High-performance Liquid Chromatography Profiles Research Articles

Proximate Composition, Comparative Phytochemical Analysis, and HPLC Profiling of Various Solvent Extracts of Anthocleista djalonensis Leaves

Choosing the right solvent in herbal preparation is very important for extracting bioactive compounds from medicinal plant, as it greatly affects the yield and quality of phytochemicals obtained. This study aimed to investigate the proximate composition, phytochemical analysis and HPLC profiling of various solvents extracts of Anthocleista djalonensis leaves, a medicinal plant used in herbal remedies. The dried leaves of Anthocleista djalonensis were analyzed for their nutritional profile using standard methods. The leaves were then extracted by maceration using three different solvents: 95% analytical ethanol, hot distilled water, and local gin (78% alcohol). Various phytochemicals in the extracts were identified and quantified using standard analytical methods. Additionally, High-Performance Liquid Chromatography (HPLC) was used to compare the chemical compositions of the extracts, using a reverse-phase C18 column and UV detection at 254nm. The results of the proximate analysis revealed good nutritional value, with protein (15.90%), moisture content (9.08%), total ash (10.37%), crude fibre (4.00%), crude fat (2.40%), carbohydrate (61.53%), and an energy value of 331.33 KJ. All tested phytochemicals were found in the ethanol and local gin extracts, while the distilled water extract showed the absence of terpenoids and steroids. In the quantitative analysis, the local gin extract had the highest concentrations of alkaloids, terpenoids, flavonoids, and tannins. On the other hand, the HPLC fingerprint analysis identified seventeen (17), twelve (12), and nine (9) compounds in ethanol, local gin and water extracts respectively. Four (4) shared peaks with similar retention time were observed across all extracts, indicating the presence of common phytocompounds. In conclusion, this study shows that Anthocleista djalonensis leaves have good nutritional values, suggesting their potential as dietary phytonutrient. Local gin stands out as the best solvent among those tested for extracting beneficial compounds from Anthocleista djalonensis leaves supporting its traditional use as solvent in herbal preparation.

Combined Metabolite and Transcriptomic Profiling Unveil a Potential Gene Network Involved in the Triterpenoid Metabolism of Rose roxburghii.

Rose roxburghii, a horticulturally significant species within the Rosa genus of the Rosaceae family, is renowned for its abundance of secondary metabolites and ascorbate, earning it the title 'king of vitamin C'. Despite this recognition, the mechanisms underlying the biosynthesis and regulation of triterpenoid compounds in R. roxburghii remain largely unresolved. In this study, we conducted high-performance liquid chromatography profiling across various organs of R. roxburghii, including fruit, root, stem, and leaves, revealing distinct distributions of triterpenoid compounds among different plant parts. Notably, the fruit exhibited the highest total triterpenoid content, followed by root and stem, with leaf containing the lowest levels, with leaf containing the lowest levels. Transcriptomic analysis unveiled preferential expression of members from the cytochrome P450 (CYP) and glycosyltransferase (UGT) families, likely contributing to the higher accumulation of both ascorbate and triterpenoid compounds in the fruits of R. roxburghii compared to other tissues of R. roxburghii. Transcriptomic analysis unveiled a potential gene network implicated in the biosynthesis of both ascorbate and triterpenoid compounds in R. roxburghii. These findings not only deepen our understanding of the metabolic pathways in this species but also have implications for the design of functional foods enriched with ascorbate and triterpenoids in R. roxburghii.

Exploring the photochemical composition of indigenous Capparis Genus species in Iraq

This study presents a comparative analysis of the phytochemical compositions of the flowers and fruits of Capparis spinosa L. (Flora Iraq) sourced from Basra, southern Iraq. Soxhlet extraction and maceration methods were employed to prepare extracts for comparative phytochemical yield assessment. Total phenolic and flavonoid contents were quantified using standard controls via spectroscopic analysis. Additionally, high-performance liquid chromatography (HPLC) facilitated the identification and quantification of specific antioxidants, including cinnamic acid. Comparative analysis revealed significantly higher levels of phenols, flavonoids, and alkaloids in the flowers of C. spinosa compared to the fruits. HPLC profiling highlighted the presence of essential bioactive compounds such as kaempferol, quercetin, hexaoxane, vitamin E, and stigmasterol in both flower and fruit extracts. This study marks the first comprehensive report on HPLC profiles and quantification of prominent phytochemicals in C. spinosa (Flora Iraq) flowers and fruits from Basra, Iraq. The findings provide fundamental insights into the phytochemical compositions, serving as a valuable resource for future pharmacological research and the quality control of C. spinosa materials from this specific region.

