Thermal Stability and Inhibitory Action of Red Grape Skin Phytochemicals against Enzymes Associated with Metabolic Syndrome

The present study focuses on heat-induced structural changes and the degradation kinetics of phytochemicals and antioxidant activity of red grape skin extract. The thermal degradation of anthocyanins, flavonoids, polyphenols, and antioxidant activity followed a first-order kinetic model, increasing with temperature due to the intensification of the degradation process. The activation energy (Ea) highlighted this phenomenon. Likewise, the kinetic and thermodynamic parameters certified the irreversible degradation of the bioactive compounds from the skin of the Băbească neagră grape variety. Both temperature and duration of heating had a significant impact on the content of bioactive compounds. In addition, the red grape skin extract inhibited certain enzymes such as α-amylase, α-glucosidase, lipase, and lipoxygenase, which are associated with metabolic syndrome and inflammation. Further knowledge on the possible inhibition mechanisms exerted by the major anthocyanins found in red grape skin extract on the metabolic syndrome-associated enzymes was gathered upon running molecular docking tests. Detailed analysis of the resulting molecular models revealed that malvidin 3-O-glucoside binds in the vicinity of the catalytic site of α-amylase and lipase, whereas no direct contact with catalytic amino acids was identified in the case of α-glucosidase and lipoxygenase.

Increasing the Yield of Powder and Bioactive Materials during Extraction and Spray Drying of Dragon Fruit Skin Extracts

One potential utilization of dragon fruit skin is to produce bioactive materials as natural antioxidants and colorants for the food industry by extraction and spray drying. This study investigated the quality (total phenolic compounds/TPC, betacyanin and betaxanthin contents, and antioxidant activity) of the extracts and spray-dried products, and the quantity (powder yield) obtained by the use of different types and amounts of spray drying agents. Two drying agents were introduced during spray drying, i.e. maltodextrin and whey protein isolate (WPI). The result showed that a lower extraction solvent to solid ratio may result in a lower yield of TPC, betacyanin and betaxanthin contents, and also in antioxidant activity of the dragon fruit skin extract. In addition, maltodextrin and WPI were found to be able to significantly increase the yield from spray drying. The highest yield (72.7 ± 8.4%) was obtained with the use of 40% maltodextrin as drying agent, while the control yielded 9.5 ± 1.8%. Furthermore, it was found that the spray-dried product could recover more than 90% of the TPC and betacyanin in the extracts, which indicates that spray drying may be suitable for heat-sensitive materials.

Evaluating the Effectiveness of Red Onion Skin Extract Derivatives as Oilfield Scale Inhibitors

With growing awareness of the environmental impact of some conventional production chemicals and concerns about the depletion of non-renewable natural resources, increased efforts are being made to use renewable and non-toxic materials in the oilfield. In this study, a potential green scale inhibitor was developed from the skin of red onions and evaluated for calcium sulphate, calcium carbonate and barium scale inhibition. Based on the different extraction processes utilized, two products were obtained and characterized using FTIR and SEM and evaluated using a static jar test procedure. The FTIR results confirmed the bands that make up the major constituents (quercetin) and other important compounds, which supports the present study. Laboratory evaluation show that ROSE can efficiently inhibit calcium sulphate scale and barium sulphate scales with a good inhibition rate of greater than 75% at an optimum dosage. Effect of temperature and dosage on inhibition performance revealed that ROSE is stable at higher temperatures and can effectively inhibit calcium and barium sulphate scales at nearly the same rate without degradation but requires additional dosage to produce same result for calcium carbonate scale. Also, the effect of time reveals that scale inhibitor performs a continuous CaSO4 and CaCO3 inhibition. Not only does ROSE perform excellently in the laboratory condition as a green scale inhibitor, but it also show a relatively close performance rate when compared to an existing commercial inhibitor which indicate that ROSE has a high potential for use in the oil industry.

