Profile Of Compounds Research Articles

Different profiles of soil phosphorous compounds depending on tree species and availability of soil phosphorus in a tropical rainforest in French Guiana

BackgroundThe availability of soil phosphorus (P) often limits the productivities of wet tropical lowland forests. Little is known, however, about the metabolomic profile of different chemical P compounds with potentially different uses and about the cycling of P and their variability across space under different tree species in highly diverse tropical rainforests.ResultsWe hypothesised that the different strategies of the competing tree species to retranslocate, mineralise, mobilise, and take up P from the soil would promote distinct soil 31P profiles. We tested this hypothesis by performing a metabolomic analysis of the soils in two rainforests in French Guiana using 31P nuclear magnetic resonance (NMR). We analysed 31P NMR chemical shifts in soil solutions of model P compounds, including inorganic phosphates, orthophosphate mono- and diesters, phosphonates, and organic polyphosphates. The identity of the tree species (growing above the soil samples) explained > 53% of the total variance of the 31P NMR metabolomic profiles of the soils, suggesting species-specific ecological niches and/or species-specific interactions with the soil microbiome and soil trophic web structure and functionality determining the use and production of P compounds. Differences at regional and topographic levels also explained some part of the the total variance of the 31P NMR profiles, although less than the influence of the tree species. Multivariate analyses of soil 31P NMR metabolomics data indicated higher soil concentrations of P biomolecules involved in the active use of P (nucleic acids and molecules involved with energy and anabolism) in soils with lower concentrations of total soil P and higher concentrations of P-storing biomolecules in soils with higher concentrations of total P.ConclusionsThe results strongly suggest “niches” of soil P profiles associated with physical gradients, mostly topographic position, and with the specific distribution of species along this gradient, which is associated with species-specific strategies of soil P mineralisation, mobilisation, use, and uptake.

Evaluation of the Lipophilicity of Angularly Condensed Diquino- and Quinonaphthothiazines as Potential Candidates for New Drugs.

Lipophilicity is one of the most important properties of compounds required to estimate the absorption, distribution, and transport in biological systems, in addition to solubility, stability, and acid-base nature. It is crucial in predicting the ADME profile of bioactive compounds. The study assessed the usefulness of computational and chromatographic methods (thin-layer chromatography in a reversed-phase system, RP-TLC) for estimating the lipophilicity of 21 newly synthesized compounds belonging to diquinothiazines and quinonaphthiazines. In order to obtain reliable values of the relative lipophilicities of diquinothiazines and quinonaphthiazines, the partition coefficients obtained using different algorithms such as AlogPs, AClogP, AlogP, MLOGP, XLOGP2, XLOGP3, logP, and ClogP were compared with the chromatographic RM0 values of all the tested compounds measured by the experimental RP-TLC method (logPTLC). Additionally, logPTLC values were also correlated with other descriptors, as well as the predicted ADME and drug safety profiling parameters. The linear correlations of logPTLC values of the tested compounds with other calculated molecular descriptors such as molar refractivity, as well as ADME parameters (Caco-2 substrates, P-gp inhibitors, CYP2C19, and CYP3A4) generally show poor predictive power. Therefore, in silico ADME profiling can only be helpful at the initial step of designing these new candidates for drugs. The compliance of all discussed diquinothiazines and naphthoquinothiazines with the rules of Lipiński, Veber, and Egan suggests that the tested pentacyclic phenothiazine analogs have a chance to become therapeutic drugs, especially orally active drugs.