Phytochemical analysis, Antioxidant and Antimicrobial Screening of Shoot Extracts of Viola odorata linn. from Shikari Devi Wildlife Sanctuary, Himachal Pradesh, India

The traditional healers made significant use of the Viola odorata of the Violaceae family for its many ethnopharmacological uses. The phytochemical composition and in vitro antioxidant activity of solvent extracts from Viola odorata shoots were studied, and the antibacterial potential of the optimized extract was also examined. The Soxhlet apparatus was used to extract phytochemicals from shoots in four different solvents, including n-hexane, butanol, methanol, and water. High-performance liquid chromatography (HPLC) was used to analyze the stigmasterol profile of V. odorata shoots. The extracts were found to contain alkaloids, flavonoids, terpenoids, saponins, and phenolics, all of which were found in significant amounts in the methanolic extract. The methanolic extract also showed the highest radical scavenging activity (79.23 ± 0.44 %). TLC and HPLC profiling of methanolic extract revealed a considerable amount of stigmasterol in the shoots of Viola odorata. HPLC analysis of the methanolic shoot extract of the plant revealed the presence of 0.009 µg mL-1 stigmasterol. Optimized Methanolic extract showed respectable in-vitro antimicrobial activity against Bacillus subtilis (2.6 ± 0.41 mm zone of inhibition), E. coli (3.4 ± 0.71 mm zone of inhibition), and Candida albicans (3.5 ± 0.48 mm zone of inhibition). The outcomes demonstrated that the methanolic shoot extract of Viola odorata from Shikari Devi Wildlife Sanctuary, Himachal Pradesh, India, is a valuable herb for further screening and might be prepared for in-vivo animal studies.

Chocolates Produced with Unroasted and Roasted Cocoa Beans: A Comparative Study of the Preservation of Bioactive Compounds

The aim of the present study was to evaluate the effect of roasting and cocoa mass content on the composition of chocolates. Chocolate formulations were developed (40, 50, 60 and 70% cocoa solids) using unroasted and roasted cocoa beans, and analyses were performed: physicochemical, chemical composition, antioxidant capacity, procyanidin content, total phenolic compounds, quantification of theobromine, caffeine, catechin and epicatechin by high performance liquid chromatography (HPLC) and spectroscopic profile by mid-infrared spectroscopy (MIR). The results revealed that higher values of total phenolics, epicatechin and procyanidins, were obtained in chocolates produced with unroasted cocoa beans, with a significant difference in relation to those with roasted cocoa beans. It was observed that increasing the percentage of cocoa in the formulations caused an increase in the content of bioactive compounds. The use of MIR in the differentiation of chocolate samples produced with roasted and unroasted cocoa beans obtained a positive result. This technique associated with principal component analysis (PCA) enabled the separation of chocolates according to the type of cocoa bean (roasted and unroasted) used in production, confirming its importance for a quick evaluation of the parameters.

Rapid Reversed-Phase High-Performance Liquid Chromatography Profiling of Serotonin Receptor Ligands and their Related Compounds

Rapid Reversed-Phase High-Performance Liquid Chromatography Profiling of Serotonin Receptor Ligands and their Related Compounds

The blood count as a compass to navigate in the ever-changing landscape of the carrier state of hemoglobinopathies: a single-center Italian experience.

