Ecological linkages between biotechnologically relevant autochthonous microorganisms and phenolic compounds in sugar apple fruit (Annona squamosa L.).

Our study investigated the potential of Annona squamosa (L.) fruit as a reservoir of yeasts and lactic acid bacteria having biotechnological implications, and phenolics capable of modifying the ecology of microbial consortia. Only a single species of lactic acid bacteria (Enterococcus faecalis) was identified, while Annona fruit seemed to be a preferred niche for yeasts (Saccharomyces cerevisiae, Hanseniaspora uvarum), which were differentially distributed in the fruit. In order to identify ecological implications for inherent phenolics, the antimicrobial potential of water- and methanol/water-soluble extracts from peel and pulp was studied. Pulp extracts did not show any antimicrobial activity against the microbial indicators, while some Gram-positive bacteria (Staphylococcus aureus, Staphylococcus saprophyticus, Listeria monocytogenes, Bacillus megaterium) were susceptible to peel extracts. Among lactic acid bacteria used as indicators, only Lactococcus lactis and Weissella cibaria were inhibited. The chemical profiling of methanol/water-soluble phenolics from Annona peel reported a full panel of 41 phenolics, mainly procyanidins and catechin derivatives. The antimicrobial activity was associated to specific compounds (procyanidin dimer type B [isomer 1], rutin [isomer 2], catechin diglucopyranoside), in addition to unidentified catechin derivatives. E. faecalis, which was detected in the epiphytic microbiota, was well adapted to the phenolics from the peel. Peel phenolics had a growth-promoting effect toward the autochthonous yeasts S. cerevisiae and H. uvarum.

Date Seeds Flour Used as Value-Added Ingredient for Wheat Sourdough Bread: An Example of Sustainable Bio-Recycling.

Our study proposed date seeds flour (DSF) as an innovative ingredient for sourdough bread production through sustainable bio-recycling. We isolated autochthonous lactic acid bacteria and yeasts from DSF and DSF-derived doughs to build up a reservoir of strains from which to select starters ensuring rapid adaptation and high ecological fitness. The screening based on pro-technological criteria led to the formulation of a mixed starter consisting of Leuconostoc mesenteroides, Lactiplantibacillus plantarum, and Saccharomyces cerevisiae strains, which allowed obtaining a mature type I sourdough after consecutive refreshments, in which an aliquot of the durum wheat flour (DWF) was replaced by DSF. The resulting DSF sourdough and bread underwent an integrated characterization. Sourdough biotechnology was confirmed as a suitable procedure to improve some functional and sensory properties of DWF/DSF mixture formulation. The radical scavenging activity increased due to the consistent release of free phenolics. Perceived bitterness and astringency were considerably diminished, likely because of tannin degradation.

Design of potential probiotic yeast starters tailored for making a cornelian cherry (Cornus mas L.) functional beverage.

We carried out a step-by-step accurate procedure to design yeast starters with probiotic and technological traits to ferment cornelian cherry fruits puree (CP). Pichia kudriavzevii DCNa1 and Wickerhamomyces subpelliculosus DFNb6 were selected as binary starters due to their metabolic traits and low ethanol yield. Fermentation by selected starters positively affected the physical stability of CP. Depletion of loganic and cornuside acids during CP fermentation, leads us to speculate that yeasts might be involved in the conversion of iridoids to bioactive derivatives. Compared to unfermented CP, fermentation also affected the profile of CP volatiles, resulting in higher amount of alcohols and esters, and lower levels of aldehydes and alkanes. Viable cell number of selected yeasts in CP after 21 days of storage at 4 °C as well as after in vitro simulated digestion remained above the minimum dose recommended for a probiotic beverage. Under the in vitro gastrointestinal batch simulating the digestion process, we provided original evidence about the ability of yeasts conveyed by fermented CP to modulate the intestinal microbiota. We also faced some issues related to the yeasts physiology and the link between biofilm and cell viability that still deserve to be more in depth investigated.

The exploitation of cornelian cherry (Cornus mas L.) cultivars and genotypes from Montenegro as a source of natural bioactive compounds.

