Acid Reagent Research Articles

Culture Condition for High Biomass Production of Probiotic Yeast Saccharomyces Boulardii SB2 in Shake Flask and 30 Littre Scale

Probiotic properties in vitroof the Saccharomyces boulardii SB2 yeast, was isolated from fruit at Cuc Phuong National Park were evaluated based on biological characteristics and tolerance in simulated intestinal conditions. In the present work, studies were carried out to improve cell growth kinetics to produce cell mass of this biotherapeutic yeast in shake flaskand 30-L bioreactor levels. In case of shake flask, the highest biomass was obtained under the culture conditions as YM medium, at 37oC, pH 6, inoculum concentration of 5 %, with shaking for 32 h; the best sources of carbon and nitrogen were found to be glucose and mixture of peptone, yeast extract, malt extract; cell dry weight and cell density reached 2.43 g L-1 and 109 CFU/ml repetitively. During 30-L bioreactor cultivation, the maximal cell mass in agitation speed of 200 rpm, aeration rate of 1.2 v v-1 min-1; at 32 h of incubation, was 3.58 g L-1 in pH controlled culture and 3.08 g L-1 in uncontrolled pH. This is considered as the first step for cell mass production of this probiotic yeast in industrial scale
 Keywords:
 Saccharomyces boulardii SB2, probiotic, biomass, shake flask, 30-L bioreactor.
 References
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Preparation and electrochemical properties of core-shelled silicon–carbon composites as anode materials for lithium-ion batteries

In this paper, core-shelled silicon–carbon composites as anode materials for lithium-ion batteries (LIBs) are prepared by a cost-effective method of the combined mechanical ball milling and high-temperature heat treatment. The microstructures and morphologies of such anode materials with different silicon contents are characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and thermogravimetric analysis. Both coin and soft-packed LIBs are fabricated using these silicon–carbon composites as anode materials. The batteries can give high capacities of 377.7 mA h g−1, 418.5 mA h g−1, 450.9 mA h g−1, and 500.1 mA h g−1 at the silicon contents of 2.0%, 6.5%, 9.5%, and 14.5%, respectively. The effects of silicon content on the coulomb efficiency, low-temperature capacity, resistance, and cycle life are also studied, and the results show that a silicon content of 9.5% can give the best battery performance. Considering that the process has no surfactant, corrosive acidic or alkaline reagent added, and that the ball milling and heat treatment are efficient, cost-effective, and environmentally friendly, it can be expected that the fabrication process described in this paper should be usable for large-scale production of silicon–carbon composite materials for anodes of LIBs.

Continuous synthesis of tetraethyl thiuram disulfide with CO2 as acid agent in a gas-liquid microdispersion system

Herein, a continuous synthetic method of tetraethyl thiuram disulfide (TETD) with CO2 as a weak acid reagent in a gas-liquid microdispersion reaction system has been described. A microdispersion reaction system comprising two microreactors for CO2 absorption and diethyldithiocarbamate acid subsequent oxidation reaction was developed. In the first step, the main products of absorption and oxidation reactions were identified. Next, the yield of TETD and selectivity of sodium diethyldithiocarbamate under different flow rates of raw materials, amount of CO2, aging effect, and pressure in the microreaction system were determined. The yield reached 89.03% based on 60% H2O2 dosage and the selectivity was 92.86% in less than 3 min of residence time, which was more than 30 min in the batch process. The space time yield in the microreaction system was ~20 times of that achieved in the batch process. The study provides a new successful reference for replacing batch synthesis by a continuous process using a microreaction system.

