Chemical characterization and associations with climatic factors in Pinggu peach: A protected geographical indication product.

Improved detection of polyunsaturated fatty acids as phenacyl esters using liquid chromatography-ion trap mass spectrometry

Inhibitory effects of non-volatiles lipopeptides and volatiles ketones metabolites secreted by Bacillus velezensis C16 against Alternaria solani

Emergence of extended antibiotic resistance among several human bacterial pathogens often leads to the failure of existing antibiotics to treat bacterial infections worldwide. Hence, the present study is aimed to explore antibacterial activity of marine cyanobacterium against MDR pathogens. The cyanobacterial samples were collected and isolated from Thondi Palk Strait region. The isolate was subjected to polarity based solvent extraction and checked for their antibacterial activity against test bacterial pathogens. The active principles from chloroform extract of Oxynema thaianum (CEOT) were partially purified through thin layer chromatography (TLC). The active principle with highest activity was further characterized by FTIR, high performance liquid chromatography (HPLC) and gas chromatography mass spectrometry (GC-MS) analysis. Among the eight extracts tested, CEOT showed effective zone of clearance against ESBL producing Escherichia coli and Klebsiella pneumoniae in disc diffusion method. In TLC, all the purified five fractions were eluted and tested for their antibacterial activity against test pathogens. The third fraction showing maximum activity was subjected to HPLC analysis for checking its purity. In GC-MS analysis, 9-octadecenoic acid, methyl ester and hexadecanoic acid were identified as the major chemical compounds. Hence, the present study was concluded that O. thaianum ALU PBC5 is a promising agent to treat ESBL producing MDR bacterial pathogens. This is the pioneer study on screening and isolation of bioactive compounds from the marine cyanobacteria against MDR pathogens such as E. coli and K. pneumoniae. Here, 9-octadecenoic acid, methyl ester and hexadecanoic acid were identified as the major chemical compounds through TLC, FTIR, HPLC and GC-MS. From this screen, we identified the bioactive compounds against ESBL producing multidrug resistant pathogens such as E. coli and K. pneumoniae.

“Lumblija” is a Croatian autochthonous sweet bread which recently obtained a European Protected Geographical Indication (PGI) label. The peculiarity of “Lumblija” is the use of ingredients such as concentrated grape must, rose or herbal brandy, and various herbs and spices, mostly produced and collected in the area of the island of Korčula. To the author’s knowledge, the volatile compounds of “Lumblija” have not been investigated till now. The aim of this study was to characterise the volatile compounds responsible for the distinctive aroma of the traditional sweet bread “Lumblija”, which is widely appreciated for its unique sensory properties. Four samples of “Lumblija” were investigated. Headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry analysis (HS-SPME/GC-MS) was applied for volatile compound characterisation of “Lumblija” samples. A total of 50 volatile compounds were identified in the “Lumblija” samples. Volatile compounds belong to different chemical classes: terpenes, phenylpropanoids, alcohols, aldehydes, esters, ketones, aromatic hydrocarbons, and carboxylic acids. Among them, terpenes and phenylpropanoids were the most numerous and the most abundant volatile compounds. Most differences in the volatile compound profile of “Lumblija” samples can be attributed to some specific ingredients such as spices. The results of this study could be useful to establish a volatile compound profile of “Lumblija”, which could serve as an indicator of the authenticity and quality of this autochthonous bakery product.

