Reversible cardiac function and left ventricular hypertrophy in a Chinese man with mitochondrial myopathy: a case report.

BACKGROUND: Mitochondrial myopathies (MMs) are a group of multi-system diseases caused by abnormalities in mitochondrial DNA (mtDNA) or mutations of nuclear DNA (nDNA). The diagnosis of mitochondrial myopathy (MM) is reliant on the combination of history and physical examination, muscle biopsy, histochemical studies, and next-generation sequencing. Patients with MMs have diverse clinical manifestations. In the contemporary literature, there is a paucity of reports on cardiac structure and function in this rare disease. We report a Chinese man with MM accompanied with both acute right heart failure and left ventricular hypertrophy. CASE PRESENTATION: A 49-year-old man presented with clinical features suggestive of MM, i.e., ophthalmoparesis, weakness of the pharyngeal and extremity muscles, and respiratory muscles which gradually progressed to respiratory insufficiency. He had a family history of mitochondrial myopathy. He had increased levels of serum creatine kinase and lactate. Muscle biopsy of left lateral thigh revealed 8% ragged red fibers (RRF) and 42% COX-negative fibers. Gene sequencing revealed a novel heterozygote TK2 variant (NM_001172644: c.584T>C, p.Leu195Pro) and another heterozygous variant (NM_004614.4:c.156+958G>A; rs1965661603) in the intron of TK2 gene. Based on these findings, we diagnosed the patient as a case of MM. Echocardiography revealed right heart enlargement, pulmonary hypertension, left ventricular hypertrophy, and thickening of the main pulmonary artery and its branches. The patient received non-invasive ventilation and coenzyme Q10 (CoQ10). The cardiac structure and function were restored at 1-month follow-up. CONCLUSIONS: This is the first report of reversible cardiac function impairment and left ventricular hypertrophy in a case of adult-onset MM, nocturnal hypoxia is a potential mechanism for left ventricular hypertrophy in patients with MM.

Preparation of carbon self-doped g-C3N4 for efficient degradation of bisphenol A under visible light irradiation.

In this study, visible-light-driven carbon self-doped graphitic carbon nitride photocatalyst was fabricated by a facile method with urea and ammonium citrate, and used for photodegradation of bisphenol A (BPA) in the aqueous environment. The experiments indicated that the prepared photocatalyst (C0.02CN) showed high catalytic activity, and 96.0%, 93.2%, and 95.5% BPA could be photodegraded in 150 min under pH 3, 6, and 11, respectively. The photocatalytic degradation rate (0.018 min-1) and mineralization (27.6%) of C0.02CN for BPA were about 6.7 and 3.5 times higher than those of the g-C3N4 (0.0027 min-1, 7.87%), respectively. C0.02CN had high reusability with a photodegradation efficiency of 84.5% for BPA after 3 cycles. Moreover, C0.02CN introduced additional carbon atoms, which generated C-O-C bonds in the g-C3N4 lattice. In contrast to g-C3N4, carbon doping enhanced the visible light absorption range of C0.02CN, reduced its band gap, and improved the separation efficiency of photogenerated electron-hole pairs. Radical quenching experiment and ESR results revealed that superoxide radicals (•O2-) and photogenerated holes (h+) acted as important parts in the high photodegradation activity under visible light irradiation. This work puts forward a one-pot strategy for the preparation of carbon self-doped g-C3N4, displacing the high-energy consuming and complicated preparation technology with promising industrial applications.

Adsorption of ionic and neutral pharmaceuticals and endocrine-disrupting chemicals on activated carbon fiber: batch isotherm and modeling studies.