Storage Conditions for ‘Barton’ Pecan: Impact of Moisture Content and Temperature on Quality Maintenance and Volatile Compounds Profile

Storage Conditions for ‘Barton’ Pecan: Impact of Moisture Content and Temperature on Quality Maintenance and Volatile Compounds Profile

Scrutinizing the Antimicrobial and Antioxidant Potency of European Cranberry Bush (Viburnum opulus L.) Extracts

In the process of considering the documented health benefits of Viburnum opulus L. (V. opulus), including its anti-inflammatory and antioxidant activities, the present study was designed to qualitatively and quantitatively evaluate the biochemical profile and antimicrobial potency of four commercially available V. opulus extracts. These extracts were obtained from its flowers, bark, berries, and a mixture thereof by cold ultrasound-assisted extraction. An examination of the V. opulus extracts indicated a relative abundance of group compounds, such as phenolics, flavonoids, tannins, and anthocyanins, which are responsible for antioxidant activity (AOA). The widest range in all of the four group compounds was detected in the V. opulus extract sourced from berries, whereas the narrowest range was found in those obtained from flowers. The HPLC-ESI-TQ-MS/MS technique displayed relative fluctuations in the concentrations of individual amino acids (AAs) over the four V. opulus extracts. The prevalence of proline was marked in the flower-derived extract, which made up 63.3% of the total AAs, while aspartic and glutamic acids dominated in the berry-derived extract by contributing up to 29.2 and 24.4% to the total AA content, respectively. Profiling of the individual phenolic compounds disclosed the superiority of chlorogenic acid (up to 90.3%) in the berry and mixed extracts, as well as catechin (up to 57.7%) and neochlorogenic acid (11.1%) in the bark extract, which conveyed a remarkable contribution toward antimicrobial activity. The lowest content of individual phenolics was found in the flower extract. Owing to its substantially denser bioactive composition, the V. opulus berries and bark extracts exhibited markedly better AOA, which was pinpointed by three independent methods, i.e., DPPH•, FRAP, and ABTS•+, than those obtained from flowers or a mixture of V. opulus morphological parts. As part of the antimicrobial activity testing, the V. opulus extracts exhibited outstanding inhibitory activity and a homeopathic mode of action. The V. opulus extracts obtained from a mixture, bark, and berries were more active against 8 out of 19 selected test microorganisms at minimum inhibitory concentration (MIC) values that ranged from 0.24 to 0.49 µL mL−1. Overall, the extracts of V. opulus were found to be effective against Gram-positive and Gram-negative bacteria. However, their conceivable exploitation as functional or pharmaceutical ingredients must be further clarified within in vivo models.

Preliminary Investigation towards the Use of Infrared Technology for Raw Milk Treatment.

Infrared (IR) technology offers a promising solution for reducing microbiological loads in various food types while preserving their quality traits, such as flavour. However, research on IR's application in complex matrices is limited. Therefore, our preliminary study aimed to evaluate its effectiveness in sanitizing bovine raw milk. We assessed the bacterial count before and after IR treatment by comparing volatile organic compound profiles via headspace extraction and GC/MS analysis. Our findings showed that higher energy levels led to a greater bacterial reduction. IR85 was the most effective in reducing Coliforms and Enterobacteriaceae in non-homogenised samples, with a reduction ranging from -1.01 to >-2.99 and from -1.66 to -3.09 Log CFU/mL, respectively. IR60 and 70 showed no efficacy, while IR80 had intermediate but still satisfactory effect. IR85 notably affected volatile compounds, particularly increasing hexanal (from 0.08 to 4.21 ng g-1) and dimethyl sulphone (from 10.76 to 26.40 ng g-1), while IR80 better preserved the aroma profile. As a result, only IR80 was tested with homogenised raw milk, demonstrating significant bacterial reduction (from >2.39 to 3.06 Log CFU/mL for Coliforms and from 1.90 to >2.45 Log CFU/mL for Enterobacteriaceae) and maintaining the aroma profile quality.

