Lipid Peroxidation Inhibitory Activity Research Articles

Benzyl Isothiocyanate Loaded Gelatin Nanoparticles Display Unique in Vitro Antioxidant Prospects

This present investigation focuses on the fact that nanoformulation of phytochemicals could enhance the therapeutic capacity in different physiological systems by enhancing hydrophilicity and bioavailability. In this study gelatin nano-formulation of benzyl isothiocyanate (BITC) was prepared and characterized by dynamic light scattering and UV-Visible spectrometry. Then antioxidant activity of BITC and BITC-gelatin NPs was determined in different concentrations through measuring 2,2- diphenyl-1- picrylhydrazyl (DPPH), superoxide, hydroxyl radical, nitric oxide scavenging and lipid peroxidation inhibition activities. DLS and UV-Vis study revealed the production of uniform nanosized particles and effective encapsulation of BITC respectively. The results of antioxidant assays suggested that BITC-gelatin NPs more effectively scavenged free radicals and inhibited lipid peroxidation compared to free BITC. The findings proposed that gelatin formulated BITC nanoparticles could be effective against oxidative stress related disorders.

Chemical Analysis and Biological Activities of Various Parts of Securidaca longipedunculata From South Africa

Objective The objective of our study was to investigate the chemical composition and the biological activities of different parts of Securidaca longipedunculata from South Africa. Methodologies The chemical analysis methods, including chromatography and spectroscopy, were employed to identify the diverse array of compounds present in the roots, leaves, and stems of S longipedunculata. Results The proximate analysis revealed that the leaf extracts had higher ( P < .05) crude protein, gross energy, and ether extract contents when compared to the stem bark and the root bark. A similar trend was observed with the mineral analysis where copper, iron, magnesium, and zinc were in abundance in the leaves. Concurrently, bioassays reveal significant biological activities, such as antioxidant, antimicrobial, and anti-inflammatory properties, associated with these plant parts. The extracts demonstrated high lipid peroxidation inhibitory activity at the concentration of 250 μg/mL, with the highest percentage inhibition of 94% recorded in the dark leaf extract, followed by 92% and 73% at the concentrations of 125 and 62.5 μg/mL, respectively. The antimicrobial analysis revealed that the root bark extract was active against Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis with the average minimum inhibitory concentration of 1.67 mg/mL (dark type) and 0.63 mg/mL (light type). Conclusion Our findings emphasize the medicinal potential of S longipedunculata and underscore the importance of understanding its chemical makeup in explaining its therapeutic effects. This research provides valuable insights into the pharmacological properties of S longipedunculata, offering a foundation for further exploration in drug development and natural product discovery.

The Effect of ZnCl2 Concentrations and Heating Methods on the Chlorophyll, Phenolic, Andrographolide Content and Antioxidant Activity of Sambiloto (Andrographis paniculata) Simplicia Powder

The drying process in Sambiloto simplicia production causes the degradation of chlorophyll as the major compound. However, the stability of chlorophyll can be enhanced by forming a metallochlorophyll complex with zinc (Zn) metal. This research aims to produce Zn-rich Sambiloto simplicia powder to produce high stability of chlorophyll. Sambiloto simplicia powder was prepared through sorting, grinding, sieving, and mixing with ZnCl2 solution at concentrations of 0, 200, 300, 400, and 500 ppm, followed by heating (using either oven or an autoclave) and drying. The analysis included determination of total chlorophyll, phenolic, flavonoid, zinc, and andrographolide content. DPPH and FTC assays were employed to evaluate antioxidant activity. The results showed that increasing ZnCl2 concentration up to 300 ppm enhances chlorophyll, phenolic, flavonoid, zinc, and andrographolide content. Higher concentrations of ZnCl2 in the oven resulted in decreased lipid peroxidation inhibition (LPI) of Sambiloto simplicia powder, whereas using an autoclave led to increased LPI. Furthermore, higher ZnCl2 concentrations, up to 400 ppm, corresponded to increased DPPH radical scavenging activity. Lipid peroxidation inhibition activity correlated with andrographolide, zinc, and total phenolic contents. Conversely, DPPH radical scavenging activity strongly correlated with total phenolic, total flavonoid, Zn, chlorophyll, andrographolide content.