Activated carbon fiber (ACF) has received increasing attention as an adsorbent due to its excellent surface properties. However, the adsorption mechanism of ACF for micropollutants, especially those in ionic forms, has not been sufficiently characterized to date. Therefore, the adsorption property of ACF was characterized using isotherm experiments and linear free energy relationship (LFER). For the experiments, adsorption affinities of thirty-five chemicals, i.e., pharmaceuticals and endocrine-disrupting chemicals, on ACF were estimated. Afterward, the adsorption affinities were used as dependent variables to build the LFER modeling. Finally, three isolated models for each chemical species, i.e., cations, anions, and neutrals, and a comprehensive model for the whole dataset were developed. The LFER results revealed that the models for anionic and neutral compounds have high predictabilities in R2 of 0.97 and 0.96, respectively, while that for cations has a slightly lower R2 of 0.72. In the comprehensive model including cationic, anionic, and neutral compounds, the accuracy of it is 0.81. From the developed LFER model based on the whole dataset, the adsorption mechanisms of ACF for the selected substances could be interpreted, in which the terms of hydrophobic interaction, hydrogen bonding basicity, and anionic Coulombic force of the compounds were identified as the predominant interactions with ACF.

Accumulation characteristics and ecological implications of heavy metals in surface sediments of the Mwanza Gulf, Lake Victoria.

The distribution of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn and their fraction characteristics (except Hg) were investigated in surface sediments of the Mwanza Gulf, Lake Victoria. The ecological risks, bioavailability, and mobility of the metals were also evaluated by using enrichment factor (EF), contamination factor (Cf), geo-accumulation index (Igeo), potential ecological risk index (RI), risk assessment code (RAC), individual contamination factor (ICF), and global contamination factor (GCF). Results showed that there were moderate accumulations of heavy metals in sediments from the southern part of the gulf. The mean Cf of heavy metals ranged from 1.19 (Ni) to 2.85 (Hg) suggesting moderate contamination of heavy metals in the sediments while Igeo results showed that the sediments are mainly contaminated by As, Cr, and Hg. The average potential ecological risk of heavy metals in sediments of the Mwanza Gulf is at moderate level (RI 205.49). Hg and Cd posed considerable or moderated risks with mean ecological risk of 114.18 and 44.16, which accounted for 51.08% and 21.54% of the total RI, respectively. High bioavailability and mobility of heavy metals were found in sediments near Mwanza city, particularly Zn and Cd, of which the bioavailability risks were at medium to high levels. Given the biological and environmental importance of the Mwanza Gulf and Lake Victoria, emission paths and bioaccumulation of heavy metals through food webs should be studied carefully to ensure the safety of food and the health and well-being of humans.

Supplementing cholamine to diet lowers laying rate by promoting liver fat deposition and altering intestinal microflora in laying hens.

The effects of cholamine, a raw material for synthesis of some active lipids, are unknown in poultry. To address this, 180 52-wk-old Hyline laying hens were randomly divided into 3 groups (20 replicates per group with three hens per replicate). The control group and the treatment groups (treatment 1 and 2) were fed basal diet and the diet supplemented with 500 or 1,000 mg of cholamine per kilogram of the diet for 35 d, respectively. The data showed that supplementary cholamine significantly lowered egg production, daily feed intake, serum high-density lipoprotein cholesterol level, liver index, and the percentages of C15:0 and C20:0 in fatty acid composition of liver, significantly elevated hepatic triglyceride content, the ratio of villus height to crypt depth (P < 0.05), and the percentage of C18:2n-6 and the ratio of n-6 to n-3 polyunsaturated fatty acids in liver fat (P < 0.10). Moreover, supplementary cholamine altered the relative abundance of some intestinal bacteria with a decrease in the alpha biodiversity (P < 0.10). Additionally, transcriptome analysis on the livers of the treatment vs. the control groups identified 1,151 up- and 914 down-regulated differentially expressed genes (DEGs), and pathway analysis revealed that the suppressed Notch signaling pathway and the enhanced Oxidative phosphorylation pathway were enriched with DEGs. Particularly, fat absorption, transport and oxidative phosphorylation-related DEGs (e.g., FABP1, APOA4, and PCK1) were significantly induced, but fatty acid synthesis, and lipid package and secretion-related DEGs (e.g., FASN, SCD, and MTTP) were not. In conclusion, supplementary cholamine may lower egg production by promoting hepatic lipid deposition and reducing abundances of beneficial intestinal bacteria and microfloral biodiversity in laying hens.

