Biology subjects

Moreno-Gimenez, E.

Publications and source records attributed to Moreno-Gimenez, E..

3 recordsLinked to original sources

bioRxiv2025

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↗

bioRxiv2025

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↗

bioRxiv2022

GB_SynP: a modular dCas9-regulated synthetic promoter collection for fine-tuned recombinant gene expression in plants.

Programable transcriptional factors based on the CRISPR architecture are becoming commonly used in plants for endogenous gene regulation. In plants, a potent CRISPR tool for gene induction is the so-called dCasEV2.1 activation system, which has shown remarkable genome-wide specificity combined with a strong activation capacity. To explore the ability of dCasEV2.1 to act as a transactivator for orthogonal synthetic promoters, a collection of DNA parts was created (GB_SynP) for combinatorial synthetic promoter building. The collection includes (i) minimal promoter parts with the TATA box and 5UTR regions, (ii) proximal parts containing single or multiple copies of the target sequence for the gRNA, thus functioning as regulatory cis boxes, and (iii) sequence-randomized distal parts that ensure the adequate length of the resulting promoter. A total of 35 promoters were assembled using the GB_SynP collection, showing in all cases minimal background and predictable activation levels depending on the proximal parts used. GB_SynP was also employed in a combinatorial expression analysis of an auto-luminescence pathway in Nicotiana benthamiana, showing the value of this tool in extracting important biological information such as the determination of the limiting steps in an enzymatic pathway.

synthetic biology↗