Portulaca oleracea L., commonly known as purslane, is a weed with worldwide distribution and considerable medicinal uses due to its high levels of phytochemical compounds. However, until now, few studies have been conducted on the biochemical characterization of P. oleracea grown in Tunisia, a possible area of its origin as other North African countries. Therefore, the aim of the present study was to determine the phytochemical composition and antioxidant potential of leaves and stems from a Tunisian spontaneous population of purslane. Particularly, samples were analyzed for their proximate composition, pigments, and volatiles, whereas ethanolic and aqueous extracts were evaluated for their composition in phenolic compounds and in vitro antioxidant activities. Stems showed higher content of moisture (89.9%) and anthocyanins (4.61 µg g−1 dry matter, DM), whereas leaves revealed higher chlorophyll concentrations (7.42 mg g−1 DM). Significantly higher levels of phenolic compounds and antioxidant capacities (p < 0.05) were obtained in ethanolic extracts, compared with water extracts, irrespective of the analyzed plant part. A high antioxidant activity of stems was obtained, especially when extracted with ethanol. Headspace gas chromatography-mass spectrometry (GC-MS) analyses revealed six volatile classes with monoterpene hydrocarbons, oxygenated monoterpenes, and non-terpene derivatives as the highly represented compounds. Limonene (17.3–32.2%), carvone (38–46%), 2,6-dimethylcyclohexanol (2.2–6.4%), and nonanal (3.4–3.8%) were the most abundant volatiles. Based on the results of the present study, Tunisian purslane should deserve major consideration as an edible vegetable due to its richness in phytochemical compounds and, hence, for its potential health effects.

The effects of climate change on the distribution and biology of fisheries species have received substantial attention, but quantitative assessments of changes to taste and aroma determining compounds remain limited—despite sensory quality being a key driver of demand for most harvested species. Utilising the economically important blue swimmer crab (Portunus armatus), we tested the effects of temperature and salinity treatments aligned with near-future climate change projections on volatile and non-volatile sensory compounds that determine seafood flavour. Volatile compounds were analysed using solid phase microextraction and gas chromatography-mass spectrometry and non-volatiles were identified using liquid chromatography (mass spectrometry analysis). Multivariate analyses revealed that temperature, but not salinity, significantly affected the compositions of both volatile and non-volatile compounds in crab meat following a 30-day exposure period. Univariate analyses highlighted significant reductions in amino acids and amines associated with bitter and sweet organoleptic properties following exposure to elevated temperature. These results imply the potential for climate change to alter taste and aroma determining compounds in seafood, which could affect future harvesting priorities. Assessments of seafood sensory quality under climate change can produce valuable information to help predict shifts in fishing effort for harvested species that form the basis of important global fisheries.

In order to differentiate the extra virgin olive oils (EVOO) of different origin of purchase, such as monovarietal Italian EVOO with protected denomination of origin (PDO) and commercial-blended EVOO purchased in supermarkets, a number of samples was subjected to the analysis of volatile aroma compounds by both targeted gas chromatography/mass spectrometry (GC-MS) and untargeted profiling by comprehensive two-dimensional gas chromatography/mass spectrometry (GC×GC-TOF-MS), analysis of phenols by targeted high-performance liquid chromatography/mass spectrometry (HPLC-DAD-ESI/MS), and quantitative descriptive sensory analysis. Monovarietal PDO EVOOs were characterized by notably higher amounts of positive LOX-derived C6 and C5 volatile compounds, which corresponded to the higher intensities of all the assessed positive fruity and green odor sensory attributes. Commercial-blended EVOOs had larger quantities of generally undesirable esters, alcohols, acids, and aldehydes, which coincided with the occurrence of sensory defects in many samples. Many minor volatile compounds that were identified by GC×GC-TOF-MS were found to differentiate each of the two investigated groups. The differences between the groups with respect to phenols and taste characteristics were evident, but less pronounced. The results that were obtained in this study have undoubtedly confirmed the existence of the large heterogeneity of oils that are sold declared as EVOO. It was shown that GC-MS, GC×GC-TOF-MS, and HPLC-DAD-ESI/MS analyses have complementary outputs, and that their use in combination has advantages in supporting the results of sensory analysis and objectively differentiating these groups of EVOO.

Bragantina and Cingapura are the main black pepper (Piper nigrum L.) cultivars and the Pará state is the largest producer in Brazil with about 90% of national production, representing the third largest production in the world. The infection of Fusarium solani f. sp. piperis, the causal agent of Fusarium disease in black pepper, was monitored on the cultivars Bragantina (susceptible) and Cingapura (tolerant), during 45 days’ post infection (dpi). Gas Chromatography-Mass spectrometry (GC-MS) analysis of the volatile concentrates of both cultivars showed that the Bragantina responded with the production of higher contents of α-bisabolol at 21 dpi and a decrease of elemol, mostly at 30 dpi; while Cingapura displayed an decrease of δ-elemene production, except at 15 dpi. The phenolic content determined by the Folin Ciocalteu method showed an increase in the leaves of plants inoculated at 7 dpi (Bragantina) and 7–15 dpi (Cingapura); in the roots, the infection caused a phenolic content decrease in Bragantina cultivar at 45 dpi and an increase in the Cingapura cultivar at 15, 30 and 45 dpi. High Performance Liquid Chromatography-Mass spectrometry (HPLC-MS) analysis of the root extracts showed a qualitative variation of alkamides during infection. The results indicated that there is a possible relationship between secondary metabolites and tolerance against phytopathogens.