Effect of extraction technique on chemical compositions and antioxidant activities of freeze-dried green pepper.

In this study, the yield, content of piperine, and antioxidant activity of pepper oleoresin obtained with the methods of maceration, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and ultrasound-MAE (UMAE) were analyzed, and the microstructure of pepper residue was observed. For the yield and piperine content, the UMAE method had the best extraction capacity among the four methods. While, the oleoresin obtained with maceration had the highest total phenolic content, and the antioxidant activity of the oleoresin obtained by maceration was higher than that of the extracts acquired by UAE, MAE, and UMAE, and a high positive correlation was observed between the antioxidant activity and total phenolic content of the oleoresin obtained by these extraction methods. The ideal parameters for UMAE were an 80-mesh particle size and a 1 g/10 mL solid-liquid ratio. The kinetic parameters and models of the UMAE extraction process were also compared using first- and second-order models. The second-order kinetic equation with the lowest root mean square deviation and highest adjusted correlation coefficient proved to be more suitable for describing the extraction kinetics of pepper oleoresin. This study showed that UMAE is a fast, efficient, and cost-effective technique for the extraction of green pepper oleoresin.

Status and changes of water quality in typical near-city zones of three East African Great Lakes in Tanzania.

Tanzania is the only country bordering all three transboundary East African Great Lakes, i.e., Lake Victoria, Lake Tanganyika, and Lake Nyasa (Lake Malawi). This study investigated the spatiotemporal variability of basic physicochemical parameters of nearshore surface waters in Mwanza Gulf (Lake Victoria), Kigoma Bay (Lake Tanganyika), and Wissmann Bay (Lake Nyasa). Water quality was evaluated using the water quality index (WQI) method. Results showed that N and P nutrient pollution was relatively severe in central and southern parts of Mwanza Gulf owing to external agricultural emissions and internal release associated with physically disturbed sediment resuspension. External inputs from inflowing surface runoffs from the city of Mwanza typically enhanced N loading in northern parts of the gulf during the rainy season. Poor water quality was found in central and southern parts of Mwanza Gulf, especially in the rainy season. Algal blooms and NH4+-N (total P and total N) were the main factors driving water quality degradation in the rainy (dry) season. Kigoma Bay and Wissmann Bay both had good water quality, except in river mouth areas in Lake Nyasa during the rainy season. The degradation in water quality was caused primarily by increased land-based nutrient and turbidity inputs. To respond to challenges associated with climate change and local socioeconomic development, long-term monitoring of the lacustrine environment and systematic limnological studies will be required, not only in the three bays but also more widely throughout the three lakes and their basins.

Acidosis in arterial blood gas testing is associated with clinical outcomes after endovascular thrombectomy.

Background: Despite recanalization, some of the patients undergoing endovascular thrombectomy (EVT) still suffer from unfavorable outcomes. Patients with poor prognoses are often accompanied by acidosis in arterial blood gas (ABG) testing. We, therefore, explored the ABG testing results in the early phase of recanalization and analyzed their association with poor prognosis. Patients and methods: We identified all patients with ischemic stroke and successful endovascular recanalization for anterior circulation vessel occlusion between June 2019 and May 2022. ABG testing was performed in all patients within 0-30 min and 8 h after endovascular therapy. We investigated the relationship between the ABG testing results with symptomatic intracerebral hemorrhage (sICH), hemicraniectomy, and mortality. Results: A total of 123 patients with stroke after endovascular thrombectomy were analyzed. Of those, eight (6.5%) patients had postinterventional sICH. Acidosis was associated with sICH. Decreased HCO 3 - levels and HCO 3 - levels at 8 h after EVT were independently related to a higher risk of sICH. Twelve (9.8%) patients underwent hemicraniectomy for postischemic malignant edema and similar results were found for hemicraniectomy. Increased lactate at 8 h after EVT and decreased HCO 3 - levels at 8 h after EVT were closely associated with hemicraniectomy. Twenty-two (17.9%) patients died within 3 months. Decreased HCO 3 - levels were independently related to mortality, as were decreased pH levels at 8 h after EVT and decreased HCO 3 - levels at 8 h after EVT. Conclusion: Acidosis is associated with clinical outcomes after endovascular therapy and may help to select patients with poor prognosis in the acute early phase of recanalization.