Cornelian cherry (CC) fruits a source of bioactive compounds that are still being underutilized. In this study, a comprehensive characterization of 11 Montenegrin CC local or introduced genotypes and cultivars collected in the wild or from organic orchards is provided. Their potential utilizations as natural antioxidants, colorants and organic food ingredients were exploited. CC fruits had high level of vitamin C (48-108 mg/100 g), malic acid (104-375 mg/100 g), and total polyphenols (158-591mgGAE/100 g). They also displayed high antioxidant activity based on DPPH (623-1903µmolTE/100 g), ABTS (441-1475µmolTE/100 g), and FRAP (1509-5954µmolFe2+/100 g) assays. UHPLC-PDA-HESI-MS/MS analyses were used to quantify the concentration of phenolic acids (7.69-19.87 mg/100 g), flavonoids (10.87-44.34 mg/100 g), anthocyanins (11.85-195.43 mg/100 g) and iridoids (129.07-341.20 mg/100 g). For each of this groups, the most abundant were caftaric acid (12.24 mg/100 g), quercetin 3-glucuronide (29.66 mg/100 g), cyanidin 3-O-galactoside (130.93 mg/100 g) and loganic acid (303.3 mg/100 g), respectively. PCA and cluster heatmap analysis highlighted potentials for further exploitation of local genotypes and cultivars through organic food processing and breeding program.

Lactic acid fermentation enriches the profile of biogenic fatty acid derivatives of avocado fruit (Persea americana Mill.).

This study investigated the capability of selected autochthonous lactic acid bacteria to enrich the portfolio of bioactive compounds of avocado fruit (Persea americana Mill.), with the perspective of producing dietary supplements or pharmaceutical preparations. Fermented avocado puree resulted in high levels of total free amino acids. Fermentation also led to a marked increase of antioxidant activity, with the highest levels found in water and hexane soluble extracts. Bio-converted phenolic compounds and fatty acids derivatives resulting from bacterial metabolism were likely responsible for the increased antioxidant activity. Fermentation caused the fortification of avocado puree with some hydroxy fatty acids, which deserved marked attention due to their health-promoting activities. Oleic and linoleic acids were highly metabolized by Lactobacillus plantarum AVEF17, leading to high levels of mono, di-, and tri-hydroxy-octadecenoic acids.

Fermented Portulaca oleracea L. Juice: A Novel Functional Beverage with Potential Ameliorating Effects on the Intestinal Inflammation and Epithelial Injury.

P. oleracea L. contains high level of nutrients and biologically active compounds. Recently, lactic fermentation has been proposed as a biotechnological option to enrich the profile of biogenic compounds of Portulaca oleracea L. puree. This study investigated the capability of fermentation by selected lactic acid bacteria to enhance the restoring features of Portulaca oleracea juice towards intestinal inflammation and epithelial injury. Lactic acid fermentation markedly increased the total antioxidant capacity of P. oleracea juice, preserved the inherent levels of vitamins C, A, and E, and increased the bioavailability of the level of vitamin B2 and that of phenolics. The effects of fermented P. oleracea juice on a Caco-2 cell line were investigated using an in vitro model closest to the in vivo conditions. Fermented P. oleracea juice strongly decreased the levels of pro-inflammatory mediators and reactive oxygen species. It also counteracted the disruption of the Caco-2 cell monolayers treated with the inflammatory stimulus. We used a diversified spectrum of lactic acid bacteria species, and some effects appeared to be strains- or species-specific. Fermentation with Lactobacillus kunkeei B7 ensured the best combination for the content of bioactive compounds and the ability to counteract the intestinal inflammation and epithelial injury.

Antimicrobial, antioxidant and sensory features of eugenol, carvacrol and trans-anethole in active packaging for organic ready-to-eat iceberg lettuce.

In this study, bio-based emitting sachets containing eugenol (EUG), carvacrol (CAR) and trans-anethole (ANT) were inserted into cellulose (CE) and polypropylene (PP) pillow packages of organic ready-to-eat (RTE) iceberg lettuce to investigate their functional features. EUG, CAR and ANT sachets in CE; and CAR in PP packages showed antimicrobial activities against coliforms (Δlog CFU g-1 of -1.38, -0.91, -0.93 and -0.93, respectively). EUG and ANT sachets in both packages reduced discoloration (ΔE of 9.5, 1.8, 9.4 and 5.6, respectively). ANT in both, and EUG only in PP packages induced biosynthesis of caffeoyl derivatives (CaTA, DiCaTA, DiCaQA), total phenolics and antioxidant activity (FRAP). Also, ANT and EUG in both packages improved overall freshness and odor. Principal component analysis separated ANT and EUG from CAR in both packages. The Pearson correlation confirmed that overall quality improvements were more pronounced by ANT inside the packages in comparison to EUG and CAR.

