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The purpose of this paper is to prepare, analyse and measure the colour values of the lake pigments obtained from the reaction of Al3+, Fe2+ and Sn2+ metal salts with the natural dyes present in European buckthorn (Rhamnus cathartica L.).

A reversed‐phase high performance liquid chromatography (HPLC) with diode‐array detection method was utilised for the identification of buckthorn lake pigments. The extraction of dyes from the lake pigments was carried out with 37% hydrochloric acid/methanol/water (2:1:1; v/v/v) solution.

According to the results of the HPLC analysis of the lake pigments, it was determined that rhamnetin, kaempferol, and emodin were present in the acid hydrolysed plant extract and in the lake pigment that was precipitated by Sn(II), quercetin‐3‐arabinosid, rhamnetin, and emodin were present in the non‐hydrolysed plant extract, and kaempferol, rhamnetin, isorhamnetin, and emodin were found in the lake pigment that was precipitated by Al(III). Rhamnetin and emodin were present in the lake pigment that was precipitated by Fe(II).

In the present context for the preparation of buckthorn lake pigments, a simple and practical method is presented. In addition, the analysis of the lake pigments was performed by reversed phase HPLC (RP‐HPLC) with diode array detector (DAD).

The paper describes the preparation of lake pigments and their qualitative analysis. This method can be used to determine the origins of the dyestuffs used in historical art pieces.

The paper describes the development of methods for the analysis and the preparation of European buckthorn lake pigments.

The present study has employed a high performance liquid chromatographic method coupled with a diode array detector (HPLC-DAD) to identify the dyestuffs in textile samples collected from the Coptic Museum in Cairo and the Museum of Jordanian Heritage. The results indicate that mixtures of organic dyes are used in dyeing these samples to produce different colours. The most dominantly identified colourants in samples collected from the Museum of Jordanian Heritage are laccaic acid, kermesic acid, munjistin and indigotin. The most dominantly identified dyestuffs are lac dye (Kerria lacca, Kerr), kermes (Kermes vermilio), madder (Rubia) species and indigoid dye source, either indigo (Indigofera species) or woad (Isatis tinctoria L.). These results confirm the historical information in the Museum of Jordanian Heritage in that the tested textile objects date back to the end of the 19^th century or the beginning of the 20^th century. The most dominantly identified colourants in samples collected from the Coptic Museum are alizarin, purpurin, and indigotin. The most dominantly identified dyestuffs are madder and indigotin. Based on this investigation, it is concluded that the tested dyed samples collected from the Coptic Museum belong to the 6-7^th centuries. This conclusion is in agreement with the initial dating of samples according to the style of the decorations.

The purpose of this paper is to highlight the health benefits, functional role of alpha linolenic acid (ALA) in combating diet-related non-communicable diseases, absorption, metabolism, toxicity and extraction of ALA.

A wide range of publications were identified through electronic databases (Google Scholar, PubMed, SciELO, ScienceDirect, SpringerLink and ResearchGate) on the basis of different keywords such as dietary sources, functional role, metabolism, beneficial effects, toxicity and extraction.

ALA, an omega-3 fatty acid, is commonly found in dietary sources such as flaxseeds, rapeseed, pumpkin seeds, walnuts and fatty fish, with flaxseed being the richest among all the sources. Several convincing evidences depict the functional role of ALA in ameliorating cardiovascular functions, regulating systolic and diastolic blood pressure and improving neurological disorders, thus possessing anti-arrhythmic as well as anti-inflammatory properties. Its promising effect is also noticed on post-menopausal symptoms like hot flashes, insomnia and headache as well as in balancing the levels of sex hormones in women suffering from PCOS. Furthermore, it was also responsible for reducing the concentrations of C-reactive protein and interleukin-6. Its excess consumption may lead to gastrointestinal disturbances such as flatulence and bloating. Various extraction techniques, namely, medium pressure liquid chromatography, silver silica gel chromatography, silver ion-solid phase extraction and silver ion-high pressure liquid chromatography are used for the extraction of ALA from its sources.

This is a novel review which will provide a brief overview of dietary sources, functional role, absorption and metabolism, health benefits, toxicity and extraction of ALA.

The purpose of this paper is to focus on the antioxidant properties of two phenolic-rich varieties of Nigerian local rice and their anti-cholinesterase potential after in vitro-simulated gastrointestinal digestion, with the aim of establishing their actual antioxidant and nutraceutical potential after their passage through the gastrointestinal tract upon consumption.