Effective adsorption of mercury by Zr(IV)-based metal-organic frameworks of UiO-66-NH2 from aqueous solution.

In this study, Zr-based metal-organic frameworks (MOFs) of UiO-66 and UiO-66-NH2 were synthesized and applied to removal of mercury from aqueous solution. The characterizations of UiO-66 and UiO-66-NH2 were examined by X-ray diffraction (XRD), scanning electron microscope (SEM), and thermogravimetric analysis (TGA). To investigate the adsorption properties of UiO-66-NH2 for mercury, the experiments of kinetics, isotherm, pH, temperature, and salt concentration were conducted, and the results were compared with those by UiO-66. The result showed that UiO-66-NH2 has a higher adsorption capacity for mercury than UiO-66. The maximum adsorption capacity of UiO-66-NH2 was 223.8 ± 17.8 mg g-1 at 313 K. The salt concentration of NaCl has a significant effect on the adsorption of mercury on UiO-66, while UiO-66-NH2 can maintain the stable adsorption capacity for mercury in the concentration range of 0.1-0.5 M NaCl. Adsorption thermodynamics result indicated that the adsorption process of mercury on UiO-66-NH2 was spontaneous and endothermic. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses showed that the mercury was successfully adsorbed on the surface of UiO-66-NH2 and amino functional group as a soft base played a major role to react with mercury during the adsorption process. Graphical abstract.

A novel strategy for Cr(VI) removal from aqueous solution via CYPH@IL101/chitosan capsule.

A novel adsorbent, chitosan capsule with filler of CYPH@IL101 (CYPH@IL101/chitosan capsule), was prepared using a summary process for the adsorption of Cr(VI) from aqueous solution. The effects of CYPH@IL101 content, pH, contact time, rotational speed and Cr(VI) concentration on the adsorption were studied. The results showed that the adsorption capacity of the chitosan capsule was benefit from the increase of CYPH@IL101 content. Besides, solution pH also played an important role in the adsorption process and the maximum adsorption capacity was achieved at pH 3. Kinetic studies suggested that the adsorption rate was controlled by the diffusion step at low rotational speed (50 r/min), but was controlled by chemical reaction at high rotational speed (150 and 250 r/min). Furthermore, the adsorption isotherms were studied by using Langmuir, Freundlich, BET, and Temkin models. The results demonstrated that the adsorption process fit Langmuir and TemKin models better, which indicated that the adsorption of Cr(VI) onto CYPH@IL101/chitosan capsule mainly depended on chemisorption and the active sites were uniformly distributed on the adsorbent surface. While, the maximum adsorption capacity obtained from Langmuir model was 104.38 mg/g. Finally, XPS and FTIR analyses revealed that Cr(VI) was adsorbed and then reduced to Cr(III) by CYPH@IL101/chitosan capsule.

The preparation of amorphous TiO2 doped with cationic S and its application to the degradation of DCFs under visible light irradiation.

An amorphous S-doping TiO2 catalyst [S-TiO2 (300)] with visible light catalytic activity was successfully prepared via a sol-gel method with low-temperature calcination (300 °C) using thiourea as the sulfur source. The S-TiO2 (300) catalyst showed great performance in degrading the recalcitrant pharmaceutical, diclofenac (DCF). 93% of the target pollutant DCF degraded in 4 h under visible light irradiation. Both the amorphous form of the catalyst and cationic S-doping (with a coordinated structure) contributed to narrowing the band gap. As a result, the photocatalytic activity of S-TiO2 (300) was significantly enhanced under visible light irradiation. In addition, oxidative species such as photogenic cavitation (h+), OH and O2- were proved to participate in the photodegradation process, attacking COOH group and NH bond, degraded DCF into low molecule organic gradually.

