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Biology subjects

Rubio-Moraga, A.

Publications and source records attributed to Rubio-Moraga, A..

4 recordsLinked to original sources

Solid-state fermentation of oyster mushroom by-products using Neurospora crassa: a sustainable approach for the development of novel meat analogues

Mushroom production generates large amounts of by-products, particularly stipes, which can represent up to half of the fruiting body biomass. Due to their similar composition to mushroom caps, these residues represent a promising substrate for the development of value-added foods. In this study, oyster mushroom stipes were used as a substrate for solid-state fermentation (SSF) with a Neurospora crassa strain isolated in Albacete to produce a novel meat analogue inspired by the oncom. Fermentation generated a cohesive matrix bound by hyphae that adopted the shape of the mold and exhibited a meat-like color, although with a softer texture. Nutritional analysis revealed a product with relatively low protein content but a complete amino acid profile, enriched in dietary fiber and containing unsaturated fatty acids. These results demonstrate that SSF with N. crassa provides a strategy to upcycle oyster mushroom by-products into fiber-rich meat analogues with potential applications in sustainable food systems.

microbiology↗

Valorization of mushroom by-products for sustainability: exploring antioxidant and prebiotic properties

Agaricus bisporus (white button mushroom), Pleurotus ostreatus (oyster mushroom), and Lentinula edodes (shiitake mushroom) are the most cultivated mushrooms in the Spanish region of Castilla-La Mancha. The increasing production of these mushrooms has created opportunities for sustainable utilization of their by-products such as undersized mushrooms, stalks, and stems. This study evaluated the antioxidant, prebiotic, and antimicrobial properties of aqueous, ethanolic and alkaline extracts derived from these by-products. Aqueous extracts from oyster mushroom, rich in glucose-polysaccharides (59.4{+/-}0.4% mushroom dw), promoted the growth and lactic acid production of the probiotic bacteria Lactocaseibacillus casei and Lactoplantibacillus plantarum. Shiitake extracts demonstrated antimicrobial activity against Pseudomonas aeruginosa, Escherichia coli and Salmonella enterica (Minimal inhibitory concentrations: 15, 7.5 and 7.5 mg/mL, respectively), and stimulated the growth of lactic acid bacteria at low concentrations (1.875 mg/mL) but inhibiting them at higher concentrations. Extracts from white button mushrooms exhibited the strongest antioxidant activity, particularly ethanolic extracts rich in phenolic compounds (0.015 mg Gallic acid/mg extract). These results highlight the potential of extracts of mushroom by-products as organic sources of antioxidants, antimicrobials, and prebiotics, creating new avenues for food product development. Reusing these by-products could encourage sustainability and assist the mushroom sector in implementing zero-waste and circular economy methods.

molecular biology↗

Crocetin and crocin production in plant and bacteria using a CCD4 enzyme from Nyctanthes arbor-tristis.

Crocins are hydrophilic crocetin esters that are arising interest as cosmetics and pharmaceuticals. Crocetin dialdehyde, the precursor of crocetin, derives from a C7-C8(C7-C8) cleavage of carotenoids in a few plant species including Crocus sativus or Nyctanthes arbor-tristis. We investigated the genome of N. arbor-tristis and identified an enzyme from the CCD4 subfamily catalyzing the cleavage of zeaxanthin to produce crocetin dialdehyde. This enzyme, NatCCD4.1, was used for the microbial production of crocetin dialdehyde in a two-phase culture system using direct extraction with n-dodecane, resulting in a titer of 109.2 {+/-} 3.23 mg/L, which is the highest crocetin dialdehyde yield reported in bacteria so far. Further, a viral vector was used to express NatCCD4.1 in Nicotiana benthamiana, triggering a crocin accumulation of 2.32 {+/-} 0.69 mg/g DW. Our results provide new insights into crocin biosynthesis and demonstrate that NatCCD4.1 is a valuable tool for improving crocetin and crocin production in heterologous systems.

plant biology↗

Exploring the Viral Landscape of Saffron through Metatranscriptomic Analysis

Saffron (Crocus sativus L.), a historically significant crop valued for its nutraceutical properties, has been poorly explored from a phytosanitary perspective. This study conducted a thorough examination of viruses affecting saffron samples from Spanish cultivars, using high-throughput sequencing alongside a systematic survey of transcriptomic datasets from Crocus sativus at the Sequence Read Archive. Our analysis unveiled a broad diversity and abundance, identifying 17 viruses across the 45 analyzed libraries, some of which were highly prevalent. This includes known saffron-infecting viruses and previously unreported ones. In addition, we discovered novel viruses from the Alphaflexiviridae, Betaflexiviridae, Potyviridae, Solemoviridae, and Geminiviridae families, with some present in libraries from various locations. These findings indicate that the saffron-associated virome is more complex than previously reported, emphasizing the potential of phytosanitary analysis to enhance saffron productivity.

plant biology↗