Gas Chromatograph-mass Spectrometer Research Articles

Ultrasonic treatment maintains the flavor of the melon juice

Thermal treatment usually leads to the flavor deterioration of melon juice. This study was initiated to evaluate the retention effect of ultrasonic (US) and ultra-high pressure (UHP) on volatile components of melon juice by gas chromatography-mass spectrometer (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS). The electronic nose, electronic tongue, and GC-IMS analysis showed that US was much better way to contain the flavor of melon juice than UHP was does. The correlation coefficient between the US and the control was as high as 0.99. The concentration of characteristic aroma components in melon juice after ultrasonic treatment was 2.77 times and 3.02 times higher than that in the control and UHP, respectively. Moreover, the US treatment gave no significant difference in the total soluble solids, pH, and color of the juice. And it dramatically enhanced the flavor profile of melon juice.

Cryptosporidium infection induced the dropping of SCFAS and dysbiosis in intestinal microbiome of Tibetan pigs.

The infection of Cryptosporidium in pigs causes digestive system ailments, diarrhea and weight loss serving as an economic burden, especially in newborn animals. The bacterial fermentation products of short-chain fatty acids have important roles in immune function, microbiota regulation, osmotic balance and metabolism. However, till now little knowledge is available about the effect of Cryptosporidium infection on microbiota and SCFAs in plateau pigs. Hence, we performed this study to explore the response of microbiota and SCFAs in the natural infection of Cryptosporidium in Tibetan pigs. Cryptosporidium positive (infected, G) and negative samples (healthy, J) in our previous study were used for high throughputsequencing and Gas Chromatography-Mass Spectrometer analysis. Over 81000 and 74000 filtered sequences were detected in healthy and infected Tibetan pigs, respectively. Lower sample richness and evenness were observed in Cryptosporidium infection, as alpha diversity analysis found that chao1 (p<0.05), faith_pd (p<0.05), and observed_features in group G were significantly lower than pigs in group J. A total of 4 and 27 significant different phyla and genera were found between group G and J. The changed genera were Psychrobacter, Desemzia, Succiniclasticum, Treponema, Campylobacter, Atopobium, Olsenella, Pediococcus, Peptococcus, Sharpea, Desulfovibrio, Acinetobacter, Rhodococcus, Anaerostipes, Turicibacter, Lactobacillus, RFN20, Phascolarctobacterium, Roseburia, Megasphaera, Streptococcus, Blautia, Lachnospira, rc4_4, Gemmiger, Dorea, Oribacterium and Prevotella, which affected the microbiota functions with 360 abundance changed enzymes, and pathways in L1, L2 and L3 levels of KEGG. The concentration of acetic acid (p<0.01), butyric acid (p<0.05) and caproic acid (p<0.01) were lower in group G. In conclusion, the present study herein uncovered that the host responses to Cryptosporidium infection in Tibetan pigs with 27 of significantly changed genera decreased SCFAs in pigs, which may provide insights in further developing novel therapy against this protozoan.

Reconstructing the Age of Formation of some Crude Oil samples from the Niger Delta Basin using Biomarker Fingerprinting

The Niger Delta Basin is a prolific petroleum province and is currently the only basin in which commercial petroleum production strives in Nigeria. The Niger Delta Basin has received a lot of research attention but with fewer studies regarding the reconstruction of the age of source rocks from their crude oils using biomarkers. The study aimed at reconstructing the age of the Niger Delta source rocks from crude oils samples from the Basin. The age determination of the sample set was attempted by looking at individual age-specific biomarkers that suggested a source age as well as looking at them together to have a clearer indication of the likely source age. Thirteen (13) crude oil samples from the “Y” Field of the Niger Delta Basin were subjected to Gas Chromatography-Mass Spectrometer analysis. The biomarkers used in this study were; oleanane index (OI), C28/ C29 ratio, C30 /(C27-C30) ratio, and Pr/Ph (pristane/phytane) ratio, with corresponding mean values of 1.08, 0.76, 0.28, and 1.12 respectively. The biomarker data based on some age-specific biomarkers, both individually and especially when used together, suggests a Tertiary age for the source rock that generated the crude oils. These results are based on the occurrences of oleanane, Pr/Ph ratios, and the high C28/C29 ratios, all indicating Tertiary age source rock.