Unexpected Intracranial Hemorrhage and Death After Cranioplasty in a Patient With Massive Hemispheric Infarction.

The benefits and common complications of cranioplasty are often mentioned, but fatal complications are rarely documented. Here, the authors report a patient of intracranial hemorrhage and death after cranioplasty and discussed the possible mechanism. A 42-year-old man was admitted with the diagnosis of massive cerebral infarction in left fronto-temporo- parietal lobe, emergency surgery for decompressive large craniotomy and Encephalo-Myo-Synangiosis were performed. One year after surgery, cranioplasty was performed using a titanium mesh plate. Intraoperative cerebrospinal fluid leakage was occurred and dura mater was repaired using pieces of silk. During the postoperative anesthesia emergence, the patient had epileptic seizures and did not wake after surgery. The authors also observed about 150 mL bloody cerebrospinal fluid (CSF) in the subcutaneous vacuum drainage system within 2 hours. Emergency computed tomography of the brain showed epidural, subdural, subarachnoid hemorrhages in the postischemic area, the middle line left, and the brain stem swelling. The patient's family refused to immediately remove the titanium mesh plate. Finally, nonoperative treatment is invalid and the patient's neurological condition did not recover and he died 3 days after the surgery. In the authors' mind, patients with previous massive cerebral infarction and Encephalo-Myo-Synangiosis undergoing cranioplasty might be at heightened risk of a fatal event than other cranioplasty. Therefore, the patients should be paid more attention to prevent and treat the fatal complications.

Adsorptive removal of endocrine-disrupting compounds and a pharmaceutical using activated charcoal from aqueous solution: kinetics, equilibrium, and mechanism studies.

Bisphenol A (BPA), diethyl phthalate (DEP), and carbamazepine (CBZ) have been widely used in chemical and pharmaceutical fields, and their residues are detected in various environments. Therefore, to find a suitable method for removing the compounds from an aqueous solution, an adsorption method by granular activated charcoal (AC) was studied. To investigate the adsorption properties of AC, its kinetics, equilibrium, pH effects, and regeneration of AC were examined. Moreover, its surface properties (i.e., surface area, pore volume, functional groups, and surface charge) were characterized by N2 adsorption and desorption isotherm, Fourier transform infrared (FTIR), and zeta potential analyses. Experimental results show that AC has high removal efficiencies for the target compounds at the low initial concentration as well as high estimated adsorption capacities (qm) for DEP, BPA, and CBZ, whose values were 293.4 ± 18.8, 254.9 ± 16.2, and 153.3 ± 1.61 mg/g, respectively. In comparison with other adsorbents based on previously reported results, AC was shown to have generally higher removability for the three compounds than others. Moreover, it was observed that AC's ability to adsorb DEP and BPA was dependent on pH because of hydrolysis and ionization, respectively. Meanwhile, there is no pH effect for CBZ adsorption by AC. After 3 cycles of adsorption/desorption, AC still maintained 92, 100, and 82% of initial adsorption capacities for DEP, BPA, and CBZ, respectively. Therefore, the AC is an effective adsorbent for the removal of endocrine-disrupting chemicals and pharmaceuticals from aqueous solution.

Nontargeted Metabolomics for Phenolic and Polyhydroxy Compounds Profile of Pepper (Piper nigrum L.) Products Based on LC-MS/MS Analysis.

In the present study, nontargeted metabolomics was used to screen the phenolic and polyhydroxy compounds in pepper products. A total of 186 phenolic and polyhydroxy compounds, including anthocyanins, proanthocyanidins, catechin derivatives, flavanones, flavones, flavonols, isoflavones and 3-O-p-coumaroyl quinic acid O-hexoside, quinic acid (polyhydroxy compounds), etc. For the selected 50 types of phenolic compound, except malvidin 3,5-diglucoside (malvin), l-epicatechin and 4'-hydroxy-5,7-dimethoxyflavanone, other compound contents were present in high contents in freeze-dried pepper berries, and pinocembrin was relatively abundant in two kinds of pepper products. The score plots of principal component analysis indicated that the pepper samples can be classified into four groups on the basis of the type pepper processing. This study provided a comprehensive profile of the phenolic and polyhydroxy compounds of different pepper products and partly clarified the factors responsible for different metabolite profiles in ongoing studies and the changes of phenolic compounds for the browning mechanism of black pepper.

