalorization of Oil Palm Sap to Organic Acids Through Repeated-Batch Fermentation

This study focused on utilizing agricultural waste, oil palm sap (OPS) as a sole nutrient source for organic acid production by self-immobilized fungi. Among the fungi cultured in OPS, Rhizopus oryzae TISTR 3336 was selected as it could form compact and adequate-size pellets (3-5 mm) and gave the highest total acid production yield of 0.31 ± 0.02 g/g-sugar under pH control. The optimal conditions were as follows: inoculum size of 106 spores/mL and shaking speed of 120 rpm. Using concentrated OPS gave higher final concentration of organic acids but reduced the production yield. The repeated-batch fermentation of OPS by self-immobilized fungi was successfully carried out for four cycles. The optimal initial sugar concentration was 40 g/L, giving the organic acid productions ranging of 19 to 35 g/L, with yields ranging of 0.47 to 0.87 g/g-sugar. This study has shown the efficient bioconversion of agricultural wastes into organic acids using self-immobilized fungi in the repeated-batch fermentation.

Methodological framework for supporting phytochemical bioprospecting re-search: A case study on carrot (Daucus carota L.) crop by-products

Carrots are among the most crucial and globally preferred vegetables, widely recognized for their importance as a source of phytonutrients, including phenolic compounds, carotenoids, polyacetylenes, and ascorbic acid. However, its production phase incurs substantial losses, estimated at 30 %; these discarded carrots typically find application in animal feed, composting material or organic waste. Therefore, this study aims to develop a methodological framework focusing on the application of a phytochemical bioprospecting process based on scientific surveillance; using carrot crop by-products as a foundational example. Advanced methodologies, such as bibliometric, scientometric, and patent analyses, supported by technological tools such as VOSviewer and Patent Inspiration, were employed. This involved the creation of scientific landscapes, trend maps and co-occurrence networks, intending to explore the potential of carrot crop by-products, their applicability in generating new knowledge, and their utilization in the industry. This approach facilitated the identification of emerging trends in scientific research, providing a comprehensive view of commercial and industrial areas of interest, with a focus on circular economic principles. Furthermore, the study emphasized the importance of bioprospecting, supported by these methodologies and technological tools, as a key factor in the research process on the potential uses of carrot crop by-products, which could extend to other matrices.

Development of a Strategy for L-Lactic Acid Production by Rhizopus oryzae Using Zizania latifolia Waste and Cane Molasses as Carbon Sources

As a biodegradable and renewable material, polylactic acid is considered a major environmentally friendly alternative to petrochemical plastics. Microbial fermentation is the traditional method for lactic acid production, but it is still too expensive to compete with the petrochemical industry. Agro-industrial wastes are generated from the food and agricultural industries and agricultural practices. The utilization of agro-industrial wastes is an important way to reduce costs, save energy and achieve sustainable development. The present study aimed to develop a method for the valorization of Zizania latifolia waste and cane molasses as carbon sources for L-lactic acid fermentation using Rhizopus oryzae LA-UN-1. The results showed that xylose derived from the acid hydrolysis of Z. latifolia waste was beneficial for cell growth, while glucose from the acid hydrolysis of Z. latifolia waste and mixed sugars (glucose and fructose) from the acid hydrolysis of cane molasses were suitable for the accumulation of lactic acid. Thus, a three-stage carbon source utilization strategy was developed, which markedly improved lactic acid production and productivity, respectively reaching 129.47 g/L and 1.51 g/L·h after 86 h of fermentation. This work demonstrates that inexpensive Z. latifolia waste and cane molasses can be suitable carbon sources for lactic acid production, offering an efficient utilization strategy for agro-industrial wastes.

Enzymatic synthesis of fructooligosaccharides: From carrot discards to prebiotic juice

A great volume of carrots is discarded daily worldwide because they do not meet the required shape and size standards. However, they have the same nutritional characteristics as those commercialized, and can be used in different food products. Carrot juice is an excellent matrix for the development of functional foods with prebiotic compounds, such as fructooligosaccharides (FOS). In this work, the production of FOS in situ in carrot juice was evaluated using a fructosyltransferase from Aspergillus niger, produced by solid-state fermentation on carrot bagasse. The enzyme was partially purified 12.5-fold with a total yield of 93 %, and specific activity of 59 U/mg of protein by Sephadex G-105 molecular exclusion chromatography. It was identified by nano LC-MS/MS as a β-fructofuranosidase with a 63.6 kDa MW and it allowed obtaining a FOS yield of 31.6 % in carrot juice. The result was a prebiotic juice with a final concentration of 32.4 mg/mL of FOS. Using the commercial enzyme Viscozyme L a higher yield of FOS (39.8 %) was obtained in carrot juice, corresponding to a total amount of FOS of 54.6 mg/mL. This circular economy scheme allowed the obtention of a functional juice, that may contribute to improve health of consumers.