Microbial safety in food products is not always adequately controlled. Chemical antimicrobials which are recognized as hazards to human health are gradually replaced by natural antimicrobial ...compounds. In the current study, the antimicrobial activity against some Gram-positive and Gram- negative bacteria by the methanolic extract from rambutan fruit peels was evaluated using both in vitro (medium) and in situ (food matrices i.e. raw chicken breast and pangasius fillet fish) methods. Methanolic rambutan peel extract (lyophilized to powder with total phenolic content of 310 ± 14.5 mg GAE/g) with geraniin, ellagic acid, rutin, quercetin, and corilagin as main phenolic compounds was a potent inhibitor towards E. coli, V. campbellii, V. parahaemolyticus, V. anguillarum, P. aeruginosa, S. enteritidis, St. aureus, L. monocytogenes, and C. albicans using in vitro tests. In in situ tests, the extract inhibited S. enteritidis in raw chicken breast during 14 days of cold storage at 4 °C. Even though food matrices partly protected bacteria, the extract showed a 1.5 log CFU/g reduction of V. parahaemolyticus in fish during 10 days of cold storage. These results provide useful information on the utilization of rambutan fruit peel as natural antimicrobial agent in food products.
•Geraniin, rutin, quercetin, ellagic acid are main phenolics in rambutan peel extract.•They inhibited some gram negative and positive bacteria, and yeast in vitro.•These phenolics also inhibited S. enteritidis and V. parahaemolyticus in situ.•Rambutan peel extract has potential to be used as natural antimicrobial food agent.
The density-based clustering algorithm is a fundamental data clustering technique with many real-world applications. However, when the database is frequently changed, how to effectively update ...clustering results rather than reclustering from scratch remains a challenging task. In this work, we introduce IncAnyDBC, a unique parallel incremental data clustering approach to deal with this problem. First, IncAnyDBC can process changes in bulks rather than batches like state-of-the-art methods for reducing update overheads. Second, it keeps an underlying cluster structure called the object node graph during the clustering process and uses it as a basis for incrementally updating clusters wrt. inserted or deleted objects in the database by propagating changes around affected nodes only. In additional, IncAnyDBC actively and iteratively examines the graph and chooses only a small set of most meaningful objects to produce exact clustering results of DBSCAN or to approximate results under arbitrary time constraints. This makes it more efficient than other existing methods. Third, by processing objects in blocks , IncAnyDBC can be efficiently parallelized on multicore CPUs, thus creating a work-efficient method. It runs much faster than existing techniques using one thread while still scaling well with multiple threads. Experiments are conducted on various large real datasets for demonstrating the performance of IncAnyDBC.
In this paper, we have succeeded in preparing the Quantum dots Solar cells with the high efficiency of 4.22% based on Cu2+ ions doped on CdSe Quantum dots by Successive ionic layer absorption and ...reaction. There are significant effects of Cu2+ ions on optical, physical, chemical and photovoltaic features of QDSSCs. As a result, the current density of the QDSSCs increased dramatically from 12 mA/cm2 for pure CdSe QDs to 19.915 mA/cm2 for Cu2+ ions doped on pure CdSe QDs. In fact, Cu2+ dopant rise in the conduction band of pure CdSe QDs, reduces recombination, enhances the efficiency of high harvesting, improve the charge transfer and collection. In addition, Cu2+ dopant raise the level of the conduction band of pure CdSe QDs, which leads to reduce the charge recombination, enhance the light-harvesting efficiency and improve the charge diffusion and collection. In the same way, we also illustrated photoluminescence decay to determine the lifetime of excited electrons and Electrochemical Impedance Spectra to calculate dynamic resistances in QDSSCs and explain the obtained results.
Graphene oxide frameworks (GOFs) tailored with heteroatom-containing organic ligands were utilized for the efficient confinement of Pd nanoparticles (NPs) to achieve highly recyclable Pd catalysts ...for Suzuki-Miyaura cross-coupling reaction (SMC). The tailored GOFs were constructed using benzene-1,4-diboronic acid as a pillaring unit and N- and S- containing additional organic ligands to anchor Pd NPs. Highly dispersed Pd NPs with narrow size distribution were generated inside the gallery space of the GOFs. The presence of the anchoring ligands significantly enhanced the stability of Pd NPs via strong Pd−N and Pd−S bonds, leading to high activity and recyclability in the SMC reaction.
