Biotechnological Production of Phenyllactic Acid and Biosurfactants from Trimming Vine Shoot Hydrolyzates by Microbial Coculture Fermentation

Coculture fermentations show advantages for producing food additives from agroindustrial wastes, considering that different specified microbial strains are combined to improve the consumption of mixed sugars obtained by hydrolysis. This technology dovetails with both the growing interest of consumers towards the use of natural food additives and with stricter legislations and concern in developed countries towards the management of wastes. The use of this technology allows valorization of both cellulosic and hemicellulosic fractions of trimming vine shoots for the production of lactic acid (LA), phenyllactic acid (PLA), and biosurfactants (BS). This work compares the study of the potential of hemicellulosic and cellulosic fractions of trimming vine shoots as cheaper and renewable carbon sources for PLA and BS production by independent or coculture fermentations. The highest LA and PLA concentrations, 43.0 g/L and 1.58 mM, respectively, were obtained after 144 h during the fermentation of hemicellulosic sugars and simultaneous saccharification and fermentation (SSF) carried out by cocultures of Lactobacillus plantarum and Lactobacillus pentosus. Additionally, cell-bond BS decreased the surface tension (ST) in 17.2 U; meanwhile, cell-free supernatants (CFS) showed antimicrobial activity against Salmonella enterica and Listeria monocytogenes with inhibition halos of 12.1?±?0.6 mm and 11.5?±?0.9 mm, respectively.     

Direct electrochemistry and electrochemical biosensing of glucose oxidase based on CdSe@CdS quantum dots and MWNT-modified electrode

The direct electron transfer of glucose oxidase (GOx) was achieved based on the immobilization of CdSe@CdS quantum dots on glassy carbon electrode by multi-wall carbon nanotubes (MWNTs)-chitosan (Chit) film. The immobilized GOx displayed a pair of well-defined and reversible redox peaks with a formal potential (E ^θ’) of ?0.459 V (versus Ag/AgCl) in 0.1 M pH 7.0 phosphate buffer solution. The apparent heterogeneous electron transfer rate constants (k _s) of GOx confined in MWNTs-Chit/CdSe@CdS membrane were evaluated as 1.56 s^?1 according to Laviron's equation. The surface concentration (Γ*) of the electroactive GOx in the MWNTs-Chit film was estimated to be (6.52?±?0.01)?×?10^?11?mol?cm^?2. Meanwhile, the catalytic ability of GOx toward the oxidation of glucose was studied. Its apparent Michaelis–Menten constant for glucose was 0.46?±?0.01 mM, showing a good affinity. The linear range for glucose determination was from 1.6?×?10^?4 to 5.6?×?10^?3?M with a relatively high sensitivity of 31.13?±?0.02 μA?mM^?1?cm^?2 and a detection limit of 2.5?×?10^?5?M (S/N=3).     

Expression,Purification, and Characterization of NADP+-Dependent Malic Enzyme from the Oleaginous Fungus Mortierella Alpina

Malic enzymes are a class of oxidative decarboxylases that catalyze the oxidative decarboxylation of malate to pyruvate and carbon dioxide, with concomitant reduction of NAD(P)⁺ to NAD(P)H. The NADP⁺-dependent malic enzyme in oleaginous fungi plays a key role in fatty acid biosynthesis. In this study, the malic enzyme-encoding complementary DNA (cDNA) (malE1) from the oleaginous fungus Mortierella alpina was cloned and expressed in Escherichia coli BL21 (DE3). The recombinant protein (MaME) was purified using Ni-NTA affinity chromatography. The purified enzyme used NADP⁺ as the cofactor. The K _m values for l-malate and NADP⁺ were 2.19?±?0.01 and 0.38?±?0.02 mM, respectively, while the V _max values were 147?±?2 and 302?±?14 U/mg, respectively, at the optimal condition of pH 7.5 and 33 °C. MaME is active in the presence of Mn²⁺, Mg²⁺, Co²⁺, Ni²⁺, and low concentrations of Zn²⁺ rather than Ca²⁺, Cu²⁺, or high concentrations of Zn²⁺. Oxaloacetic acid and glyoxylate inhibited the MaME activity by competing with malate, and their K _i values were 0.08 and 0.6 mM, respectively.     