Approximately 7% of the worldwide population exhibits variations in the globin genes. The recent migration of populations from countries where hemoglobin disorders are endemic has resulted in important epidemiological changes with the diffusion of newly discovered or poorly characterized genetic variants and new combinations and very heterogeneous clinical phenotypes. The aim of our study is to assess the parameters that are more significant in predicting a positive genetic testing outcome for hemoglobinopathies in a pediatric population of patients presenting with anemia or microcythemia, without a definite diagnosis. This study included patients evaluated in our hematological outpatient clinic for anemia and/or microcythemia despite normal ferritin levels. A screening of pathological hemoglobins using high-performance liquid chromatography (HPLC) was performed for the entire population of the study. Subsequently, patients with hemoglobin (Hb) S trait and patients with an HPLC profile compatible with beta thalassemia trait were excluded from the study. Genetic screening tests for hemoglobinopathies were performed on the remaining patients, which involved measuring the red blood cell (RBC) counts, red blood cells distribution width (RDW), reticulocyte count, and mean corpuscular volume of reticulocytes (MCVr). This study evaluated a total of 65 patients, consisting of nine patients with negative genetic analysis results and 56 patients with positive genetic analysis results. The Hb and RDW values in these two groups did not demonstrate statistical significance. On the other hand, there were statistically significant differences observed in the mean corpuscular volume (MCV), RBC count, reticulocyte count, and MCVr between the two groups. Furthermore, in the group of patients with positive genetic test results, specific genetic findings associated with different HPLC results were observed. In particular, 13 patients with positive genetic test results had normal HPLC findings. This study has demonstrated that HPLC, while serving as a valuable first-level test, has some limitations. Specifically, it has been observed that some patients may exhibit a negative HPLC result despite a positive genetic analysis. In addition to the presence of low levels of Hb and HPLC alterations, other parameters could potentially indicate the underlying mutations in the globin genes. Therefore, we propose that the complete blood cell count be utilized as a widely available parameter for conducting targeted genetic analyses to avoid the risk of overlooking rare hemoglobinopathies.

Anti-inflammatory and Antinociceptive Activity of Terminalia avicennioides Guill. & Perr. Stem Bark Extract is Distinct from the Antioxidant Effect Mediated by Its Phenolic-rich Fraction

Background: Terminalia avicennioides stem bark has been used in the management of pain and inflammatory disorders in northern Nigeria. This study evaluated the antinociceptive and anti-inflammatory properties of T. avicennioides stem bark extract and its fractions. The correlation of these effects to the presence and concentration of phenolics was also ascertained.
 Study Design: Experimental Design.
 Place and Duration of Study: Department of Pharmacology and Toxicology, National Institute for Pharmaceutical Research and Development, Idu, Abuja, Nigeria. The study was conducted from October to December 2022.
 Methods: A 70%v/v ethanol extract of T. avicennioides stem bark was prepared. Aqueous and ethyl acetate fractions (AF, EF) and sub-fractions (EF1 – EF4) were also prepared. The antioxidant capacity of the extract and fractions were determined using DPPH radical scavenging test, while xylene-induced topical ear edema and formalin test were used to assess antinociceptive and anti-inflammatory activity. The ethyl acetate sub-fractions were further assessed using the egg albumin–induced inflammation. The extract and fractions were characterized by High-Performance Liquid Chromatography (HPLC), and phenolic content was quantified as gallic acid equivalent (GAE)/mg of extract or fraction.
 Results: The ethyl acetate and aqueous fractions showed higher antioxidant capacity compared to the parent ethanol extract. T. avicennioides ethanol extract significantly inhibited pain (p<0.001) and inflammatory responses (p<0.05) and these effects were more significant compared to those produced by the fractions. Fractions AF and EF exhibited similar activity, although EF produced better inhibition of pain and topical edema. The subfraction EF2 also showed anti-inflammatory activity but this effect was insignificant (p>0.05). The HPLC profiles of the extract and fractions showed peaks corresponding to caffeic acid, chlorogenic acid, and gallic acid. The EF and AF revealed higher peak areas corresponding to gallic acid and rutin respectively. This correlated with a comparatively high gallic acid content and antioxidant effect of the ethyl acetate fraction (GAE: 1.32/mg, IC50 = 0.036 mg/ml), relative to the extract (GAE: 0.88/mg, IC50 = 0.052 mg/ml).
 Conclusion: The constituents responsible for the antinociceptive and anti-inflammatory activity of T. avicennioides extract appear distinct from antioxidative principles in phenolics-rich fractions.

Integrative HPLC profiling and transcriptome analysis revealed insights into anthocyanin accumulation and key genes at three developmental stages of black rice (Oryza sativa. L) caryopsis.