Evaluation of Lippia scaberrima Sond. and Aspalathus linearis (Burm.f.) R. Dahlgren extracts on human CYP enzymes and gold nanoparticle synthesis: implications for drug metabolism and cytotoxicity

BackgroundMetabolism is an important component of the kinetic characteristics of herbal constituents, and it often determines the internal dose and concentration of these effective constituents at the target site. The metabolic profile of plant extracts and pure compounds need to be determined for any possible herb-drug metabolic interactions that might occur.MethodsVarious concentrations of the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with fermented and unfermented Aspalathus linearis extract were used to determine the inhibitory potential on placental, microsomal and recombinant human hepatic Cytochrome P450 enzymes. Furthermore, the study investigated the synthesis and characterization of gold nanoparticles from the ethanolic extract of Lippia scaberrima as a lead sample. Confirmation and characterization of the synthesized gold nanoparticles were conducted through various methods. Additionally, the cytotoxic properties of the ethanolic extract of Lippia scaberrima were compared with the gold nanoparticles synthesized from Lippia scaberrima using gum arabic as a capping agent.ResultsAll the samples showed varying levels of CYP inhibition. The most potent inhibition took place for CYP2C19 and CYP1B1 with 50% inhibitory concentration (IC50) values of less than 0.05 µg/L for the essential oil tested and IC50-values between 0.05 µg/L-1 µg/L for all the other combinations and extracts tested, respectively. For both CYP1A2 and CYP2D6 the IC50-values for the essential oil, the extracts and combinations were found in the range of 1 – 10 µg/L. The majority of the IC50 values found were higher than 10 µg/L and, therefore, were found to have no inhibition against the CYP enzymes tested.ConclusionTherefore, the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with Aspalathus linearis do not possess any clinically significant CYP interaction potential and may be further investigated for their adjuvant potential for use in the tuberculosis treatment regimen. Furthermore, it was shown that the cytotoxic potential of the Lippia scaberrima gold nanoparticles was reduced by twofold when compared to the ethanolic extract of Lippia scaberrima.

Conjugated linoleic acid‐enriched yoghurts development through homogenization: Study of fatty acids, volatile compounds profiles and physicochemical, rheological and sensory properties

Conjugated linoleic acid (CLA) is recognised for its health benefits: anticancer, antiinflamatory and antiatherogenic effects have been reported. CLA enriched yoghurts were developed through homogenization at two levels (H1 and H2 with 40 and 80 mg CLA/100 g of yoghurt, respectively) with a view to creating functional foods. CLA modified the volatile profile in a positive way: higher levels of diacetyl and ethyl butanoate and lower values of 2‐hexanone and 2‐heptanone, ethanol and certain acids were recorded. Yoghurts presented similar microstructure, but H1 showed higher consistency and lower pseudoplastic behaviour; meanwhile H2 presented less syneresis. All products had high acceptability.

Developing defined starter culture for reproducible profile of flavour compound in Chinese xiaoqu baijiu fermentation

Defined starter cultures, containing selected microbes could reduce the complexity of natural starter, are beneficial for controllable food fermentations. However, there are challenges in identifying key microbiota and constructing synthetic microbiota for traditional food fermentations. Here, we aimed to develop a defined starter culture for reproducible profile of flavour compounds, using Chinese Xiaoqu Baijiu fermentation as a case. We classified all microbes into 4 modules using weighted correlation network analysis. Module 3 presented significant correlations with flavour compounds (P < 0.05) and the highest gene abundance related with flavour compound production. 13 dominant species in module 3 were selected for mixed culture fermentation, and each species was individually deleted to analyse the effect on flavour compound production. Ten species, presenting significant effects (P < 0.05) on flavour compound production, were selected for developing the starter culture, including Rhizopus oryzae, Rhizopus microsporus, Saccharomyces cerevisiae, Pichia kudriavzevii, Wickerhamomyces anomalus, Lactobacillus acetotolerans, Levilactobacillus brevis, Weissella paramesenteroides, Pediococcus acidilactici, and Leuconostoc pseudomesenteroides. After optimising the structure of the starter culture, the profile similarity of flavour compounds produced by the starter culture reached 81.88% with that by the natural starter. This work indicated feasibility of reproducible profile of flavour compounds with defined starter culture for food fermentations.