Biostimulants from food processing by-products: agronomic, quality and metabolic impacts on organic tomato (Solanum lycopersicum L.).

BACKGROUND: Biostimulants have recently gained increased attention due to their multiple benefits for sustainable agriculture. In this study, three food processing by-products - fennel processing residues (FPR), lemon processing residues (LPR) and brewer's spent grain (BSG) - were investigated as potential sources of biostimulants. Their aqueous extracts as individual and associated applications were assessed for their effects on agronomic, quality and metabolic performance of organic tomato in comparison to extract of humic substances (HS) and untreated control (CTRL). RESULTS: Only FPR extracts stimulated shoot growth and tomato dry matter content, whereas all candidates improved tomato yield. FPR and BSG increased fruit mineral content and BSG-FPR-LPR in combination enhanced titratable acidity. FPR-treated fruits had also 20% more vitamin C than CTRL, and higher phenol content was obtained in those of BSG-LPR. Fruit metabolomic profile showed the tendency of all extracts, except BSG-LPR, to increase tomato citric acid and to decrease ß-glucose and methanol concentrations. The analysis revealed accordingly the indispensable role of FPR in combined applications for inducing an HS-like response in fruits. CONCLUSION: The results were indicative of the biostimulant activity of these extracts and demonstrated them, particularly FPR, as promising candidates for enhancing plant productivity and fruit quality. © 2017 Society of Chemical Industry.

Exploitation of Leuconostoc mesenteroides strains to improve shelf life, rheological, sensory and functional features of prickly pear (Opuntia ficus-indica L.) fruit puree.

Strains of Leuconostoc mesenteroides were identified from raw prickly pear (Opuntia ficus-indica L.). Five autochthonous strains were selected based on the kinetics of growth and acidification on prickly pear fruit juice, and the capacity to synthesize exo-polysaccharides. All selected Leuc. mesenteroides strains showed an in vitro mucilage-degrading capability. A protocol for processing and storage of fermented prickly pear fruit puree (FP) was set up. Unstarted FP and chemically acidified FP were used as the controls. Starters grew and remained viable at elevated cell numbers during 21 days of storage at 4 °C. Contaminating Enterobacteriaceae and yeasts were found only in the controls. Viscosity and serum separation distinguished started FP compared to the controls. Colour parameters, browning index, sensory attributes, antimicrobial activity, vitamin C and betalains levels were positively affected by lactic acid fermentation. Increase of free radical scavenging activity in ethyl acetate soluble extract suggested an effect of selected strains on phenolic profiles. Started FP markedly inhibited the inflammatory status of Caco-2/TC7 cells, and also contributed to maintaining the integrity of tight junctions. Started FP scavenged the reactive oxygen species generated by H2O2 on Caco-2 cells. All selected strain variously affected the immunomodulatory activity towards anti- and pro-inflammatory cytokines.

Correction: Lactic Acid Fermentation of Cactus Cladodes (Opuntia ficus-indica L.) Generates Flavonoid Derivatives with Antioxidant and Anti-Inflammatory Properties.

[This corrects the article DOI: 10.1371/journal.pone.0152575.].

Lactic Acid Fermentation of Cactus Cladodes (Opuntia ficus-indica L.) Generates Flavonoid Derivatives with Antioxidant and Anti-Inflammatory Properties.

Cactus pear (Opuntia ficus-indica L.) is widely distributed in the arid and semi-arid regions throughout the world. In the last decades, the interest towards vegetative crop increased, and cladodes are exploited for nutraceutical and health-promoting properties. This study aimed at investigating the capacity of selected lactic acid bacteria to increase the antioxidant and anti-inflammatory properties of cactus cladodes pulp, with the perspective of producing a functional ingredient, dietary supplement or pharmaceutical preparation. Preliminarily, the antioxidant activity was determined through in vitro assays. Further, it was confirmed through ex vivo analysis on intestinal Caco-2/TC7 cells, and the profile of flavonoids was characterized. Cactus cladode pulp was fermented with lactic acid bacteria, which were previously selected from plant materials. Chemically acidified suspension, without bacterial inoculum and incubated under the same conditions, was used as the control. Lactobacillus plantarum CIL6, POM1 and 1MR20, Lactobacillus brevis POM2 and POM4, Lactobacillus rossiae 2LC8 and Pediococcus pentosaceus CILSWE5 were the best growing strains. Fermentation of cladode pulp with L. brevis POM2 and POM4 allowed the highest concentration of γ-amino butyric acid. Lactic acid fermentation had preservative effects (P<0.05) on the levels of vitamin C and carotenoids. Two flavonoid derivatives (kaemferol and isorhamnetin) were identified in the ethyl acetate extracts, which were considered to be the major compounds responsible for the increased radical scavenging activity. After inducing oxidative stress by IL-1ß, the increased antioxidant activity (P<0.05) of fermented cladode pulp was confirmed using Caco-2/TC7 cells. Fermented cladode pulp had also immune-modulatory effects towards Caco-2 cells. Compared to the control, fermented cladode pulp exhibited a significantly (P<0.05) higher inhibition of IL-8, TNFα and prostaglandins PGE2 synthesis. The highest functional effect was found using ethyl acetate extracts. In conclusion, fermentation, especially with L. plantarum strains and L. brevis POM4, enhanced the antioxidant and immune-modulation features of cladode pulp.