Sustainable technology for mass production of Ag nanoparticles and Al microparticles from damaged solar cell wafers

Solar cell industry produces high quantities of waste in form of broken, damaged, and rejected cells, whereas milling and filtering practices are typically used to recover the valuable materials (Al, Ag and Si) from such Waste Solar Cell Wafers (WSCWs). This recycling approach has its disadvantages, e.g. excessive energy consumption and dust emission causing loss of valuable metals. To fulfil the concept of Zero Waste for WSCWs, the authors present a sustainable technology for liberation of valuable metals from WSCWs and synthesis of added value products, in particular Ag nanoparticles and Al microparticles. The suggested technology consisted of three different approaches combined to liberate each material individually. The technology started with an Al layer disintegration process using Dimethyl Sulfoxide (as an eco-friendly and sustainable solvent) supported by ultrasonic treatment to break van der Waals’ bonding between spherical Al microparticles that compose the Al paste layer, thus liberating Al in microparticle suspension form with particle size ∼3 μm, recovery rate >98%. After that, leaching by nitric acid and other eco-friendly reagents (Sodium Chloride, Ammonia solution and glucose syrup) assisted by ultrasonic treatment was used to dissolve Ag and later precipitate it in form of nanoparticles with avg. size 30 nm, yield >92%. Finally, etching using paste containing phosphoric acid was done to remove anti-reflection coating and purify the Si substrate with final recovery rate >99%. SEM-EDS, XRD, FTIR, and TEM were used for analysis of extracted materials as well as changes in the solvent. Investigation was also concerned with determining economic/global warming impacts of the technology.

Validated UV-Vis Spectrophotometric Determination of Andrographolide in Herbal Nano-Preparation

Determination of major bioactive compounds in polyphyto-formulation is important for production of standardized herbal products. A fast, simple and inexpensive method for detection and quantification of andrographolide concentration in nanoemulsion preparations containing a combination of Andrographis paniculata (Burm f.) Ness. and Phyllanthus niruri L. has been developed. Detection and quantification were carried out using UV-vis spectrophotometry analysis with picric acid reagent and NaOH (8:2) in methanol solvents, read at maximum wavelength 479 nm with 22 min of incubation time. Validation was done by determine the parameters such as linearity, intra and interday precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). The results obtained showed linearity with r = 0.9945 (y = 0.0109x − 0.2066) in the range of 30-80 μg/mL. The accuracy (recovery) varied in the range of 97.15 to 104.42 %. Percentage of relative standard deviation (% RSD) for precision and intermediate precision value were 3.23 and 3.02 % with LOD value 211 μg/mL and the LOQ 705 μg/mL. As a conclusion, this method is suitable to detect andrographolide content in herbal nano-preparation.

Self-acidity induced effervescence and manual shaking-assisted microextraction of neonicotinoid insecticides in orange juice.

A novel dispersive liquid-liquid microextraction that combines self-induced acid-base effervescent reaction and manual shaking, coupled with ultra high performance liquid chromatography with tandem mass spectrometry was developed for simultaneous determination of ten neonicotinoid insecticides and metabolites in orange juice. An innovative aspect of this method was the utilization of the acidity of the juice for a self-reaction between acidic components contained in the juice sample and added sodium carbonate which generated carbon dioxide bubbles in situ, accelerating the analytes transfer to the extractant of 1-undecanol. The total acid content of juice sample was measured to produce the maximum amount of bubbles with minimum usage of carbonate. Manual shaking was subsequently adopted and was proven to enhance the extraction efficiency. The factors affecting the performance, including the type and the amount of the carbon dioxide source and extractant, and ionic strength were optimized. Compared with conventional methods, this approach exhibited low limits of detection (0.001-0.1µg/L), good recoveries (86.2-103.6%), high enrichment factors (25-50), and negligible matrix effects (-12.3-13.7%). The proposed method was demonstrated to provide a rapid, practical, and environmentally friendly procedure due to no acid reagent, toxic solvent, or external energy requirement, giving rise to potential application on other high acid-content matrices.

Ultrasound-assisted extraction of chromium from residual tanned leather: An innovative strategy for the reuse of waste in tanning industry.

