Total Phenolic Assay Research Articles

The potential of white-oyster mushroom (Pleurotus ostreatus) as antimicrobial and natural antioxidant

Abstract. Egra S, Kusuma IW, Arung ET, Kuspradini H. 2018. The potential of white-oyster mushroom (Pleurotus ostreatus) as antimicrobial and natural antioxidant. Biofarmasi J Nat Prod Biochem 16: 17-23. White-oyster mushroom (Pleurotus ostreatus) is a favorite meal in Indonesia. Previously this fungus was known as a useless plant, but after the nutrition is known, everything changes. People tried to cultivate it because the nutrients contents are very good for body health. Therefore, to support this added value in the field of health, especially antimicrobials and antioxidants, this research needs to be done. This research used successive extraction with hexane solvent, acetate ethyl, ethanol, water, and crude ethanol by antimicrobial assay, antioxidants assay (DPPH), total antioxidant content, total phenolic content. The highest results on barrier antimicrobial test which occurred against Candida albicans bacteria was 47.60 % with 100 ppm concentration. While, on antimicrobial assay using Propionibacterium acnes bacteria, there was no significant inhibition. Regarding the antioxidant test against DPPH, the result showed the occurrence of free radical by 25 % on water extraction at the concentration of 100 ppm. Continuously, the total antioxidant content assay showed the ethyl acetate had the highest value of 368.708 mg gae/g. The results of the total content phenolic assay showed the solvent hexane had the value of 78.495 mg gae/g. These findings indicated that mushroom has an active phenolic compound with no contribution to impede its working on Candida albicans assay.

Comparative Evaluation of Antioxidant Potential in Thermally Processed, Underutilized Food Grains of the Himalayan Region

Aims: To determine the bioactive components and total antioxidant capacity (TAC) in selected underutilized crops of the Himalayan region viz. Barnyard millet, Grain amaranth, Rice bean, Black soybean and Horsegram.
 Study Design: Experimental design (Lab experiment).
 Place and Duration of Study: Department of Foods and Nutrition, College of Home Science, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, in the year 2016-18.
 Methodology: We applied different processing techniques (covered pan cooking and pressure cooking) in the underutilized crops and analyzed the total phenol, total flavonoids and total antioxidant capacity (Ferric reducing antioxidant power (FRAP) assay and (2, 2-Diphenyl-1-picrylhydrazyl) (DPPH) by using standard methods.
 Results: It was found that black soybean had highest phenolic content after both thermal treatments (3233.76 mg GAE/100 g for pan cooked and 1883.11 mg GAE/100 g for pressure cooked samples) and TAC by both FRAP (6423.76 mg TE/100 g for pan-cooked and 4415.58 mg TE/100 g for pressure cooked) and DPPH (536.41 and 453.98 mg TE/100g for pan and pressure cooked samples, respectively) method. Among raw samples, rice bean contained the highest flavonoid content and TAC by FRAP assay. In contrast, raw grain Amaranth showed the lowest phenolic content. Further, pressure cooking was found to be better for barnyard millet, while in pulses, pan cooking yielded the best results (in terms of increased value/lower losses).
 Conclusion: It can be concluded that among pulses pan cooked black soybean was found to have a good store of bioactive compounds as compared to rice bean and horse gram. The pressure cooking method was found to be suitable for millet like a barnyard.

Characterization and antioxidant assay of yellow frangipani flower (Plumeria alba) extract

Yellow frangipani flowers (Plumeria alba) are plants that commonly found in the tropics, including Indonesia. Frangipani utilization has not optimum and research about it has not many conducted. This study aims to characterize and test the antioxidant activity of frangipani flower extract. The extraction conducted by maceration method using n-hexane, ethyl acetate, and methanol as solvents. Characterization includes phytochemicals assay (alkaloids, flavonoids, terpenoids, phenolic hydroquinone, tannin-polyphenols, and saponins), total phenolic assay, and total flavonoid assay. Antioxidant test using DPPH radical scavenging assay. The results of the characterization showed that frangipani flower extract positively contained alkaloid, flavonoids, tannins compounds in all solvent phases. Terpenoids are positive in n-hexane and ethyl acetate extract, while saponins are positive in methanol extract. The total phenolic content of n-hexane, ethyl acetate, and methanol extract were 3.6 mgGAE/g; 27.74 mgGAE/g; and 35.23 mgGAE/g. The total flavonoid content of n-hexane, ethyl acetate, and methanol extract were respectively 0.8 mgQE/g; 12.18 mgQE/g; 19.9 mgQE/g. The strongest antioxidant activity is possessed by ethyl extract, followed by methanol extract, and the last are n-hexane extract. Keywords: Antioxidant; frangipani flower; phytochemical; total phenolic; total flavonoid