Antioxidant potential of Camellia tetracocca and meitan turquoise bud in inhibiting oxidative degradation of edible oils

Effective antioxidants are crucial for preventing lipid deterioration. This study aimed to investigate the antioxidant properties and inhibitory effect on lipid oxidation of Camellia tetracocca (CT) and Meitan Turquoise Bud (MTB) extracts. The research analyzed the total flavonoids, phenolics, and major components content of the extracts. Additionally, it evaluated the in vitro antioxidant ability (FRAP, DPPH, ABTS assays) and lipid peroxidation inhibitory activity, and calculated the binding energy of the major components and fatty acids. Compared to CT, MTB had higher total flavonoid and phenolic content, along with superior antioxidant activity in vitro. Both extracts effectively inhibited the increase of POV in camphor oil and olive oil containing 74.63% and 69.96% oleic acid, respectively. Interestingly, MTB outperformed CT twelve days earlier, but CT surpassed MTB twelve days later in inhibition rates on these oils. Molecular docking confirmed that the binding energy of the active ingredients in both extracts with oleic acid-type edible oil is higher than that with linoleic and linolenic acid types. These findings indicate that CT and MTB extracts are promising natural antioxidants for oleic acid-rich edible oils. Given their differing impact on the oxidation rate of edible oil, using both extracts together may produce superior outcomes.

Phytochemical compounds and antioxidant capacities of Abelmoschus manihot leaf extracts using different solvents

Abstract. Winata GM, Hardinsyah H, Marliyati SA, Rimbawan R, Andrianto D. 2024. Phytochemical compounds and antioxidant capacities of Abelmoschus manihot leaf extracts using different solvents. Biodiversitas 25: 942-949. Gedi (Abelmoschus manihot (L.) Medik) leaves are popularly consumed as a green vegetable by Eastern Indonesians. This work aimed to carry out the phytochemical compounds and antioxidant capacities of five extracts, i.e., water, 70% ethanol, absolute ethanol, ethyl acetate, and hexane of Abelmoschus manihot leaf. Qualitative analysis was done as a preliminary screening for flavonoid, tannin, saponin, alkaloid, triterpenoid, steroid, and quinone. Quantitative analysis determined the flavonoid, phenolic, tannin, quercetin, and steroid content. In-vitro antioxidant analysis was conducted to determine free radical scavenging activity and lipid peroxidation inhibitory activity. The results showed that flavonoid was only found in 70% ethanol extract; steroid was obtained in all extracts, while alkaloid, saponin, tannin, quinone, and triterpenoid were absent in all extracts. The results of the quantitative analysis showed that the highest flavonoid was in 70% ethanol extract (39.2 mg GAE/g), phenolic in ethyl acetate extract (34.792 mg QE/g), tannin in 70% ethanol (1.395 mg/g), quercetin in absolute ethanol extract (0.246 mg/g), and steroid content in hexane extract (201.948 mg/g). Half maximal inhibitory concentration (IC50) of each extract to inhibit malondialdehyde (MDA) formation was lower than free radical scavenging activity. The IC50 values of MDA formation in absolute ethanol and hexane extracts were 6.77 ppm and 7.67 ppm, respectively. The IC50 of vitamin E was 3.67 ppm. Further study is needed to determine the mechanism of Abelmoschus manihot leaf extracts as antioxidants used as a functional food.

Emulsifying and Lipid Peroxidation Inhibitory Activities of Chicken Head Protein Hydrolysate Using a Combination of Papain and Bromelain Enzymes

Protein hydrolysis is a method used to produce protein hydrolysates containing simple peptides and free amino acids. The chicken head is one of the by-products that contain a high protein concentration so it can be use as a raw material for protein hydrolysate with functional properties and as a lipid peroxidation inhibitor. The aim of this research was determination to determine the emulsifying and lipid peroxidation inhibitory properties in chicken head protein hydrolysate using a combination of papain and bromelain enzymes. The method used in this research was a laboratory experiment using a completely randomized design (CRD) consisting of 4 treatments and 5 replications, consisting of T1 (without hydrolysis), T2 (75% papain enzyme and 25% bromelain enzyme), T3 (papain enzyme 50% and bromelain enzyme 50%), and T4 (papain enzyme 25% and bromelain enzyme 75%). The difference in the concentration ratio of papain enzyme and bromelain enzyme in chicken head protein hydrolysate gave a very significant difference (P<0.01) in Electrical conductivity (EC), a significant difference (P<0,05) in lipid peroxidation inhibitory activity and emulsion activity, and no significant difference (P>0,05) in emulsion stability. Chicken head protein hydrolysate shows potential as an emulsifier and lipid peroxidation inhibitor.