Graphic Abstract
Summary
Peel and seeds of red‐skinned passion fruit, mango, longan, rambutan, white‐flesh and red‐flesh dragon fruit were screened for their in vitro antioxidant activity, and determination of a ...detailed profile of phenolic compounds. Rambutan peel and mango seed extracts exhibited the highest total phenolic content and antioxidant activities (DPPH, ABTS and FRAP values). By using UPLC‐QTOF‐MS/MS analysis, the profiles of soluble and bound phenolics in the fruit by‐products were obtained. Ellagic acid, geraniin, quercetin hexoside, gallic and galloyshikimic acid were predominant in rambutan peel, whereas, mangiferin, ellagic acid and galloy(di)glucoside were the major phenolic compounds in mango seed. Main phenolic compounds in longan peel were ellagic acid, galloyldiglucoside, and gallic acid, while in dragon fruit peel this was isorhamnetin glycoside, isorhamnetin glucorhamoside. Meanwhile, rutin and quercetin hexoside were predominant in passion fruit peel. These findings contribute significantly to the database of phenolic profiles of by‐products of tropical fruits.
Tropical fruit by‐products are potential sources of phenolic compounds. In vitro antioxidant activity and phenolic content of fruit peel and seeds were determined. Using UPLC‐qTOF‐MS/MS, phenolic profiles of the fruit by‐products are presented.
Rambutan (Nephelium lappaceum L.) peel (RBP) is discarded as the main by‐product during processing of the fruit. Increasing attention is now paid to the valorization of RBP for the recovery of ...valuable compounds. Geraniin, ellagic acid, quercetin, and rutin are the main phenolic compounds found in methanolic RBP extract. Extracted rambutan peel powder (ERPP) is used to evaluate the oxidative stability of soybean oil stored at 4 and 30 °C in the dark and light and deep fried with potatoes at 160 °C. Tert‐butylhydroquinone (100 µg g−1 oil, TBHQ) serves as positive control. Oil supplemented with ERPP of 1000 µg gallic acid equivalents (GAE) g−1 of oil shows positive effects on the retardation of the oxidation process during storage in comparison with oil without addition. During deep frying, either ERPP (1000 µg GAE g−1) or TBHQ retards the lipid oxidation of oil. Levels of thiobarbituric acid reactive substances of potatoes fried in oil fortified with the extract and TBHQ (0.4–0.59 µg g−1) are much lower than those without the extract (1.31 ± 0.10 µg g−1) (p < 0.05). Therefore, RBP extract exhibits favorable antioxidant effects and can be used for effectively inhibiting lipid oxidation in oil during storage and deep frying.
Practical Applications: An extract from rambutan fruit peel containing phenolic compounds, that is, geraniin, ellagic acid, rutin, and quercetin showed promising results to be used as potential antioxidants in soybean oil during deep frying. Both oxidation of the frying oil as well as the oxidation of the food product, that is, potatoes were inhibited. These results demonstrated that rambutan fruit peel extract can be used as a natural antioxidant in frying oil to replace synthetic antioxidants, that is, TBHQ.
Flowchart of antioxidant activity of phenolic compounds from rambutan peel extract during oil storage and deep frying.