UHPLC-HRMS-based profiling and simultaneous quantification of the hydrophilic phenolic compounds from the aerial parts of Hypericum aucheri Jaub. &amp;amp; Spach (Hypericaceae)

A validated UHPLC-HRMS method was developed to identify and quantify polar phenolic metabolites in the EtOH extract from H. aucheri Jaub. &amp; Spach’s aerial parts. The external standards, chlorogenic acid, mangiferin, and hyperoside were selected in this analysis. Forty-four compounds, encompassing hydroxybenzoic and hydroxycinnamic acids derivatives, benzophenones, catechins, xanthones, flavonols, biflavones, and chromones were detected and quantified in the aerial parts of the titled plant. Pentahydroxyxanthone-C-glycoside 15, maclurin-O-(benzoyl)-hexoside 37, norathyriol-O-(benzoyl)-hexosides 38 and 42 were suggested to be new natural compounds, while maclurin-O-hexoside 2 was reported for the first time for Hypericum genus. Additionally, more than 22 secondary metabolites, including benzophenones, hydroxycinnamic acid derivatives, catechins, and a chromone, were identified for the first time in H. aucheri. The amounts of the detected metabolites were calculated relative to external standards. The dominant polar phenolic constituents were chlorogenic acid (11.55 mg/g D.W.) and mangiferin (9.13 mg/g D.W.).

Industrial-produced lemon nanovesicles ameliorate experimental colitis-associated damages in rats via the activation of anti-inflammatory and antioxidant responses and microbiota modification

Plant-derived nanovesicles (PDNVs) have recently emerged as natural delivery systems of biofunctional compounds toward mammalian cells. Considering their already described composition, anti-inflammatory properties, stability, and low toxicity, PDNVs offer a promising path for developing new preventive strategies for several inflammatory diseases, among which the inflammatory bowel disease (IBD). In this study, we explore the protective effects of industrially produced lemon vesicles (iLNVs) in a rat model of IBD. Characterization of iLNVs reveals the presence of small particles less than 200 nm in size and a profile of bioactive compounds enriched in flavonoids and organic acids with known beneficial properties. In vitro studies on human macrophages confirm the safety and anti-inflammatory effects of iLNVs, as evidenced by the reduced expression of pro-inflammatory cytokines and increased levels of anti-inflammatory markers. As evidenced by in vivo experiments, pre-treatment with iLNVs significantly alleviates symptoms and histological features in 2,4 dinitrobenzensulfuric acid (DNBS)-induced colitis in rats. Molecular pathway analysis reveals modulation of NF-κB and Nrf2, indicating anti-inflammatory and antioxidant effects. Finally, iLNVs affects gut microbiota composition, improving the consistent colitis-related alterations. Overall, we demonstrated the protective role of industrially produced lemon nanovesicles against colitis and emphasized their potential in managing IBD through multifaceted mechanisms.

Modulating peppermint oil flavor release properties of emulsion-filled protein gels: Impact of cross-linking method and matrix composition

For some food applications, it is desirable to control the flavor release profiles of volatile flavor compounds. In this study, the effects of crosslinking method and protein composition on the flavor release properties of emulsion-filled protein hydrogels were explored, using peppermint essential oil as a model volatile compound. Emulsion-filled protein gels with different properties were prepared using different crosslinking methods and gelatin concentrations. Flavor release from the emulsion gels was then monitored using an electronic nose, gas chromatography-mass spectrometry (GC–MS), and sensory evaluation. Enzyme-crosslinked gels had greater hardness and storage modulus than heat-crosslinked ones. The hardness and storage modulus of the gels increased with increasing gelatin concentration. For similar gel compositions, flavor release and sensory perception was faster from the heat-crosslinked gels than the enzyme-crosslinked ones. For the same crosslinking method, flavor release and perception decreased with increasing gelatin concentration, which was attributed to retardation of flavor diffusion through the hydrogel matrix. Overall, this study shows that the release of hydrophobic aromatic substances can be modulated by controlling the composition and crosslinking of protein hydrogels, which may be useful for certain food applications.

