Olive mill wastewater as a source of by-products promoting plant defense against microbial pathogens

Salvati, A.; Sciubba, F.; Diomaiuti, A.; Leone, G. P.; Pizzichini, D.; Bellincampi, D.; Pontiggia, D.

doi:10.1101/2024.06.13.598812

Home/Archive/bioRxiv

bioRxiv · 10.1101/2024.06.13.598812

Olive mill wastewater as a source of by-products promoting plant defense against microbial pathogens

Salvati, A.·Sciubba, F.·Diomaiuti, A.·Leone, G. P.·Pizzichini, D.·Bellincampi, D.·Pontiggia, D.

View original source ↗Export metadata ↓

Abstract

Olive oil is a core component of the Mediterranean diet known for its nutritional properties and health benefits. Olive industry is moving to novel extraction systems for higher oil yield and quality and for waste reduction, which is a relevant problem in the process due to its toxicity and high disposal costs. Multi-Phase Decanter (DMF) is a modern two-phase system performed without adding water during the process. Using DMF, a wet by-product indicated as pate and consisting of the fruit pulp and vegetation water (VW) is recovered. The pate has a high content of potentially bioactive molecules that may be exploited to promote plant resistance against microbial pathogens. In this work, to identify by/products of biological interest, the VW recovered from the pate by centrifugation was subjected to fractionation by tangential-flow membrane filtration (TFMF), combining microfiltration (MF) and ultrafiltration (UF). High-resolution NMR spectroscopy indicated the presence of bioactive molecules such as flavonoids, hydroxytyrosol and oleuropein with known antimicrobial activity. High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD) was performed to detect the presence of pectic oligosaccharides in the fractions, showing the enrichment, in the UF-concentrate fraction, of oligogalacturonides (OGs), well known for the ability to elicit defense responses and protect plants against pathogen infections. Arabidopsis thaliana plants treated with TFMF fractions displayed induction of defense responses and exhibited resistance against microbial pathogens without adverse effects on growth and fitness. This study shows that pate by-products can potentially be exploited in agriculture as sustainable plant phyto-protectant. Graphical abstract(image created with BioRender)

Source connections

Published article ↗

Explore related subjects

plant biology Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Salvati, A., Sciubba, F., Diomaiuti, A., Leone, G. P., Pizzichini, D., Bellincampi, D., Pontiggia, D.. 2024-06-16. Olive mill wastewater as a source of by-products promoting plant defense against microbial pathogens. https://doi.org/10.1101/2024.06.13.598812

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Large seed size accompanying GmSDP1 suppression is linked to cellular remodeling and phytohormone regulation

Soybean (Glycine max) seeds contain approximately 20% oil and 40% protein and are important for food, feed, and biofuel. Improving soybean productivity and seed quality requires optimizing carbon partitioning during seed development. Previously, seed-specific suppression of the lipase-encoding gene Sugar-Dependent 1 (SDP1) increased seed oil content by approximately 5% while slightly reducing raffinose family oligosaccharides without compromising protein content. Seed-specific SDP1 suppression also increased seed size by 18-25% without affecting seed number, resulting in greater seed biomass per plant. To determine the developmental basis of the increased seed size, we investigated the cellular and molecular mechanisms underlying this phenotype. Microscopy and biochemical analyses showed that larger seeds were associated with increased seed cell size and enhanced lignocellulosic cell wall accumulation. Temporal biochemical and transcriptomic analyses further revealed coordinated changes in hormone homeostasis, including altered levels of abscisic acid, 12-oxo-phytodienoic acid, and jasmonoyl-isoleucine, together with differential expression of F-box and RING/U-box family genes. The results indicate that the enhanced seed size resulting from SDP1 suppression is associated with coordinated changes in cellular development, cell wall accumulation, hormone homeostasis, and regulation of gene expression during seed development. Developmental and metabolic changes associated with the increased seed size phenotype support SDP1 manipulation as a potential strategy for improving soybean seed yield and quality.

plant biology↗

bioRxiv2026

Growth, yield, and quality of hot pepper (Capsicum annuum L.) as affected by the combined application of liquid bio-slurry and NPS fertilizer rates in Kucha, Gamo zone, south Ethiopia

Hot pepper (Capsicum annuum L.) is a key cash and nutritional crop in Ethiopia, yet its productivity remains constrained by inadequate and imbalanced soil nutrient management. Therefore, the field experiment was conducted in Kucha woreda, Gamo Zone, South Ethiopia, during the 2024/25 cropping season to investigate the effect of liquid bio-slurry and NPS fertilizer rates on growth, yield and quality of hot pepper. The experiment consisted of 16 treatments arranged in a factorial combination of four liquid bio-slurry (LBS) rates (0, 20, 40, and 60 m3 ha-1) and four NPS fertilizer rates (0, 75, 150, and 225 kg ha-1) using a randomized complete block design with three replications. All experimental data were collected following standard agronomic procedures and subjected to analysis of variance using GenStat statistical software (18th edition). The results revealed that both the main and interaction effects of liquid bio-slurry and NPS significantly (p < 0.01) influenced phenological, growth, yield, and quality parameters. The combined application of 150 kg ha-1 NPS and 60 m3 ha-1 LBS produced the highest marketable dry fruit yield (2.94 t ha-1) and total dry fruit yield (3.16 t ha-1), representing a 129.69% yield advantage over the control (1.28 t ha-1) in the case of marketable dry fruit yield. The findings demonstrate that integrated nutrient management using combined LBS and NPS fertilizers significantly enhanced the productivity and quality of hot pepper. Therefore, the application of 150 kg ha-1 NPS combined with 60 m3 ha-1 liquid bio-slurry is recommended for improved hot pepper production for the study area and similar agro-ecological conditions.

plant biology↗

bioRxiv2026

Higher stomatal density and smaller stomatal size associate with higher grain yield in winter wheat

In wheat (Triticum aestivum L.), flag leaf is crucial in determining grain-filling rate and final grain yield. Stomata, microscopic pores on plant surfaces, balance CO2 uptake and evaporative water loss; their numbers and aperture sizes depend on environmental factors. Previous studies have reported associations between stomatal traits and grain yield; mostly under controlled conditions. Our study aimed to investigate flag leaf stomatal anatomical and physiological traits, and their relationships with winter wheat grain yield under field conditions. We measured stomatal density and size, and stomatal conductance on adaxial and abaxial flag leaf surfaces in a three-year field study with twenty-five winter wheat varieties. Stomatal density ratio remained constant despite different stomatal densities occurring in different years, indicating coordinated adjustments of stomatal numbers between leaf surfaces in response to environmental conditions. Stomatal conductance ratios varied widely, indicating leaf-surface specific stomatal responses to environmental conditions. Grain yield was positively associated with stomatal density and negatively with stomatal size. Flag leaf removal reduced grain weight per spike and did not affect grain numbers per spike, unlike in spring wheat. Our field study provides valuable insights into the relationships between winter wheat stomatal traits and grain yield that can be used in breeding.

plant biology↗