Enhancing the Antioxidant Potential of Weissella confusa PP29 Probiotic Media through Incorporation of Hibiscus sabdariffa L. Anthocyanin Extract.

Lactic acid bacteria (LAB) produce important metabolites during fermentation processes, such as exopolysaccharides (EPS), which represent powerful natural antioxidants. On the other hand, H. sabdariffa L. anthocyanin extracts protect LAB and support their development. This study uncovers for the first time, the antioxidant profile of Weissella confusa PP29 probiotic media and focuses on elevating its impressive antioxidant attributes by synergistically integrating H. sabdariffa L. anthocyanin extract. The multifaceted potential of this innovative approach is explored and the results are remarkable, allowing us to understand the protective capacity of the fermented product on the intestinal mucosa. The total phenolic content was much lower at the end of the fermentation process compared to the initial amount, confirming their LAB processing. The DPPH radical scavenging and FRAP of the fermented products were higher compared to ascorbic acid and antioxidant extracts, while superoxide anion radical scavenging and lipid peroxidation inhibitory activity were comparable to that of ascorbic acid. The antioxidant properties of the fermented products were correlated with the initial inoculum and anthocyanin concentrations. All these properties were preserved for 6 months, demonstrating the promising efficacy of this enriched medium, underlining its potential as a complex functional food with enhanced health benefits.

Comparison of some biological activities of propolis and bee bread samples obtained from Apis mellifera Anatoliaca and its Muğla and Efe ecotypes

Honey and other bee products have been extensively researched in recent years due to the demand for natural products with nutritional and therapeutic qualities, as they contain high levels of biologically active compounds and valuable nutrients. In this study, antioxidant, anti-inflammatory and antimicrobial activities of bee bread and propolis samples formed after colony development by bees of different races and ecotypes accepted to core colonies in the same location were evaluated. Total phenolic, flavonoid and antioxidant content values were the the highest in propolis samples, especially in propolis from Apis mellifera anatoliaca. Values of this type gave the most effective results in almost all of the other tests performed, such as DPPH free radical scavenging, lipid peroxidation inhibition, anti-inflammatory and antimicrobial activity. In addition, the amount of phenolics detected in the phenolic component analysis of this species is higher. It was surprising that propolis samples obtained from Efe and Muğla ecotypes showed higher values, respectively, in the test for chelating activity with Fe. The fact that the values calculated for the bee breads were lower in all cases compared to the propolis samples, the highest values were calculated for the bee bread harvested from the efe ecotype, in contrast to the propolis ecotypes. None of the tested bee breads showed antimicrobial activity on selected pathogenic bacteria. Thus, with this study, it was evaluated how the differences arising from both race and ecotype and the type of bee product reflected on biological activities.

Determination of antioxidant and anti-inflammatory properties of Salvia aethiopis/sclarea and synthesized silver nanoparticles

Aim: In the study, the phenolic compounds of Salvia aethiopis/sclarea will be determined and the antioxidant and anti-inflammatory activities of the extracts of these plants and the synthesized silver nanoparticles (AgNP) will be examined in vitro. Materials and Methods: Extracts obtained from Salvia spp. (SE) collected from the Kyrenia region of Cyprus were used in the study. Methanol extracts were prepared and total phenolic, flavonoid and alkaloid contents were determined. The amount of phenolic compounds was then quantified and identified using HPLC. The antioxidant properties of Salvia aethiopis/sclarea were analyzed using various markers, including lipid peroxidation inhibition activity, 1,1-Diphenyl-2-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) scavenging capacity. Additionally, their anti-inflammatory effects were investigated by proteinase inhibitor activity, heat-induced hemolysis and albumin denaturation analyses. Results: S. aethiopis and S. sclarea were contained high levels of the phenolic compounds isoquercetin and caffeic acid or naringenin and caffeic acid, respectively. After green synthesis of silver nanoparticles, the antioxidant and anti-inflammatory properties of plant extracts increased significantly (p<0.05). Conclusion: Our study found that silver nanoparticles synthesized using S. aethiopis/sclarea extract increased the antioxidant and anti-inflammatory effects of plant extracts and suggested that AgNP/SE could be used as a potential therapeutic agent in medicine.