Anthocyanins are plants' secondary metabolites belonging to the flavonoid class with potential health-promoting properties. They are greatly employed in the food industry as natural alternative food colorants for dairy and ready-to-eat desserts and pH indicators. These tremendous advantages make them economically important with increasing market trends. Black rice is a rich source of anthocyanin that can be used to ensure food and nutritional security around the world. However, research on anthocyanin accumulation and gene expression during rice caryopsis development is lacking. In this study, we combined high-performance liquid chromatography (HPLC) and transcriptome analysis to profile the changes in anthocyanin content and gene expression dynamics at three developmental stages (milky, doughy, and mature). Our results showed that anthocyanin accumulation started to be visible seven days after flowering (DAF), increased rapidly from milky (11 DAF) to dough stage, then started decreasing after the peak was attained at 18 DAF. RNA-seq showed that 519 out of 14889, 477 out of 17914, and 1614 out of 18810 genes were uniquely expressed in the milky, doughy, and mature stages, respectively. We performed three pairwise comparisons: milky vs. dough, milky vs. mature, and dough vs. mature, and identified 6753, 9540, and 2531 DEGs, respectively. The DEGs' abundance was higher in milky vs. mature, with 5527 up-regulated genes and 4013 down-regulated genes, while it was smaller in dough vs. mature, with 1419 up-regulated genes and 1112 down-regulated DEGs. This result was consistent with the changes in anthocyanin profiling, and the expression of structural, regulatory, and transporter genes involved in anthocyanin biosynthesis showed their highest expression at the dough stage. Through the gene expression profile and protein interaction network, we deciphered six main contributors of the anthocyanin peak observed at dough stage, including OsANS, OsDFR, OsGSTU34, OsMYB3, OsbHLH015, and OsWD40-50. This study is the first to report the investigation of anthocyanin and gene expression at three developmental stages of black rice caryopsis. The findings of this study could aid in predicting the best harvesting time to achieve maximum anthocyanin content and the best time to collect samples for various gene expression analysis, laying the groundwork for future research into the molecular mechanisms underlying rice caryopsis coloration.

Effects of Plant Part Substitution in a Thai Traditional Recipe on α-Glucosidase Inhibition

A Thai polyherbal antipyretic remedy, TPDM6315, consists of herbal constituents that possess anti-diabetic properties. It contains 15 plants, of which the roots of 3 crude drugs, Solanum indicum (R-Si), Solanum trilobatum (R-St), and Gymnopetalum integrifolium (R-Gi), are insufficiently supplied in the herbal market, while their stems or aerial parts (S-Si, S-St, and S-Gi, respectively), are available. This study aimed to determine the anti-diabetic properties of the recipe extract and evaluate the possible substitution of those crude drugs. The chemical properties and the in vitro -glucosidase inhibition were investigated in the single herbal ingredient and the recipe extracts. The results indicated that TPDM6315 extracts inhibited -glucosidase as a mixedtype inhibitor. The high-performance liquid chromatography (HPLC) profiles between the root and stem of those herbs were different but highly similar to the recipe extracts. The substituted recipe (S-Et, containing S-Si, S-St, and S-Gi) exhibited higher potency on α-glucosidase inhibition than the original recipe (R-Et, containing R-Si, R-St, and R-Gi) (P<0.01). This study revealed substitution in TPDM6315 was possible for α-glucosidase inhibitory properties since it only partially affected the overall chemical profile while raising the α-glucosidase inhibitory activity of the recipe extracts.&nbsp

Assay of amino acids in leaves of Eucommia ulmoides under arbor forest mode and leaf-oriented cultivation mode by pre-column derivatization HPLC

This study aims to develop the pre-column derivatization high performance liquid chromatography(HPLC) method for the determination of 16 kinds of amino acids in Eucommia ulmoides leaves, and compare the content of amino acids in the leaves harvested at different time and under leaf-oriented cultivation mode(LCM) and arbor forest mode(AFM). The HPLC conditions are as below: phenyl isothiocyanate(PITC) as pre-column derivatization agent, Agilent ZORBAX C_(18 )column(4.6 mm×250 mm, 5 μm), mobile phase A of acetonitrile-water(80∶20), mobile phase B of 0.1 mol·L~(-1) sodium acetate solution-acetonitrile(94∶6), gradient elution, flow rate of 1.0 mL·min~(-1), injection volume of 5 μL, column temperature of 40 ℃, and detection wavelength of 254 nm. The HPLC profile indicated well separation of 16 kinds of amino acids and the amino acid content in E. ulmoides leaves was up to 16.26%. In addition, the amino acid content in leaves of E. ulmoides under LCM was higher than under AFM. The amino acid content varied with the harvesting time. Through orthogonal partial least squares discriminant analysis, the amino acids of E. ulmoides under LCM and AFM were compared, which can distinguish the leaves under LCM from those under AFM. Principal component analysis was applied to comprehensively score the amino acids of E. ulmoides leaves. The results showed that the score of leaves under LCM was higher than that under AFM. Nutritional evaluation results indicated that the proteins in E. ulmoides leaves belonged to high-quality vegetable proteins. The established method for the determination of amino acid content is reliable. With the amino acid content as index, the leaf quality of E. ulmoides under LCM is better than that under AFM. This study lays a theoretical basis for the promotion of LCM for E. ulmoides and the development of medicinal and edible products from E. ulmoides leaves.