Assay of mixtures of chlorpheniramine maleate,pyrilamine meleate and phenylpropanolamine hydrochloride in cold-allergy tablets by difference spectrophotometry

Mixtures of chlorpheniramine maleate (CPM) and phenylpropanolamine hydrochloride (PPA), with and without pyrilamine maleate (PRM), are assayed by u.v. difference spectrophotometry without prior separation. The spectra for CPM and PRM in solutions at pH 1 and pH 6 show differences whereas the spectra for PPA remain the same at pH 1 and 6. For PPA, quantitation is based on the spectral change on oxidation to benzaldehyde with metaperiodate; this oxidation does not affect CPM and PRM. Calibration plots are linear for 6.7–99.9 μg ml^?1 CPM (r = 0.9992), 12.7–50.6 μg ml^?1 PRM (r = 0.9997) and 25–115.3 μg ml^?1 PPA (r = 0.9980) in the presence of one another. Average recoveries (± RSD) from simulated PPA/CPM tablets were: PPA, 98.4 ± 0.4% (without PRM, n = 3), 99.8 ± 0.4% (with PRM, n = 5); CPM, 99.3 ± 0.6% (without PRM, n = 3), 99.2 ± 0.4% (with PRM, n = 5); and PRM, 99.5 ± 0.2% (in PPA/CPM/PRM tablets, n = 5). The method was successfully applied to commercial cold-allergy tablets containing these compounds.     

Simultaneous Determination of Buprenorphine, Norbuprenorphine and Naloxone in Human Plasma by LC-MS-MS

A novel sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS-MS) method simultaneously determined buprenorphine (BUP) and its active metabolite, norbuprenorphine (NBUP), and a coformulant, naloxone was developed, validated and applied successfully in humans. Buprenorphine-d ₄ and norbuprenorphine-d ₃ were used as the internal standard. The analysis was performed on a silica column, and the mobile phase was isocratic and composed of acetonitrile:2 mM ammonium formate in H2O (82:18, v/v). Mass spectrometry employed multiple reaction monitoring modes with transitions of m/z 468.1?C55.2 for BUP, 414.2?C101.2 for NBUP, 328.3?C310.3 for naloxone, 472.1?C59.2 for buprenorphine-d ₄ and 417.2?C101.2 for norbuprenorphine-d ₃. Lower limit of quantification (LLOQ) of the analytical method was 0.05 ng mL^?1 for BUP, 0.1 ng mL^?1 for NBUP and 0.025 ng mL^?1 for naloxone, respectively. The standard calibration curves of BUP, NBUP and naloxone were linear over the concentration range of 0.05?C20 ng mL^?1, 0.1?C20 ng mL^?1 and 0.025?C20 ng mL^?1, respectively. The precisions (RSD) and accuracies (RE) of LLOQ and other QC samples were in acceptable range, with RSD < 20% and RE ± 20% for LLOQ and RSD < 15% and RE within ±15% for QC samples. The method was accurate, precise and specific, and was applied to the pharmacokinetic study of buprenorphine in healthy volunteers.     

Production of Ultra-high Molecular Weight Poly-γ-Glutamic Acid with Bacillus licheniformis P-104 and Characterization of its Flocculation Properties

A novel strain of Bacillus licheniformis P-104 was isolated from Chinese soybean paste to produce a bioflocculant. The bioflocculant was confirmed as ultra-high molecular weight poly-γ-glutamic acid (γ-PGA) using Fourier transform infrared spectrum, high-performance liquid chromatography, and gel permeation chromatography with multi-angle laser light scattering. The production technology and flocculation properties of γ-PGA were investigated. By fed-batch fermentation in a 7-L bioreactor, the maximum γ-PGA yield reached 41.6 g L^?1 with a productivity rate of 1.07 g L^?1 h^?1. The flocculating activity of γ-PGA for kaolin suspension was 33.5?±?1.6 1/OD under the optimized flocculation conditions (6 mM Ca²⁺, 1.5 mg L^?1 γ-PGA, and pH 6.0). The optimized dosage of γ-PGA for flocculation was just about 30 % of that of reported γ-PGA produced by other strains. Moreover, the flocculation activity of γ-PGA produced by strain P-104 was much higher than commercial γ-PGA with the molecular weight ranging 200–500 kDa and 1,500–2,500 kDa. This study provided a promising strain and an efficient method for production of ultra-high molecular weight γ-PGA which could be used as a potential green bioflocculant.     

