Impact of dehydration of purslane on retention of bioactive molecules and antioxidant activity

Natural Food Resource Valorization by Microwave Technology: Purslane Stabilization by Dielectric Heating

The application of microwave-assisted drying is a promising technique due to the features of process sustainability that are usable for responsible productions. It is largely applied for the stabilization of food products, especially in the agro-food sector. In this study, the weed Portulaca oleracea L. (purslane), with its richness in antioxidant components in addition to its recognized pharmacological properties, has been considered due to its potential to be a natural, well-accepted future food. Attention was focused on the role of the heat and mass transfer rates involved in the drying processes on the nutritional profile of the dried products. For this purpose, different drying protocols (convective, microwave irradiation, microwave-vacuum irradiation) were applied to different parts of purslane herb (apical, twigs, entire structures) and chemical characterizations were performed by a GC/MS analysis of the extracts of the dried products. The results show that microwave treatments can assure a better preservation of fatty acids such as SFAs, MUFAs, and PUFAs (which constitute over 90% of the total components in the apical part, 65% in twigs, and 85% in microwave-vacuum-dried entire purslane samples) and phytosterols (their highest preservation was found in microwave-dried twigs) compared with convective treatments. The chemical composition variability as well as treatment times depend on the drying rates (in microwave treatments, the times are on a minute scale and the rates are up to three orders of magnitude greater than convective ones), which in turn depend on the heating transport phenomena. This variability can lead towards products that are diversified by properties that transform a weed into a valorized food source.

Electropolymerization of poly(methylene blue) on flower-like nickel-based MOFs used for ratiometric electrochemical sensing of total polyphenolic content in chrysanthemum tea

A ratiometric electrochemical sensor for caffeic acid (CAE) detection was constructed using a glassy carbon electrode modified with poly(methylene blue) and flower-like nickel-based metal organic frameworks (PMB@Ni-TPA/GCE). The electrochemical behavior of CAE was investigated at the PMB@Ni-TPA/GCE, and was found to follow a two-electron, two-proton electrooxidation process. PMB was used as the internal reference probe, and Ni-TPA can enhance the electrochemical signals of both CAE and PMB. As the CAE concentration increases, the oxidation peak current of CAE is enhanced but that of PMB keeps almost unchanged. The oxidation peak current ratio between CAE and PMB recorded by differential pulse voltammetry changes linearly with CAE concentration over the range of 0.25-15.0 μM, with a detection limit of 0.2 μM. The proposed sensor was successfully employed to evaluate the total polyphenolic content as CAE equivalent in chrysanthemum tea, and the results were comparable with those given by the reference Folin-Ciocalteu spectrophotometry.

Moisture sorption characteristics of ready-to-eat snack food enriched with purslane leaves

Green leafy vegetables are important part of our regular diet that provides us with essential nutrients necessary to support human life and health. Since these are produced in surplus and have limited shelf-life, preservation of vegetables can help to prevent wastage and increase nutrient availability in the diet during off-season. Purslane leaves, rich in micronutrients were dried using tray dryer at 60 ± 2 °C for 7 h. and incorporated at 20% level in khakhra. Organoleptic and physico-chemical properties of the product were evaluated. Further, the sorption properties of khakhra, were studied at 27 ± 2 °C over a range of water activity of 0.10-0.92. Several models were chosen to fit sorption behavior, but the Peleg model showed the best fit. The present study in fact provides a platform to understand the rationalities behind the physico-chemical changes in the product, which, in turn, helps in predicting the best suitable packaging material for storage in addition to the stability of the product.

Comparative effects of powder, aqueous and methanolic extracts of purslane (Portulaca oleracea L.) on growth performance, antioxidant status, abdominal fat deposition and plasma lipids in broiler chickens

