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Abstract The market for microbial gums such as xanthan, gellan, dextran, and curdlan is continuously expanding, driven by their increasing application in various industries including petroleum, pharmaceuticals, cosmetics, and food, with the latter accounting for approximately 50% of global usage. To meet the growing demand and improve sustainability, there is a need to enhance production efficiency and reduce costs. This article addresses these issues by examining recent advancements and emerging trends in microbial gum production and application. By highlighting patented technologies and innovative approaches, the article aims to provide a comprehensive understanding of how the industry can achieve higher yields and economic viability. Despite being produced by different microorganisms, these gums are synthesized under similar conditions, such as pH, temperature, and medium composition. The purification or downstream processes for these gums are also comparable, primarily involving solvent precipitation, centrifugation for separation, and drying. Significant advances in gum production include genetic improvement of microbial strains to improve biopolymer performance. Additionally, alternative media are being explored, either by optimizing nutrient availability or deprivation, or by using agroindustrial by-products to reduce production costs. Engineering improvements are another strategy: bioreactor characteristics, fermentation conditions and modes of operation, and advances in downstream process are highlighted. Furthermore, the text explores emerging trends in the application of microbial gums in the food sector. Microbial gums applications are not limited to their traditional action as emulsifiers and stabilizers, but expands to new uses in biodegradable packaging films and as antioxidant and prebiotic food ingredient.

Weeds cause significant agricultural losses worldwide, and herbicides have traditionally been the main solution to this problem. However, the extensive use of herbicides has led to multiple cases of weed resistance, which could generate an increase in the application concentration and consequently a higher persistence in the environment, hindering natural degradation processes. Consequently, more environmentally friendly alternatives, such as microbial bioherbicides, have been sought. Although these bioherbicides are promising, their efficacy remains a challenge, as evidenced by their limited commercial and industrial production. This article reviews the current status of microbial-based bioherbicides and highlights the potential of cell-free metabolites to improve their efficacy and commercial attractiveness. Stirred tank bioreactors are identified as the most widely used for production-scale submerged fermentation. In addition, the use of alternative carbon and nitrogen sources, such as industrial waste, supports the circular economy. Furthermore, this article discusses the optimization of downstream processes using bioprospecting and in silico technologies to identify target metabolites, which leads to more precise and efficient production strategies. Bacterial bioherbicides, particularly those derived from Pseudomonas and Xanthomonas, and fungal bioherbicides from genera such as Alternaria, Colletotrichum, Trichoderma and Phoma, show significant potential. Nevertheless, limitations such as their restricted range of action, their persistence in the environment, and regulatory issues restrict their commercial availability. The utilization of cell-free microbial metabolites is proposed as a promising solution due to their simpler handling and application. In addition, modern technologies, including encapsulation and integrated management with chemical herbicides, are investigated to enhance the efficacy and sustainability of bioherbicides.

It is widely known that mushrooms present several properties with applications in the medicinal and pharmaceutical sectors, including antimicrobial, immunomodulatory, antioxidant, hypotensive, neuroprotective, and anti-inflammatory activities. This article aims to review examples of the bioactive metabolites responsible for those activities, such as polysaccharides, phenols and polyphenols, terpenes, peptides, alkaloids, and steroids, which are produced by several relevant mushroom species. It also discusses their production through solid-state fermentation and submerged fermentation, as well as the processes of obtention of mushroom bioactive extracts and considerations on their stability aiming industrial applications. In addition, the article examines the patent landscape surrounding mushroom-derived bioactives, shedding light on the intellectual property history and innovations driving this field forward. Examples of recently deposited patents in the field are highlighted, as well as the main depositors. China and the United States are the major depositor countries in this field (52% and 35% of patents, respectively), and the principal compounds on the patents are polysaccharides and alkaloids. The article also provides insights into the current market landscape, showcasing mushroom-derived products in the pharmaceutical field available to consumers. From dietary supplements to skincare formulations, the market offerings reflect the growing interest in harnessing the health benefits of mushroom bioactives.