How the Organic Food System Supports Sustainable Diets and Translates These into Practice.

Organic production and consumption provide a delineated food system that can be explored for its potential contribution to sustainable diets. While organic agriculture improves the sustainability performance on the production side, critical reflections are made on how organic consumption patterns, understood as the practice of people consuming significant amounts of organic produce, may also be taken as an example for sustainable food consumption. The consumption patterns of regular organic consumers seem to be close to the sustainable diet concept of FAO. Certain organic-related measures might therefore be useful in the sustainability assessment of diets, e.g., organic production and organic consumption. Since diets play a central role in shaping food systems and food systems shape diets, the role of organic consumption emerges as an essential topic to be addressed. This role may be based on four important organic achievements: organic agriculture and food production has a definition, well-established principles, public standards, and useful metrics. By 2015, data for organic production and consumption are recorded annually from more than 160 countries, and regulations are in force in more than 80 countries or regions. The organic food system puts the land (agri-cultura) back into the diet; it is the land from which the diet in toto is shaped. Therefore, the organic food system provides essential components of a sustainable diet.

Organic cultivation of Triticum turgidum subsp. durum is reflected in the flour-sourdough fermentation-bread axis.

Triticum turgidum subsp. durum was grown according to four farming systems: conventional (CONV), organic with cow manure (OMAN) or green manure (OLEG), and without inputs (NOINPUT). Some chemical and technological characteristics differed between CONV and organic flours. As shown by two-dimensional electrophoresis (2-DE) analysis, OMAN and OLEG flours showed the highest number of gliadins, and OMAN flour also had the highest number of high-molecular-mass glutenins. Type I sourdoughs were prepared at the laboratory level through a back-slopping procedure, and the bacterial ecology during sourdough preparation was described by 16S rRNA gene pyrosequencing. Before fermentation, the dough made with CONV flour showed the highest bacterial diversity. Flours were variously contaminated by genera belonging to the Proteobacteria, Firmicutes, and Actinobacteria. Mature sourdoughs were completely and stably dominated by lactic acid bacteria. The diversity of Firmicutes was the highest for mature sourdoughs made with organic and, especially, NOINPUT flours. Beta diversity analysis based on the weighted UniFrac distance showed differences between doughs and sourdoughs. Those made with CONV flour were separated from the other with organic flours. Lactic acid bacterium microbiota structure was qualitatively confirmed through the culturing method. As shown by PCR-denaturing gradient gel electrophoresis (DGGE) analysis, yeasts belonging to the genera Saccharomyces, Candida, Kazachstania, and Rhodotorula occurred in all sourdoughs. Levels of bound phenolic acids and phytase and antioxidant activities differed depending on the farming system. Mature sourdoughs were used for bread making. Technological characteristics were superior in the breads made with organic sourdoughs. The farming system is another determinant affecting the sourdough microbiota. The organic cultivation of durum wheat was reflected along the flour-sourdough fermentation-bread axis.

Exploitation of Albanian wheat cultivars: characterization of the flours and lactic acid bacteria microbiota, and selection of starters for sourdough fermentation.