This study was performed to evaluate the comparative effects of dietary supplementation of dried purslane powder (PP), purslane aqueous extract (PAE) and purslane methanolic extract (PME) on performance, antioxidant status, carcass traits and selected plasma lipid parameters in broiler chickens. In total, 420 1-day-old male broiler chicks were divided into seven treatments for 49 days as follows: control (basal diet), basal diets plus 1500 or 3000 mg/kg of PP (PP1500 and PP3000 respectively), basal diets plus 150 or 300 mg/kg of PAE (PAE150 and PAE300 respectively) and basal diets plus 150 or 300 mg/kg of PME (PME150 and PME300 respectively). During the total period of the experiment (0–49 days of the experiment), birds receiving the PP3000 diet had higher (P < 0.05) bodyweight gain and a lower feed conversion ratio compared with those fed other diets. At 24 and 49 days of the experiment, birds receiving the PP3000 diet showed greater (P < 0.05) plasma and liver activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and lower (P < 0.05) plasma and liver levels of malondialdehyde compared with other dietary treatments. Additionally, at 24 days of the experiment, birds receiving the PP3000 diet had a greater (P < 0.05) liver catalase activity than those receiving other dietary treatments. In addition, groups receiving the PP1500, PAE300 or PME300 diets showed greater (P < 0.05) plasma and liver activities of superoxide dismutase, catalase and glutathione peroxidase, as well as lower (P < 0.05) plasma and liver levels of malondialdehyde compared with the control group. At 24 days of the experiment, birds receiving the PP1500 or PP3000 diets showed greater (P < 0.05) jejunal activities of superoxide dismutase, catalase and glutathione peroxidase than other groups. At 49 days of the experiment, birds receiving the PP3000 diet showed greater (P < 0.05) jejunal activities of superoxide dismutase and glutathione peroxidase compared with the control group. Additionally, at both 24 and 49 days of the experiment, groups receiving the PP3000 diet had lower (P < 0.05) jejunal levels of malondialdehyde compared with the control group. At 49 days of the experiment, birds receiving the PP3000 diet had a lower (P < 0.05) relative weight of abdominal fat compared with those receiving the other dietary treatments. Moreover, groups that consumed the PP1500, PAE300 or PME300 diets showed lower (P < 0.05) relative weights of abdominal fat compared with the control group. Groups fed PP, PAE or PME treatments showed lower (P < 0.05) plasma levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol, and higher (P < 0.05) plasma levels of high-density lipoprotein cholesterol than the control group at 24 and 49 days of the experiment, with the most pronounced effects observed in those receiving the PP3000 treatment. In conclusion, PP showed more beneficial effects than PAE and PME, and 3000 mg/kg was the best inclusion level of PP in broiler chicken diets.

Purslane (Portulaca oleracea) Seed Consumption And Aerobic Training Improves Biomarkers Associated with Atherosclerosis in Women with Type 2 Diabetes (T2D)

The aim of this study was to investigate the responses of atherosclerosis plaque biomarkers to purslane seed consumption and aerobic training in women with T2D. 196 women with T2D were assigned into; (1) placebo (PL), (2) aerobic training+placebo (AT + PL), 3) purslane seeds (PS), aerobic training+purslane seeds (AT + PS). The training program and purslane seeds consumption (2.5 g lunch and 5 g dinner) were carried out for 16 weeks. The components of purslane seed were identified and quantified by GC–MS. Blood samples were withdrawn via venipuncture to examine blood glucose, low-density lipoprotein (LDL), high-density lipoprotein (HDL), cholesterol, triglycerides (TG), creatinine, urea, uric acid, NF-κB, GLP1, GLP1R, TIMP-1, MMP2, MMP9, CRP, CST3, and CTSS expressions. Blood glucose, LDL, cholesterol, TG, creatinine, urea, and uric acid levels in the (P), (AT), and (AT + PS) groups were significantly decreased compared to the pre-experimental levels or the placebo group, while HDL, significantly increased. Furthermore, the protein and mRNA levels of NF-κB, TIMP-1, MMP2 &9, CRP, CST3, and CTSS in the (P), (AT), (AT + PS) significantly decreased compared to pre-experimental or the placebo group, while level of GLP1 and GLP1-R increased drastically. Findings suggest that purslane seed consumption alongside exercising could improve atherosclerosis plaque biomarkers through synergistically mechanisms in T2D.

Voltammetric determination of polyphenolic content as rosmarinic acid equivalent in tea samples using pencil graphite electrodes

The quasi-reversible, diffusion controlled behavior of rosmarinic acid (RA) on a disposable pencil graphite electrode (PGE) was established by cyclic voltammetry. Using the anodic oxidation peak presented by RA on the PGE a differential pulse voltammetric (DPV) method was developed for the quantitative determination of RA. The linear range was 10(-8) - 10(-5) M RA and the detection and quantification limits were 7.93 × 10(-9) M and 2.64 × 10(-8) M RA, respectively. The applicability of the developed method was tested by recovery studies and by the assessment of the total polyphenolic contents (TPCDPV) of green, white and black Turkish teas, which were found to be 40.74, 30.04 and 23.97 mg rosmarinic acid equivalent/g dry tea, respectively. These results were in good agreement with those obtained by the Folin-Ciocalteu method. The developed method is a sensitive and cheap tool for the rapid and precise evaluation of TPCDPV of tea samples.