Purpose This study aims to analyse the role of the financial and accounting expertise of the chief executive officer (CEO) on financial reporting quality (FRQ) in an emerging economy. ...Design/methodology/approach This study is based on data collected from a large sample of all non-financial companies listed on Vietnamese stock exchanges during the period 2016–2020 with 2,435 observations. FEM-ROBUST standard errors regression model is used to examine the relationship between the financial, accounting expertise of CEOs and FRQ through earnings management by discretionary accruals. Findings The results show that CEOs with financial and accounting expertise have more influence and intervention on earnings management and thus adversely affect FRQ. This behaviour is explained by the fact that CEOs not only have a firm grasp of financial and accounting policies but also know the tricks to interfere with earnings management. Moreover, in the context of emerging economies, CEOs’ awareness and management level are still limited and legal sanctions are not yet strict, so when they have power in their hands, CEOs immediately find ways to build a reputation to enhance the power and earnings for the CEOs themselves. Research limitations/implications The limitation of this study is first of all that the research data are not complete and rich because the companies are prohibited from disclosing information and the cooperation relationship is not close. Next is the new research in only one emerging market – Vietnam – so the generalizability is not high. Originality/value To the best of the authors’ knowledge, this is the first study to examine the impact of CEOs’ accounting and finance expertise on FRQ in an emerging economy, contributing to the existing literature regarding the scientific debates about CEOs, CEO characteristics, earnings management and FRQ.
Sarcopenia, a condition characterized by muscle mass decline, is one of the leading health problems in the elderly. This study determined the rate of sarcopenia according to criteria by Asian Working ...Group for Sarcopenia (AWGS) and related factors in elderly people. A community-based cross-sectional study was conducted in 632 people aged 60 years or over in Ho Chi Minh City. Data were collected through a predefined questionnaire and direct measurement. Sarcopenia was identified based on the Inbody 770 machine and AWGS criteria. The prevalence of sarcopenia was 32.0%. Participants with advanced age, low education, unemployment, low level of family economics and frailty were more likely to have sarcopenia. Among these, frailty had the highest impact on sarcopenia, with significantly higher odds of having sarcopenia found in participants with pre-frailty (OR = 4.80, 95% CI 2.75-8.38, p < 0.001) and frailty (OR = 21.16, 95% CI 8.96-49.97, p < 0.001). In contrast, BMI was inversely associated with sarcopenia. Sarcopenia is prevalent in the Vietnamese elderly. Apart from social demographic characteristics including age, education, employment and family economic status, frailty appeared to be an important risk factor. Early screening, referral, and treatment of sarcopenia among the elderly having a high risk of sarcopenia are recommended.
Historically, it had been widely accepted that the female mammalian ovary contained a limited number of oocytes that would reduce over time, without the possibility of replenishment. However, recent ...studies have suggested that female germline stem cells (FGSCs) could replenish the oocyte-pool in adults. The aim of this study was to isolate FGSCs from porcine ovaries and differentiate them into oocyte-like cells (OLCs). The FGSCs were successfully isolated from porcine ovarian tissue and cultured in vitro, in DMEM/F-12 medium supplemented with growth factors (EGF, FGF, GDNF, etc.) and a supplement (N21). These cells possessed spherical morphology and expressed specific germline characteristics (Vasa, Stella, Oct4, c-kit). By evaluating different conditions for in vitro differentiation of FGSCs, co-culturing the isolated FGSCs with MEF cells, under three-dimensional (3D) cell cultures, were shown to be optimal. FGSCs could successfully be differentiated into OLCs and reached about 70 µm in diameter, with a large number of surrounding somatic cells. Importantly, OLCs contained large nuclei, about 25–30 µm, with filamentous chromatin, similar to oocyte morphology, and expressed oocyte-specific markers (Gdf9, Zp2, SCP3, etc.) at the same level as oocytes. In conclusion, we successfully isolated FGSCs from porcine ovarian tissue and differentiated them into oocyte-like cells. This will provide a valuable model for studying a new, alternative source of oocytes.
The increasing number of studies on graphene membranes has indicated a great potential of graphene in separation applications. For the first time, this study demonstrates liquid permeation ...performance of a new graphene membrane that assembled functionalized graphene sheets. Functionalized graphene was synthesized from graphene dispersion based on a Bingel reaction with diethyl bromomalonate, and employed to prepare an assembled membrane using a vacuum filtration method. Thus prepared membrane was subjected to permeation tests using four solvents (hexane, acetone, methanol and water). The chemical functionalization led to two interesting consequences: i) Even a relatively minor extent of functionalization dramatically altered the chemical selectivity of the membrane, and ii) the permeability of the membrane was greatly enhanced, which plausibly arose from the less ordered stacking of the functionalized graphene sheets as compared to the pristine ones.
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