Antioxidant activities of tea prepared from kenaf (Hibiscus cannabinus L. KR9) leaves at different maturity stages

Kenaf (Hibiscus cannabinus L.) is a fast-growing herbaceous plant that received great attention in Malaysia as a valuable fibre crop. Yet, different maturity of plants’ leaves could affect the antioxidant capacities of the tea prepared. Therefore, the aim of this study was to determine the physical properties of KR9 kenaf leaves and antioxidant activities of tea prepared from KR9 kenaf leaves at four different maturity stages, which were 60, 90, 120 and 150 days after sowing (DAS). The analysis that carried out were DPPH (2-2-diphenyl-1-picrylhydrazyl) radical scavenging assay, ABTS (3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging assay, ferric reducing antioxidant power assay, total phenolic content assay, total flavonoid content assay, and chromatographic analysis of phenolic compounds. Results demonstrated that the kenaf leaves at 150 DAS were able to retain the most colour after drying. It also revealed that the tea prepared from kenaf leaves at 120 DAS showed the highest antioxidant activity in all antioxidant analysis tested. Kenaf leaves tea contained mainly kaempferol, tannic acid, chlorogenic acid, caffeic acid and catechin hydrate. Hence, it was deduced that the antioxidant activity in kenaf leaves increased until 120 DAS and dropped at 150 DAS. There was a strong positive correlation relationship among all the antioxidant analysis and the phenolic compounds presented in the kenaf leaves tea. Thus, the phenolic compounds detected contributed significantly to the antioxidant activities of the kenaf leaves tea. The 120 DAS kenaf leaves was recommended for tea preparation since it possessed high antioxidant activities.

Physico-Chemical Parameters, Phenolic Profile, In Vitro Antioxidant Activity and Volatile Compounds of Ladastacho (Lavandula stoechas) from the Region of Saidona.

The aim of the present study was to characterize Lavandula stoechas (Ladastacho) from the region of Saidona by means of physico-chemical parameters, phenolic profile, in vitro antioxidant activity and volatile compounds. Physico-chemical parameters (pH, acidity, salinity, total dissolved solids, electrical conductivity and liquid resistivity) were determined using conventional methods. The phenolic profile was determined using high-performance liquid chromatography electrospray ionization mass spectrometry (HPLC/ESI-MS), whereas a quantitative determination was also accomplished using the total phenolics assay. In vitro antioxidant activity was determined using the 2,2-diphenyl-1-picryl-hydrazyl assay. Finally, volatile compounds were determined using headspace solid phase microextraction coupled to gas chromatography mass spectrometry (HS-SPME/GC-MS). The results showed that Lavandula stoechas aqueous extract had a slightly acidic pH, low salinity content and considerable electrochemical properties (electrical conductivity and liquid resistivity along with electric potential). In addition, aqueous fractions showed a significantly (p < 0.05) higher phenolic content and in vitro antioxidant activity, whereas phenolic compounds, such as caffeic acid, quercetin-O-glucoside, lutelin-O-glucuronide and rosmarinic acid, were identified. Finally, numerous volatile compounds were found to dominate the volatile pattern of this flowering plant, producing a strong, penetrating, cool and menthol-like odour.

In Vitro Antioxidant and Antimicrobial Properties of Flower, Leaf, and Stem Extracts of Korean Mint.

