Dimethylamino Cinnamaldehyde Research Articles

Spectrophotometric Determination of Ampicillin Using Chromogenic Reagents (MBTH and PDAC) and their Application in Pharmaceutical Formulations

The present work highlights the spectrophotometric method development and validation for the assay of ampicillin, a broad-spectrum β-lactam antibiotic. Two methods have been proposed by employing popular chromogenic reagents viz 3-methyl 2-benzothiazolinone hydrazone (MBTH) and para dimethyl amino cinnamaldehyde (PDAC). Method A involves the coupling of ampicillin with MBTH in the presence of ferric chloride through the oxidative mechanism, resulting in the formation of green coloured solution with a maximum absorption peak at 620 nm. In method B, the condensation reaction of ampicillin with an acidic solution of PDAC gave a coloured reddish-brown complex, showing a maximum absorption peak at 514nm. Linear calibration curve for MBTH and PDAC has been obtained while obeying Beer’s law in the concentration range of 0.5 -1 and 5-15 μg/ml having a good correlation coefficient of 0.9985 and 0.9974 respectively. The sensitivity of the submitted methods was found to be more than the reported methods. Both methods were successfully applied to a pharmaceutical formulation for quantifying the ampicillin effectively. Therefore, the developed spectrophotometric methods can serve as a good analytical assay procedure for ampicillin to undergo quality control in pharmaceutical setups.

Exploring Enhanced Electrocatalytic Hydrogen Evolution by Metal‐Free Highly Conjugated Azomethine‐Functionalized Graphitic Carbon Nitride

The water‐splitting reaction via electrocatalyst is a potential method for hydrogen evolution reaction (HER), and metal‐free electrocatalytic material with excellent performance are in great demand for future applications. In this context, a novel, facile, and efficient route for the synthesis of highly conjugated azomethine‐functionalized graphitic carbon nitride (GCN) is proposed. The GCN functionalized with azomethine moiety by using various proportions of GCN–x% dimethyl amino cinnamaldehyde (DMAC) (x = 0.1%, 0.5%, 1.0%, 5.0%, and 10.0%) of p‐DMAC leads to introduction of azomethine moiety onto the GCN matrix that does not affect the original framework of GCN network, but it efficiently enlarges its π‐delocalized system, increases its surface area, and enhances the electrocatalytic properties. All the structural and morphological properties of synthesized materials are analyzed by X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, Brunauer–Emmett–Teller, High resolution transmission electron microscopy, and field emission scanning electron microscopy, with Energy dispersive spectroscopy analysis. Furthermore, the GCN–5.0% DMAC exhibits superb HER performance with onset potential near to 0 V, and a low overpotential of 18.7 mV at 5 mA cm−2, and extremely ultrasmall Tafel slope (46.8 mV dec−1) in an 0.5 m H2SO4. In this study, the door is laid for interfacial engineering to be used as an efficient method for economically developing electrocatalysts.

Insight into the corrosion inhibition mechanism and adsorption behavior of aldehyde derivatives for mild steel in 1.0 M HCl and 0.5 M H2SO4

The inhibition effect of dimethylaminocinnamaldehyde (DACA) on the corrosion of mild steel in 1.0 M HCl and 0.5 M H2SO4 solutions was studied by electrochemical techniques and quantum chemical calculation, polarization studies revealed that DACA behaves as a mixed-type inhibitor. Electrochemical impedance spectroscopy (EIS) results indicated that DACA is a good inhibitor in 1.0 M HCl and 0.5 M H2SO4 of the steel surface and inhibition efficiency follows the order: H2SO4 >HCl. The adsorption of the studied inhibitor on a mild steel surface follows Langmuir’s adsorption isotherm and involved a chemisorption mode. SEM/EDX observations of the electrode surface confirm the existence of a film on the metal surface. Furthermore, DFT calculations revealed that DACA is in good correlation with the experimental results and Molecular dynamics simulations showed a strong interaction between this molecule and the mild steel surface.