Gamma irradiation is one of the preservation techniques used to increase the shelf life of foods. The current study was aimed to determine the volatile flavor contents of melon (Cucumis melo L.) seeds and the impact of gamma radiation upon these compounds. The seeds were irradiated with gamma rays at 1, 5, 10, and 20 kGy doses. The volatile compounds were extracted by simultaneous distillation extraction (SDE), using n-pentane/diethyl ether (1:1, v/v) and determined by gas chromatography-mass spectrometry (GC-MS). A total of 70 volatile flavor compounds were identified in the control, with 2,3-butanediole (18.01%) and 1-hexanol (6.06%) as the major compounds. The number and percentage of the volatile compounds varied with the gamma irradiation doses. Twenty-eight volatile compounds were present in the non-irradiated and irradiated samples at different concentrations. Up to the recommended gamma irradiation dose of 10 kGy, the number of volatile flavor compounds generally increased. There were changes in both the number and percentages of the identified volatile flavor compounds following gamma irradiation of the Cucumis melo L seeds.

Nang roasting is a traditional lamb processing method in Xinjiang (China) with a history of thousands of years. This study comprehensively evaluated the volatile and nonvolatile compounds of oyster cuts of roasted lamb at different processing stages of Nang roasting using gas chromatography mass spectrometry and amino acid automatic analyzer, respectively. Results indicated that aldehydes were the dominant profiles of volatile compounds, and hexanal, nonanal, octanal, (E)-2-nonenal, (E, E)-2,4-decadienal, (E, E)-2,4-nonadienal and 1-octen-3-ol were the key volatile compounds or aroma contributors to roasted oyster cuts. Isoamylol and 3-hydroxy-2-butanone could differentiate fresh and marinated oyster cuts from roasted ones; (E)-2-nonenal, (E, E)-2,4-decadienal, 1-octen-3-ol, hexanal, octanal, nonanal and (E, E)-2,4-nonadienal could differentiate Nang roasted oyster cuts of 60 min from those of 15, 30 and 45 min. Umami amino acids and sweet amino acids are the dominant profiles of nonvolatile compounds; glutamic acid, alanine and 5′-IMP were the key free amino acids or taste contributors to roasted oyster cuts. Glutamic acid, alanine and 5′-IMP could differentiate fresh and marinated oyster cuts from roasted samples. This work provided theoretical support for the control of flavor attributes of roasted lamb with traditional Nang roasting.

Early identification of disease onset is regarded as an important factor for successful medical intervention. However, cancer and other long-term latency diseases are rare and may take years to manifest clinically. As such, there are no gold standards with which to immediately validate proposed preclinical screening methodologies. There is evidence that dogs can sort samples reproducibly into yes/no categories based on case-control training, but the basis of their decisions is unknown. Because dogs are sniffing air, the distinguishing chemicals must be either in the gas-phase or attached to aerosols and/or airborne particles. Recent biomonitoring research has shown how to extract and analyze semi- and non-volatile compounds from human breath in exhaled condensates and aerosols. Further research has shown that exhaled aerosols can be directly collected on standard hospital-style olefin polypropylene masks and that these masks can be used as a simple sampling scheme for canine screening. In this article, detailed liquid chromatography-high resolution mass spectrometry (LC-HR-MS) with Orbitrap instrumentation and gas chromatography-mass spectrometry (GC-MS) analyses were performed on two sets of masks sorted by consensus of a four-dog cohort as either cancer or control. Specifically, after sorting by the dogs, sample masks were cut into multiple sections and extracted for LC-MS and GC-MS non-targeted analyses. Extracts were also analyzed for human cytokines, confirming the presence of human aerosol content above levels in blank masks. In preliminary evaluations, 345 and 44 high quality chemical features were detected by LC-MS and GC-MS analyses, respectively. These features were used to develop provisional orthogonal projection to latent structures-discriminant analysis (OPLS-DA) models to determine if the samples classified as cancer (case) or non-cancer (control) by the dogs could be separated into the same groups using analytical instrumentation. While the OPLS-DA model for the LC-HR-MS data was able to separate the two groups with statistical significance, although weak explanatory power, the GC-MS model was not found to be significant. These results suggest that the dogs may rely on the less volatile compounds from breath aerosol that were analyzed by LC-HR-MS than the more volatile compounds observed by GC-MS to sort mask samples into groups. These results provide justification for more expansive studies in the future that aim to characterize specific chemical features, and the role(s) of these features in maintaining homeostatic biological processes.