High-Performance Liquid Chromatography (HPLC) Profile and Anxiolytic Activity of Hexane Extract of Datura Metel Leaves Extract in Balb/c Mice

High-Performance Liquid Chromatography (HPLC) Profile and Anxiolytic Activity of Hexane Extract of Datura Metel Leaves Extract in Balb/c Mice

Separation of Methanolic Leaf Extracts of Three Rutaceous Plants by Capillary Electrophoresis and High-Performance Liquid Chromatography Methods

Pharmacognosy Research,2023,15,2,392-398.DOI:10.5530/pres.15.2.042Published:February 2023Type:Original Article Authors:Chakravarthi Guntupalli, Narender Malothu, Ankarao Areti, Buchi N Nalluri, Praveen Sivadasu, and Narayanarao Alla Author(s) affiliations:Chakravarthi Guntupalli*, Narender Malothu, Ankarao Areti, Buchi N Nalluri, Praveen Sivadasu, Narayanarao Alla K L College of Pharmacy, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Guntur, Andhra Pradesh, INDIA. Abstract:Introduction: In the phytochemical analysis of various multi component mixtures, Capillary electrophoresis (CE) method was considered as the best alternative tool due to high efficiency resolution separations, low solvent consumption and less maintenance costs. Materials and Methods: This study uses CE and high-performance liquid chromatography (HPLC) methods to evaluate the major components of methanolic leaf extract of Rutaceous plants. And also, to assess the purity of the components in isolated fractions and most importantly for the qualitative identification of the individual components of extracts based upon the relative retention time and UV profile. Results: The separation of the compounds in HPLC was attained by using ACE-5-C18 (250 x 4.6 mm) with a flow rate of 1.5 ml/min, with the UV detection at 254 nm and CE was equipped with a UV diode-array detector and bare, fused silica capillaries (56 cm 50 μm) with micro extended light path were used for the separations. Conclusion: Our study reveals that CE technique is a simple, economical and convenient method and shown high-resolution for multi-components found in plant extracts compared with HPLC profiles. Keywords:Capillary Electrophoresis, HPLC, Relative Retention Time, Rutaceae.View:PDF (425.61 KB)

A New C2-Symmetric Atropisomeric Thiophene-Based Monomer for Inherently Chiral Electroactive Materials: Synthesis, HPLC Resolution, and Absolute Configuration Assignment

Herein, we report on the synthesis and high-performance liquid chromatography (HPLC) resolution of a new atropisomeric C2-symmetry chiral monomer based on the 3,3′-bithiophene core, which was developed to produce novel, inherently oligomeric chiral electroactive materials. The analytical enantioseparation was optimized using the cellulose-type Chiralpak IB-3 column and a mixture of n-hexane–methanol–dichloromethane 90:5:5 (v/v/v) as the mobile phase. During the scale-up of the enantioseparation analytical conditions to a semipreparative level, remarkable deformations in the HPLC profile, such as peak splitting and plateau zones between enantiomeric peaks, were observed. We demonstrate the effects of sample diluent as they relate to distorted peak profiles, as well as provide experimental solutions to prevent the disturbing phenomenon. The optimized chromatographic conditions were exploited to collect milligram amounts of the enantiopure sample, which was submitted to chiroptical and stereochemical characterization studies.