Traditionally, Agastache rugosa (Korean mint) has been widely used to treat various infectious diseases. The aims of this study were to: (i) determine the phenylpropanoid content of the plant using high-performance liquid chromatography; (ii) undertake total anthocyanin, flavonoid, and phenolic assays; (iii) and evaluate the antioxidant and antibacterial properties of the methanol extracts from the stem, leaves, and flowers of Korean mint. The total anthocyanin, flavonoid, and phenolic content assays showed that the flowers had higher phenolic levels than the stem and leaves. The reducing power, the 2,2-diphenyl-1-picrylhydrazyl superoxide radical scavenging abilities, and the hydrogen peroxide radical scavenging activities were also evaluated so that the antioxidant activities of the extracts from the different plant parts could be evaluated. The flower extracts revealed higher antioxidant properties than the other parts. The antibacterial properties of the methanol extracts from A. rugosa were analyzed by the disc diffusion method, and the flower extracts had higher antibacterial activities against the six bacterial strains used in the study than the other parts. This study provides information on the synergistic antioxidant and antibacterial properties of phenolics derived from the different parts of Korean mint.

Effect of walnut kernel septum membranes hydroalcoholic extract on the shelf life of traditional butter

Incorporation of natural ingredients antioxidants in edible fats can profitably affect their oxidative stability during production and storage. The purposes of the current work were to assess the antioxidant and antimicrobial effect of walnut kernel septum membranes hydroalcohol extract (WHE) in traditional butter (TB). Antioxidant characterization of the extract was screened through methods of DPPH, reducing power and total phenolic assays. After preparation of traditional butter from yogurt, WHE was incorporated into TB at three different concentrations; 0.05%, 0.1% and 0.5% and compared with a control, BHT and tocopherol treated samples (200 mg of BHT and tocopherol/kg). Microbiological studies (Staphylococcus aureus, Coliforms, Psychrotrophic bacteria, yeasts and molds) were done during 90 days of storage time. Changes in Anisidine value (AV), acid value, peroxide value (PV) free fatty acids (FFA), Schaal and Totox value were monitored at 45-day intervals. Sensory evaluation was done using 10 semi-trained panelists based on the 5-point hedonic scale.It was found that the total phenolic content of WHE was 368.86 mg GAE/g. The BHT had higher antioxidant activity than WHE inhibiting 92.3% of the DPPH radical at 600 μg/mL. Peroxide value of TB treated with tocopherol, BHT and WHE 0.5% was 0.29 ± 0.07, 0.39 ± 0.07 and 0.52 ± 0.04 respectively. Furthermore, the WHE incorporated butter has shown low levels of free fatty acids, Schaal and Totox value when compared to control treatment. The WHE 0.5% incorporated sample had the most antimicrobial activity and it inhibited the growth of all the microorganisms (except Staphylococcus aureus) used in the study. Among the treated TB, the samples treated with the control and WHE 0.05% had the highest sensory attributes score. The study showed that WHE could be an excellent natural origin of antimicrobial and antioxidant agents which can be used in butter.

Phenolic profile and antioxidant activity of Jasonia glutinosa herbal tea. Influence of simulated gastrointestinal in vitro digestion

In order to value J. glutinosa DC (rock tea), we characterised its phenolic profile and antioxidant activity. The study was performed in aqueous extracts before and after a simulated in vitro digestion to obtain data regarding phenolics bioavailability. Methanolic extracts were also analysed for comparison purposes. Phytochemical profiles were determined by high-performance liquid chromatography with mass spectrometric detection, whereas total phenolic content (TPC) and antioxidant assays were performed by conventional spectrophotometric methods. The most abundant compounds were dicaffeoylquinic acids, representing more than 90% of phenolics in tea infusions. Statistically significant differences were observed for all parameters except for TPC in methanol and aqueous extracts. Both phenolics amount and antioxidant activities were lower after the in vitro digestion of the infusions. However, although phenolics were lost during the simulated digestion, rock tea is still a good source of bioactive compounds with potential applications in the pharmaceutical or nutraceutical industries.

The Optimization of Pudding Formulation Using Noni (Morinda citrifolia L.) Seen from Antioxidant Content and Sensory Characteristics

Noni (Morinda citrifolia L.) is a fruit that known to be effective against many diseases. Its phenol and flavonoid contentacted as antioxidant, anticancer, antiinflamation and to fluent the blood vessel. Because of its content that rich in antioxidant, this research aim to utilized it as a food product. Pudding is one of food product that categorized as a dessert, which in the production does not require heat treatment, so the antioxidant can be maintained. The purpose of this experiment is to find the optimum formulation of Noni pudding seen from antioxidant content and sensory characteristics. The method of this research is total phenolic assay, total flavonoid assay and sensory evaluation from 50 random panelis age between 18-25 years old. The result showed that Noni fruit has total phenolic 0,13423 mg GAE/ml and the total flavonoid 0,11819 mg GAE/mL. The best formulation of pudding resulted from sensory evaluation was found with the addition 10% concentration of Noni extract 10%.