Chemical profiling and in-silico prediction of bioactive compounds from Wrightia tinctoria R.Br to treat psoriatic arthritis

Psoriatic arthritis (PsA) is an autoimmune-mediated inflammatory skin condition with limited remedies. This study mainly focuses on exploring the therapeutic efficiencies of Wrightia tinctoria R.Br (WT) for the treatment of PsA. Quantification and chemical profiling for the WT leaves were tested using standard in vitro biochemical assays. The ethanol extract of WT has been found to have high amounts of phenolic (24.48±0.03mg/mL) and flavonoid (29.2±0.16mg/mL) contents when compared to other solvent fractions. We also conducted a series of in vitro assays, including DPPH, nitric oxide radical scavenging, and protein denaturation inhibition assays, to assess the overall antioxidant and anti-inflammatory capabilities of WT extracts. The GC-MS analysis of WT leaf extract displayed Lup-20(29)-en-3-yl acetate, 24-Norursa-3,12-diene, and 3-O-Methyl-D-fructose as major bioactive compounds. The screened bioactive compounds, via pharmacokinetic and pharmacodynamic analysis, were subjected to density functional theory for energy minimization. Further, the hub targets of PsA were filtered from the Open Target online database to study the drug-target interaction. CD4, CXCL12, KLRD1, MMP9, and SERPINA1 were found to be the primary targets, which have a central role in the disease pathway. Selected disease targets were then docked with the energy-minimized bioactive compounds from WT leaves using PyRx. The results suggest that the ethanolic leaf extract from WT leaves could alter the progression of pathway mediators and effectively manage the PsA.

Synthesis and biological (in vitro and in silico) screening of the 4-aryl-fused pyranopyrazole derivatives as enzyme (α-amylase, α-glucosidase, acetylcholinesterase & proteinase) inhibitors with anti-oxidant and cytotoxic activities

The development of single compound targeting dual/multiple proteins is an efficient approach to avoid the combined drug administration. Herein, based on the modification of the previously reported lead compound A, we synthesized a new series of dihydropyranopyrazolone 7a-g and dihydro-pyrazolopyranopyrimidin-5-amine 8. The compounds were evaluated for their inhibitory in vitro enzymatic potential against α-amylase, α-glucosidase, acetylcholinesterase & proteinase. Also, the in vitro antioxidant evaluation and cytotoxicity assays were performed for all the final compounds. Interestingly, compound 8 possessed moderate activity against α-amylase (25.38 %) and α-glucosidase (29.37 %) compared to acarbose (75.43 % and 52.79 %, respectively). On the other hand, compound 7f showed a moderate anti-cholinesterase activity (46 ± 0.03 % inhibition) compared to donepezil used as a reference standard drug (67.28 ± 0.61 %). Compound 7d exhibited a moderate anti-arthritic activity (proteinase denaturation (42.21 ± 0.04 %), inhibition of proteinase (38.09 ± 0.04 %)) compared to diclofenac sodium used as a reference (47.93 ± 0.01, 44.96 ± 0.02, respectively). Compound 8 exhibited significant antioxidant activity in TAC assay and increased ABTS scavenging activity. Compounds 7 and derivative 8 exhibited reduced or no toxicity against the normal skin fibroblast thus confirming their safety at least in vitro. The in silico ADMET (absorption, distribution, metabolism, elimination and toxicity) profile of all final compounds implied their acceptability as oral bioavailable drug-likeness property. The anti-hyperglycemic activity was emphasized by the molecular docking of compound 8 showing good interactions in the acarbose binding site of both α-amylase and α-glucosidase enzymes. This study presents the dihydropyrazolopyranopyrimidin-5-amine derivative (compound 8) as a promising scaffold for future modification to design and develop derivatives with increased inhibitory effect against α-amylase and α-glucosidase for the management of type 2 diabetes mellitus (T2DM).