Characterization, antioxidant, and sausage preservation effects of ethanol extract from lotus seed peel powder

The ethanol extract from lotus seed peel powder (EEL) were characterized, and its antioxidant and sausage preservation effects were investigated in this study. Chemical composition, UV and FTIR spectra of EEL, 70% ethanol-soluble matter (70-DF), and precipitate (70-PF) showed similar trends to some extent, indicating their similar chemical composition. Then, their antioxidant potentials were confirmed that EEL exhibited stronger DPPH· scavenging capacity, FRAP, and lipid peroxidation inhibitory activities than those of 70-DF and 70-PF. Correlation analysis also indicated phenolics as the main antioxidant components of EEL. Hence, catechin, epicatechin, rutin, phlorizin, and gallic acid were identified as the dominant phenolics of EEL. Throughout the chopping, roasting, cooking and pasteurization processes, EEL could protect the color, maintain the pH value, and decline the total volatile base nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARS) values of sausages. Following 18 days of storage at 25 °C, supplementation with EEL reduced the TVB-N and TBARS values of sausages, while pH value showed an opposite trend. The present study found that EEL could prolong the shelf life of sausages via inhibiting the oxidation of lipids and proteins, which would promote the utilization of lotus seed peel powder as a substitute for nitrites to preserve meat products.

Antioxidant, Antistress, Nootropic activity and its Correlation studies of aqueous extract of Punica granatum fruit estimated by Noninvasive biomarkers and Y-maze test in rodents

The memory loss associated with increased oxidative stress due to increased level of free radicals. Oxidative stress has been involved in several diseases includes cancer, atherosclerosis and neurodegenerative diseases.This study aimed to estimate the correlation of antioxidant and antistress activity with nootropic activity of aqueous extract of pomegranate (Punica granatum) by in-vivo noninvasive studies using rats. The in-vitro antioxidant activity was determined based on the ability of the Punica granatum to scavenge free radicals and lipid peroxidation inhibiting activity. The antistress effect of the aqueous extract of Punica granatum for 24h treatment (100 and 300mg/kg, p.o.) was evaluated by using the forced swim stress test in rats. The 24h urinary excretion of vanillylmandellic acid (VMA), 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and ascorbic acid (AA) was determined in all groups under normal and stressed conditions by HPLC and spectrophotometric methods in all groups, were selected as noninvasive biomarkers. Nootropic activity activities of Punica granatum fruit extract were estimated as locomotor and working memory in rats in a Y-maze apparatus. Administration of aqueous extract of Punica granatum at a dose of 100 and 300mg/kg reduced the urinary metabolite levels. Punica granatum treatment showed significant dose dependent variation in non-invasive biomarker levels in urine samples of rats taken after 24h. The treatment with Punica granatum extracts improved the percentage entry of rats into safer zone, it means acquisition (learning) retention and retrieval (memory) were improved in rats compared to stress controls. Cognition determined by working memory and locomotor activity results were shown to be dose-dependent. The results of this study strongly suggestedantioxidant, antistress and nootropic activity effect of Punica granatumin rodents were correlated. The data obtained were analyzed by one-way ANOVA followed bytukey test. p<0.05 was considered to be significant. There is substantial evidence that flavonoids play an active role in providing antioxidant, antistress and nootropic activities of Punica granatum extracts. The findings of the present investigations indicate that the Punica granatum has significant antistress activity, which may be due to the immunostimulating property and increased resistance, nonspecifically, against all experimental stress conditions. The study provided scientific evidence for their utility as nootropic agents and to advocate their use in foods.