A paper-based device for simultaneous determination of antioxidant activity and total phenolic content in food samples

We report the first use of a paper-based device as a simple, low-cost and rapid detection platform for simultaneous determination of antioxidant activity and total phenolic content in food samples. Two antioxidant activity assays including 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonate) radical cation (ABTS) assay and cupric reducing antioxidant capacity (CUPRAC) assay and one total phenolic content assay, Folin Ciocaltue reagent (FC) assay were simultaneously employed as a proof-of-concept. The device composed of a central sample zone connected to four pretreatment zones and consecutive detection zones to accommodate all three assays and a sample blank measurement. The analysis was achieved by dropping the samples onto the sample zone to flow to the pretreatment and detection zones containing the stored reagents for each antioxidant assay making the color change that was measured using imageJ software. Assay optimization including key reagent concentrations, reaction time, and surface modification were carried out to obtain sensitive and wide linear rage analyses. Various antioxidant standards were then evaluated to determine the analytical features of the method. The paper-based assays were successfully applied to detect antioxidant activity and total phenolic content in 10 beverage samples with similar gallic acid equivalent (GAE) values to those obtained from traditional assays at a 95% confidence interval. Moreover, the GAE values of the samples obtained from three assay analyses were well correlated to each other with relatively high Pearson's correlation coefficients. These results indicated that the assays gave accurate results and are suitable for simultaneous analysis of antioxidant activity and total phenolic content in real samples.

Phenolic compounds, carotenoids, and antioxidant capacities of a thermo-tolerant Scenedesmus sp. (Chlorophyta) extracted with different solvents

The human body can fight against the adverse effects of chronic exposure to environmental pollutants and stress by consumption of a diet rich in antioxidants. Although fruits and vegetables are the predominant sources, alternative sources of antioxidants such as microalgae are also being explored. Here, we investigate the antioxidant capacity, total phenolic, flavonoid, and carotenoid contents of novel thermo-resistant green microalga Scenedesmus sp. ME02. This strain has previously been shown to have a high polyunsaturated fatty acid content. Four different solvents were used for extraction and the antioxidant capacity was determined to be 3.71 ± 0.11 and 47.01 ± 3.14 μmol Trolox eq. g−1 DW in ethanol/water mixture by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays, respectively. Total phenolic, flavonoid, and carotenoid contents in ethanol/water were measured as 5.40 ± 0.28 mg gallic acid eq. g−1 DW, 1.61 ± 0.76 mg quercetin eq. g−1 DW, 0.61 ± 0.05 mg g−1, respectively. This is one of the few studies that reports the presence and quantification of total flavonoids in microalgae. The correlation between the total phenolic content and FRAP assay, but not the DPPH assay, was statistically significant. Finally, 12 different phenolic compounds were analyzed by reverse-phase HPLC and ethyl acetate extract showed substantial amounts of quercetin (0.84 ± 0.12 mg g−1 DW) and rutin (0.11 ± 0.08 mg g−1 DW). Quercetin amount was also high in the ethanol/water extract along with gallic acid, 4-hydroxy benzoic acid, and chlorogenic acid. To the best of our knowledge, this is the first study that reports significant amounts of quercetin and rutin in a microalgal species.

Study the Antioxidant Activity of Sage (Salvia Officinalis) Leaves Extract

This study was carried out to evaluate two type of sage (salvia officinalis) leaves extracts (Ethanolic and Water extracts) by using two methods (reducing power and chelating ability). So this study shows the high content of phenolic compound of ethanolic and water extract of sage (15.8 and 14.6) % respectively. The leaves of sag were locally obtained, twenty gram of ground material was extracted by 250 ml ethanol 95% or distilled water at boiling point, under reflux for one hr. The extractive was filtered and evaporated at 50 C° to the compete dryness. Total phenol assay, total flavonoid assay, reducing power assay, and chelating ability assay were observed in this study. Results revealed that the ethanoic extract had highest percentage of reducing power than water extract of sage leaves as so as the chelating ability percentage.