Chiral pesticides levels in peri-urban area near Yangtze River and their correlations with water quality and microbial communities.

Pesticides are considered to be the second-largest non-point source pollution in water. Our research assayed the river network of typical agricultural areas in the middle and lower Yangtze River as the study area. Pesticides residues in aquatic environment were determined by QuEChERS, combined with high-performance liquid chromatography tandem mass spectrometry, or gas chromatograph-mass spectrometer. At chiral pesticides' levels, we detected pesticides contents in water, classified and counted the types of pesticides, and analyzed their environmental risk assessment. Furthermore, potential correlations between chiral pesticides concentrations and water quality indicators were assayed. Additionally, we explored their relations with microbial communities at species levels. Enantiomers of Diclofop-methyl, Ethiprole, Difenoconazole and Epoxiconazole were enantioselectively distributed. More interestingly, due to various chiral environment of the sampling site, the enantiomers of Tebuconazole Acetochlor, Glufosinate ammonium and Bifenthrin had completely different distributions at different sites. Based on that, the chiral pesticides Diclofop-methyl, Bifenthrin, Ethiprole, Tebuconazole and Difenoconazole are enantioselective to the risk of aquatic environment. Generally, enantiomeric selectivity had high positive correlations with total nitrogen and phosphorus. Then we found that chiral fate behavior of Tebuconazole and Paichongding in water might be affected by prokaryotes. In addition, the chiral behavior of Diclofop-methyl, Propiconazole, Difenoconazole, and Tebuconazole isomers in water might be negatively affected by eukaryotes. That research helped us to comprehensively understand the impact of non-point source pollution of chiral pesticides in aquatic environment and provided basic data support for developing biological and water quality indicators for monitoring pollution in aquatic environment.

Secondary Organic Aerosol Formation from Semi-Volatile and Intermediate Volatility Organic Compounds in the Fall in Beijing

Intermediate volatility organic compounds (IVOCs) and semi-volatile organic compounds (SVOCs) have recently been proposed as important precursors of secondary organic aerosol (SOA). In the present work, 97 volatile organic compounds (VOCs) and 80 intermediate volatility and semi-volatile organic compounds (IVOCs and SVOCs) were measured by online gas chromatography-mass spectrometer/flame ionization detection (GC-MS/FID), and offline thermal desorption gas chromatography-mass spectrometer (TD-GC-MS), respectively. The average concentration of speciated VOCs, IVOCs, and SVOCs were 22.36 ± 9.02 μg m−3, 1.01 ± 0.32 μg m−3, and 0.10 ± 0.17 μg m−3. Alkanes and polycyclic aromatic hydrocarbons (PAHs) are the main compounds of total S/IVOCs. With the increase in molecular weight, the concentrations decreased in the gas phase, while increasing in the particle phase. Vehicular emission is the most significant source according to the carbon preference index (CPI) and the carbon of the most abundant alkane (Cmax). The yield method was used to estimate SOA from the oxidation of VOCs and S/IVOCs. The estimated SOA mass from IVOCs and SVOCs (0.70 ± 0.57 μg m−3) was comparable to that of VOCs (0.62 ± 0.61 μg m−3), and the oxidation of PAHs and alkanes took up 28.70 ± 8.26% and 51.97 ± 20.77% of the total SOA estimation, respectively. Compared to previous work, our study provided detailed molecular information of ambient S/IVOC species and elucidated their importance on SOA formation. Despite their low concentration, S/IVOCs species are important SOA precursors which shared comparable contribution compared with VOCs.