Trend of Antioxidant Activity and Total Phenolic Content in Wild Edible Plants as Part of the Environmental Quality Assessment of Some Areas in the Central Italy

Polyphenols are secondary metabolites of interest due to their potential application in various fields. This study is supposed to analyse the content of total polyphenols, total tannins, condensed tannins and antioxidant activity of ten wild plant species of nutritive interest to better understand their potential applications. Furthermore, the effect of heavy metals on the production of the investigated secondary metabolites was analysed. The different phenolic compounds were determined in methanol extracts obtained from edible plants collected during three sampling periods (June, September and November–December) in four areas of the Central Italy. Analyses were carried out by applying standard methodologies. In particular, total polyphenols were determined by the Folin–Ciocalteu method, total tannins by the polyvinylpolypyrrolidone (PVPP) reagent and condensed tannins by the 4-(dimethylamino)cinnamaldehyde (DMCA). Antioxidant activity was determined by assessing the scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). The results showed a satisfactory content of phenolic compounds and antioxidant activity for all species analysed. Furthermore, the existence of a negative correlation between the presence of heavy metals and phenolic compounds was found. Results proved the potential use of these plants for balanced feeding of ruminants.

Cinnamaldehyde‐based Natural Product as Viscosity‐Sensitive Sensor toward Liquid Safety Inspection

AbstractLiquids spoiled is considered gradually as a serious public problem, and heavily medical burden has been caused by this. We suspected that the viscosity level in the deterioration process is higher than those in the normal ones. For this reason, we have presented promising sustainable natural product, 4‐(dimethylamino)cinnamaldehyde (DLCA), for monitoring micro‐environmental viscosity alterations to achieve liquid safety inspection in a high sensitivity, rapid detection, and cheap equipment dependence pathway. This natural sensor with large stokes shift of 106.8 nm and maximum emission wavelength of 486.0 nm with high signal‐to‐noise ratio intensity. DLCA is consisted of a typical dimethylamine donor and aromatic aldehyde acceptor, connected with a rotatable single and double conjugated bond. The fluorescence intensity of this natural sensor increased 70 times with the enhancement of viscosity. The interference of other microenvironments such as pH and polarity, various potential analytes can be reduced. With the assistance of the fluorescence imaging technique, DLCA could sensitively and selectively non‐invasively identify thickening efficiency of various thickeners. Furthermore, DLCA may provide an attractive way to evaluate liquid deterioration extent with viscosity as a robust marker. We expected that this unique strategy will accelerate the efficient utilization of clean and reproducible resources.

Sampling Plan for a Study of Cranberry Dietary Supplements (DS) for the Dietary Supplement Ingredient Database (DSID)

ObjectivesThe intake of cranberry juice or supplements has been found in several, but not all, clinical studies to reduce the recurrence of urinary tract infections (UTIs). Several studies indicate that cranberry proanthocyanidins (PACs) may have a role in UTI prevention due to their ability to inhibit bacterial adhesion. For cranberry DS products on the US market, the relationship between PAC content and the cranberry source (e.g., powder, juice, extract) used in formulations is largely unknown. Therefore, a sampling plan was developed to identify and purchase DS for PAC testing as part of the Dietary Supplement Ingredient Database project. This will include popular cranberry DS, those used in clinical trials, and products with a variety of label claims and source ingredients. MethodsDS usage data from the National Health and Nutrition Examination Survey and retail sales data were used to identify the most popular cranberry DS in the natural health (NH), mass market (MM), and direct distribution sales channels. Other sources of information were the Dietary Supplement Label Database and web-based DS sellers. Three DS label categories were identified: those with a trademarked cranberry ingredient, those without a trademarked cranberry ingredient, and those with a numeric PAC claim. Some products may fall into two categories. Most products chosen for the study had cranberry as the primary ingredient by weight. Popular products with D-mannose and vitamin C were also included. ResultsIn the first phase of this study, we purchased 41 DSs (18 MM, 11 NH, and 12 direct). Our sample included caplets, capsules, soft gels, tablets, and liquid DSs. Cranberry source materials for the DSs included extracts, concentrates, powder, juice, and whole fruit. Fifteen (15) supplements had trademarked cranberry ingredients and 9 had a specific voluntary claim for PAC content. ConclusionsIn 2020, cranberries were the 6th ranked herbal ingredient sold in the US, according to the Nutrition Business Journal. The range of PAC content in the diverse cranberry DSs on the market is currently not known, since there is no requirement for this information on labels. This study will answer questions about the PAC content in a variety of DSs and whether multiple laboratories testing using the dimethylaminocinnamaldehyde (DMAC) method will yield similar results. Funding SourcesNIH ODS and the USDA.