Ethnobotanical, Phytochemical, and Biological Study of Tamarix aphylla and Aerva javanica Medicinal Plants Growing in the Asir Region, Saudi Arabia

In this study, Tamarix aphylla and Aerva javanica, plants used in folkloric medicine in the Asir region of Saudi Arabia were studied ethnobotanically, chemically, and biologically to assess their medicinal uses, phytochemical constituents, and biological activities. Ethnobotanical data were collected using semistructured interviews and the use values were calculated. A total of 61 informants were interviewed and results indicated high-value uses (0.9 and 0.7) for the plants. Phytochemical investigation indicated that the plants contained most of the phytochemicals that were tested for. The antioxidant activity was examined by assaying total phenolic content, 1,1-Diphenyl-2-picrylhydrazyl (DPPH), and hydrogen peroxide (H2O2) radical scavenging activity. .The bark extract of T. aphylla showed the best antioxidant effect in total phenolic content, DPPH, and H2O2 assays (278.02 ± 0.16 mg GAE/100 g; The half-maximal inhibitory concentration (IC50): DPPH, 18.39 ± 0.62 μg/mL; H2O2, 252.94 ± 1.86 μg/mL), followed by extract of the A. javanica aerial parts (228.60 ± 2.09 mg GAE/100 g; IC50: DPPH, 28.54 ± 0.53 μg/mL; H2O2, 154.17 ± 0.78 μg/mL) compared with ascorbic acid (DPPH: 27.27 ± 0.11 μg/mL; H2O2: 164.9 ± 0.37 μg/mL). The disc diffusion method performed for antimicrobial activity revealed weak activities in T. aphylla and A. javanica extracts (100 μg/mL) against six human pathogens. It was concluded that these plants possess therapeutic potential in the treatment of 18 types of ailments, which are important phytochemical constituents and antioxidant activities that justify their therapeutic uses in traditional medicine. Thus, this study laid sufficient background for further pharmacological research on extracts of these plants.

Polygonum minus ethanolic extracts attenuate cisplatin–induced oxidative stress in the cerebral cortex of rats via its antioxidant properties

Objective: To explore the protective effect of Polygonum minus ethanolic extract on cisplatin-induced neurotoxicity. Methods: In vitro test, total phenolic content assay and DPPH assay were performed to determine the antioxidant activity of Polygonum minus. For in vivo test, 30 male Sprague- Dawley rats were randomly divided into 5 groups: the control group, cisplatin 10 mg/kg, Polygonum minus 100 mg/kg, Polygonum minus 200 mg/kg and Polygonum minus 400 mg/kg. The control group and the cisplatin group were given distilled water whereas Polygonum minus groups received the respective dose of Polygonum minus extract orally for 14 d. On day 15, a single intraperitoneal administration of normal saline was given to the control group; while 10 mg/kg of cisplatin was given to the cisplatin group and Polygonum minus groups. Body weight, signs of illness, daily activity and mortality were observed at least once daily throughout the experimental period. On day 18, the anterior part of the brain was collected and processed for histological and ultrastructural analyses (right hemisphere). The remaining part (left hemisphere) of the brain was assayed to determine malondialdehyde and catalase levels for oxidative stress analyses. Results: Polygonum minus ethanolic extract possessed high phenolic content (977.6 mg GAE/g) and 95.9% DPPH radical scavenging activities. No mortality was observed in all groups. Rats in the cisplatin group were weak and less active compared to Polygonum minus treated rats. In the cisplatin group, disorganised cellular layers of the cerebral cortex were observed whereas rats treated with low and mid doses of Polygonum minus extract had normal cerebral cortex as in the control group. Mild ultrastructural changes were observed in rats treated with low and mid doses of Polygonum minus extract. Meanwhile, low and mid doses of Polygonum minus extract significantly reduced malondialdehyde level whereas low and mid doses of Polygonum minus extracts groups significantly increased catalase activity compared to the cisplatin group. Conclusions: Polygonum minus ethanolic extract at 100 and 200 mg/kg attenuates cisplatin-induced oxidative stress in the cerebral cortex via its antioxidant activity.