The Use of Coprostanol, Epi-Coprostanol and Cholesterol in Evaluating Potential Sewage Input from Downstream River towards Marine Environment

Contamination of sewage is a major concern in the river and marine environments since sewage can cause disease and ecosystem health problems. Worldwide, coprostanol, coprostanol and epi-coprostanol were used in sewage assessment due to their resistance towards environmental stressor. This study assessed the distribution of coprostanol, epi-coprostanol and cholesterol in the particulate of sewage treatment plant (STP) effluents and river water samples. The targeted analytes were extracted using sonication and quantified using gas chromatography-mass spectrometer (GC-MS). The potential sewage pollution in the river and marine environments were assessed using diagnostic approach and linear regression technique. Based on the result, cholesterol (mean = 15.6 mg L-1) was found to be higher than coprostanol (mean = 6.0 mg L-1) and epi coprostanol (mean= 2.3 mg L-1) in STPs samples. Similar to STPs, cholesterol (mean= 4.6 mg L-1) also was detected higher than coprostanol (mean= 2.4 mg L-1) and epi-coprostanol (mean= 2.4 mg L-1) in the river water samples. The double plot ratios of epi-coprostanol/cholesterol versus epi-coprostanol/coprostanol revealed the discharge of treated and untreated sewage into the river water. The river water samples were impacted by treated sewage and non-human sources. The linear regression analysis indicates potential moderate to high increasing trend (p&lt;0.05) of sewage discharge towards downstream of the river. These findings provide an enhanced means in assessing sewage contamination input into the river and its potential effect towards the marine ecosystem.

The potential effect of ethyl alcohol elution from liner type denture adhesives on breath alcohol concentration and determination of drunk driving

Background/purposeThe application of liner type denture adhesives containing ethyl alcohol (EtOH) may result in the person being considered a drunk driver, which is a social problem. This study measured the amount of EtOH loss from the materials and its effect on breath alcohol concentration (BrAC). Materials and methodsThe amount of EtOH loss of three liner type denture adhesives was measured using a gas chromatograph-mass spectrometer. Five specimens were measured for each material. The BrAC of ten participants who wore the palatal plate lined with the material having the highest amount of EtOH elution was also determined using an alcohol detector every 5 min for 60 min. The threshold for drunk driving was a BrAC of 0.15 mg/L or more. ResultsSignificant differences were found in the amount of EtOH elution among the three materials. For all materials, the elution amount from the start of immersion to 30 min was significantly larger than that of the following 30 min (P < 0.05). BrAC values of the participants reached their maxima 5 min after insertion of the materials, and 80% of participants surpassed the threshold for drunk driving. However, no participants reached the threshold for drunk driving after 50 min. ConclusionThe results suggest that a determination of drunk drinking will not be made when 1 h or more has passed after insertion of a denture lined with a liner type denture adhesive into the mouth, though a determination of drunk driving may exist due to EtOH from the materials.

Degradation of petroleum pollutants in oil-based drilling cuttings using an Fe2+-based Fenton-like advanced oxidation processes.

Oil-based drilling cuttings (OBDC) contain a large amount of total petroleum hydrocarbon (TPH) pollutants, which are hazardous to the environment. In this study, Fe2+-activating hydrogen peroxide (Fe2+/H2O2), peroxymonosulfate (Fe2+/PMS), and peroxydisulfate (Fe2+/PDS) advanced oxidation processes (AOPs) were used to treat OBDC due to the difference in the degradation capacity of TPH caused by the type of free radical generated and effective activation conditions observed for the different oxidants studied. The results showed that the oxidant concentration, Fe2+ dosage, and reaction time in the three AOPs were greatly positively correlated with the TPH removal rate in a certain range. The initial pH value had a significant effect on the Fe2+/H2O2 process, and its TPH removal rate was negatively correlated in the pH range from 3 to 11. However, the Fe2+/PMS and Fe2+/PDS processes only displayed lower TPH removal rates under neutral conditions and tolerated a wider range of pH conditions. The optimal TPH removal rates observed for the Fe2+/H2O2, Fe2+/PMS, and Fe2+/PDS processes were 45.04%, 42.75%, and 44.95%, respectively. Fourier transform infrared spectrometer and gas chromatography-mass spectrometer analysis showed that the alkanes in OBDC could be effectively removed using the three processes studied, and their degradation ability toward straight-chain alkanes was in the order of Fe2+/PMS > Fe2+/PDS > Fe2+/H2O2, among which Fe2+/PMS exhibited the optimal removal effect for aromatic hydrocarbons. Scanning electron microscope, energy dispersive spectroscopy, and X-ray diffraction results showed no significant changes in the elemental and mineral composition of OBDC before and after treatment. Therefore, this study provided a theoretical reference for the effective degradation of TPH pollutants in OBDC.