Lutein, a yellow xanthophyll carotenoid, is increasingly recognized for its nutraceutical benefits, particularly in protecting the retina’s macula from age-related degeneration. Microalgae are a promising source of lutein, which can be a primary product or a coproduct in biorefineries. Certain microalgae exhibit lutein levels (up to 1.7%) surpassing those of common dietary sources like kale, spinach, and egg yolk (approximately 0.7–0.9%). Predominantly associated with photosystem II’s light-harvesting complex, lutein is crucial in photosynthesis and cellular defense. However, being quantitatively minor among cellular constituents, lutein necessitates specialized processing for efficient extraction. Although ubiquitous in microalgae, it is not as easily inducible as β-carotene and astaxanthin in Dunaliella salina and Haematococcus pluvialis, respectively. Currently, microalgal lutein production predominantly occurs at the bench scale, presenting challenges in scaling up. Factors like culture medium significantly influence biomass and lutein yields in industrial production, while downstream processing requires cost-effective, food-grade solvent extraction techniques. This review delves into contemporary methods and innovative progress in microalgal lutein production, emphasizing industrial-scale processes from biomass cultivation to final product formulation. A conceptual industrial process proposed in this review shows that two 10 m3 photobioreactors could produce 108 kg dry mass for Chlorella minutissima, which can be processed into approximately 616 g of lutein extract, or over 6000 capsules of finished nutraceutical daily. Despite lutein production via microalgae being in nascent stages at large scales, existing research provides a solid foundation for well-informed scale-up endeavors.

In recent years, concerns about a good-quality diet have increased. Food supplements such as prebiotics have great nutritional and health benefits. Within the diverse range of prebiotics, xylooligosaccharides (XOs) show high potential, presenting exceptional properties for the prevention of systemic disorders. XOs can be found in different natural sources; however, their production is limited. Lignocellulosic biomasses present a high potential as a source of raw material for the production of XOs, making the agro-industrial by-products the perfect candidates for production on an industrial scale. However, these biomasses require the application of physicochemical pretreatments to obtain XOs. Different pretreatment methodologies are discussed in terms of increasing the production of XOs and limiting the coproduction of toxic compounds. The advance in new technologies for XOs production could decrease their real cost (USD 25–50/kg) on an industrial scale and would increase the volume of market transactions in the prebiotic sector (USD 4.5 billion). In this sense, new patents and innovations are being strategically developed to expand the use of XOs as daily prebiotics.

Recycling bioresources is the only way to sustainably meet a growing world population’s food and energy needs. One of the ways to do so is by using agro-industry wastewater to cultivate microalgae. While the industrial production of microalgae requires large volumes of water, existing agro-industry processes generate large volumes of wastewater with eutrophicating nutrients and organic carbon that must be removed before recycling the water back into the environment. Coupling these two processes can benefit the flourishing microalgal industry, which requires water, and the agro-industry, which could gain extra revenue by converting a waste stream into a bioproduct. Microalgal biomass can be used to produce energy, nutritional biomass, and specialty products. However, there are challenges to establishing stable and circular processes, from microalgae selection and adaptation to pretreating and reclaiming energy from residues. This review discusses the potential of agro-industry residues for microalgal production, with a particular interest in the composition and the use of important primary (raw) and secondary (digestate) effluents generated in large volumes: sugarcane vinasse, palm oil mill effluent, cassava processing waster, abattoir wastewater, dairy processing wastewater, and aquaculture wastewater. It also overviews recent examples of microalgae production in residues and aspects of process integration and possible products, avoiding xenobiotics and heavy metal recycling. As virtually all agro-industries have boilers emitting CO2 that microalgae can use, and many industries could benefit from anaerobic digestion to reclaim energy from the effluents before microalgal cultivation, the use of gaseous effluents is also discussed in the text.