Emission factors and source profiles of volatile organic compounds from the automobile manufacturing industry

Controlling volatile organic compounds (VOCs) emitted from the automobile manufacturing industry requires establishing VOCs emission factors (EFs) and source profiles refinedly. In this study, 41 samples involved 32 VOCs discharge links were collected from three factories. The EFs and VOCs source profiles were estimated by the material balance method and weighted average method, respectively. The ozone formation potential (OFP) of the 110 VOCs species were calculated by the maximum incremental reactivity (MIR). According to estimations, the ranges of EFs were 0.23–1.66 kg VOCs/SUV car and 2.14–14.86 g VOCs/m2 painted area. EFs of six materials were firstly estimated, which are electrophoretic primer (152.31 ± 97.39 g VOCs/SUV car, 0.97 ± 0.38 g VOCs/m2 painted area), sealant (48.39 ± 26.20 g VOCs/SUV car, 0.46 ± 0.25 g VOCs/m2 painted area), floating coat (87.40 ± 75.63 g VOCs/SUV car, 0.86 ± 0.74 g VOCs/m2 painted area), colored paint (127.24 ± 168.24 g VOCs/SUV car, 1.25 ± 1.66 g VOCs/m2 painted area), varnish (205.46 ± 218.14 g VOCs/SUV car, 2.01 ± 2.15 g VOCs/m2 painted area), and cleaning solvent (328.54 ± 404.94 g VOCs/SUV car, 3.23 ± 3.98 g VOCs/m2 painted area). OVOCs (37.40–51.60 %) and aromatics (36.40–37.00 %) were the dominant components. n-Butyl acetate, 1,2,4-trimethylbenzene, undecane, n-hexanal, acetone, 1,2,3-trimethylbenzene, 1,3,5 -trimethylbenzene, m/p/o-xylene, 3-ethylbenzene, and 4-ethylbenzene were the major VOCs species, accounting for 68 % of total VOCs in the automobile manufacturing industry. Considering the OFP values of species, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, 1,2,3-trimethylbenzene, m/p-xylene, acetaldehyde, methyl ethyl ketone are the key active species that should be prioritized for control.

Unveiling the Hidden Impact: How Biodegradable Microplastics Influence CO2 and CH4 Emissions and Volatile Organic Compounds (VOCs) Profiles in Soil Ecosystems

Biodegradable plastics promise eco-friendliness, yet their transformation into microplastics (bio-MPs) raises environmental alarms. However, how those bio-MPs affect the greenhouse gases (GHGs) and volatile organic compounds (VOCs) in soil ecosystems remains largely unexplored. Here, we investigated the effects of diverse bio-MPs (PBAT, PBS, and PLA) on GHGs and VOCs emission in typical paddy or upland soils. We monitored the carbon dioxide (CO2) and methane (CH4) fluxes in-situ using the self-developed portable optical gas sensor and analyzed VOC profiles using a proton-transfer reaction mass spectrometer (PTR-MS). Our study has revealed that, despite their biodegradable nature, bio-MPs do not always promote soil GHG emissions as previously thought. Specifically, PBAT and PLA significantly increased CO2 and CH4 emissions up to 1.9–7.5 and 115.9–178.5 fold, respectively, compared to the control group. While PBS exhibited the opposite trend, causing a decrease of up to 39.9% for CO2 and up to 39.9% for CH4. In addition, different types of bio-MPs triggered distinct soil VOC emission patterns. According to the Mann-Whitney U-test and Partial Least Squares Discriminant Analysis (PLS-DA), a recognizable VOC pattern associated with different bio-MPs was revealed. This study claims the necessity of considering polymer-specific responses when assessing the environmental impact of Bio-MPs, and providing insights into their implications for climate change. Environmental ImplicationsThis study aims to investigate the often-overlooked consequences of Biodegradable plastics (BPs) on soil ecosystems, with a specific emphasis on the effects of microplastics generated from different BPs (bio-MPs) on greenhouse gas (GHG) emissions and volatile organic compounds (VOCs). We have identified distinct GHG and VOC emission patterns linked to different bio-MPs, thus highlighting the potential dangers of these seemingly innocuous alternatives, and providing valuable insights into their implications for climate change. Our findings emphasize the necessity for a more comprehensive evaluation of the ecological impact of BPs, which is crucial for making well-informed environmental policies and sustainable material choices.