Study on the copper(II)-doped MIL-101(Cr) and its performance in VOCs adsorption.

The metal-organic framework (MOF) materials, MIL-101(Cr), and copper-doped MIL-101(Cr) (Cu@MIL-101(Cr)) were prepared through hydrothermal method and were used to remove volatile organic compounds (VOCs) in this study. Morphological characterization demonstrated that MIL-101(Cr) and Cu-3@MIL-101(Cr) were octahedral crystal, with specific surface area of 3367 and 2518 m2/g, respectively. The results of XRD, TG, and FTIR showed that the copper doping procedure would not alter the skeleton structure, but it would affect the crystallinity and thermal stability of MIL-101(Cr). Besides, MIL-101(Cr) and Cu-3@MIL-101(Cr) displayed good removal efficiencies on benzene sorption, and the maximum sorption capacity was 103.4 and 114.4 mg/g, respectively. In competitive adsorptions, the order of adsorption priority on Cu-3@MIL-101(Cr) was as follows: ethylbenzene > toluene > benzene. Hence, it could be concluded that MIL-101(Cr) and copper-doped MIL-101(Cr) demonstrated good performance in VOCs adsorption and showed a promising potential for large-scale applications in the removal of VOCs. Graphical abstract ᅟ.

Contribution of Polyphenol Oxidation, Chlorophyll and Vitamin C Degradation to the Blackening of Piper nigrum L.

Black pepper (Piper nigrum L.) is the most widely used spice in the world. Blackening is considered to be beneficial and important in the processing of black pepper because it contributes to its color and flavor. The purpose of this paper is to investigate polyphenol oxidation as well as the chlorophyll and vitamin C (VC) degradation in the blackening of Piper nigrum L. Black pepper was produced by four methods, and changes in polyphenols, chlorophyll and VC were studied by high performance liquid chromatography (HPLC) and ultraviolet-visible and visible (UV-Vis) spectrophotometry. The results show that polyphenol oxidase activity significantly decreased during the preparation of black pepper, and the concentrations of phenolic compounds, VC, and chlorophyll a and b also significantly decreased. Polyphenol oxidation and chlorophyll and VC degradation contribute to the blackening. A crude extract of phenolic compounds from black pepper was prepared by the system solvent method. The greater the polarity of the extraction solvent, the higher the extraction rates of the phenolic compounds and the total phenol content. Pepper phenolic compounds were analyzed by HPLC analysis.

Effects of maltose and lysine treatment on coffee aroma by flash gas chromatography electronic nose and gas chromatography-mass spectrometry.

BACKGROUND: Arabica coffee is a sub-tropical agricultural product in China. Coffee undergoes a series of thermal reactions to form abundant volatile profiles after roasting, so it loses a lot of reducing sugars and amino acids. Adding carbonyl compounds with amino acids before roasting could ensure the nutrition and flavour of coffee. The technology is versatile for the development of coffee roasting process. This investigation evaluates the effects of combining maltose and lysine (Lys) to modify coffee aroma and the possibly related mechanisms. Arabica coffee was pretreated with a series of solvent ratios of maltose and Lys with an identical concentration (0.25 mol L-1 ) before microwave heating. RESULTS: It was found that the combination of maltose and Lys significantly (P ≤ 0.05) influenced quality indices of coffee (pH and browning degree). Ninety-six aromatic volatiles have been isolated and identified. Twelve volatile profiles revealed the relationship between fragrance difference and compound content in coffee. Moreover, coffee aroma was modified by a large number of volatiles with different chemical classes and character. CONCLUSION: Thus, our results suggest that the combination of reagents changed overall aroma quality through a series of complex thermal reactions, especially the ratio of Lys/maltose over 2:1. © 2017 Society of Chemical Industry.