Mushrooms have been consumed for centuries and have recently gained more popularity as an important source of nutritional and pharmaceutical compounds. As part of the valorization of mushroom species in northern Morocco, the current study aimed to investigate the chemical compositions and antioxidant properties of two wild edible mushrooms, Paralepista flaccida and Lepista nuda. Herein, the bioactive compounds were determined using spectrophotometer methods, and results showed that the value of total phenolic content (TPC) was found to be higher in P. flaccida (32.86 ± 0.52 mg) than in L. nuda (25.52 ± 0.56 mg of gallic acid equivalents (GAEs)/mg of dry methanolic extract (dme)). On the other hand, the value of total flavonoid content (TFC) was greater in L. nuda than in P. flaccida, with values of 19.02 ± 0.80 and 10.34 ± 0.60 mg of (+)-catechin equivalents (CEs)/g dme, respectively. Moreover, the ascorbic acid, tannin, and carotenoids content was moderate, with a non-significant difference between the two samples. High-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis allowed the identification and quantification of thirteen individual phenolic compounds in both P. flaccida and L. nuda, whereas p-Hydroxybenzoic acid was recognized as the major compound detected, with values of 138.50 ± 1.58 and 587.90 ± 4.89 µg/g of dry weight (dw), respectively. The gas chromatography-mass spectrometry (GC-MS) analysis of methanolic extracts of P. flaccida and L. nuda revealed the presence of sixty-one and sixty-six biomolecules, respectively. These biomolecules can mainly be divided into four main groups, namely sugars, amino acids, fatty acids, and organic acids. Moreover, glycerol (12.42%) and mannitol (10.39%) were observed to be the main chemical compositions of P. flaccida, while L. nuda was predominated by linolelaidic acid (21.13%) and leucine (9.05%). L. nuda showed a strong antioxidant property, evaluated by DPPH (half maximal effective concentration (EC50) 1.18-0.98 mg/mL); β-carotene bleaching (EC50 0.22-0.39 mg/mL); and reducing power methods (EC50 0.63-0.48 mg/mL), respectively. These findings suggested that both mushrooms are potential sources of various biomolecules, many of which possess important biological activities which are interesting for the foods and pharmaceuticals industry.