Six Albanian soft and durum wheat cultivars were characterized based on chemical and technological features, showing different attitudes for bread making. Gliadin and glutenin fractions were selectively extracted from flours, and subjected to two-dimensional electrophoresis. Linja 7 and LVS flours showed the best characteristics, and abundance of high molecular weight (HMW)-glutenins. Type I sourdoughs were prepared through back slopping procedure, and the lactic acid bacteria were typed and identified. Lactobacillus plantarum and Leuconostoc mesenteroides were the predominant species. Thirty-eight representative isolates were singly used for sourdough fermentation of soft and durum wheat Albanian flours and their selection was carried out based on growth and acidification, quotient of fermentation, and proteolytic activity. Two different pools of lactic acid bacteria were designed to ferment soft or durum wheat flours. Sourdough fermentation with mixed and selected starters positively affected the quotient of fermentation, concentration of free amino acids, profile of phenolic acids, and antioxidant and phytase activities. This study provided the basis to exploit the potential of wheat Albanian flours based on an integrated approach, which considered the characterization of the flours and the processing conditions.

Ptaquiloside in Pteridium aquilinum subsp. aquilinum and corresponding soils from the South of Italy: influence of physical and chemical features of soils on its occurrence.

The bracken fern Pteridium aquilinum (L.) Kuhn, one of the most common plant species on Earth, produces a wide range of secondary metabolites including the norsesquiterpene glucoside ptaquiloside (PTA). Several studies are present in literature about eco-toxicological aspects related to PTA, whereas results about the effect of growth conditions and soil properties on the production and mobility of PTA are sometimes conflicting and further investigations are needed. The aim of the present work is to investigate the occurrence and possible fate of PTA in soils showing different physical and chemical features, and collected in several areas of the South of Italy. The PTA content was determined in both soil and fern samples by GC-MS; both the extraction protocol and recovery were previously tested through incubation studies. Soils samples were also characterized from the physical and chemical points of view in order to correlate the possible influence of soil parameters on PTA production and occurrence. PTA concentration in P. aquilinum fern seemed to be significantly affected by the availability of nutrients (mainly P) and soil pH. At the same time, PTA concentration in soil samples was always undetectable, independent of the PTA concentration in the corresponding Pteridium samples and pedo-climatic conditions. This seems to suggest the degradation of the PTA by indigenous soil microbial community, whereas incubation studies underlined a certain affinity of PTA for both organic colloids and clay/silt particles.

Exploitation of the health-promoting and sensory properties of organic pomegranate (Punica granatum L.) juice through lactic acid fermentation.

Two strains (POM1 and C2) or LP09 of Lactobacillus plantarum, which were previously isolated from tomatoes and carrots, and another commercial strain of L. plantarum (LP09), were selected to singly ferment (30 °C for 120 h) pomegranate juice (PJ) under standardized protocol. PJs were further stored at 4 °C for 30 days. Filtered PJ, not added of starters (unstarted PJ), was used as the control. After fermentation, all starters grew to ca. 9.0 Log CFU/mL. Viable cells of strain LP09 sharply decreased during storage. The other two strains survived to ca. 7.0 and 8.0 Log CFU/mL. Lactic acid bacteria consumed glucose, fructose, malic acid, and branched chain and aromatic amino acids. The concentration of free fatty acids increased for all started PJs. Compared to unstarted PJ, color and browning indexes of fermented PJs were preferable. The concentration of total polyphenolic compounds and antioxidant activity were the highest for started PJs, with some differences that depended on the starter used. Fermentation increased the concentration of ellagic acid, and enhanced the antimicrobial activity. Fermented PJs scavenged the reactive oxygen species generated by H2O2 and modulated the synthesis of immune-mediators from peripheral blood mononuclear cells (PBMC). Unstarted and fermented PJs inhibited the growth of K562 tumor cells. The sensory attributes of fermented PJs were preferred. The fermentation of pomegranate juice would represent a novel technology option, which joins health-promoting, sensory and preservative features to exploit the potential of pomegranate fruits.

Effect of compost and manure amendments on zinc soil speciation, plant content, and translocation in an artificially contaminated soil.

The addition of organic matter in soil can modify the bioavailability of heavy metals. A greenhouse pot experiment was carried out using an edible plant species Eruca vesicaria L. Cavalieri grown on an artificially contaminated soil with Zn (665 mg kg(-1)). In this study, the effect of compost at 20 t ha(-1) (C20) and at 60 t ha(-1) (C60), manure at 10 t ha(-1) (M10) and at 30 t ha(-1) (M30), and chemical fertilizers (NPK) on Zn fate in a soil-plant system was evaluated. At the end of the experiment, the main growth parameters and Zn content in plants were determined. In addition, Zn speciation in the soil was assessed using the original Community Bureau of Reference sequential extraction and diethylene triamine pentaacetic acid extraction. Zinc, though an essential element for plant growth, caused toxicity effects in plants grown on control and manure treatments, while in the compost treatments, plants showed no visual toxicity symptoms. The concentrations of Zn in roots were similar for all treatments, while significant differences were observed for shoots. In fact, in the compost treatments, plants showed the lowest Zn concentration in shoots. Zinc speciation seems not to be affected by the applied treatments. Indeed, Zn plant content and translocation to shoots seems to be affected. Compost amendments significantly reduced Zn content and translocation in comparison to other treatments.