Characterization of Hypolipidemic Phenol Analogues from Fermented Tea by Eurotium cristatum

Fuzhuan brick tea (FBT), a type of black tea, is a traditional beverage in China, especially popular among frontier ethnic groups. FBT is well-known for its health benefits, such as hypoglycemic, anti-hypertensive, anti-inflammatory, diuretic, and detoxification effects. Nevertheless, the underlying mechanisms on the molecular level are still elusive and the key compounds responsible for the health benefits are unidentified. Previous studies have mainly focused on functional studies of the water extract. However, FBT is typically cooked with butter or milk. Therefore, we hypothesized that some lipophilic components in FBT, which can be absorbed through the co-consumption of butter or milk, may play an important role in the health benefits. The present study aimed to investigate whether the liposoluble extract of FBT alleviates symptoms related to metabolic diseases and to identify the active compounds involved. By comparing the high-performance liquid chromatography (HPLC) profiles of water, milk and hexane extract, some low polarity peaks were observed in the milk and hexane extracts. Furthermore, the hexane extract treatment alleviated body weight gain, serum total cholesterol and triglyceride levels, and inhibited the accumulation of hepatic fat granules in a high-fat diet (HFD)-induced C57BL/6N mouse model. In order to identify the key functional lipophilic compounds in FBT, the hexane extract of FBT was subjected to chemical characterization. Four phenol analogs were characterized, namely, isodihydroauroglaucin (1), dihydroauroglaucin (2), tetrahydroauroglaucin (3), and flavoglaucin (4). Compounds 1 and 4 reduced the levels of total cholesterol and triglyceride in vivo. Both compounds also inhibited the high-fat diet-induced body weight gain and accumulation of fat granules in the liver of C57BL/6N mice. Isodihydroauroglaucin and flavoglaucin have therefore been identified as bioactive ingredients that contribute to the health benefits of FBT.

Chemical synthesis of per-selenocysteine human epidermal growth factor.

Human seleno-epidermal growth factor (seleno-EGF), a 53-residue peptide where all six cysteine residues of the parent human EGF sequence were replaced by selenocysteines, was synthesized and the oxidative folding of a polypeptide containing three diselenide bonds was compared to that of the parent cysteine peptide. The crude high performance liquid chromatography (HPLC) profiles clearly showed that both the native EGF and its selenocysteine-analogue fold smoothly, yielding a single sharp peak, proving that even in the case of three disulfide-bonded polypeptides the disulfide-to-diselenide bond substitution is highly isomorphous, as confirmed by conformational circular dichroism measurements and particularly by the biological assays.

Process Development of a Triphasic Continuous Flow Suzuki–Miyaura Coupling Reaction in a Plug Flow Reactor

We have successfully adapted a Suzuki–Miyaura coupling reaction to a continuous flow process. The reaction was a triphasic mixture involved with two liquid phases that are only partially miscible in addition to the presence of an insoluble catalyst as a solid phase. The reaction required very rapid reaction heat up and mixing, which were difficult to achieve under batch conditions. A plug flow reactor (PFR) equipped with a static mixer was implemented in this continuous flow process, and the heterogenous reaction mixture was well handled, which is attributed to the high velocity flow rates and fast reaction kinetics. The reaction was successfully carried out on a 1.6 kg scale to give 80% isolated yield of the product with superior reaction high-performance liquid chromatography profile to the batch process.

Hydrobiological and Bio-Optical Characterization of a Red Tide Occurredin Meda Creek, Porbandar, India

Red tides are becoming more common in aquatic ecosystems, particularly the coastal habitats which are highly influenced by climatic and anthropogenic activities. We provide the first report of a red tide event in Meda creek, west coast of India. Light and scanning electron microscopy were used to identify the bloom forming organism, while physicochemical, biological and biooptical parameters were determined to characterize the aquatic body of the Meda Creek. The dominant bloom forming organisms were observed as unarmored, spherical, dorsoventrally compressed flagellate with truncated apex, notched and rounded hypocone, displaced premedian cingulum and extending sulcus. The length wise size of the cell varied from 20 to 30.83μM, whereas, the width varied from 14 to 27.5μM. The organisms was identified as Gymnodinium sp. High Performance Liquid Chromatography (HPLC) and spectral profile of the bloom indicatedeleven major peaks corresponding to that of 19-but-fucoxanthin (52.75%), astaxanthin (9.62%), fucoxanthin (8.81%), Mgdv (6.45%), prasinoxanthin (3.35%), chlorophyll C2 (3.22%), neoxanthin (3.12%), antheraxanthin (3.14%), diadinoxanthin (2.63%) and diatoxanthin (1.38%). Chlorophyll a concentration in the bloom sample was 38.8μg/L. Water temperature, salinity, NH3-N, NO2-N, NO3-N, PO4-Pwere higher during the bloom period than the non-blooming ones, while metals including Fe, Zn, Cr, Mn and Co were lower. No death of aquatic biota was observed. We propose that eutrophication along with the warm and saline conditions provided enabling conditions for occurrence the bloom. Also, most of the pigments expressed have antioxidant role and might be purposeful for the survival of the organism in the extreme condition of temperature and salinity recorded. Proper management and monitoring measures might help mitigate further occurrences of this bloom in the light changing climate and increasing anthropogenic impacts.