Microbial Fed-batch Production of 1,3-Propanediol Using Raw Glycerol with Suspended and Immobilized Klebsiella pneumoniae

The production of 1,3-propanediol (1,3-PD) was investigated with Klebsiella pneumoniae DSM 4799 using raw glycerol without purification obtained from a biodiesel production process. Fed-batch cultures with suspended cells revealed that 1,3-PD production was more effective when utilizing raw glycerol than pure glycerol (productivity after 47 h of fermentation, 0.84 g?L^?1?h^?1 versus 1.51 g?L^?1?h^?1 with pure and raw glycerol, respectively). In addition, more than 80 g/L of 1,3-PD was produced using raw glycerol; this is the highest 1,3-PD concentration reported thus far for K. pneumoniae using raw glycerol. Repeated fed-batch fermentation with cell immobilization in a fixed-bed reactor was performed to enhance 1,3-PD production. Production of 1,3-PD increased with the cycle number (1.06 g?L^?1?h^?1 versus 1.61 g?L^?1?h^?1 at the first and fourth cycle, respectively) due to successful cell immobilization. During 46 cycles of fed-batch fermentation taking place over 1,460 h, a stable and reproducible 1,3-PD production performance was observed with both pure and raw glycerol. Based on our results, repeated fed batch with immobilized cells is an efficient fermentor configuration, and raw glycerol can be utilized to produce 1,3-PD without inhibitory effects caused by accumulated impurities.     

Biodiesel Residual Glycerol Metabolism by Klebsiella pneumoniae: Pool of Metabolites Under Anaerobiosis and Oxygen Limitation as a Function of Feeding Rates

The metabolism of residual glycerol from biodiesel synthesis by Klebsiella pneumoniae BLh-1 was investigated in this study. Batch and fed-batch cultivations were performed in bioreactors under anaerobic and oxygen limitation conditions. Results of batch cultivations showed that the main product was 1,3-propanediol (1,3-PD) in both conditions, although the higher yields and productivities (0.46 mol mol^?1 glycerol and 1.22 g?L^?1?h^?1, respectively) were obtained under anaerobic condition. Large amounts of ethanol were also produced under batch anaerobic condition, peaking at 12.30 g?L^?1. Batch cultivations under oxygen limitation were characterized by faster growth kinetics, with higher biomass production but lower conversions of glycerol into 1,3-PD, with yields and productivities of 0.33 mol mol^?1 glycerol and 0.99 g?L^?1?h^?1, respectively. The fed-batch cultivations were carried out in order to investigate the effects of feeding of raw glycerol on cells. Fed-batch under anaerobiosis showed that 1,3-PD and ethanol concentrations increased with the feeding rate, with maximal productions of 26.12 and 19.2 g?L^?1, respectively. The oxygen limitation conditions diverted the bacterium metabolism to an elevated lactic acid formation, reaching 59 g?L^?1 in higher feeding rates of glycerol, but lowering the production of ethanol.     