Inter-Laboratory Validation of 4-(Dimethylamino) Cinnamaldehyde (DMAC) Assay Using Cranberry Proanthocyanidin Standard for Quantification of Soluble Proanthocyanidins in Cranberry Foods and Dietary Supplements, First Action Official MethodSM: 2019.06.

Proanthocyanidins (PAC) are oligomers and polymers of flavan-3-ols with putative health benefits. PAC are prevalent in a wide variety of natural products and dietary supplements. An inter-laboratory study was conducted to validate the 4-(dimethylamino)cinnamaldehyde (DMAC) colorimetric assay using a 96-well plate spectrophotometer for the accurate quantification of PAC in cranberry products and to evaluate the comparison of the procyanidin A2 (ProA2) dimer and cranberry PAC (c-PAC) reference standards. Four test materials analyzed in this study included cranberry fiber powder, cranberry extract powder, concentrated cranberry juice, and a solution of cranberry PAC (30%, w/v). The samples were homogenized, extracted, sonicated, centrifuged, and analyzed using a 96-well plate spectrophotometer. Linearity for both the ProA2 and c-PAC standards was determined from 4.053 to 50.666 µg/mL and from 13.520 to 135.95 µg/mL, respectively. The relative standard deviation of repeatability (RSDr) values for the four materials analyzed, using both ProA2 and c-PAC standards, met the Standard Method Performance Requirements (SMPR®). Inter-laboratory precision using Horwitz ratio (HorRat) values for the four materials analyzed, using both ProA2 and c-PAC standards, satisfies the acceptance range in Appendix K of the Official Methods of Analysis (2003): Guidelines for Dietary Supplements and Botanicals. The limit of quantification (LOQ) was estimated to be 3.16 µg/mL. The results produced from this study demonstrate the utility of the c-PAC standard over the ProA2 standard and the advantages of using a 96-well plate spectrophotometer for the accurate quantification of PAC. The use of a 96-well plate reader and c-PAC reference standard in the DMAC method improves accuracy and percision for quantification of soluble proanthocyanidins in cranberry foods and dietary supplements.

Nanoparticle-assisted pyrrolidonyl arylamidase assay for a culture-free Group A Streptococcus pyogenes detection with image analysis

Existing techniques for the detection of Group A Streptococcus pyogenes (GAS) have drawbacks in rapidness, accuracy or in high-cost. Considering the clinical importance of GAS, we have developed a culture-free detection method based on pyrrolidonyl arylamidase (PYR) activity with the aid of magnetic gold nanoparticles (AuNPs). GAS is the reason for pharyngitis and sampling starts from the throat with cotton swabs. After swab sampling, the target was collected with antibody modified magnetic AuNPs and transferred into 500 μL of PYR-broth without any antigen extraction or pure colony isolation. Then, the assay was finished by adding 25 μL of 4-(dimethylamino)-cinnamaldehyde (DMACA) reagent after 4-h incubation. A red color formation was evaluated as the presence of GAS comparing to blank, however, image analysis was employed for the interpretation of color changes clearly. For this purpose, a formula related to image data was proposed and analytical validation parameters were defined. Thus, the correlation was found to be linear with the R2 of 0.9685 between the log of bacteria concentration and the image data with the limit of detection of 3.3 × 102 CFU/mL of GAS. In addition, the assay worked efficiently in the abundance interference of Enterococcus faecalis. The results represent a new feature to nanoparticles eliminating the selective growth media for a bacteria and this study provided a detection with intact cells of bacteria without any antigen or DNA/RNA extraction. The proposed work has been the most similar to the gold standard but a faster method in this field.