Erica arborea Bitkisi Kullanılarak Sentezlenen Çinko Nanopartiküllerin Biyoaktivitesinin Değerlendirilmesi

The synthesis of nanoparticles by environmentally friendly, cost-effective and simple methods has been the subject of much research in medicine and industry. In particular, it offers a promising approach for the development of next-generation nano-based drugs. This study synthesized zinc oxide nanoparticles (ZnO NPs) using Erica arborea (E. arborea) leaf extract as a stabilizing and reducing agent. The prepared ZnO NPs were characterized by UV-vis, FTIR and SEM-EDX analysis. SEM-EDX analysis showed that the nanoparticles were spherical in shape and showed strong signals of zinc metal. UV-vis analysis confirmed that the color of the solution changed to light yellow, indicating the formation of nanoparticles, and exhibited an absorption peak at 350 nm. FT-IR confirmed that the formation of nanoparticles was accompanied by metabolites of the leaf extract. The pharmacological potential of zinc nanoparticles synthesized by E. arborea was evaluated by antioxidant (DPPH method), antimicrobial (disk diffusion method) and lipid peroxidation (TBA method) activities. The biosynthesized ZnO NPs exhibited better antioxidant activity compared to the plant extract. The IC50 values of DPPH radical scavenging activity of ZnO NPs and leaf extract were 18.71±0.35 and 9.21±0.10, respectively. The lipid peroxidation inhibitory activity IC50 value of ZnO NPs was found to be 5.33±0.09. ZnO NPs were found to be sensitive against pathogenic bacteria P. aeruginosa, B. cereus, B. subtilis and S. aureus and fungal strain C. albicans. The findings suggest that synthesizing naturally synthesized zinc nanoparticles could be an alternative agent to physical and chemical methods. In addition, the pharmacological activity of nanoparticles will contribute to next-generation drug development studies.

Identification of bolegrevilol B and C as novel antioxidant compounds in Suillus grevillei mushroom.

Suillus grevillei is a popular species of mushroom available worldwide. In this study, we isolated compounds, bolegrevilol B and bolegrevilol C, from the mushroom and observed their potent lipid peroxidation-inhibiting activity. The structures of bolegrevilol B and bolegrevilol C were elucidated as 3-geranylgeranyl-1,2,4-trihydroxybenzene and 3-geranylgeranyl-1,2-dihydroxy-4-methoxybenzene, respectively, through high-resolution electrospray ionization mass spectrometry (-) and 1D and 2D nuclear magnetic resonance analyses. Bolegrevilol B and C inhibited lipid peroxidation and exhibited IC50 values of 2.0±0.29 µm and 1.0±0.13 µm, respectively. Furthermore, bolegrevilol B and C demonstrated potent neuroprotective activities in neuronal hybridoma N18-RE-105 cells against L-glutamate toxicity (EC50 of 1.8±1.7n m and 7.2±6.9n m, respectively). Bolegrevilol B was found in nature for the first time, and, to the best of our knowledge, this is the first study to report the antioxidant activities of bolegrevilol B and C.

The chemical composition from the fruits of Pandanus tonkinensis, their NO production inhibitory and lipid peroxidation inhibitory activities

AbstractSeven known compounds, including two neolignans, four lignans, and one flavane were isolated from the methanol extract of Pandanus tonkinenis fruits. Their structures were determined to be ficusal (1), vladinol F (2), medioresinol (3), syringaresinol (4), lariciresinol (5), secoisolariciresinol (6), and luteoliflavan (7) by analysis of MS and NMR data as well as by comparison of their spectral data with those reported in the literature. All compounds were evaluated for NO production inhibitory and lipid peroxidative inhibitory activities. Compounds 5 and 7 showed significant NO production inhibitory with IC50 values of 5.3±0.4 and 7.1±0.4 μM, respectively. Compounds 6 and 7 showed significant lipid peroxidative inhibitory activity with IC50 values of 20.2±1.7 and 26.2±3.6 μM, respectively.

Non-Enzymatic and Enzymatic Antioxidant Responses of Hypericum perforatum L. Hairy Roots upon Photooxidative Stress

The aim of this study was to evaluate the non-enzymatic and enzymatic antioxidant response of fifteen Hypericum perforatum L. dark-grown (HR1 A-HR1 O) and photoperiod-exposed (HR2 A-HR2 O) hairy root clones. Dark-grown HR1 clones were characterized with high biomass accumulation and up-regulated phenylpropanoid metabolism through phenylalanine ammonia lyase (PAL)-mediated production of flavonoids, flavan-3-ols and anthocyanins. These groups of phenolics showed superior hydrogen-donating capability and significantly contributed to the antioxidant capacity of dark-grown HR1 clones. Photoperiod-exposed HR2 clones showed green coloration with shoot regenerative potential and reduced biomass accumulation. Photoperiod exposition improved the production of hypericins, as well as ferrous chelating properties and lipid peroxidation inhibition activity in HR2 cultures. Furthermore, HR2 clones were represented with enhanced activity of antioxidant enzymes (guaiacol peroxidase, catalase and superoxide dismutase) that resulted in suppression of oxidative stress markers (hydrogen peroxide, superoxide anion and malondialdehyde). These observations revealed the involvement of an efficient antioxidant defense system in the adaptive response of HR to photooxidative stress. Altogether, photoperiod-exposed H. perforatum HR2 clones were considered as a promising alternative for further scale-up production of naphthodianthrones that could be used in the pharmaceutical industry.