Enzymatic Hydrolysis and Fermentation of Pretreated Cashew Apple Bagasse with Alkali and Diluted Sulfuric Acid for Bioethanol Production

The aim of this work was to optimize the enzymatic hydrolysis of the cellulose fraction of cashew apple bagasse (CAB) after diluted acid (CAB-H) and alkali pretreatment (CAB-OH), and to evaluate its fermentation to ethanol using Saccharomyces cerevisiae. Glucose conversion of 82?±?2 mg/g CAB-H and 730?±?20 mg/g CAB-OH was obtained when 2% (w/v) of solid and 30 FPU/g bagasse was used during hydrolysis at 45 °C, 2-fold higher than when using 15 FPU/g bagasse, 44?±?2 mg/g CAB-H, and 450?±?50 mg/g CAB-OH, respectively. Ethanol concentration and productivity, achieved after 6 h of fermentation, were 20.0?±?0.2 g L^?1 and 3.33 g L^?1 h^?1, respectively, when using CAB-OH hydrolyzate (initial glucose concentration of 52.4 g L^?1). For CAB-H hydrolyzate (initial glucose concentration of 17.4 g L^?1), ethanol concentration and productivity were 8.2?±?0.1 g L^?1 and 2.7 g L^?1 h^?1 in 3 h, respectively. Hydrolyzates fermentation resulted in an ethanol yield of 0.38 and 0.47 g/g glucose with pretreated CAB-OH and CAB-H, respectively. Ethanol concentration and productivity, obtained using CAB-OH hydrolyzate, were close to the values obtained in the conventional ethanol fermentation of cashew apple juice or sugar cane juice.     

Determination of Meserine,a new candidate for Alzheimer’s disease in mice brain by liquid chromatography-tandem mass spectrometry and its application to a pharmacokinetic and tissue distribution study

A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of Meserine ((?)-meptazinol phenylcarbamate), a novel potent inhibitor of acetylcholinesterase (AChE), was developed, validated, and applied to a pharmacokinetic study in mice brain. The lower limit of quantification (LLOQ) was 1 ng mL^?1 and the linear range was 1–1,000 ng mL^?1. The analyte was eluted on a Zorbax SB-Aq column (2.1?×?100 mm, 3.5 μm) with the mobile phase composed of methanol and water (70:30, v/v, aqueous phase contained 10 mM ammonium formate and 0.3 % formic acid) using isocratic elution, and monitored by positive electrospray ionization in multiple reaction monitoring (MRM) mode. The flow rate was 0.25 mL min^?1. The injection volume was 5 μL and total run time was 4 min. The relative standard deviation (RSD) of intraday and interday variation was 2.49–7.81 and 3.01–7.67 %, respectively. All analytes were stable after 4 h at room temperature and 6 h in autosampler. The extraction recoveries of Meserine in brain homogenate were over 90 %. The main brain pharmacokinetic parameters obtained after intranasal administration were T _max?=?0.05 h, C _max?=?462.0?±?39.7 ng g^?1, T _1/2?=?0.4 h, and AUC_(0-∞)?=?283.1?±?9.1 ng h g^?1. Moreover, Meserine was distributed rapidly and widely into brain, heart, liver, spleen, lung, and kidney tissue. The method is validated and could be applied to the pharmacokinetic and tissue distribution study of Meserine in mice.     

Endopolysaccharides from Ganoderma resinaceum, Phlebia rufa, and Trametes versicolor Affect Differently the Proliferation Rate of HepG2 Cells

Fungi have been used for medicinal purposes for long time by Asian countries, being a putative source of powerful new phytopharmaceuticals such as polysaccharides. The aim of this study was to extract endopolysaccharides (IPS) from Ganoderma resinaceum, Phlebia rufa, and Trametes versicolor, grown under submerged culture, to compare crude IPS production, total carbohydrate, and protein yield, and to study the effect of these IPS on HepG2 cells proliferation rate. Total biomass produced by G. resinaceum, P. rufa, and T. versicolor was (in gram per liter) 3.32?±?0.80, 5.42?±?0.58, and 4.2?±?1.29 and the IPS yield (as the biomass percent) was 9.9?±?0.05, 29.0?±?6.3, and 9.1?±?3.1 %, respectively. Characterization of IPS has shown different proportion between total sugar and protein being, on average 6.04, 10.74, and 22.62, for G. resinaceum, T. versicolor, and P. rufa, respectively. The IPS effect, at 50, 100, and 200 μg?mL^?1 on HepG2 cell growth and viability was negligible for G. resinaceum and P. rufa but, in the case of T. versicolor, 200 μg?mL^?1 of IPS evoked 40 % reduction on cell growth. The results suggest that the intracellular polysaccharides from T. versicolor are a potential source for bioactive molecules with anti-proliferative properties.     