Vacuum infiltration enhances the Agrobacterium-mediated transient transformation for gene functional analysis in persimmon (Diospyros kaki Thunb.)

An Agrobacterium-mediated transient transformation system was established for gene functional analysis in persimmon (Diospyros kaki Thunb.) utilizing sonication followed by vacuum infiltration of seedlings in vitro. The optimal vacuum conditions for agroinfiltration of persimmon were evaluated by monitoring expression of GUS reporter gene. The technique was further applied to evaluate five different genotypes. Among the genotypes examined in vitro, ‘Xiaoguo-tianshi’ (Chinese PCNA type) produced the highest expression levels of both GUS and GFP, and was the most ideal genotype. Furthermore, the developed system was successfully utilized for DkLAR (leucoanthocyanidin reductase) gene transient silencing. DMACA (4- dimethylaminocinnamaldehyde) staining and the Folin-Ciocalteau assay revealed that the proanthocyanidins (PAs) levels was markedly decrease in ‘Xiaoguo-tianshi’ and ‘Mopanshi’ (Chinese PCA type) leaves. These results confirmed that DkLAR plays an important role in the accumulation of PAs in persimmon. In conclusion, based on the Agrobacterium-mediated vacuum infiltration, we developed a reliable and highly efficient transient transformation system that can be used for gene functional analysis through the seedlings in vitro.

A rapid and sensitive fluorometric method for determination of aldehyde oxidase activity

Previous research has characterized the important role of aldehyde oxidases (AOX) in biotransformation of N-heterocyclic therapeutic drugs and environmental contaminants in mammals. Research pertaining to AOX activity in non-mammalian vertebrates, however, is scarce, despite its biological role as a potentially important metabolic pathway for xenobiotics. One of the limiting factors of research on AOX is that available photometric methods are relatively insensitive, limited in throughput, and prone to cross-reactivity from other enzymes. Therefore, this study aimed to develop a novel and improved fluorometric AOX assay. This assay is based on the conversion of the exogenous aldehyde substrate 4-(dimethyl)amino cinnamaldehyde to its corresponding fluorescent acid by AOX, and was evaluated using partially purified hepatic cytosol from rat, human, and rainbow trout. Purification of native cytosol by heat treatment and ammonium sulfate precipitation resulted in increased specific activity of AOX. Michaelis-Menten kinetic parameters (Kmand Vmax) were comparable to values previously generated by photometric methods. Furthermore, effects of the inhibitor hydralazine on AOX activity revealed half maximal inhibitory concentrations comparable to those generated using conventional methods. Product identity was confirmed by liquid chromatography and mass spectrometry. In summary, this study successfully developed a rapid and sensitive assay for determination of AOX activity in across different vertebrate species that is 4- to 10-fold more sensitive compared to conventional absorbance-based methods. It can be applied in environmental, toxicological, and pharmacological studies relating to identification of AOX substrates, as well as the induction of AOX expression through drugs and environmental contaminants.