Elevated blood pressure is associated with higher prevalence of low visual acuity among adolescent males in Northeast China.

The purpose of this study is to track the trends of low visual acuity (VA) from 2005 to 2014, and to investigate its associations with systemic blood pressure (BP) components among adolescents in Northeast China. A total of 55320 students of Han nationality aged 13 to 18 years were included. There has been a significant increase in the prevalence of low VA, with 31.3% in 2005, 40.2% in 2010 and 43.4% in 2014. In multivariable-adjusted logistic regression models, each 1-mm Hg increment in systolic BP (SBP) was associated with 0.8% (95% confidence interval [CI]: 0.1-1.6%), 0.5% (95% CI: 0.1-0.9%) and 1.1% (95% CI: 0.6-1.6%) increased odds of low VA for males in 2005, 2010 and 2014; each 1-mm Hg increment in pulse pressure (PP) was associated with 1.6% (95% CI: 0.7-2.5%), 0.8% (95% CI: 0.4-1.2%) and 1.2% (95% CI: 0.7-1.7%) increased odds of low VA. Higher PP categories had greater odds for low VA compared with the reference group. Similar associations were not observed for females. We conclude that higher prevalence of low VA was significantly associated with higher SBP and PP in males. Furthermore, there was a dose-dependent association between the prevalence of low VA and the levels of PP.

Regulation of Black Pepper Inflorescence Quantity by Shading at Different Growth Stages.

Black pepper is a perennial plant that can bloom throughout the year. It is generally expected that pepper inflorescence quantity could be minimized at the nonfull-bloom stage. The objective of this study was to find an appropriate shading measure that could inhibit blooming at other growing stages except the full-bloom stage and did not cause any reduction in pepper yield and quality. In this study, pepper trees were shaded up to 15%, 30%, 60% and 75%, respectively, and the inflorescence quantity, photosynthetic characteristics, pepper yield and quality traits were investigated at every growing stage. The results showed that the effect of shading on pepper yield decreased as time progressed. Shading treatment did not alter the composition of piperine and volatile oil, but reduced the moisture content. Based on the correlation between photosynthetic parameter and inflorescence number, the appropriate shading intensities for regulating inflorescence quantity at different phenological stages were determined. Moreover, it was found that the regulation of inflorescence quantity could be achieved by controlling leaf temperature during recovery to filling period. This research outcome also will give us some guidelines to develop other management strategies that control leaf temperature and regulate inflorescence quantity to consequently improve pepper yield.

Contribution of Bacillus Isolates to the Flavor Profiles of Vanilla Beans Assessed through Aroma Analysis and Chemometrics.

Colonizing Bacillus in vanilla (Vanilla planifolia Andrews) beans is involved in glucovanillin hydrolysis and vanillin formation during conventional curing. The flavor profiles of vanilla beans under Bacillus-assisted curing were analyzed through gas chromatography-mass spectrometry, electronic nose, and quantitative sensory analysis. The flavor profiles were analytically compared among the vanilla beans under Bacillus-assisted curing, conventional curing, and non-microorganism-assisted curing. Vanilla beans added with Bacillus vanillea XY18 and Bacillus subtilis XY20 contained higher vanillin (3.58%±0.05% and 3.48%±0.10%, respectively) than vanilla beans that underwent non-microorganism-assisted curing and conventional curing (3.09%±0.14% and 3.21%±0.15%, respectively). Forty-two volatiles were identified from endogenous vanilla metabolism. Five other compounds were identified from exogenous Bacillus metabolism. Electronic nose data confirmed that vanilla flavors produced through the different curing processes were easily distinguished. Quantitative sensory analysis confirmed that Bacillus-assisted curing increased vanillin production without generating any unpleasant sensory attribute. Partial least squares regression further provided a correlation model of different measurements. Overall, we comparatively analyzed the flavor profiles of vanilla beans under Bacillus-assisted curing, indirectly demonstrated the mechanism of vanilla flavor formation by microbes.