The tannery industry generates huge amount of waste with high Cr concentration, being classified as a dangerous waste. The development of alternative treatments for these residues aiming environmental friendly protocols are important topics of research. In this work, the use of ultrasound (US) energy for Cr removal from residual tanned leather was investigated. Ultrasound-assisted extraction (UAE) experiments were carried out in several systems as ultrasonic baths, cup horns, and probes, allowing to evaluate several frequencies (20-130 kHz) and power delivered to the extraction system. The following experimental conditions were evaluated: extraction solution (HCl, HNO3, H2SO4, CH2O2 and C2H2O4), temperature (10-90 °C), time (1-40 min), US amplitude (10-90%), feedstock amount (50-450 mg), and concentration of extraction solution (0.1-4 mol L-1). A multivariate factorial design with 10 axial points and 3 central points was applied. After UAE optimization an efficiency of 92% was achieved for Cr removal using 150 mg of feedstock, 3 mol L-1 HNO3, at 30 °C, 90% of amplitude, and 30 min. The same efficiency was not observed using mechanical stirring (100-500 rpm), which was lower than 65%. To prove the applicability of the proposed process some experiments for scaling up were performed using several reactor loads (1-9 L). Moreover, using the proposed UAE process Cr was efficiently removed at lower reaction time and at room temperature only by using US and diluted acid solution, representing energy and reagents saving.

Solvent extraction separation and spectrophotometric determination of ruthenium(III) with p-methylphenyl thiourea: sequential separation of ruthenium, osmium and iron

ABSTRACT A selective and sensitive solvent extraction and spectrophotometric study of the ruthenium(III)–p-methylphenyl thiourea (PMPT) system is presented. The optimum conditions were determined by a critical study of acid concentration, reagent concentration, equilibration period, heating time and effect of solvent on the equilibrium. Ruthenium(III) forms 1:1 complex with PMPT in 20% ethanol and extracted into chloroform. Conformity to Beer’s law at 600 nm was observed up to 40 µg mL–1 of ruthenium. Molar absorptivity and Sandell’s sensitivity were found to be 2.31 × 103 L mol−1cm−1 and 0.044 μg cm−2, respectively. The detection limits were 0.11 μg mL−1 of ruthenium. The method is free from interferences from large number of cations and anions. Proposed method was successfully applied to the separation and determination of ruthenium from synthetic alloys, catalyst and water samples. Sequential separation and determination method for ruthenium(III), osmium(VIII) and iron(II) has been developed.

Thin Layer Chromatographic Identification of the Whole Plant of Sangketan (Achyranthes Aspera)

Medicine plant is a great source of information for variety of phytochemicals which can be developed as drug with the right selectivity. One of the potential plants developed as anticancer drugs is Sangketan (Achyranthes aspera). In the in vivo study showed that Achyranthes aspera causes apoptosis and healing to breast cancer cells induced by benzopyrene. This study deals with early phytochemicals screening using thin layer chromatography of Achyranthes aspera. Sangketan powder is extracted by reflux method on water bath with temperature of 50°C using ethanol, methanol and petroleum ether solvent. The extract from filtering is concentrated on water bath using porcelain dish. After obtaining the extract concentrated, it is dissolved with a suitable solvent, then elluted on Silica Gel 60 F254 stationary phase with various mobile phase comparison (chloroform : methanol). In qualitative analysis, phytochemical compounds such as steroids, triterpenoid, sugar, alkaloids, phenolic compounds, flavonoids were extracted in Sangketan using standard methods. The screening uses thin layer chromatography with chloroform : methanol of (8: 2 v / v), showing some gray bands after spraying vanillin - sulphate acid reagent. This result reveals that Achyranthes aspera is an important source of various active therapeutic and pharmacological properties.