Characteristics of Color Development in Seeds of Brown- and Yellow-Seeded Heading Chinese Cabbage and Molecular Analysis of Brsc, the Candidate Gene Controlling Seed Coat Color

The proanthocyanidin (PA) is the main flavonoids which affect the seed coat color in Brassica species. In this paper, characteristics of color development and accumulation of flavonoids were analyzed in the seeds of brown-seeded (B147) and yellow-seeded (B80) heading Chinese cabbage (Brassica rapa L. ssp. Pekinensis). It is found that the content of phenolic compounds in B147 were significantly more than that of B80 by using dimethylaminocinnamaldehyde (DMACA) staining and toluidine blue O (TBO) staining. In previous studies, the locus associated with seed coat color has been mapped. The results of whole genome re-sequencing showed that there are large fragment deletions variation in the mapping region between the brown-seeded parent ‘92S105’ and the yellow-seeded parent ‘91-125.’ Based on the B. rapa genome annotation information, the TRANSPARENT TESTA GLABRA 1 (TTG1), is likely to be the candidate gene controlling seed coat color. A 94-base deletion was found in the 96th base downstream of the initiation codon in the TTG1 of yellow seed, thus, the termination codon TGA was occurred in the 297th base which makes the full length of TTG1 of yellow seed is 300 bp. Based on the differential sequences of TTG1 of brown and yellow seed, a functional marker, Brsc-yettg1, was developed to detect the variation of TTG1. Quantitative real-time PCR analysis of BrTTG1 in different tissues showed that expression levels of BrTTG1 was not tissue-specific. During the whole seed development period, the expression of BrTTG1 in B147 was higher than that of B80. The expression levels of four structural genes, BrDFR, BrANS, BrANR1, and BrANR2 in B147 were also higher than those in B80. The co-segregation molecular markers obtained in this report and TTG1 related information provide a basis for further understanding of the molecular mechanism of seed coat color in heading Chinese cabbage.

Acclimation Changes of Flavonoids in Needles of Conifers during Heat and Drought Stress 2015

The long-term harsh climate conditions in 2015 distorted already from June up to November in all study trees of Tsuga and Taxus the intracellular organization of the needles. Intimately involved in these repressive processes were the flavanols, a small subgroup of the flavonoids. They were not only deposited in vacuoles of conifer needles but also in the nuclei and chromosomes. Among the many flavonoids the small group of catechin derivatives and polymers named flavanols can exclusively be stained blue with DMACA (dimethylaminocinnamaldehyde). From mid-July onward, the vacuolar flavanols of the epidermal cell layers were gradually diminished as evidenced by decreasing blue staining of nuclei and vacuoles. Subsequently, in August also the large spongy mesophyll cells showed the flavanols decreasing progressively. Apparently, the antioxidant flavanols operate as oxygen radical scavengers. (ROS) were used up during the harsh environmental stress conditions. Both, Tsuga and Taxus reacted in this way. However, it is quite surprising that in all study trees the palisade cells did not contain such vacuolar flavanols. Only these cells were in June the first to show a loss of chlorophyll from chloroplasts as well as an efflux of flavanols from the nuclei. Conversely, from September onward another group of phenols, the yellow-staining flavanols were newly formed in the palisade cells and later on also in the mesophyll cells. Obviously, they were assembled finally to stabilize finally the fragile cell sites. Summing up, the present study shows by cytological studies that the climatic conditions in 2015 produced the worst disturbance of subcellular structures observed since 2000 when our studies on nuclear phenols in needles of conifers were initiated.

In vitro shoot multiplication and ex vitro rooting of Eustoma grandiflorum by shoot tips using 2,4-D and BAP