Flavor profile and quality of strawberry wine are improved through sequential fermentation with indigenous non-Saccharomyces yeasts and Saccharomyces cerevisiae

In order to explore novel producing strategies for enhancing flavor compounds profile and quality of strawberry wine, we studied the effect of the sequential fermentation of two selected indigenous non-Saccharomyces yeasts (Hanseniaspora uvarum PGR9 and Kurtzmaniella quercitrusa PGT1) and Saccharomyces cerevisiae CGMCC 2.3854 on the fermentation kinetics, physicochemical characteristics, organic acids, antioxidant activity, volatile compositions, and sensory properties. Results showed that the ethanol content produced by the fermentation of Kq-Sc was significantly lower than that of Sc pure fermentation. In addition, the total volatile compounds concentration produced by the fermentation of Hu-Sc (16.2 ± 3.6 mg/L) and Kq-Sc (19.5 ± 3.1 mg/L) were significantly higher than that of Sc pure fermentation (13.8 ± 2.0 mg/L). In particular, the Kq-Sc strawberry wine presented the highest number of relative odor-active compounds (rOAV ≥1). Moreover, strawberry wine fermented by Hu+Kq-Sc showed the highest ABTS free radical scavenging ability and the highest overall sensory qualities. The results indicated that the K. quercitrusa PGT1 strain could be an alternative yeast for producing strawberry wine, and the sequential fermentations of Kq-Sc and Hu+Kq-Sc were effective strategies for improving the flavor and quality of strawberry wine.

Volatile Metabolites to Assess the Onset of Chilling Injury in Fresh-Cut Nectarines.

Fresh-cut processing is a good strategy to enhance the commercialization of peaches and nectarines, which easily deteriorate during low-temperature storage mostly due to the occurrence of chilling injury. Although several studies have been performed to improve the shelf-life of fresh-cut stone fruit, the achievement of high-quality fresh-cut peaches and nectarines still constitutes a challenge. The present study aimed to gain insights into the evolution of the postharvest quality of fresh-cut nectarines (Prunus persica L. Batsch) Big Bang, cold-stored at two different storage temperatures (4 and 8 °C) for up to 10 days. Several aspects influencing the quality traits (sensory and postharvest quality parameters; the profile of phenolic and volatile organic compounds (VOCs)) were explored to predict the marketable life of the fresh-cut nectarines. The respiration rate was higher in samples stored at 4 °C, while the browning process was more evident in fruit stored at 8 °C. Partial Least Squares Regression performed on VOCs showed that samples stored at 4 °C and 8 °C presented a different time evolution during the experiment and the trajectories depended on the interaction between time and temperature. Moreover, Multiple Linear Regression analysis discovered that the 17 VOCs affected by the storage conditions seemed to suggest that no chilling injury was detected for nectarines Big Bang. In conclusion, this approach could also be used with other nectarine cultivars and/or different stone fruits.

New Genetic Determinants for qPCR Identification and the Enumeration of Selected Lactic Acid Bacteria in Raw-Milk Cheese.

Lactic acid bacteria (LAB) play an important role in the ripening of cheeses and contribute to the development of the desired profile of aroma and flavor compounds. Therefore, it is very important to monitor the dynamics of bacterial proliferation in order to obtain an accurate and reliable number of their cells at each stage of cheese ripening. This work aimed to identify and conduct a quantitative assessment of the selected species of autochthonous lactic acid bacteria from raw cow's milk cheese by the development of primers and probe pairs based on the uniqueness of the genetic determinants with which the target microorganisms can be identified. For that purpose, we applied real-time quantitative PCR (qPCR) protocols to quantify Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Lactococcus lactis subsp. cremoris cells in cheese directly after production and over three-month and six-month ripening periods. While L. lactis subsp. cremoris shows good acidification ability and the ability to produce antimicrobial compounds, L. delbrueckii subsp. bulgaricus has good proteolytic ability and produces exo-polysaccharides, and S. thermophilus takes part in the formation of the diacetyl flavor compound by metabolizing citrate to develop aroma, they all play an important role in the cheese ripening. The proposed qPCR protocols are very sensitive and reliable methods for a precise enumeration of L. delbrueckii subsp. bulgaricus, S. thermophilus, and L. lactis subsp. cremoris in cheese samples.