Selection and Analytical Performances of the Dragonfly Mass Spectrometer Gas Chromatographic Columns to Support the Search for Organic Molecules of Astrobiological Interest on Titan.

Titan is a key planetary body for astrobiology, with the presence of a subsurface ocean and a dense atmosphere, in which complex chemistry is known to occur. Approximately 1-Titan-year after the Cassini-Huygens mission arrived in the saturnian system, Dragonfly rotorcraft will land on Titan's surface by 2034 for an exhaustive geophysical and chemical investigation of the Shangri-La organic sand sea region. Among the four instruments onboard Dragonfly, the Dragonfly Mass Spectrometer (DraMS) is dedicated to analyze the chemical composition of surface samples and noble gases in the atmosphere. One of the DraMS analysis modes, the Gas Chromatograph-Mass Spectrometer (GC-MS), is devoted to the detection and identification of organic molecules that could be involved in the development of a prebiotic chemistry or even representative of traces of past or present life. Therefore, DraMS-GC subsystem should be optimized to detect and identify relevant organic compounds to meet this objective. This work is focused on the experimental methods employed to select the chromatographic column to be integrated in DraMS-GC, to assess the analytical performances of the column selected, and also to assess the performances of the second DraMS-GC column, which is devoted to the separation of organic enantiomers. Four different stationary phases have been tested to select the most relevant one for the separation of the targeted chemical species. The results show that the stationary phase composed of polymethyl (95%) diphenyl (5%) siloxane is the best compromise in terms of efficiency, robustness, and retention times of the molecules. The combination of the general and the chiral columns in DraMS is perfectly suited to in situ chemical analysis on Titan and for the detection of expected diverse and complex organic compounds.

Genome-wide identification of the CER1 gene family in apple and response of MdCER1-1 to drought stress.

Plant cuticular wax was a major consideration affecting the growth and quality of plants through protecting the plant from drought and other diseases. According to existing studies, CER1, as the core enzyme encoding the synthesis of alkanes, the main component of wax, can directly affect the response of plants to stress. However, there were few studies on the related functions of CER1 in apple. In this study, three MdCER1 genes in Malus domestica were identified and named MdCER1-1, MdCER1-2, and MdCER1-3 according to their distribution on chromosomes. Then, their physicochemical properties, sequence characteristics, and expression patterns were analyzed. MdCER1-1, with the highest expression level among the three members, was screened for cloning and functional verification. Real-time fluorescence quantitative PCR (qRT-PCR) analysis also showed that drought stress could increase the expression level of MdCER1-1. The experiment of water loss showed that overexpression of MdCER1-1 could effectively prevent water loss in apple calli, and the effect was more significant under drought stress. Meanwhile, MdYPB5, MdCER3, and MdKCS1 were significantly up-regulated, which would be bound up with waxy metabolism. Gas chromatography-mass spectrometer assay of wax fraction makes known that overexpression of MdCER1-1 apparently scaled up capacity of alkanes. The enzyme activities (SOD, POD) of overexpressed apple calli increased significantly, while the contents of proline increased compared with wild-type calli. In conclusion, MdCER1-1 can resist drought stress by reducing water loss in apple calli epidermis, increasing alkanes component content, stimulating the expression of waxy related genes (MdYPB5, MdCER3, and MdKCS1), and increasing antioxidant enzyme activity, which also provided a theoretical basis for exploring the role of waxy in other stresses.