Non-Dispersive Extraction of Ge(IV) from Aqueous Solutions by Cyanex 923: Transport and Modeling Studies

Transport process of germanium from an aqueous solution containing oxalic acid and 100 mg/L Ge was studied. Cyanex 923 immobilized in a polytetrafluoroethylene membrane was employed as a carrier in a flat-sheet supported liquid membrane (FSSLM) system. The speciation of the germanium ion in the oxalic acid medium and related diagrams were applied to study the transport of germanium. The effective parameters such as oxalic acid, carrier concentration, and strip reagent composition were evaluated in this study. Based on the experimental data, the oxalic acid and carrier concentrations of 0.075 mol/L and 20% v/v were the condition in which the efficient germanium transport was achieved, respectively. The concentration range of 0.04–0.1 mol/L was selected for sodium hydroxide (NaOH) as a strip reagent providing the best efficiency to transport germanium through the supported liquid membrane (SLM) system. Furthermore, the permeation model was obtained to calculate the mass transfer resistance of the membrane (Δm) and feed (Δf) phases. According to the results, the values of 1 and 1345 s/cm were found for Δm and Δf, respectively.

Aerobic Acyloxylation of Allylic C-H Bonds Initiated by a Pd0 Precatalyst with 4,5-Diazafluoren-9-one as an Ancillary Ligand.

Palladium-catalyzed allylic C-H oxidation has been widely studied, but most precedents use acetic acid as the coupling partner. In this study, a method compatible with diverse carboxylic acid partners has been developed. Use of a Pd0 precatalyst under aerobic reaction conditions leads to oxidation of Pd0 by O2 in the presence of the desired carboxylic acid to generate a PdII dicarboxylate that promotes acyloxylation of the allylic C-H bond. Good-to-excellent yields are obtained with a roughly 1:1 ratio of the alkene and carboxylic acid reagents. Optimized reaction conditions employ 4,5-diazafluoren-9-one (DAF) as a ligand, in combination with a quinone/iron phthalocyanine cocatalyst system to support aerobic catalytic turnover.

Multicomponent synthesis of α-acylamino and α-acyloxy amide derivatives of desmycosin and their activity against gram-negative bacteria.

Bacterial resistance to the existing drugs requires constant development of new antibiotics. Developing compounds active against gram-negative bacteria thereby is one of the more challenging tasks. Among the many approaches to develop successful antibacterials, medicinal chemistry driven evolution of existing successful antibiotics is considered to be the most effective one. Towards this end, the C-20 aldehyde moiety of desmycosin was modified into α-acylamino and α-acyloxy amide functionalities using isonitrile-based Ugi and Passerini reactions, aiming for enhanced antibacterial and physicochemical properties. The desired compounds were obtained in 45-93% yield under mild conditions. The antibacterial activity of the resulting conjugates was tested against gram-negative Aliivibrio fischeri. The antibiotic strength is mostly governed by the amine component introduced. Thus, methylamine derived desmycosin bis-amide 4 displayed an enhanced inhibition rate vs. desmycosin (99% vs. 83% at 1 µM). Derivatives with long acyclic or bulky amine and isocyanide Ugi components reduced potency, whereas carboxylic acid reagents with longer chain length afforded increased bioactivity. In Passerini 3-component products, the butyric ester amide 22 displayed a higher activity (90% at 1 µM) than the parent compound desmycosin (2).

Controlling fingermark variability for research purposes: A review

AbstractFingermark detection is a very active field of research in forensic science, with many different strategies currently investigated to always improve detection rate. However, each new technique has first to be optimized, assessed and validated with many fingermarks from multiple donors across a wide variety of substrates before being included into laboratories operating procedures. This process often requires the collaboration of research groups and operational laboratories from different countries, and it takes several years for a new method to be applied routinely in casework. One particular challenge that makes the process from R&D to operations complicated is the significant intrinsic within‐ and between‐source variability of fingermarks. Many studies partially addressing fingermark variability have been reported but a comprehensive approach to the problem is yet to be found. This review describes the factors of fingermark variability and provides an extensive overview of various strategies implemented to control it. The use of artificial fingermarks or simulants, containing some of the most abundant compounds found in fingermark residue has been investigated by some research teams. However, most of these formulations are too simplistic and can only be used to assess a restrictive number of detection techniques, such as amino acid reagents. Practical applications of artificial fingermarks such as test strips and proficiency testing are reviewed. The advantage and challenges of using artificial fingermarks in the first stages of fingermark detection research are presented.This article is categorized under: Forensic Chemistry and Trace Evidence > Fingermarks and Other Marks