Two local rice varieties, commonly referred to as “Gboko” and “Ofada” rice commonly grown in Benue State, a middle belt region of Nigeria and south western regions of Nigeria, respectively, were locally processed. Each of the processed grains were divided into two portions; one portion was left uncooked, while the second portion was boiled conventionally as eaten, dried and subsequently milled into powder. The milled samples of the raw and boiled rice were treated with acidified methanol to obtain the methanol extracts; another portion of each samples was subjected to in vitro enzyme digestion using standard methods to mimic human digestion; and the third portion was treated using the same scheme of in vitro digestion without the sets of enzyme which was used to serve as a control for enzyme treatment. The quali-quantitative phenolic profiles of the two local varieties were carried out with the aid of high-performance liquid chromatography with diode-array detection (HPLC-DAD) method. The antioxidant potential and anti-cholinesterase action of the methanolic extracts, the simulated in vitro digested model and the enzyme-treated controls of the rice samples were determined using standard methods and data obtained were subjected to ANOVA; the differences of means were separated using Duncan’s multiple range test (DMRT).

The quali-quantitative assessment of phenolic compounds in the two studied local varieties revealed the presence of some phenolic acids and flavonoids, with a decreased level of most of the identified phenolic compounds after boiling. In vitro enzyme-digested rice for both raw and boiled rice samples showed significantly higher total phenolic content, total flavonoid content, ferric-reducing antioxidant power, 2, 2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS+) scavenging and NO− inhibitory activities than the aqueous-methanolic extracts and the enzyme-treated controls. The aqueous-methanolic extracts displayed a higher 1, 1 diphenyl-2-picrylhdrazyl radical scavenging activity and inhibited Fe2+-induced lipid oxidation in rat’s brain and liver homogenate than that displayed by the in vitro enzyme-digested samples. In vitro enzyme-digested and boiled “Gboko” and “Ofada” rice and raw “Ofada” rice have the potential of inhibiting acetylcholine esterase (AChE) activity. While methanolic extracts of raw and boiled “Ofada” and “Gboko” rice exhibited the potential to inhibit butrylcholinesterase activity. The result of this paper indicates that the selected rice varieties possess antioxidant capacities which are better released after the simulated in vitro enzyme digestion; the result also showed the anti-cholinesterase potential of the studied rice grains and, therefore, they can be considered as nutraceutical health supplements.

The paper has demonstrated the antioxidant potentials of the phenolic-containing two Nigerian local rice varieties and established their anti-cholinesterase potential after simulated in vitro enzyme digestion.

Advancements in real-time water monitoring technologies permit rapid detection of water quality, and threats from waste loads. Water Framework Directive mandating the establishment of Member States’ water resources monitoring, presence of hazardous contaminants in effluents, and perception of vulnerability of water distribution system to attacks, have spurred technical and economic interests. The paper aims to discuss these issues.

As alternative to traditional analyzers, chemosensors, operate according to physical principles, without sample collection (online), and are capable of supplying parameter values continuously and in real-time. Their low selectivity and stability issues have been overcome by technological developments. This review paper contains a comprehensive survey of existing and expected online monitoring technologies for measurement/detection of pollutants in water.

The state-of-the-art in online water monitoring is presented. Application examples are reported. Monitoring costs will become a lesser part of a water utility budget due to the fact that automation and technological simplification will abate human cost factors, and reduce the complexity of laboratory procedures.

An overview of applicable instrumentation, and forthcoming developments, is given. Technological development in this field is very rapid, and astonishing advances are anticipated in several areas (fingerprinting, optochemical sensors, biosensors, molecular techniques). Online monitoring is becoming an ever-important tool not only for compliance control or plant management purposes, but also as a useful approach to pollution control and reduction, minimizing the environmental impact of discharges.

Chili pepper pods are a worldwide used and cultivated spice with a high economic and cultural importance. Bolivia is a center of origin and diversification of important crops including wild pepper varieties, but little is known about the chemical composition, antioxidant activity and the Scoville and bioactive compounds of these chili peppers. The purpose of this study was to contribute with new data about the chemical composition and the Scoville scale of Bolivian Chili peppers.

A total of 26 samples of Bolivian Chili peppers were extracted using distilled water and methanol. Total antioxidant capacity was determined by the ferric-reducing antioxidant power (FRAP) and by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods. The total phenolic content was determined by Folin and Ciocalteu. Carotene, protein and ashes were determined by Bolivian analytical norms. Capsaicin was determined by high-performance liquid chromatography. All determinations were expressed as mean values± standard deviation of six replicates measured over three days of one extract. All values were less than 5% of coefficient of variation. Principal component analysis was applied to reveal patterns in the data. PC1 and PC2 together explained 78% of the total variance.

The protein content (3.8–6.3 g/100 g of dw) and the antioxidant activity (88.2 to 374 by FRAP and 87.0 to 172 evaluated by ABTS) studied in these species revealed that the values were above the average reported in the literature. The amount of pungency or capsaicin content expressed as Scoville Heat Units were reported moderately highly and very highly pungent (5,696–148,800 g dw) in several of the Bolivian peppers which demonstrates a good potential for capsaicin extraction and different applications for industry and as food ingredients.

This manuscript presents an important and novel contribution to the knowledge of the chili peppers in the region.

This study aims to evaluate the effect of grape seed extract on the thermal oxidation of soybean oil.