An Agrobacterium-mediated transient transformation system was established for gene functional analysis in persimmon (Diospyros kaki Thunb.) utilizing sonication followed by vacuum infiltration of seedlings in vitro. The optimal vacuum conditions for agroinfiltration of persimmon were evaluated by monitoring expression of GUS reporter gene. The technique was further applied to evaluate five different genotypes. Among the genotypes examined in vitro, ‘Xiaoguo-tianshi’ (Chinese PCNA type) produced the highest expression levels of both GUS and GFP, and was the most ideal genotype. Furthermore, the developed system was successfully utilized for DkLAR (leucoanthocyanidin reductase) gene transient silencing. DMACA (4- dimethylaminocinnamaldehyde) staining and the Folin-Ciocalteau assay revealed that the proanthocyanidins (PAs) levels was markedly decrease in ‘Xiaoguo-tianshi’ and ‘Mopanshi’ (Chinese PCA type) leaves. These results confirmed that DkLAR plays an important role in the accumulation of PAs in persimmon. In conclusion, based on the Agrobacterium-mediated vacuum infiltration, we developed a reliable and highly efficient transient transformation system that can be used for gene functional analysis through the seedlings in vitro.

Critical reevaluation of the 4-(dimethylamino)cinnamaldehyde assay: Cranberry proanthocyanidin standard is superior to procyanidin A2 dimer for accurate quantification of proanthocyanidins in cranberry products

The 4-(dimethylamino)cinnamaldehyde (DMAC) assay is currently used to quantify proanthocyanidin (PAC) content in cranberry products. In a multi-operator/multi-day study design, a cranberry proanthocyanidin (c-PAC) standard was compared to procyanidin A2 (ProA2) dimer for accurate quantification of PAC in commercial cranberry juices, lab generated cranberry blends and cranberry powders. The c-PAC standard reflects the structural heterogeneity of cranberry PAC degree of polymerization, hydroxylation pattern and ratios of ‘A-type’ to ‘B-type’ interflavanyl bonds. Use of the c-PAC standard to quantify PAC content in cranberry samples resulted in values that were 3.6 times higher than those determined by ProA2. Overall, there was no effect (P > 0.05) of operator or day on estimation of PAC concentration. The adoption of c-PAC standard should be considered as an improvement over the use of ProA2 for accurate quantification of cranberry PAC. Improved standardization of bioactive PAC components in functional cranberry foods will aid in establishment of dosage guidelines.

Flavanols in the nuclei of the tea bush (Camellia sinensis) - broadening the perspectives to human health

800x600 Flavanols as a small subclass of the flavonoids stain selectively blue with the special reagent p -dimethylaminocinnamaldehyde (DMACA). Because of the prominent blue colour it is easy to recognize the flavanols histochemically in the vacuoles of expanding and maturing cells. However, the cells of the tea shrub ( Camellia sinensis L.) show those blue coloured flavanols also in the nuclei. Silenced interphase nuclei of mature parenchyma cells indicate a pronounced diffuse distribution of blue stained flavanols. By contrast, in activated nuclei the flavanols reflect a variable, mosaic-like blue patterning enclosed by white interchromatin spaces. Subnuclear expression of euchromatin displays relative tiny blue dots of flavanols as compared with the larger-sized blobs of heterochromatin. From metaphase to telophase, the chromosomes stain a fairly dark blue with a more or less diffuse appearance. Those nuclei running through mitotic interphases from G 1 to G 2 have well-defined flavanol-free nucleoli. The flavanol pattern of meristematic chromosomes found in the tea plant is basically also valid for herbaceous plants, such as Hyacinthus romanus , Tulipa gesneriana and Allium cepa, which genuinely do not contain nuclear flavanols. This was verified by incubation of their rootlets in solutions of green tea and epigallocatechin gallate (EGCG). Also human nuclei demonstrate an easy import of added flavanols and the resulting blue stained chromatin reflects in much the same way the structural modifications as already described for the plant nuclei. Possible roles of flavanols in organizing basic mechanisms of chromatin remodelling are discussed. Hereby, also the overall problem of easy oxidizable flavanols should be integrated. Flavanols have the potential to associate to the histone proteins of chromatin. Even small fragments of histones can aggregate to catechin as shown on the basis of kinetic measurements for the H4-core peptide HAKRKT and its acetylated product HAK(ac)RK(ac)T according to the epigenetic histone code. Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:Normale Tabelle; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Times New Roman,serif;}