Influence of the Different Maturation Conditions of Cocoa Beans on the Chemical Profile of Craft Chocolates.

Cocoa beans (Theobroma cacao L.) can be used for craft chocolate production, which arouses consumer interest due to their perceived better quality. This study aimed to evaluate the chemical profile of 80% artisanal chocolate samples produced with cocoa beans subjected to different maturation conditions. In the first maturation process, beans were matured under no-oxygen conditions, and in the second, the toasted beans were matured in oak barrels. The volatile compounds of the chocolate samples were extracted by the solid-phase microextraction method in headspace mode and analyzed by gas chromatography/mass spectrometer. The non-volatile compounds were extracted with methanol and analyzed through paper spray mass spectrometry. Overall, 35 volatile compounds belonging to different chemical classes (acids, alcohols, aldehydes, ketones, esters, and pyrazines) were identified, such as propanoic acid and butane-2,3-diol. In addition, 37 non-volatile compounds, such as procyanidin A pentoside and soyasaponin B, were listed. Tannins, flavonoids, and phenylpropanoids were the main chemical classes observed, varying between the two samples analyzed. Therefore, it was possible to verify that maturation conditions affected the metabolomic profile of the 80% artisanal chocolate samples, being able to influence the sensory characteristics and bioactive compounds profile. Given these results, the sensory evaluation of these chocolates is suggested as the next step.

Upregulated synthesis and production of bioactive compounds in Lotus arabicus L. by in vitro feeding with dried powder of date palm seeds

BackgroundPlants are considered the primary source of many principal bioactive compounds that have been utilized in a wide range of applications including the pharmaceutical and biotechnological industries. Therefore, there is an imperative need to modulate the production of natural bioactive components. The present study aimed to determine the importance of dried and pulverized date palm seeds (DPS) as a natural elicitor for the synthesis of secondary metabolites in Lotus arabicus L.ResultsThe presence of various antioxidant compounds, simple sugars, amino acids, fatty acids and reasonable mineral contents was distinct in the phytochemical characterization of DPS. The major components detected in DPS analysis were the 5-(hydroxymethyl) furfural and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyranone. The induced callus of L. arabicus (seven weeks old) was supplemented with DPS at different concentrations (0, 2, 4, 8 and 10 g/l) in culture media. Treatment with 8 g/l DPS induced the highest antioxidant capacity, ascorbic acid content and secondary metabolites (total phenolics and flavonoids) in the produced callus. Stress biomarkers (hydrogen peroxide and malondialdehyde) were found in the control ranges except at 10 g/l DPS. The expression patterns of key genes involoved in secondary metabolism modulation, such as phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), chalcone isomerase (CHI), flavonol synthase (FLS) and deoxyxylulose phosphate reductoisomerase (DXR), were triggered after DPS treatments. Moreover, the quantitative profiling of phenolic and flavonoid compounds showed that supplementation with DPS, especially at 8 g/l, led to pronounced increases in most of the measured compounds.ConclusionThe marked upregulation of eliciting-responsive genes and overproduction of secondary metabolites provide molecular-based evidence for intensifying the principal pathways of phenylpropanoid, flavonoid and terpenoid biosynthesis. Overall, the present in vitro study highlights the stimulating capacity of DPS utilization to improve the bioactive components of L. arabicus at the physiological and molecular levels, enhancing its potential as a medicinal herb.