Syrah Grape Skin Residues Has Potential as Source of Antioxidant and Anti-Microbial Bioactive Compounds

In this study, we evaluated the effects of ultrasound-assisted extraction (UAE) under different time-temperature conditions on the content of bioactive compounds, antioxidant and antimicrobial activities of Syrah grape skin residue. The application of UAE showed a positive effect on the extraction of total flavonoids, and a negative effect on total polyphenols. The temperature of 40 °C and 60 °C without the UAE caused an increase of 260% and 287% of the total polyphenols, respectively. Nineteen individually bioactive compounds were quantified. The anthocyanin concentration (malvidin-3,5-di-O-glucoside 118.8–324.5 mg/100 g) showed high variation, to a lesser extent for phenolic acids, flavonoids, flavonols, procyanidins and stilbenes due to the UAE process. The Syrah grape skin residue has a high concentration of total phenolic compounds of 196–733.7 mg·GAE/100 g and a total flavonoid content of 9.8–40.0 mg·QE/100 g. The results of free radical scavenging activity (16.0–48.7 mg/100 mL, as EC50) and its inhibition of microbial growth (0.16 mg/mL, as EC50 for S. aureus, and 0.04 mg/mL, as EC50 for E. coli) by grape skin extract (UAE 40:20) indicate high antioxidant and antibacterial activity. It was concluded that the use of ultrasound needs further analysis for its application in this context, as it has shown deleterious effects on some compounds of interest. Syrah grape skin residue has potential as a source of bioactive antioxidants, antimicrobial activity and for use as a functional food ingredient.

Behavioural responses to con- and heterospecific alarm cues by an alien and a coexisting native fish

The monkey goby Neogobius fluviatilis is an invasive Ponto-Caspian fish that enters habitats of the native gudgeon Gobio gobio in European freshwaters, likely belonging to the same prey guild. Their abilities to detect and avoid predation have been poorly understood, although these traits may contribute to the competitive advantage and drive the invasion success of the goby. We tested intra- and interspecific responses of fish from sympatric populations to damage-released alarm cues (skin extract) in laboratory. Both species of fish responded to conspecific and heterospecific cues, but their responses to conspecifics were more diverse (changed social distancing among individuals, reduced vertical and horizontal movement) than those elicited by heterospecifics (changed social distancing only). Moreover, the fish differed in their anti-predation behaviour: the gudgeon increased whilst the monkey goby decreased inter-individual distances and only the gudgeon exhibited thigmotaxis and reduced mobility in response to the conspecific cues. Interspecific differences show that the species exhibit distant anti-predation strategies. This might be associated with their phylogenetic distance and/or higher differentiation of their ecological niches than commonly assumed. Besides, our results suggest that alien species be included in the interspecific exchange of information in local fish assemblages.

Antioxidant Power on Dermal Cells by Textiles Dyed with an Onion (Allium cepa L.) Skin Extract

In this study, the phenol loading and antioxidant activity of wool yarn prepared with the aqueous extract of onion (Allium cepa L.) skin was enhanced by implementing the dyeing process with the use of alum as a mordant. Spectrophotometric and chromatographic methods were applied for the characterization of polyphenolic substances loaded on the wool yarn. The antioxidant/anti-inflammatory properties were evaluated by determining the level of intra- and extra-cellular reactive oxygen species (ROS) production in keratinocytes and dermal fibroblasts pre-treated with lipopolysaccharide put in contact with artificial sweat. An elevated dye uptake on wool was observed for the pre-mordanted sample, as demonstrated by high absorbance values in the UV-Visible spectral range. Chromatographic results showed that protocatechuic acid and its glucoside were the main phenolic acid released in artificial sweat by the wool yarns, while quercetin-4′-glucoside and its aglycone quercetin were more retained. The extract released from the textile immersed in artificial sweat showed a significant reducing effect on the intra-and extracellular ROS levels in the two cell lines considered. Cytofluorimetric analyses demonstrated that the selected mordant was safe at the concentration used in the dyeing procedure. Therefore, alum pre-mordanted textiles dyed with onion-skin extracts may represent an interesting tool against skin diseases.