Catalytic and Enantioselective Diels‐Alder Reaction of Siloxydienes

AbstractDiels‐Alder reaction is one of the most well‐known named reactions in organic chemistry. It involves a diene substrate and a dienophile substrate. Among dienes, siloxydiene is a reactive substrate that is often used in Diels‐Alder reaction. In general, Diels‐Alder reaction is promoted by an acidic reagent. In many cases, the stereoselectivity of the reaction is also controlled by acids. However, siloxydienes are labile under acidic conditions. Thus, it should be difficult to develop a reaction using siloxydiene as a substrate. Nevertheless, siloxydienes are still used in synthetic organic chemistry, and most reactions are performed under thermal activation conditions. In this minireview, we summarize the reported examples of catalytic and enantioselective Diels‐Alder reactions of siloxydienes based on the structure of the diene. We present the activation methods used, the existing problems, and a clue for the further development of this annulation chemistry.

Improving a procedure for determining the assay of gold in a precious alloy of different composition using a touchstone

We report testing the and jewelry alloys based on that contains nickel, zinc, palladium, using a touchstone by applying various chemical reagents and XFA (X-ray fluorescence analysis).We have improved the procedure for assessing the conformity of assay of the precious alloys based on considering the content of component composition by using the results from rubbing the alloys on a touchstone.It was established that the magnitude of assay for precious alloys in the system AuAgZnCu, determined under the action of the reagent chloric gold on the touchstone, depends on the manifestation of contrast in the course of quality reaction against a standard sample (touch-needle).Under the influence of the reagent, the alloys demonstrate chloride compounds with silver and copper, being reduced to a metal powder of black and brown color. In this case, copper dissolves while together with silver, forms an intensive residue on a strip that depends on the ligature composition of the alloy. It was established that the lower the assay of a tested sample, the greater the amount of chlorine gold that decomposes, the larger the sediment of silver chloride and the pure reduced from the reagent, and hence the darker the sediment.It has been proven that testing the precious alloys of red color from the system AuAgZnCu 585 with a content of zinc (over 2 %), nickel, indium by using a reagent based on potassium dichromate and copper chloride is not effective.The results of our analysis indicate the increased assay compared with a standard touch-needle.To eliminate this phenomenon, it is recommended that one should first determine the composition of an alloy by the XFA method and construct an algorithm for testing in accordance with the content of the alloy by other reagents.It was determined that the assay defined on a touchstone for alloys from the system AuAgZnCu 585 (a content of zinc is over 2 %) is more contrast under the influence of acidic reagents and depends on the component composition of the alloy.It has been proven that the alloy of white gold, composed of palladium and silver (AuAgPd585), is not affected by the acid reagent for assay 585.Testing the alloy of white gold (AuAgPd585) using an acid reagent for assay 750 yields the dark sediment of a bluish tint.We have established a more contrast effect on the alloys of white gold and yellow gold of assay 750 from the acid reagent for alloys of assay 750.