The processing of medicinal and aromatic plants (MAPs) results in the production of a significant amount of plant by-products; herbal material of inferior quality and/or unusable plant parts that are not commercially exploitable. An extensive study of Greek native species was performed toward the production of innovative bioactive products using as raw materials the by-products obtained from the processing of cultivated MAPs. Origanum vulgare subsp. hirtum (oregano), Sideritis scardica (Greek mountain tea), Thymus vulgaris (thyme), and Matricaria recutita (chamomile) were selected due to their wide use for the preparation of beverages and culinary purposes. The determination of the percentage of the post-harvest processing by-products was performed for a 3 years period (2018–2020). Results showed that by-products derived from the above-mentioned species' processing constitute 64% (thyme), 54% (oregano), 37% (Greek mountain tea), and 24% (chamomile) of the total processed mass. To value the by-products as a potent source of bioactive ingredients, superior and inferior quality herbal material of the aforementioned plant species were extracted by an ultrasonic assisted extraction method. Hydroalcoholic extracts were chemically investigated using high-performance thin layer chromatography (HPTLC) and liquid chromatography-mass spectrometry (LC-MS) techniques. In addition, their free radical scavenging activity and total phenolic content (TPC) were estimated. Based on the results, herbs by-products revealed similar chemical content to the superior herbal material by the means of HPTLC and LC-MS analysis. In addition, strong free radical scavenging related to a high phenolic content was detected in the case of thyme, oregano, and Greek mountain tea. Moreover, the gas chromatography-mass spectrometry (GC-MS) analyses of the essential oils (EOs) of oregano and thyme by-products revealed the presence of carvacrol, thymol, γ-terpinene, and p-cymene among the major constituents. Finally, the LC-MS analyses of aqueous extracts of Greek mountain tea and chamomile by-products led to the identification of several bioactive compounds, such as flavonoids and phenylpropanoids. Overall, the presence of bioactive constituents in by-products, such as terpenes, phenolic compounds, and flavonoids underly their potent use as food antimicrobial and antioxidant additives, in the preparation of high added-value products, such as enriched aromatic edible oils, and innovative herbal teas, such as instant beverages.

Royal jelly produced by nurse bees from tea tree (tea royal jelly) is a special bee product in China and it is popular with consumers owing to its multiple healthcare functions. However, the volatile compound profile of tea royal jelly has not been investigated. To obtain a comprehensive understanding of volatile compound profile of tea royal jelly, a method based on headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) and chemometric analysis was applied. Moreover, two royal jelly samples produced from pagoda tree were also investigated to reveal the difference in volatile compounds between royal jelly produced from tea tree and other plants. A total of 66 volatile compounds were identified in tea royal jelly, including 16 alkanes, 14 aldehydes, 9 alcohols, 9 ketones, 8 esters and lactones, 5 phenols, 2 organic acids, and 3 other compounds, and most of them were discovered in royal jelly for the first time. Notably, α-ionone, an important aroma compound in tea, was first identified in tea royal jelly. Moreover, the result of chemometric analysis indicates a significant difference on volatile compound profile between royal jelly produced from tea and pagoda trees. To sum up, 35 differential compounds were identified and they could well distinguish royal jelly samples. Our data offers the first characterization of volatile compound profile of tea royal jelly and significantly expands the knowledge of volatile compounds in royal jelly. It is potentially useful as a new approach to distinguish royal jelly produced from different botanical origins.

Species distribution models (SDMs) are valuable tools for assessing species' responses to environmental factors and identifying areas suitable for their survival. The careful selection of input variables is critical, as their interactions and correlations with other environmental factors can affect model performance. This study evaluates the influence of climate and soil variables on the performance of SDMs for 5033 Australian terrestrial vascular plant species, representing the largest phylogenetic diversity of native flora assessed in such an analysis. Using an ensemble of correlative models, we assessed the predictive performance of climate and soil variables, individually and in combination, across four distinct ecoregions: Desert (n = 640 species), Mediterranean (n = 1246), Temperate (n = 1936), and Tropical (n = 1211). Our results demonstrate that on a continental scale, climate variables have a greater influence on plant distributions than soil variables. Although incorporating soil and climate variables enhanced model performance in some ecoregions, our results indicate that relying solely on small-scale variables such as soil may increase the likelihood of underfitting. The most influential predictor variables in the models varied across ecoregions and between specialist and generalist species. Mean annual rainfall (bio1) was consistently a strong climate predictor variable across ecoregions, but other climate variables became more important when analyses were restricted to ecoregion-specific species (i.e., specialists). Soil organic carbon (SOC) was the most important soil variable in the Temperate and Tropical ecoregions across generalist and specialist species. In the Mediterranean ecoregion, clay content (CLY) became more important than SOC when analyses were restricted to ecoregion-specific species, whereas nitrogen total organic (NTO) was consistently the strongest predictor soil variable for plants in the Desert. Our findings have significant implications for understanding the interplay between climate, soil, and plant distribution within diverse ecoregions. This study serves as a foundation for developing more accurate SDM predictions.