FORMULASI SEDIAAN LOTION SEBAGAI TABIR SURYA DARI EKSTRAK METANOL KULIT LUAR BUAH JENGKOL (Archidendron jiringa (jack) I.C.Nielsen)

Sunscreen is a chemical or ingredient that contains elements that protect the skin from the harmful effects of direct sunlight. The flavonoid molecules in the jengkol fruit's outer skin have a conjugated aromatic benzene group, which can absorb UVA or UVB radiation and cause skin damage. The goal of this study is to figure out what concentration of methanol extract of the outer skin of jengkol fruit (100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm) gives the best SPF value and what effect that concentration has on the outer skin of jengkol fruit as an active ingredient in sunscreen preparations. Using spectrophotometry, the efficacy of a methanol extract of the outer skin of the jengkol fruit as an active component in sunscreen was assessed at concentrations of 100 ppm, 150 ppm, 200 ppm, 250 ppm, and 300 ppm. The methanol extract of the jengkol fruit's outer peel had a concentration of 300 ppm (SPF value 4.783) and was divided into three formulae with concentrations of 0.3 (F1), 0.45 (F2), and 0.65 (F3) (F3). Physical, chemical, stability, and SPF quality of the resulting formulations were evaluated. Each jengkol fruit outer skin extract lotion formulation was shown to be effective as a sunscreen, with SPF values of 27.90 (F1), 8.46 (F2), and 15.56 respectively (F3)ABSTRAKTabir surya adalah zat atau ramuan yang mengandung bahan kandungan pelindung kulit terhadap paparan sinar matahari langsung yang dapat menyebabkan gangguan kulit. Senyawa flavonoid dalam kulit luar buah jengkol memiliki gugus benzene aromatic terkonjugasi yang dapat menyerap sinar UVA atau UVB serta dapat menyebabkan efek buruk terhadap kulit. Penelitian ini bertujuan untuk menentukan konsentrasi ekstrak methanol kulit luar buah jengkol (100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm) yang memberikan nilai SPF paling baik dan mengetahui pengaruh konsentrasi ekstrak metanol kulit luar buah jengkol sebagai bahan aktif sediaan tabir surya. Ekstrak metanol kulit luar buah jengkol dengan menggunakan konsentrasi 100 ppm, 150 ppm, 200 ppm, 250 ppm, dan 300 ppm yang ditentukan efektivitasnya sebagai bahan aktif tabir surya menggunakan spektrofotometri. Ekstrak metanol kulit luar buah jengkol dengan konsentrasi 300 ppm (nilai SPF 4,783) diformulasikan dalam tiga formula dengan variasi konsentrasi 0,3 (F1), 0,45 (F2), 0,65 (F3). Sediaan yang diperoleh dievaluasi mutu fisik, kimia, stabilitas, dan SPF. Masingmasing formula lotion ekstrak kulit luar buah jengkol ditentukan efektifitasnya sebagai tabir surya dan mendapatkan nilai SPF 27,90 (F1), 8,46 (F2) dan 15,56 (F3).

Skirining fitokimia ekstrak etanol kulit buah sirsak (Annona muricata Linn) dan uji aktivitas antioksidan dengan metode DPPH

Phytochemical screening research on the ethanol extract of soursop (Annona muricata Linn) peel and antioxidant activity was tested using the DPPH method. The purpose of this study was to determine several classes of compounds found in soursop rind and to determine the antioxidant activity of ethanol extract of soursop rind against DPPH free radicals. The results showed ethanol extract of positive soursop fruit skin containing flavonoids, tannins, and terpenoids. of soursop fruit skin extract was carried out by DPPH method results obtained IC50 value of 192.13 µg / mL ± 5.198137 which was categorized as weak.