Anti-inflammatory property and gas chromatography-mass spectrometry analysis of ethyl acetate fraction of Crateva adansonii DC leaves

Aims: This study was designed to determine the most active anti-inflammatory fraction of C. adansonii leaves and characterize the bioactive compounds. Methods: Dried and pulverized C. adansonii leaves (CAL) were extracted with 70% methanol, followed by successive solvent partitioning into hexane (CALH), ethyl acetate (CALE), butanol (CALB) and aqueous (CALA) leaf fractions. In vitro antioxidant assays carried out on the extract/fractions were DPPH, hydrogen peroxide, ferric reducing antioxidant power (FRAP), nitric oxide scavenging, total antioxidant capacity (TAC), total phenol (TP) and flavonoid (TF) assays. In vitro anti-inflammatory assays investigated were heat-induced bovine serum albumin (BSA) denaturation and human red blood cell (HRBC) membrane stabilization against hypotonicity- induced hemolysis. Formaldehyde-induced inflammation model in rats was carried out, followed by paw edema measurement as well as serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities assays. The ethyl acetate (CALE) fraction was subjected to GC-MS analytical method. Results: CAL extract and fractions substantially inhibited BSA denaturation and stabilized HRBC membrane against hypotonicity-induced hemolysis, however CALE exhibited the highest activity. CALE also suppressed formaldehyde-induced rat paw edema and significantly (p

Apoptosis-Mediated Cytotoxic Effect of Caralluma adscendens var. attenuata on Colon (HT29) and Hepatic (HepG2) Cancer Cell Lines.

Introduction:Caralluma adscendens var. attenuata (Wight) Grav. and Mayur., a member of Apocynaceae, is a perennial stem succulent plant with wide distribution in tropics and subtropics of the world. This plant is reported for the presence of steroids, flavonoids, saponins, triterpenes, and pregnane glycosides, and is known to have antidiabetic and antiulcerogenic properties.Materials and Methods:In this study, an attempt was made to identify antioxidant capacity and cytotoxic potential of n-hexane and aqueous methanolic extracts of total stem part of C. adscendens var. attenuata. Antioxidant activity was evaluated by total phenolic content assay, total flavonoid content assay, free radical scavenging activity, and reducing ability methods. Cytotoxic activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay and nuclear staining methods for colorectal cancer cell lines HT29 and liver cancer cell lines HepG2.Results:MTT assay method has proven that the IC50 value was 10 μg/mL for both extracts, whereas for cisplatin standard, it was 2 μg/mL. By nuclear staining, the apoptotic cells were identified as oval masses with dark cytoplasm and dense green nuclear chromatin fragments indicating the programmed cell death for both n-hexane and aqueous methanolic extracts at the same concentration (10μg/mL).Conclusion:However, aqueous methanolic extract showed prominent cytotoxic potential against both cancer cell lines.

ANTIOXIDANT CAPACITY AND ANTIMICROBIAL ACTIVITY OF PAEONIA PEREGRINA L. [USAK-ITECIK TULIP] EXTRACTS AND ITS PHENOLIC AND FLAVONOID COMPOUNDS

Introduction: The objective of this study is to investigate the chemical characteristics of Paeonia - Itecik tulip and to evaluate the antioxidant and antimicrobial activities of an extract obtained from its petals and leaves. Materials and Methods: Itecik tulip is native to Usak region and its extracts were prepared to determine the antioxidant activity by using total flavonoid content analysis and phenolic content assay methods. Results: It was detected that radical scavenging activity was higher in the petals than in the leaves, total phenolic content was 23.75 mg GAE/gr in the extract taken from the petals and flavonoid content was higher in the leaves than in the petals. Furthermore, in terms of antimicrobial activity, it was found that it was approximately 3 times more effective against K. Pneumoniae compared to Erythromycin and 2.5 times more effective compared to Penicillin and Vancomycin. Conclusions: It can be concluded that our study subject Itecik tulip leaves may be effective in terms of antioxidant activity and radical scavenging activity It may be useful to compare Paeonia petals with more antibiotics to assess its efficacy. In our research, we would like to emphasize that we will have played a role especially in the recognition of itecik tulip.