Noble-Metal-Free Visible Light Driven Hetero-structural Ni/ZnxCd1−xS Photocatalyst for Efficient Hydrogen Production

Ni/ZnxCd1−xS composite photocatalyst was successfully synthesized by hydrothermal method and in situ photodeposition method, and certain hydrogen evolution results were obtained in acidic, neutral and alkaline sacrificial reagents. Among them, hydrogen evolution amount reached 11.993 mmol h−1 g−1 in alkaline Na2S/Na2SO3 solution. According to SEM, TEM and Mapping, two solid solutions of ZnxCd1−xS were formed under specific reaction conditions, which provided a large specific surface area and increased the contact area between metal Ni and ZnxCd1−xS, leading to more electron transfer. The UV–Vis diffuse reflectance spectra indicates that, due to the interface interaction between Ni and ZnxCd1−xS, the photodeposition of Ni leads to the reduction of the band gap of the photocatalyst, the expansion of visible light absorption range, and the generation of more photogenerated electrons. The excellent electron transport ability of Ni leads to the rapid separation of electron–hole pairs, inhibits the recombination of electron–hole pairs, and greatly improves the photocatalytic activity. This work describes the effective synergistic effect of Ni/ZnxCd1−xS photocatalysis, showing good hydrogen evolution effect, and emphasizes the excellent electronic conductivity without noble metal synergistic catalyst.

Significant Polar Comonomer Enchainment in Zirconium‐Catalyzed, Masking Reagent‐Free, Ethylene Copolymerizations

AbstractIn principal, the direct copolymerization of ethylene with polar comonomers should be the most efficient means to introduce functional groups into conventional polyolefins but remains a formidable challenge. Despite the tremendous advances in group 4‐centered catalysis for olefin polymerization, successful examples of ethylene + polar monomer copolymerization are rare, especially without Lewis acidic masking reagents. Here we report that certain group 4 catalysts are very effective for ethylene + CH2=CH(CH2)nNR2 copolymerizations with activities up to 3400 Kg copolymer mol−1‐Zr h‐1 atm‐1, and with comonomer enchainment up to 5.5 mol % in the absence of masking reagents. Group 4 catalyst‐amino‐olefin structure–activity‐selectivity relationships reflect the preference of olefin activation over free amine coordination, which is supported by mechanistic experiments and DFT analysis. These results illuminate poorly understood facets of d0 metal‐catalyzed polar olefin monomer copolymerization processes.

Significant Polar Comonomer Enchainment in Zirconium-Catalyzed, Masking Reagent-Free, Ethylene Copolymerizations.

In principal, the direct copolymerization of ethylene with polar comonomers should be the most efficient means to introduce functional groups into conventional polyolefins but remains a formidable challenge. Despite the tremendous advances in group 4-centered catalysis for olefin polymerization, successful examples of ethylene + polar monomer copolymerization are rare, especially without Lewis acidic masking reagents. Here we report that certain group 4 catalysts are very effective for ethylene + CH2 =CH(CH2 )n NR2 copolymerizations with activities up to 3400 Kg copolymer mol-1 -Zr h-1 atm-1 , and with comonomer enchainment up to 5.5 mol % in the absence of masking reagents. Group 4 catalyst-amino-olefin structure-activity-selectivity relationships reflect the preference of olefin activation over free amine coordination, which is supported by mechanistic experiments and DFT analysis. These results illuminate poorly understood facets of d0 metal-catalyzed polar olefin monomer copolymerization processes.

Characterization of Pharmacognostical and Preliminary Phytochemical Features of Tubers of Dioscorea oppositifolica L.