Impact of Spices on Micronutrients, Phenolic Compounds, in Vitro and in Vivo Antioxidant Potentialities in Eggplant Leaves Cooked with Water

Eggplant leaves (<i>Solanum macrocarpon</i>) are rich in nutrients which are unfortunately lost during cooking. To reduce micronutrients losses and enhance antioxidant potentialities, they were cooked in water for 30 minutes with onion, ginger and Guinea pepper. The analyzes focused on the determination of vitamin C, β-carotene, phenolic compounds, free radical-scavenging and lipid peroxidation inhibitory activities. In Wistar rats, thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD) and glutathione peroxidase activities were also evaluated during 1 month. The results indicated that vitamin C remained low in eggplant leaves cooked with onion and spices. Cooked eggplant market leaves β-carotene content (187.11 μg/100 FM) increase from 447.43 μg/100 FM (with onion) to 905.44 μg/100 FM (with Guinea pepper). Ginger, Guinea pepper and onion improved eggplant field leaves free radical scavenging activities, which previous IC₅₀ value (12.00 µg/ml) became 0.67, 0.83 and 3.08 μg/ml respectively. TBARS rate increased only for rats which received eggplant market leaves cooked with onion from 0.02 to 0.03 nmol/ml. SOD activities increased during the firsts 2 weeks of experiment. Glutathione peroxidase activities is high in serum of rats which received eggplant field leaves cooked with onion (18.70 nmol/min/ml). Onion, ginger and Guinea pepper enhance eggplant antioxidant potentialities during cooking.

Evaluation of Semecarpus kurzii Engler from Bay Islands for oxidative DNA damage protective activity and in vitro antioxidant potential

Introduction and Aim: Harnessing traditional knowledge of medicinal plants is important for the betterment of mankind. We must safeguard traditional knowledge from misuse by miscreants living in modern societies and knowledge must be available in the public domain for use in drug designing in the healthcare system. Since the beginning of recorded history, Indians have used plants as a source of medicine, and their cultural past is incredibly rich. This study was conducted to evaluate the oxidative stress-induced DNA damage prevention and antioxidant potential of Semecarpus kurzii found in the Bay Islands. Materials and Methods: The scavenging of superoxide, hydroxyl radicals, nitric oxide (NO), 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) radicals, ferric reducing power (FRAP), and lipid peroxidation inhibition activity were tested to determine antioxidant activity. DNA damage inhibition test was used to evaluate the protection against oxidative DNA damage. Results: The S. kurzii extract showed dose-dependent scavenging of DPPH, superoxide anion, nitric oxide, hydroxyl radical and reducing power evaluated by comparing with standard antioxidants (ascorbic acid, alpha-tocopherol and BHT). However, the nitric oxide scavenging (IC50 =186.47) and superoxide scavenging (IC50 = 678.32) was more than that of DPPH (IC50 =28.03) and Hydroxyl radical (IC50 =89.10) scavenging capacity. In addition, S. kurzii extract and ascorbic acid showed lipid peroxidation inhibition activity. The extract also exhibited DNA protection which was confirmed by the DNA damage inhibition assay. Conclusion: Our results corroborated that, the methanolic extract of S. kurzii bark has substantial antioxidant activity and DNA damage inhibition. The potential antioxidant and oxidative DNA damage preventive activity could be due to the existence of polyphenolic compounds in the S. kurzii bark.