Enhanced Production of Poly-γ-glutamic Acid by <Emphasis Type="Italic">Bacillus licheniformis</Emphasis> TISTR 1010 with Environmental Controls

Bacillus licheniformis TISTR 1010 was used for glutamic acid-independent production of poly-γ-glutamic acid (γ-PGA). A fed-batch production strategy was developed involving feedings of glucose, citric acid, and ammonium chloride at specified stages of the fermentation. With the dissolved oxygen concentration controlled at ≥50% of air saturation and the pH controlled at ~7.4, the fed-batch operation at 37 °C afforded a peak γ-PGA concentration of 39.9 ± 0.3 g L^?1 with a productivity of 0.926 ± 0.006 g L^?1 h^?1. The observed productivity was nearly threefold greater than previously reported for glutamic acid-independent production using the strain TISTR 1010. The molecular weight of γ-PGA was in the approximate range of 60 to 135 kDa.     

Control of the Harmful Alga Microcystis aeruginosa and Absorption of Nitrogen and Phosphorus by Candida utilis

This study is aimed at controlling eutrophication through converting the nutrients such as nitrogen and phosphorus into microbial protein and simultaneously inhibiting the growth of Microcystis aeruginosa by Candida utilis. C. utilis and M. aeruginosa (initial cell density was 2.25?×?10⁷ and 4.15?×?10⁷ cells·mL^?1) were cultured together in the absence or presence of a carbon source (glucose) during a 10-day experiment. In the absence of carbon source, the measured removal efficiencies of NH₄ ⁺–N and PO₄ ^3?–P were 41.39?±?2.19 % and 82.93?±?3.95 %, respectively, at the second day, with the removal efficiency of 67.82?±?2.29 % for M. aeruginosa at the fourth day. In contrast, the removal efficiencies of NH₄ ⁺–N and PO₄ ^3?–P were increased to 87.45?±?4.25 % and 83.73?±?3.55 %, respectively, while the removal efficiency of M. aeruginosa decreased to 37.89?±?8.41 % in the presence of the carbon source (C/N?=?2:1). These results showed that the growth of M. aeruginosa was inhibited by C. utilis. Our finding sheds light on a novel potential approach for yeast to consume nutrients and control harmful algal during bloom events.     

Performance and Bacterial Population Composition of an n-Hexane Degrading Biofilter Working Under Fluctuating Conditions

In this work, several conditions of pH and inlet load (IL) were applied to a scale laboratory biofilter treating n-hexane vapors during 143 days. During the first 79 days of operation (period 1, P1), the system was fed with neutral pH mineral medium (MM) and the IL was progressively decreased from 177 to 16 g m^?3 h^?1. A maximum elimination capacity (EC) of 30 g m^?3 h^?1 was obtained at an IL of 176.9?±?9.8 g m^?3 h^?1. During the following 64 days (period 2, P2), acidic conditions were induced by feeding the biofilter with acidic buffer solution and pH 4 MM in order to evaluate the effect of bacterial community changes on EC. Within the acidic period, a maximum EC of 54 g m^?3 h^?1 (IL 132.3?±?13 g m^?3 h^?1) was achieved. Sequence analysis of 16S rDNA genes amplified from the consortium revealed the presence of Sphingobacteria, Actinobacteria, and α-, β- and γ-Proteobacteria. An Actinobacteria of the Mycobacterium genus had presence throughout the whole experiment of biofiltration showing resistance to fluctuating pH and IL conditions. Batch tests confirm the bacterial predominance and a negligible contribution of fungi in the degradation of n-hexane.     