Journal of Ayurveda Medical Sciences,2018,3,3,413-419.DOI:10.5530/jams.2018.3.21Published:April 2019Type:Original ArticleAuthors:Ravikrishna Sagri, Shrikanth Padigar, Tantrady Shridhara Bairy, and Suchitra Narayan Prabhu Author(s) affiliations:Ravikrishna Sagri *, Shrikanth Padigar, Tantrady Shridhara Bairy, Suchitra Narayan Prabhu1 Department of Dravyaguna, Sri Dharmasthala Manjunatheshwara College of Ayurveda and Hospital, 1Department of Pharmacognosy and Phytochemistry, Sri Dharmathala Manjunatheshara Centre for Research in Ayurveda and Allied Sciences, Kuthpady, Udupi 574118, India. Abstract:Introduction: Ayurveda opines that the plants which are grown in one’s own vicinity should be used for food and medicinal needs, though beneficial either as food or as medicine there are many less explored plants. Rare knowledge on folklore plants is passed on from generations to generations traditionally. One such plant is Dioscorea oppositifolia L. (Dioscoreaceae) found frequently in and around Udupi locally known as Kaadu genasu. The plant is large climber with numerous cylindrical tubers which are consumed as food as it is very nutritive and used as food during famine. On account of these utilities of this less explored plant material, a detailed pharmacognostical study including macro and microscopy was conducted. Methods: Tubers of D. oppositifolia L. was subjected to organoleptic, macro microscopic, physicochemical, HPTLC , nutritional values assessment, characterization employing standard methodology mentioned in pharmacopoeia and other herbal analysis protocols. Results: The matured tubers of D. oppositifolia L. is on an average 25 cm in length 3 to 4 cm in diameter; cylindrically elongated; outer surface is off white with lot of rootlets and cut inner surface is white and mucilaginous. TS of tuber consists of 3 to 5 layers of thin-walled cork cells, followed by cortex formed from thin-walled parenchyma having lot of starch grains; ground tissue consists of parenchyma cells consisting of cells with contents, starch grains and acicular crystals; endodermis layer which is distinct is present following cortex; groups of scattered vascular bindles, comprising of vessels with crown of phloem patches occur towards the inner regions. Preliminary phytochemical study revealed the presence of alkaloids, steroids, carbohydrates and saponins. HPTLC photo documentation showed. No spot under short UV, 4 bands under long UV and 5 bands under white light after derivatisation with vanillin sulphuric acid reagent. Conclusion: Results of this study can be utilized for identification of the drug as well as systematic document on purity standards of this extra pharmacopoeial drug. Keywords:Dioscoreaceae, Folklore, Kaadu genasu, Pharmacopoeia, StandardizationView:PDF (2.92 MB)

HPTLC, HPTLC-MS/MS and HPTLC-DPPH methods for analyses of flavonoids and their antioxidant activity in Cyclanthera pedata leaves, fruits and dietary supplement

HPTLC silica gel, amino and C18 plates in combination with different developing solvents were explored for the first HPTLC chemical profiles of flavonoids and sugars in crude extracts from leaves and fruits of caigua (Cyclanthera pedata Scrabs) harvested in Slovenia and Italy. New HPTLC and HPTLC-MS methods for analyses of flavonoids are based on HPTLC silica gel (preconditioned with water) or C18 plates in combination with developing solvents ethyl acetate–water–formic acid (17:3:2, v/v) or 5% formic acid in methanol-water (7:3, v/v), respectively. Detection was performed before (for flavonoids) and/or after post-chromatographic derivatization with Natural product (NP) reagent for flavonoids and diphenylamine-aniline-phosphoric acid (DAP) reagent for sugars. HPTLC–MS/(MSn) analyses on silica gel and C18 stationary phases enabled tentative identification of several compounds in crude extracts from leaves and fruits. HPTLC-DPPH• assay combined with image analyses and HPTLC–MS/(MSn) analyses, applied for direct screening of antioxidant activity of separated chromatographic zones (compounds) on HPTLC silica gel plates, confirmed activity in several zones of all crude extracts, in which some active compounds were tentatively identified. Apigenin 6-C-glucoside (isovitexin) and luteolin 8-C-glucoside (orientin) were found in all crude extracts, but the last was the most active free radical scavenger. Both compounds were also identified in dietary supplement product produced from caigua fruits. Crude extracts from leaves showed much higher antioxidant activity than those from fruits. The highest antioxidant activity was determined for crude extract from leaves harvested in Slovenia, while among crude extract from fruits the highest activity was determined for the extract from fruits harvested in Italy.