In Vitro and In Silico Screening Analysis of Artabotrys sumatranus Leaf and Twig Extracts for α-Glucosidase Inhibition Activity and Its Relationship with Antioxidant Activity

Artabotrys sumatranus is one of the Artabotrys species, which lives in Sumatera, Java, and Borneo in Indonesia. No research has been found related to its activity. The objective of this study was to explore the potential of A. sumatranus leaf and twig extracts as the source of an anti-diabetic agent through the α-glucosidase inhibition mechanism, as well as the relationship between the antioxidant and the α-glucosidase inhibition activities in these extracts. Ethanol extracts from leaf and twig A. sumatranus were subjected to several assays: total phenolic content, total flavonoid content, antioxidant activity using DPPH (2,2-diphenyl-1-picrylhydrazyl), radical scavenging activity, and FRAP (ferric reducing antioxidant power) analysis, as well as α-glucosidase inhibition. Later, GC-MS (gas chromatography-mass spectrometer) and LC-MS/MS (liquid chromatography-mass spectrometer/mass spectrometer) analysis were conducted to identify the compounds inside the extracts. The identified compounds were tested for potential α-glucosidase inhibition activity using a molecular docking simulation. As a result, the A. sumatranus leaf extract showed more potential than the twig extract as α-glucosidase inhibitor and antioxidant agent. In addition, from the comparison between the measured quantities, it can be deduced that most of the α-glucosidase active compounds in the A. sumatranus are also antioxidant agents. Several active compounds with a high affinity to α-glucosidase inhibition were identified using the molecular docking simulation. It was concluded that A. sumatranus twig and leaf extracts seem to be potential sources of α-glucosidase inhibitors.

Compositional changes of CH, O, and N moieties in petroleum ether-extractable portions from the three-step mild degradation of Dongming lignite

Migration and distribution changes of CH, O, and N moieties in Dongming lignite (DL) derived petroleum ether-extractable portions (EPs), including cyclohexane (EPC), ethanol (EPE), and cyclohexane/ethanol (EPCE) systems were focused on in this work. Overall, EPC and EPE are rich in aromatics with short side-chains, while EPCE has the highest aromaticity. The gas chromatograph/mass spectrometer (GC/MS) analysis indicated that CH, >C-O-, and >C=O are three main parts. Alkanes in EPC are mainly concentrated in C11-C31 and the pristane/phytane ratio is 0.7, indicating the early anaerobic diagenesis of DL. Arenes are dominated by mono- to tricyclic compounds. The identification of these native compounds with low aromaticity implies the low coalification degree of DL. In addition, >C-O- and >C=O moieties predominate in EPE and EPCE. The differences in characteristic oxygenates, such as phenols and acetophenones, further indicated that ethanol involves in the cleavage of >Cal-O-Cal<, >Cal-O-Car<, and >Cal-Cal< bridged bonds in DL. GC/MS-undetectable oxynitrides, such as N1O1 and N2O1-4 species, were also discovered by Orbitrap MS. The compositional changes of O/N-containing species are related to source differences: (1) Step 1: the release of intrinsic fragments, (2) Step 2: the cleavage of weak O/N-containing covalent bonds, and (3) Step 3: the cleavage of covalent bonds with higher bond dissociation energies and the dissolution of macromolecules. The investigation on the changes of CH, O, and N moieties during the three-step mild degradation is beneficial to the secondary upgrading and value-added utilization of DL-derived soluble portions.

Isolation, purification, and structural elucidation of Stropharia rugosoannulata polysaccharides with hypolipidemic effect.

Stropharia rugosoannulata is a widely grown edible mushroom with a high nutritional value. S. rugosoannulata polysaccharides is one of the most important bioactive components of S. rugosoannulata and has a wide range of activities. A S. rugosoannulata polysaccharides, named SRF-3, was derived from the S. rugosoannulata extraction by freeze-thaw combine with hot water extraction method, then prepareed with DEAE-cellulose column and Sephacryl S-200 HR gel column, and its hypolipidemic activity was determined. The structural characteristics of SRF-3 were analyzed by infrared spectral scanning (FT-IR), ultra-high performance liquid chromatography (UHPLC), acid hydrolysis, methylation analysis, nuclear magnetic resonance (NMR), and Gas Chromatography-Mass Spectrometer (GC-MS). SRF-3 is composed of mannose, galactose, methyl galactose and fructose with ratios of 16, 12, 58 and 12, respectively. In addition, the average relative molecular mass of SRF-3 is approximately 24 kDa. The main chain of SRF-3 is mainly composed of repeating α-D-1,6-Galp and α-D-1,6-Me-Galp units, with branches in the O-2 position of Gal. The structure is presumed to be a mannogalactan, with a small amount of t-β-D-Manp present as a side chain. Hypolipidemic activity assay showed that SRF-3 had good antioxidant and hypolipidemic effects in vitro, suggesting that SRF-3 have potential application in reducing liver fat accumulation.