Selection of bioactive chemical markers for anti-aging skin assessment of Dimocarpus longan Lour. leaf extract

Hydroethanolic longan (Dimocarpus longan Lour.) leaf extract has reported remarkable biological activities related to the aging process for use in cosmeceuticals. Finding the bioactive chemical marker (BCM) could play a crucial role for cosmeceutical manufacturers in guaranteeing the quality of the extract and its efficacy. This study aimed to select the most potential BCM established and predicted for the anti-aging skin of hydroethanolic longan leaf extract. The assessment of anti-aging of the skin was determined by evaluating in vitro antioxidant activities, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and inhibiting lipid peroxidation assay. Furthermore, anti-hyaluronidase and anti-collagenase activity were also determined. The extract underwent bioassay-guided fractionation using normal phase preparative-thin layer chromatography. Ethyl gallate in the fractionated extract possessed biological activities as a high proportion part. The strong positive linear relationship between DPPH scavenging, lipid peroxidation inhibition, anti-collagenase, and anti-hyaluronidase activity (r = 0.997, 0.972, 0.998, and 0.998, respectively) under the deterioration of the ethyl gallate was shown. The molecular docking of ethyl gallate to collagenase and hyaluronidase resulted in a good and acceptable binding affinity. Therefore, ethyl gallate could be potentially used as a bioactive chemical marker for hydroethanolic longan leaf extract in pharmaceutical and cosmeceutical applications.

Effects of Local Anesthetics on Liposomal Membranes Determined by Their Inhibitory Activity of Lipid Peroxidation.

In this study, we investigated the effects of drugs on membrane function in which lipid peroxidation was inhibited by the antioxidant Trolox (TRO) in liposomes containing egg yolk lecithin. Local anesthetics (LAs), such as lidocaine (LID) and dibucaine (DIB), were used as model drugs. The effect of LAs on the inhibitory activity of TRO was evaluated by calculating the pI50 from the inhibition constant K calculated by curve fitting. pI50TRO indicates the strength of TRO membrane protective function. pI50LA indicates the strength of LA activity. LAs inhibited lipid peroxidation in a dose-dependent manner and decreased pI50TRO. The effect of DIB on pI50TRO was 1.9 times more than that of LID. This result indicated that LA may improve the fluidity of the membrane, which may facilitate the migration of TRO from the membrane to the liquid phase. As a result, TRO is less likely to suppress lipid peroxidation within the lipid membrane, possibly resulting in a decrease in pI50TRO. The effect of TRO on pI50LA was found to be similar in both, indicating that it did not depend on the type of the model drug. These results suggest that our developed procedure successfully quantified the effects of LAs on lipid membrane functions. We were able to obtain the characteristics of model drugs independent of TRO by simultaneously measuring and analyzing the lipid peroxidation inhibitory activities of TRO and model drugs in liposomes.

Lipid Peroxidation Inhibitory and Cytotoxic Activities of Two Camellia Species Growing Wild in Vietnam

Background Leaves, flowers and young shoots of yellow Camellia species are often used as a substitute for green tea in Vietnam. Yellow Camellia species contain high levels of polyphenol compounds, and have shown activities such as antioxidant, anticancer, and cytotoxic. Objectives We qualitatively screened phytochemicals, quantified total polyphenols of 70% ethanol (EtOH) extracts of leaves, young shoots, and flowers of Camellia vuquangensis and Camellia hatinhensis in Ha Tinh Province, Vietnam. Furthermore, these extracts have been evaluated for lipid peroxidation inhibitory activities at the in vivo level in the BALB/c mouse model, and in vitro cytotoxic activities. Materials and Methods Chemical methods and thin-layer chromatographic (TLC) analysis were used for the qualitative screening of phytochemicals. High-performance liquid chromatography (HPLC) was used to determine total polyphenols. Cell survival was determined through optical density (OD) measured when the protein composition of the cells was stained with sulforhodamine B (SRB). Inhibition of lipid peroxidation was evaluated by determining the content of malondialdehyde (MDA), which is a product of membrane lipid peroxidation. Results The total polyphenol contents of all parts of the two species were comparable to that of green tea with values between 319.3 and 342.6 mg gallic acid equivalents (GAE/g) dry weight. Extracts of leaves, flowers of C. vuquangensis and C. hatinhensis showed strong lipid peroxidation inhibitory activities (IC50: 7.92–17.45 µg/mL) and moderate cytotoxic activities against cell lines HepG2, A549, MCF7, SK-Mel-2, HT-29, and AGS (IC50: 34.73–80.58 µg/mL). Conclusion These two tea species may be considered as herbal teas with various health benefits.