scholarly journals Synthesis of 9-(4-hydroxyphenyl)-3,4,6,7-tetrahydro-2H-xanthene-1,8(5H,9H)-dione using lime and lemon juice as an acidic catalyst and its antioxidant activity

2021 ◽  
Author(s):  
Rini Retnosari ◽  
Nanda Harisya Puteri ◽  
Sutrisno Sutrisno ◽  
Siti Marfu'ah ◽  
Aman Santoso ◽  
...  
2021 ◽  
Author(s):  
Rini Retnosari ◽  
Anita Lestari ◽  
Siti Marfu’ah ◽  
Aman Santoso ◽  
Dedek Sukarianingsih ◽  
...  

2019 ◽  
Vol 50 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Mohammad Ghiath Naser Aldeen ◽  
Rita Mansour ◽  
Malak AlJoubbeh

Purpose This paper aims to study the effect of cooking and food additives, such as lemon juice and vinegar, on phenols and flavonoids contents and antioxidant activity of purslane. Design/methodology/approach The Folin–Ciocalteu method was used to determine total phenols content (TP), while total flavonoid content (TF) was determined by the aluminum chloride method. Two methods were used for determination of antioxidant activity: DPPH (1, 1-diphenyl-2-picrylhydrazyl) assay to determine radical scavenging activity, and ferric-reducing antioxidant power (FRAP) to measure the reducing power. Findings According to the results, leafs had higher values of TP, TF and antioxidant activity than aerial parts. Both lemon juice and vinegar retracted antioxidant properties of leafs. TP and TF of leaves showed deterioration after treatment with lemon by 58% and 21.8%, respectively, and FRAP and radical scavenging activity decreased by 75.8% and 74.5%, respectively (p < 0.001). Also, TP, TF, FRAP and DPPH radical scavenging activity decreased in leaves by 82.2%, 30.5%, 87.8% and 90.9%, respectively, after treatment of leaves with vinegar. TF increased after cooking in studied parts, where no significant statistical difference was observed in TP and antioxidant activity (DPPH assay and FRAP) of cooked aerial parts. Adding lemon juice after cooking increased antioxidant properties of purslane (p < 0.001). Originality/value Purslane has antioxidant activity because it is rich in polyphenols and flavonoids. Effects of food additives and cooking were studied using different measurements. According to the authors’ knowledge, this is the first work that studied the effect of food additives on antioxidant properties of purslane.


2021 ◽  
Vol 10 (1) ◽  
pp. 178-188
Author(s):  
Su Wen ◽  
Yang Hui ◽  
Wang Chuang

Abstract Nano-selenium was synthesized using lemon juice as a reducing agent. The experiments showed that pH value affected greatly the shape and the size of the prepared nano-selenium. At pH 9, lemon juice could reduce 50 mmol/L of selenite ions to nano-selenium with particle size between 50 and 90 nm, which was spherical and well dispersed. Lemon juice acted as both a reducing agent and a stabilizer in the synthesis of nano-selenium, in which the chemical interaction between biomolecules and the nano-selenium surface was the basis for the stable existence of nano-selenium. The selenite concentration influenced the formation of nano-selenium, and a low selenite concentration was beneficial to obtain small particles. The achieved nano-selenium exhibited a strong antioxidant activity positively related to concentration. The comparative study showed that the antioxidation of nano-selenium is weaker than that of vitamin C but higher than that of lemon juice.


2019 ◽  
Vol 8 (4S2) ◽  
pp. 1003-1006

Zinc oxide nanoparticles find its versatile application in medicine and industry when compared with other metal nanoparticles. The present study focuses on biogenic synthesis of Zinc Oxide nanoparticles (ZnONPs) using lemon juice extract. Lemon juice extracts contains natural alkaloids and flavonoids which acts as reducing agent for the synthesis of nanoparticles. The synthesized zinc oxide nanoparticle is characterized by Scanning Electron Microscopy (SEM) and FTIR. FTIR results showed the presence of functional groups which represents ZnONPs and reducing groups responsible for the reduction. The SEM observation reveals the synthesized ZnONPs are cube shaped. The obtained nanoparticle was further studied for toxicity using zebrafish embryos. Toxicity results suggested that the toxicity is dose dependent. Malformations in the embryos such as yolk sac edema and twisted tail were seen in higher concentrations. The antioxidant activity of the synthesized ZnONPs was carried out using DPPH assay. Results implied that the antioxidant activity was also concentration dependent.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Prakash Raj Pandeya ◽  
Ramakanta Lamichhane ◽  
Kyung-Hee Lee ◽  
Gopal Lamichhane ◽  
Se-Gun Kim ◽  
...  