Yinchen Linggui Zhugan decoction ameliorates high fat diet-induced nonalcoholic fatty liver disease by modulation of SIRT1/Nrf2 signaling pathway and gut microbiota.

Yinchen Linggui Zhugan decoction (YLZD) is an effective and classical traditional herbal prescription for treating the nonalcoholic fatty liver disease (NAFLD) and has been proven to be effective in the regulation of lipid metabolism disorder and attenuate inflammation for a NAFLD rat model. However, the exact underlying mechanism has not been elucidated. In the current study, a NAFLD rat model was established using a high-fat diet (HFD) for 10 weeks, followed by YLZD treatment with 1.92 g/kg/day for 4 weeks to explore the mechanisms of YLZD. Our results showed that YLZD decreased the hepatic lipid deposition, restored the liver tissue pathological lesions, inhibited the expression of oxidative stress, and decreased the inflammatory cytokines levels. Meanwhile, the genes and proteins expressions of SIRT1/Nrf2 signaling pathway together with downstream factors including HO-1 and NQO1 were elevated in the YLZD treated NAFLD rats. For further elaborating the upstream mechanism, short-chain fatty acids (SCFAs) in serum and feces were measured by liquid chromatograph mass spectrometer and gas chromatograph mass spectrometer, and the differences in gut microbiota of rats in each group were analyzed through high-throughput sequencing of 16S rRNA. The results demonstrated that the contents of butyric acid (BA) and total SCFAs in YLZD-treated NAFLD rats were significantly increased in serum and feces. 16S rRNA sequencing analysis illustrated that YLZD intervention led to a modification of the gut microbiota composition, with a decrease of Oribacterium, Lactobacillus and the ratio of Firmicutes/Bacteroides, as well as the increase in SCFAs-producing bacteria such as Christensenellaceae, Clostridia, Muribaculaceae, and Prevotellaceae. Spearman rank correlation analysis indicated that BA and total SCFAs were negatively co-related with oxidative stress-related factors and inflammatory cytokines, while they were positively co-related with SIRT1/Nrf2 pathway related genes and proteins. Furthermore, in vitro study confirmed that BA effectively reduced oxidative stress by activating SIRT1/Nrf2 signaling pathway in L02 cells. Together, the present data revealed YLZD could ameliorate HFD-induced NAFLD in rats by the modulation of SIRT1/Nrf2 signaling pathway and gut microbiota.

Microwave-assisted synthesis of biodiesel by a green carbon-based heterogeneous catalyst derived from areca nut husk by one-pot hydrothermal carbonization

In this study, we have synthesized a solid acid catalyst by areca nut husk using low temperature hydrothermal carbonization method. The fabricated catalyst has enhanced sulfonic actives sites (3.12%) and high acid density (1.88 mmol g−1) due to –SO3H, which are used significantly for effective biodiesel synthesis at low temperatures. The chemical composition and morphology of the catalyst is determined by various techniques, such as Fourier transform infrared (FTIR), powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Scanning electron microscope (SEM), Energy disruptive spectroscopy (EDS), Mapping, Thermogravimetric analysis (TGA), CHNS analyzer, Transmission electron microscopy (TEM), particle size analyzer, and X-ray photoelectron spectroscopy (XPS). Acid–base back titration method was used to determine the acid density of the synthesized material. In the presence of the as-fabricated catalyst, the conversion of oleic acid (OA) to methyl oleate reached 96.4% in 60 min under optimized conditions (1:25 Oleic acid: methanol ratio, 80 °C, 60 min, 9 wt% catalyst dosage) and observed low activation energy of 45.377 kJ mol−1. The presence of the porous structure and sulfonic groups of the catalyst contributes to the high activity of the catalyst. The biodiesel synthesis was confirmed by gas-chromatography mass spectrometer (GC–MS) and Nuclear magnetic resonance (NMR). The reusability of the catalyst was examined up to four consecutive cycles, yielding a high 85% transformation of OA to methyl oleate on the fourth catalytic cycle.