Dehydration and Rehydration Kinetics Modeling in the Phytochemical, Aroma, and Antioxidant Capacity of Tree Tomato Fruit Dried with Microwaves and Freeze Driers: A Comparative Study

In the present study, we investigated and compared the effect of microwaves and freeze-drying methods on the dehydration and rehydration kinetics in the phenolic, anthocyanin, aroma profiles, and antioxidant properties of tree tomato fruit (Solanum betaceum). The tree tomatoes were dried using microwaves at 350 W, 500 W, and 650 W, and then freeze-dried. The obtained drying curves were processed to find the most suitable mathematical modeling among the different moisture ratio expressions. Total phenolics, total anthocyanins, total flavonoids total carotenoids, vitamin C, Ferric Reducing Antioxidant Power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were tested. Using High performance Liquid Chromatography (HPLC), phenolic and anthocyanin compound profiles were identified. The aroma profile was analyzed using gas chromatography-MS. The Midilli model, among others, precisely describes the dehydration methodology of all used drying methods with the coefficient of determination R2 = 0.99. On the other hand, the Weibull model precisely describes the rehydration process of the used drying methods (R2 = 0.99). Physical changes (color, shrinkage) were also studied. The freeze-dried tree tomatoes had a high number of phenolic compounds with 3.94 ± 0.26 mg GAE/g and total carotenoid compounds with 0.48 ± 0.04 µg/g. Epicathechin was the most abundant compound among the tested phenolics, followed by Cathechin. The Pelargonidin-3-glucoside was the most abundant anthocyanin whereas in freeze-dried tree tomatoes, 1.22 ± 0.01 mg/g. Fifty-four aroma compounds were detected and quantified. Among others, Eucalyptol was one of the most abundant aroma compounds analyzed in dried tree tomato fruit. Freeze-dried tree tomatoes retained most of the antioxidant and flavor compounds analyzed.

Characterization of regioisomeric diterpenoid tails in bacteriochlorophylls produced by geranylgeranyl reductase from Halorhodospira halochloris and Blastochloris viridis.

Geranylgeranyl reductase (GGR) encoded by the bchP gene catalyzes the reductions of three unsaturated C = C double bonds (C6 = C7, C10 = C11, and C14 = C15) in a geranylgeranyl (GG) group of the esterifying moiety in 17-propionate residue of bacteriochlorophyll (BChl) molecules. It was recently reported that GGR in Halorhodospira halochloris potentially catalyzes two hydrogenations, yielding BChl with a tetrahydrogeranylgeranyl (THGG) tail. Furthermore, its engineered GGR, in which N-terminal insertion peptides characteristic for H. halochloris were deleted, performed single hydrogenation, producing BChl with a dihydrogeranylgeranyl (DHGG) tail. In some of these enzymatic reactions, it remained unclear in which order the C = C double bond in a GG group was first reduced. In this study, we demonstrated that the (variant) GGR from H. halochloris catalyzed an initial reduction of the C6 = C7 double bond to yield a 6,7-DHGG tail. The intact GGR of H. halochloris catalyzed the further hydrogenation of the C14 = C15 double bonds to give a 6,7,14,15-THGG group, whereas deleting the characteristic peptide region from the GGR suppressed the C14 = C15 reduction. We also verified that in a model bacterium, Blastochloris viridis producing standard BChl-b, the reduction of a GG to phytyl group occurred via 10,11-DHGG and 6,7,10,11-THGG. The high-performance liquid chromatographic elution profiles of BChls-a/b employed in this study are essential for identifying the regioisomeric diterpenoid tails in the BChls of phototrophic bacteria distributed in nature and elucidating GGR enzymatic reactions.