Background. Currently, obesity and its comorbidities have become a serious threat to human health necessitating urgent development of safe and effective therapy for their management. Materials and Methods. In this research, a novel polyherbal formulation (F2) was prepared by mixing specific proportions of royal jelly and lemon juice with ethanol extracts of Orostachys japonicus, Rhus verniciflua, and Geranium thunbergii. The antioxidant activity was assessed using DPPH and ABTS assay methods. The antiobesity potential of the F2 was assessed in vitro using 3T3-L1 fibroblast and in vivo using a high-fat diet (HFD) fed C57BL/6J mice model. F2 was administered in mice at the dose of 23 mg/kg and 46 mg/kg, twice daily by oral gavage. A well-accepted antiobesity agent, Garcinia cambogia (GC), at 200 mg/kg was used as a positive control. Results. F2 was observed to exhibit synergistic antiadipogenic activity in 3T3-L1 cells. This inhibition was reinforced by the downregulation of specific adipogenic transcription factors. Furthermore, F2 was also found to reduce mice body weight gain, food efficiency ratio, fasting blood glucose level, fat deposition into the liver, and mass of white adipose tissue. F2 also played a role in the excretion of fat consumed by the mice. For most of the assays performed, the F2 (46 mg/kg) was comparable to the positive control GC (200 mg/kg). In addition, potential and synergistic antioxidant activity was observed on F2. Conclusion. The results revealed that the formulation F2 exhibited potential antiobesity activity through the inhibition of adipocyte differentiation, dietary fat absorption, and reduction of free fatty acids deposition in tissues.


2017 ◽  
Vol 87 (3-4) ◽  
pp. 191-200 ◽  
Author(s):  
Nidhal Soualeh ◽  
Aliçia Stiévenard ◽  
Elie Baudelaire ◽  
Rachid Soulimani ◽  
Jaouad Bouayed

Abstract. In this study, cytoprotective and antioxidant activities of Rosa canina (RC) and Salix alba (SA), medicinal plants, were studied on mouse primary splenocytes by comparing Controlled Differential Sieving process (CDSp), which is a novel green solvent-free process, versus a conventional technique, employing hydroethanolic extraction (HEE). Thus, preventive antioxidant activity of three plant powders of homogeneous particle sizes, 50–100 µm, 100–180 µm and 180–315 µm, dissolved directly in the cellular buffer, were compared to those of hydroethanolic (HE) extract, at 2 concentrations (250 and 500 µg/mL) in H2O2-treated spleen cells. Overall, compared to HE extract, the superfine powders, i. e., fractions < 180 µm, at the lowest concentration, resulted in greater reactive oxygen species (ROS) elimination, increased glutathione peroxidase (GPx) activity and lower malondialdehyde (MDA) production. Better antioxidant and preventive effects in pre-treated cells were found with the superfine powders for SA (i. e., 50–100 µm and 100–180 µm, both p < 0.001), and with the intermediate powder for RC (i. e., 100–180 µm, p < 0.05) versus HE extract. The activity levels of catalase (CAT) and superoxide dismutase (SOD) in pretreated splenocytes exposed to H2O2, albeit reduced, were near to those in unexposed cells, suggesting that pretreatment with the fine powders has relatively restored the normal levels of antioxidant-related enzymes. These findings supported that CDSp improved the biological activities of plants, avoiding the use of organic solvents and thus it could be a good alternative to conventional extraction techniques.


2021 ◽  
Vol 31 (1) ◽  
pp. 73-79
Author(s):  
Azalia Avila-Nava ◽  
Isabel Medina-Vera ◽  
Pamela Rodríguez-Hernández ◽  
Martha Guevara-Cruz ◽  
Pamela K. Heredia-G Canton ◽  
...  
Keyword(s):  

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
M Merlani ◽  
V Barbakadze ◽  
L Gogilashvili ◽  
L Amiranashvili ◽  
K Mulkijanyan ◽  
...  

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