In vitro studies of carbon fiber microbiosensor for dopamine neurotransmitter supported by copper-graphene oxide composite

A composite was prepared from copper and graphene oxide (Cu-GO) by in-situ chemical reduction of a mixture containing GO and Cu(II) ions with potassium borohydride. The morphology and structure of the composite were confirmed by various physicochemical techniques. The materials were used in a tyrosinase-based microbiosensor where the enzyme is immobilized in a biocompatible matrix consisting of poly(ortho-phenylene diamine) and Cu-GO. The composite was deposited on the surface of an 8-μm thick carbon fiber microelectrode. The role of each component in the sensing layer was systematically investigated with respect to the analytical performance of the system. In its optimal configuration, the biosensor demonstrated (a) a sensitivity of 6.1?±?3 nA mM^-1 dopamine (DA), (b) a linear response to DA (with a Michaelis-Menten constant of 0.29?±?0.03 mM), (c) good selectivity over ascorbic acid and uric acid, and (d) a high blocking capacity (112.2?±?2 mM) for ascorbic acid.

HPLC Analysis and Pharmacokinetic Study of Paeoniflorin after Intravenous Administration of a New Frozen Dry Powder Formulation in Rats

A simple and specific high performance liquid chromatographic (HPLC) method with UV detection using picroside II as the internal standard was developed and validated to determine the concentration of paeoniflorin in rat plasma and study its pharmacokinetics after an single intravenous administration of 40 mg kg^?1 paeoniflorin to Wistar rats. The analytes of interest were extracted from rat plasma samples by ethyl acetate after acidification with 0.05 mol L^?1 NaH₂PO₄ solution (pH 5.0). Chromatographic separation was achieved on an Agilent XDB C₁₈ column (250 × 4.6 mm I.D., 5 μm) with a Shim-pack GVP-ODS C₁₈ guard column (10 × 4.6 mm I.D., 5 μm) using a mobile phase consisting of acetonitrile–water–acetic acid (18:82:0.4, v/v/v) at a flow rate of 1.0 mL min^?1. The UV detection was performed at a wavelength of 230 nm. The linear calibration curves were obtained in the concentration range of 0.05–200.0 μg mL^?1 in rat plasma with the lower limit of quantification (LLOQ) of 0.05 μg mL^?1. The intra- and inter-day precisions in terms of % relative standard deviation (RSD) were lower than 5.7 and 8.2% in rat plasma, respectively. The accuracy in terms of % relative error (RE) ranged from ?1.9 to 2.6% in rat plasma. The extraction recoveries of paeoniflorin and picroside II were calculated to be 69.7 and 56.9%, respectively. This validated method was successfully applied to the pharmacokinetic study of a new paeoniflorin frozen dry power formulation. After single intravenous administration, the main pharmacokinetic parameters t _1/2, AUC_0-∞, CL_TOT, V _Z, MRT_0-∞ and V _ss were 0.739 ± 0.232 h, 43.75 ± 6.90 μg h mL^?1, 15.50 ± 2.46 L kg^?1 h^?1, 1.003 ± 0.401 L kg^?1, 0.480 ± 0.055 h and 0.444 ± 0.060 L kg^?1, respectively.     

Chemical composition,antioxidant and antimicrobial potential of essential oils from different parts of <Emphasis Type="Italic">Daphne mucronata</Emphasis> Royle

This research work was executed to determine chemical composition, anti-oxidant and anti-microbial potential of the essential oils extracted from the leaves and stem of Daphne mucronata Royle. From leaves and stem oils fifty-one different constituents were identified through GC/MS examination. The antioxidant potential evaluated through DPPH free radical scavenging activity and %-inhibition of peroxidation in linoleic acid system. The stem’s essential oil showed the good antioxidant activity as compared to leaves essential oil. Results of Antimicrobial activity revealed that both stem and leaves oils showed strong activity against Candida albicans with large inhibition zone (22.2?±?0.01, 18.9?±?0.20 mm) and lowest MIC values (0.98?±?0.005, 2.44?±?0.002 mg/mL) respectively. Leaves essential was also active against Escherichia coli with inhibition zone of 8.88?±?0.01 mm and MIC values of 11.2?±?0.40 mg/mL. These results suggested that the plant’s essential oils would be a potential cradle for the natural product based antimicrobial as well as antioxidant agents.