Chilling-induced peach flavor loss is associated with expression and DNA methylation of functional genes

IntroductionFlavor is a major contributor to consumer preference. Despite being effective at extending the fruit’s commercial life, cold storage also results in a significant loss of flavor volatiles. To date, there has been few studies on the metabolic dynamics and the mechanism underlying the regulatory networks that modulate flavor loss during cold storage for fruit. MethodsThe volatile contents were detected by Gas Chromatography–Mass Spectrometer (GC–MS). Weighted gene co-expression network analysis (WGCNA) was used to identify structure genes and transcription factors (TFs). DNA methylation was analyzed by whole-genome methylation sequencing during cold storage. ResultsWe generated a temporal map, over hourly to weekly timescales, for the effects of chilling on flavor volatiles by combining metabolome, transcriptome, and DNA methylome in peach fruit. Based on the big data analysis, we developed a regulatory network for volatile formation and found that a decrease in volatiles during cold storage was significantly correlated with a decrease in the expression of synthesis genes. Moreover, TFs associated with these structure genes were identified. Expression of genes involved in ethylene biosynthesis was reduced while cold tolerance pathway was activated in response to low temperature. Functions of those genes were confirmed through transgenic experiments and across peach cultivars, suggesting our dataset is a useful tool for elucidating regulatory factors that have not yet been clarified in relation to flavor and cold tolerance. Genome wide DNA methylation was induced by chilling and peaked at 7 d followed by a decline during 28 d cold storage. Reduction of gene expression was accompanied by major changes in the methylation status of their promoters, including PpACS1, PpAAT1, PpTPS3 and PpMADS2. ConclusionOur study revealed the mechanism for chilling-induced flavor loss of peach fruit through time-course transcriptome and DNA methylome analysis.

Analysis method of phytosterol constituents from vegetable to facilitate product development

In 2003, The United States Food and Drug Administration (USFDA) has approved food that contains at least 400 mg plant sterol eaten twice with meals for a daily total intake of at least 0.8 g, as part of a diet low in saturated fat and cholesterol. This recommendation is part of an effort to reduce the risk of heart disease. In this study, four types of phytosterol constituents which include stigmasterol, β-sitosterol, campesterol and stigmastanol have been used as standard reference since all the secondary metabolite constituents were reported widely found in vegetables. For analysis purposes, all the constituents were extracted either using solid-liquid extraction or liquid-liquid extraction. In the case of a solid sample, solid-liquid extraction with chloroform as a solvent is more suitable, while for a liquid sample, liquid-liquid extraction is more favourable. The detection of the phytosterol constituents was conducted via a gas chromatography-mass spectrometer (GCMS). The developed method will be useful for screening and selection of potential vegetables with phytosterol for food product development. In addition, the method could be used for monitoring batch to batch production of products in order to ensure quality.

Comprehensive Controller for Super Sonic Molecular Beam Gas Chromatograph Mass Spectrometer

This paper presents a new, comprehensive digital circuit used for the control of a novel gas chromatograph mass spectrometer (GC-MS) interface that is based on supersonic molecular beam (SMB). The circuit includes a Texas Instruments 150 MHz digital signal controller (DSC), high voltage amplifiers for 8 independent channels and 4 independent channels of high resolution pulse width modulation (PWM). The circuit, along with a sophisticated embedded program and a custom made personal computer (PC) application, control all aspects of the interface: smart filament emission-current stabilization, static and scanning mass-dependent ion-source voltages, transfer-line heater proportional integral differential (PID) controls with thermocouple feedbacks, on/off valves, relays and several peripheral device controls that enable the full operation of a turbo-molecular vacuum pump, and of gas flow and pressure controllers. All aspects of this comprehensive controller were successfully tested. The signal for the 450 Th ion (C32H66) for example increased by 123% which is a significant increase. It is obvious that correctly tuned dynamic voltages can guarantee the optimal signal for each mass.