Four treatments were used: soybean oil (SO), butylhydroxytoluene (BHT), antioxidant at concentration of 100 mg/kg in soybean oil (BHTSO), grape seed extract at a concentration of 100 mg/kg in soybean oil (Extract), and mixture at a concentration of 50 mg/kg of grape seed extract (Mixture) and 50 mg/kg of BHT in soybean oil subjected to 180°C for 20 h. The total phenolic compounds were quantified by spectrophotometry using the Folin-Ciocalteu reagent. The antioxidant activity was evaluated by the ABTS^•+, DPPH^• and FRAP acid systems. The fatty acid composition and phytosterols were determined by gas chromatography (GC) and tocopherols were determined by high-performance liquid chromatography.

Among the treatments studied, the Extract and the Mixture presented lower losses of total phenolic compounds, DPPH^• and FRAP, while BHTSO had an opposite effect. After 10 h of heating, the Mixture and the Extract were more effective in reducing the formation decomposition products, measured by the amount of total polar compounds. The Mixture resulted in higher retention of essential fatty acids at the end of heating. The Extract and Mixture showed higher retention rates of total tocopherols and the Mixture resulted in 338.71 mg/100 g (P ≤ 0.05) of total phytosterol after 20 h of heating.

Oils undergoing the heating process suffer major changes, requiring the addition of antioxidant compounds. As a result of the questioning on the use of chemical additives, research on natural antioxidants, as substitute to the synthetic ones, is increasing. Among the natural compounds with high antioxidant potential, the grape wastes such as its seeds are highlighted. Studies using grape seed extract are scarce.

The purpose of this study was to investigate the efficiency of low temperature fractional crystallization to increase polyunsaturated fatty acid (PUFA) content of fish oil. Effects of temperature, stages of crystallization, rate of cooling, agitation and addition of primary nucleus on separation efficiency were evaluated. Low temperature crystallization of triacylglycerols (TAGs) was used to increase PUFA content of fish oil (initial PUFA content ∼30 g/100 g oil).

To optimize the fractionation process, the effect of fractionation temperature (7, 5, 0 and −5°C), crystallization procedures, cooling rate, agitation and addition of primary nucleus on PUFA content was evaluated.

The best relationship between PUFA concentration (45.8 g/100 g oil) and PUFA yield (51.5 per cent) was attained by performing two-stage crystallization of TAGs at the final temperatures of 5 and 0°C under slow cooling rate (3°C h−1 for first fractionation procedure and 0.7°C h−1 for second stage, until the final fractionation temperature, 0°C, was reached) and slow agitation (3 rpm) and in the presence of primary nucleus, which resulted in 50 per cent increase in PUFA content over the original fish oil.

Determination of iodine and saponification values, refractive index, solid fat content, melting point, cholesterol content of original oil and final fractionated product with the highest PUFA ratio showed that fractionation significantly alters physical and chemical properties of the fraction.

Comparison of iodine value, saponification value, refractive index, solid fat content, melting point and cholesterol content of original oil and the final fractionated product (with the highest PUFA ratio) showed that the fractionation process significantly alters mentioned properties of the initial oil.

Carotenoids are pigments that have significant value as colorants and antioxidants in pharmaceutical, food, textile and cosmetic industries. Owing to its high demand, this study aims to identify ß-carotene producing bacteria from different terrestrial habitats of Jaipur region.

In this paper, standard isolation and purification process was used, followed by colony morphology and biochemical characterization of ß-carotene producing bacteria. ß-carotene concentration was determined quantitatively using spectrophotometric method.

Out of 43 isolates, 21 isolates showed peak range between 400 and 500 nm confirming the presence of carotenoids. Only one bacteria SAN-A has capacity to produce ß-carotene confirmed by the thin layer chromatography and high performance liquid chromatography (HPLC) with a yield of 1.68 mg/l. The 2, 2-Diphenyl-2-picrylhydrazil (DPPH) assay showed an IC50 value of 4.0 mg/ml.

The present study revealed the presence of ß-carotene producing bacteria in the soil of different terrestrial habitat of Jaipur region which can be exploited as an economical source for ß-carotene production.

An interesting article by Bauer and Briggs has described a means for predicting flow properties of high solids coatings formulated with and without flow control agents. The flow properties were studied, starting with spray application and continuing through until curing. The solvent content in the coating film was measured by high performance liquid chromatography as a function of time after spray. A kinetic model was used to determine the increase in molecular weight and correspondingly in viscosity during cross‐linking. The rheological behaviour of the polymer solutions, which contained a polymeric microparticle flow control agent was measured. Also, models were developed to calculate the sheer stress as a function of sheer rate for different coatings, and these were related to the concentration of the flow control agent. Finally, all of the above data were used to calculate the sag of coatings as a function of time after spray with and without flow control agents. Although the addition of a flow control agent reduces sag during baking, it also tends to inhibit levelling. Also, the appearance of the high solids coating containing the flow control agent is more sensitive to film thickness than are low solids coatings.