Evaluation of in vitro anti‐hyperglycemic effect of Cinnamon cassia derived phenolic phytochemicals

Cinnamon cassia (Cinnamon) proanthocyanidins (PACs) are shown to have anti‐hyperglycemia potential. The present study investigates the carbohydrate hydrolysis enzyme inhibition of cinnamon PACs. Five grams of cinnamon bark powder were extracted in 100 mL acetone solution (CAE) (acetone: water: hydrochloric acid, 70:29.9:0.01) for 2 hours at room temperature and in 100 mL deionized water for 30 min at 90 □ (CWE). PACs were purified from CAE using LH‐20 (CAE‐PAC) to be further evaluated. PAC contents were evaluated by 4‐ Dimethylaminocinnamaldehyde (DMAC) assay and yielded 795, 177 and 123 mg/g, for CAE‐PAC, CAE and CWE respectively. The total phenolic contents of CAE and CWE were determined to be 152 and 134 mg/g respectively. All extracts were adjusted to the same PAC content (180, 90, 45 and 20 μg) and the inhibitory activity against rat α‐glucosidase was determined. The CAE‐PAC fraction had very low rat α‐glucosidase inhibitory activity, CAE had the highest (IC50 3.13 mg/mL DW) followed by CWE (IC50 5.21 mg/mL DW). The specific maltase and sucrase inhibitory activities were determined and CAE (IC50 2.47 and 0.63 mg/mL DW) had higher inhibition than CWE (IC50 5.56 and 2.79 mg/mL DW). Results suggest that the observed bioactivity is not PAC dependent and that CAE has higher anti‐hyperglycemic potential than CWE via inhibition of carbohydrate hydrolysis enzymes.This research was supported by US Army Natick Soldier Research Engineering Center

Impact of harvest timing on the polyphenol content of black chokeberry (Aronia melanocarpa, cv ‘Viking’) juice.

Chokeberry (Aronia melanocarpa) is rich in polyphenols with potential nutraceutical value. The objective of this study was to determine the peak polyphenol content of Viking chokeberries over the span of possible harvest dates within a single growing season. Berries were grown in Storrs, CT and randomized into 10 plants/block. At the onset of ripeness, 5 blocks were harvested weekly until the last harvestable date, for 7 weeks. The polyphenol content of pressed juice was measured using UPLC‐MS, and by the 4‐(dimethylamino) cinnamaldehyde (DMAC) and Folin‐Ciocalteu assays. Changes in sugar content were analyzed using a refractometer and quantified in degrees brix. Sugar content rose gradually from 10.5 ± 0 to 14.3 ± 0.3 degree brix between weeks 1 and 7. Anthocyanins increased from 366 ± 3 to 1200 ± 39 μg/mL between weeks 1 and 5 and then declined by 32% by week 7. Proanthocyanidins increased from 214 to 352 μg catechin equivalents/mL between weeks 1 and 7. Hydroxycinnamic acid content declined from 1,250 ± 0 to 835 ± 25 μg/mL between weeks 1 and 7. Total phenol content rose from 4.03 to 5.03 mg gallic acid equivalents/mL between weeks 1 and 7. Thus, the polyphenol content of Viking berry juice was greatest at 7 weeks of ripeness, about 20% higher than week 1. However, maximum juice anthocyanins occurred at 5 weeks of ripeness. Funding provided by the University of Connecticut Diet and Health Initiative.