Long-term profound investigation of Fenoxaprop-p-ethyl and indirect pesticide pollution in jute-cropped environmental ecosystem for dietary and ecological risk assessment.

Jute is a healthy vegetable due to its high content of carotenoids, vitamins, and minerals, in addition to its industrial utility. The purpose of this study was to look into the dissipation of fenoxaprop-p-ethyl and to track indirect sources of pesticide accumulation in jute ecosystems for three years in a row during tropical monsoon seasons. To avoid the intake of residues over approved limits, a rapid extraction technique was developed to evaluate the residues of this herbicide (Whip-Super 9% EC) in jute leaves, fiber, cropped soil, and water. A modified QuEChERS approach based on liquid chromatography and ultraviolet-visible (UV-VIS) detection was developed and successfully validated in accordance with SANCO requirements. Gas chromatography mass spectrometer (GC-MS) was used to examine fish and water samples from jute fields and retting pond for twenty widely-used multi-class pesticide contaminations from indirect sources. Relative standard deviations (RSD) (≤ 20) and recoveries (100-115%) are observed to be within acceptable ranges. In edible jute leaves, independent of season, first-order kinetics of dissipation was recorded, with half-lives ranging from 0.61 to 0.68days. Based on the findings of the risk assessment, it is feasible to conclude that the consumer health risks of ingesting jute leaves are insignificant, even on day zero, when used at the recommended amount, and that using jute bags for food packaging and storage is safe. But jute field water was found to be less polluted with indirect pesticides than water from a nearby jute retted pond. Fish samples from this jute retted pond were also analyzed and found to be 26% contaminated. The presence of quinalphos and chlorpyriphos in jute retting water and fish might pose a concern to consumer health and environmental ecosystems.

Phytochemical Content and Antibacterial Effect of Ethanolic and Methanolic Extracts of Pleurotus ostreatus Mushroom

Aims: Microbial resistance is a threat to the successful treatment of microbial infections. Mushrooms are known to possess antimicrobial and antioxidant potential which could be inhibitory to some pathogenic organisms. The aim was to assess the phytochemicals and antimicrobial potential of Pleurotus ostreatus extracts on some pathogenic organisms.&#x0D; Methodology: The study was conducted at the Bells University of Technology, Nigeria, between December 2019 and August 2020. A 10% dried powder of Pleurotus ostreatus was extracted in absolute ethanol and methanol and evaporated in a water bath at 50 oC. Extracts were reconstituted in dimethyl Sulfoxide (DMSO) at 12.5, 25, 50, and 100% respectively. Antibiotic effects of extracts were tested on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus saprophyticus by agar well diffusion method and compared with standard antibiotic discs. DMSO and the solvents served as positive and negative controls. Ethanolic extract was subjected to Gas Chromatography-Mass Spectrometer.&#x0D; Results: The extracts exhibited varying inhibitory effects on the organisms except on E coli at 12.5% ethanolic extract. The inhibition zones increased with extract concentration from 2-12 mm and 4-14 mm in ethanolic and methanolic extracts respectively. The inhibitory effect of standard antibiotics was higher 17-25 mm except for erythromycin (13-14 mm). Test organisms were resistant to Beta Lactams (augmentin, cefuroxime, and ceftazidime) and sensitive to Aminoglycoside (gentamicin), Fluoroquinolones (ofloxacin), Ciprofloxacin, and erythromycin. GC/MS revealed the presence of 30 organic compounds, amongst them were sugar, sugar alcohols, alkaloids, amines, fatty acids, esters, aldehydes, and alcohols. The most abundant were oleic acid (33.75%) and 9-octadecenoic acid (Z)-2-hydroxy-1- (21.21%). Phytochemicals are heterocyclic compounds found in natural products.&#x0D; Conclusion: P. ostreatus has been revealed to possess phytochemicals of medical relevance with potential for pharmacological application. The implication is that Pleurotus ostreatus extracts could serve as a lead to novel drug discoveries which could enhance health and nutritional well-being.