Antioxidant Activity of Stem Bark Ethanolic Extracts of Calophyllum pulcherrimum, C. soulattri, and C. teysmannii

The decreased air quality due to severe pollution causes the formation of free radicals in the body. Antioxidants counteract free radicals compounds and are beneficial to health. Calophyllum plants is one of the natural antioxidants source. The study was aimed to determine the best antioxidant activity of ethanolic extracts of stem bark both single and combinations of three species of Calophyllum . The study was conducted from September to December 2017 at the Natural Product Chemistry Laboratory, Research Center for Biotechnology LIPI, Cibinong, West Java. The experiment consisted of seven treatments, repeated three times. The treatments consisted of ethanolic stem bark extracts of a) C. pulcherrimum b) C. soulattri (CS), c) C. teysmannii (CT), d) combination of C. pulcherrimum and C. soulattri (CP+CS), e) combination of C. pulcherrimum and C. teysmannii (CP+CT), f) combination of C. soulattri and C. teysmannii (CS+CT), and g) combination of C. pulcherrimum , C. soulattri and C. teysmannii (CP+CS+CT) with the ratio of mixed extract was 1 : 1 for treatments with two combinations and 1 : 1 : 1 for three combinations. The antioxidant activity was evaluated using DPPH free radical scavenging methods. The total phenolic and flavonoids content assays were conducted base on the reaction of follin-ciocalteu and aluminum chloride reagents respectively. The results showed that combination of Calophyllum stem bark ethanolic extracts revealed higher antioxidant activity, total phenol and flavonoid content compared to its sole extract. CP+CS+CT treatment has the lowest IC 50 value at 3.12 mg.l -1 so that it has the potential as a source of natural antioxidants.

Development and characterization of semi-refined carrageenan (SRC) films from Eucheuma cottonii incorporated with glycerol and α-tocopherol for active food packaging application

This works focuses on the development of biodegradable active films packaging using all natural compounds with the aim of contributing sustainable film not only by reducing the plastic waste to environment but also as a potential substitute of synthetic preservative in food. Active film packaging was formulated using semi-refined carrageenan (SRC) biopolymer extracted from Eucheuma cottonii plasticized with glycerol (G) and incorporated with different concentrations of α-tocopherol (Tp) at 0.1, 0.2, 0.3 and 0.4% v/v as natural antioxidants. Opacity, water solubility and mechanical properties of the resultant film were analysed whereas the migration behaviour of antioxidant films into food simulant during 30 days storages were determined using total phenolic content and DPPH assay. The addition of Tp in SRC + G film decreased the tensile strength but increased the value of elongation at break significantly (p<0.05). Opacity and water solubility were improved with increasing concentration of Tp (p<0.05). The highest and prolonged release of antioxidant to food simulant was determined by SRC+G+Tp0.4% through 30 day storage with total phenolic content value of 2 mg GAE/L sample and 88.59% inhibition for DPPH assay. Hence, the new formulation of SRC+G with tocopherol could be an alternative degradable active packaging that might reduce the need of adding antioxidants directly into food products and also prolong the food shelf life.

Antioxidant Capacity of Nettle Leaves During Osmotic Treatment

Osmotic treatment (OT) of nettle leaves was assessed in various osmotic solutions (sugar beet molasses – SBM and ternary aqueous solution – TAS), at temperatures of 20, 35 and 50 °C, under the atmospheric pressure. The influence of the kind of utilized osmotic solution, process temperature and osmotic time on the antioxidant activity (AOC), expressed with the spectrophotometric assays (ABTS, FRAP and DPPH), as well as two direct current polarographic assays, Hydroxo Perhydroxo Mercury (II) complex assay, based on the decrease of anodic current and assay based on the decrease of a cathodic current of Hg (II) reduction. For determination of the total phenolic content Folin-Ciocalteu assay was used. The Relative Antioxidant Capacity Index (RACI), obtained by setting equal weight for every involved assay was applied in order to get an extensive comparison among analyzed samples and between the used assays. Based on these results, after the OT of nettle leaves in TAS, the AOC decreased, while the OT in SBM increased AOC values. The phenolic antioxidant coefficients (PAC), calculated as the ratio between particular AO capacity and TPC, were used to achieve a more comprehensive comparison between analysed samples, as well as applied assays. The results of RACI evaluation revealed that the most favorable osmotic treatment is the one performed for 5h at 35 °C.