화학시약들을 이용한 지류에서 혈흔지문 증강에 관한 연구

혈흔지문은 매우 중요한 증거물이다. 본 실험은 지류에 유류된 혈흔지문에 대해 화학시약인 닌히드린, leucocrystal violet (LCV), fuchsin acid, 요오드, dimethylaminocinnam aldehyde (DMAC) 시약들의 증강효과를 확인한 것이다. 혈흔지문은 종이에 순차적으로 유류시킨 후 실온에서 건조해 사용하였다. 혈흔지문 융선이 비교적 선명할 경우에는 닌히드린과 LCV 시약이 가장 효과적이었지만, 눈에 보이지 않는 융선에 대한 증강효과는 크지 않았다. Fuchsin acid 시약을 사용하면 종이 표면이 염색되므로 혈흔지문의 contrast는 오히려 감소했다. 요오드 시약으로 혈흔지문 융선이 증강되긴 했지만, 반응 후 발색이 약하고 증강효과도 크지 않았다. DMAC 시약은 선명한 혈흔지문에 대한 증강효과가 좋지 않았지만, 희미한 융선에 대한 증강에는 매우 효과적이었다. 메탄올로 세척함으로서 DMAC로 증강된 혈흔지문의 contrast를 높일 수 있었다. Bloody fingerprint is a very important evidence. In this study, we confirmed the enhancement effects of ninhydrin, leucocrystal violet (LCV), fuchsin acid, iodine and dimethylaminocinnamaldehyde (DMAC) on bloody fingerprints which were deposited on paper. Bloody fingerprint were deposited on paper sequentially and used after drying at room temperature. If a ridge of bloody fingerprint was clear, ninhydrin and LCV was the most effective but was not good for invisible ridge. Fuchsin acid reagent dyed paper surface so that the contrast of enhanced bloody fingerprint was decreased. Although bloody fingerprint was enhanced with iodine reagent, but the developed color was very weak after reaction. We thought that the enhancement effect of iodine to bloody fingerprint was negligible. Also, the enhancement effect of DMAC reagent to relatively clear bloody fingerprint was not good. However, it was very effective to faint or invisible ridge. By washing with methanol, contrast of enhanced bloody fingerprint was increased.

Comparison of Isolated Cranberry (Vaccinium macrocarpon Ait.) Proanthocyanidins to Catechin and Procyanidins A2 and B2 for Use as Standards in the 4-(Dimethylamino)cinnamaldehyde Assay

The 4-(dimethylamino)cinnamaldehyde (DMAC) assay is currently used to quantify proanthocyanidin (PAC) content in cranberry products. However, this method suffers from issues of accuracy and precision in the analysis and comparison of PAC levels across a broad range of cranberry products. Current use of procyanidin A2 as a standard leads to an underestimation of PACs content in certain cranberry products, especially those containing higher molecular weight PACs. To begin to address the issue of accuracy, a method for the production of a cranberry PAC standard, derived from an extraction of cranberry (c-PAC) press cake, was developed and evaluated. Use of the c-PAC standard to quantify PAC content in cranberry samples resulted in values that were 2.2 times higher than those determined by procyanidin A2. Increased accuracy is critical for estimating PAC content in relationship to research on authenticity, efficacy, and bioactivity, especially in designing clinical trials for determination of putative health benefits.

Influence of mealybug (Pseudococcus spp.)‐infested bunches on wine quality in Carmenere and Chardonnay grapes

SummaryThis study evaluated the effects of processing grape with different proportions of mealybug‐infested bunches in wine quality in cultivars Chardonnay and Carménère. No differences in chemical composition of musts were found. Basic chemical composition for white and red wines was similar. In both cultivars total polyphenols decreased as the proportion of infested bunches increased, from 266 to 239 (mg L−1 gallic acid) in Chardonnay and 2124 to 1820 in Carménère. The same trend was observed in Carménère for anthocyanins and tannins, by spectrophotometry and high performance liquid chromatography. Dimethyl amino cinnamaldehyde index in Carménère went from 28.6 in wines 100% healthy bunches to 22.0 for the 100% infested, and tannin galoilation went from 3.85 to 0.74%. Sensory analysis showed that wines with larger proportion of infested grapes were associated with negative descriptors and lower quality. These results show that mealybugs have the potential of negatively impacting wine quality and this deserves further attention.