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Simultaneous Determination of Escin Ia and Its Isomer Isoescin Ia by LC�CMS�CMS: Application to a Pharmacokinetic Study of Escin Ia in Rats

A rapid and sensitive LC?CMS?CMS method for the simultaneous determination of escin Ia and isoescin Ia in rat plasma, urine, feces and bile samples was developed and validated. Analytes and telmisartan [internal standard (IS)] were extracted by solid-phase extraction on C₁₈ cartridges. Components in the extract were separated on an HC-C₁₈ column (5 ??m, 150 × 4.6 mm i.d.) using 10 mM ammonium acetate?Cmethanol?Cacetonitrile (40:30:30, v/v/v) as the mobile phase. The method demonstrated good linearity from 5 ng mL^?1 (LLOQ) to 1,500 ng mL^?1 for both escin Ia and isoescin Ia. Intra- and inter-day precision measured as RSD was within ±15%. Recoveries and matrix effects of both escin Ia and isoescin Ia were satisfactory in all four matrices examined. The method was successfully applied to a pharmacokinetic study in Wistar rats after a single intravenous administration of escin Ia at the dose of 1.0 mg kg^?1.     

In Vitro Studies on the Relationship Between the Antioxidant Activities of Some Berry Extracts and Their Binding Properties to Serum Albumin

The aim of this study was to investigate the possibility to use the bioactive components from cape gooseberry (Physalis peruviana), blueberry (Vaccinium corymbosum), and cranberry (Vaccinium macrocarpon) extracts as a novel source against oxidation in food supplementation. The quantitative analysis of bioactive compounds (polyphenols, flavonoids, flavanols, carotenoids, and chlorophyll) was based on radical scavenging spectrophometric assays and mass spectrometry. The total phenolic content was the highest (P?<?0.05) in water extract of blueberries (46.6?±?4.2 mg GAE/g DW). The highest antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and Cupric reducing antioxidant capacity were in water extracts of blueberries, showing 108.1?±?7.2 and 131.1?±?9.6 μMTE/g DW with correlation coefficients of 0.9918 and 0.9925, and by β-carotene linoleate assay at 80.1?±?6.6 % with correlation coefficient of 0.9909, respectively. The water extracts of berries exhibited high binding properties with human serum albumin in comparison with quercetin. In conclusion, the bioactive compounds from a relatively new source of gooseberries in comparison with blueberries and cranberries have the potential as food supplementation for human health. The antioxidant and binding activities of berries depend on their bioactive compounds.     

Human Saliva-Based Quantitative Monitoring of Clarithromycin by Flow Injection Chemiluminescence Analysis: A Pharmacokinetic Study

Human saliva quantitative monitoring of clarithromycin (CLA) by chemiluminescence (CL) with flow injection analysis was proposed for the first time, which was based on the quenching effect of CLA on luminol–bovine serum albumin (BSA) CL system with a linear range from 7.5?×?10^?4 to 2.0 ng/ml. This proposed approach, offering a maximum sample throughput of 100 h^?1, was successfully applied to the quantitative monitoring of CLA levels in human saliva during 24 h after a single oral dose of 250 mg intake, with recoveries of 95.2～109.0 % and relative standard deviations lower than 6.5 % (N?=?7). Results showed that CLA reached maximum concentration of 2.28?±?0.02 μg/ml at approximately 3 h, and the total elimination ratio was 99.6 % in 24 h. The pharmacokinetic parameters including absorption rate constant (0.058?±?0.006 h^?1), elimination rate constant (0.149?±?0.009 h^?1) and elimination half-life time (4.66?±?0.08 h) were obtained. A comparison of human saliva and urine monitoring was also given. The mechanism study of BSA–CLA interaction revealed the binding of CLA to BSA is an entropy driven and spontaneous process through hydrophobic interaction, with binding constant K _BSA–CLA of 4.78?×?10⁶ l/mol and the number of binding sites n of 0.82 by flow injection–chemiluminescence model. Molecular docking analysis further showed CLA might be in subdomain IIA of BSA, with K _BSA–CLA of 6.82?×?10⁵ l/mol and ΔG of ?33.28 kJ/mol.