Nematicidal activity of (E,E)-2,4-decadienal and (E)-2-decenal from Ailanthus altissima against Meloidogyne javanica.

Methanol extracts of various plant parts of Ailanthus altissima were tested against the root knot nematode Meloidogyne javanica . Extracts of bark (ABE), wood (AWE), roots (ARE), and leaves (ALE) from A. altissima were investigated against freshly hatched second-stage juveniles (J(2)). AWE was the most active extract, with EC(50/3d) of 58.9 mg/L, while ALE, ARE, and ABE did not show nematicidal activity. The chemical composition of the extracts of A. altissima was determined by gas chromatography-mass spectrometry, and (E,E)-2,4-decadienal, (E)-2-undecenal, (E)-2-decenal, hexanal, nonanal, and furfural were the most prominent constituents. (E,E)-2,4-Decadienal, (E)-2-decenal, and furfural showed the highest nematicidal activity against M. javanica , with EC(50/1d) = 11.7, 20.43, and 21.79 mg/L, respectively, while the other compounds were inactive at the concentrations tested. The results obtained showed that AWE and its constituents (E,E)-2,4-decadienal and (E)-2-decenal could be considered as potent botanical nematicidal agents.

Chemical composition and in vitro activity of plant extracts from Ferula communis and Dittrichia viscosa against postharvest fungi.

F. communis and D. viscosa are perennial Mediterranean weeds that have been used for different therapeutic purposes in traditional pharmacopeia. Plant extracts were obtained from air dried D. viscosa young shoots (DvA) and F. communis aerial part (FcA) and roots (FcR) with n-hexane. The chemical compositions of the extracts were analyzed by HPLC-DAD, LC-MS (ESI) and LC-Q-TOF techniques. Two sesquiterpene lactones (inuviscolide, tomentosin) and three sesquiterpene acids (costic acid, hydroxycostic acid, ilicic acid) were identified from the D. viscosa extract, while in F. communis extracts three daucane sesquiterpenes (acetoxyferutinin, oxojaeskeanadioyl anisate, fertidin) and one coumarin (ferulenol) derivates were found. Biological activities of plant extracts were studied in in vitro experiments on the colonies and conidia of Botryotinia fuckeliana, Penicillium digitatum, P. expansum, Monilinia laxa, M. fructigena and Aspergillus spp. Extracts showed varying degree of antifungal activities on colony growth and conidia germination. The extract from FcA showed the least effect, while DvA extract had the strongest fungitoxic effects. FcR extract presented a fungitoxic effect on the colony growth, but it was not able to inhibit the conidia germination. These distinctions can be attributed to the differences in chemical composition of plant extracts.

Interactions between rotenone and humic acids by means of FT-IR and fluorescence spectroscopies.

The aim of this work was to ascertain, on a comparative basis, the compositional, structural and functional differences occurring between three humic acids (HAs), HA S1 (isolated from a Mediterranean brown soil), HA S2 (isolated from a Bavarian brown soil), and HA SR (a Suwannee River standard aquatic HA, purchased from IHSS), and to investigate the influence of their intrinsic properties on the types of binding mechanisms toward the pesticide rotenone. Original HAs and their corresponding HA-rotenone products, obtained by two different interaction protocols, were analyzed for elemental and functional group composition, and spectroscopic techniques, such as Fourier-transform infrared (FT IR) with Fourier self-deconvolution (FSD) and fluorescence both in the single-scan and in three-dimensional modes. The HA S1 sample appeared to be characterized by a greater aromaticity degree and lower polarity with respect to the HA S2, featured by a mixed aromatic/aliphatic character, whereas mainly aliphatic and acidic resulted the HA SR. The data obtained suggested that the low water-soluble, non-polar pesticide rotenone resulted preferentially adsorbed onto HAs by hydrophobic interaction, that was the prevailing mechanism in the order HA S1 > HA S2 >>> HA SR, whereas hydrogen bonds resulted predominant in the opposite order.