Variations in phenolic composition and antioxidant properties among 15 basil (Ocimum basilicum L.) cultivars

In this study, the influences of cultivar on the phenolic composition and antioxidant properties of 15 different basil varieties was determined. Cultivar had a statistically significant effect on total phenolic levels (p < 0.001) and anthocyanin concentrations (p < 0.001). Analysis of individual phenolic acid levels by high-performance liquid chromatography showed substantial variations in the phenolic acid profiles among cultivars. Rosmarinic (p < 0.001), chicoric (p = 0.002) and caffeic (p = 0.001) acid concentrations were affected by cultivar, although caftaric acid levels (p = 0.083) were not. Nine of the cultivars in this study contained chicoric acid in higher concentrations than rosmarinic acid. These are the first basil cultivars that have been identified in which rosmarinic acid is not the dominant phenolic acid. In addition, six of the cultivars in this study had caftaric and caffeic acid concentrations that were similar or higher than rosmarinic acid levels. Cultivar also had a significant impact on both FRAP (ferric reducing antioxidant power, p = 0.007) and DPPH (2,2′-diphenyl-1-picrylhydrazyl, p = 0.004) antioxidant capacities. For the basil cultivars in this study, the individual phenolic acid composition was found to be an important factor influencing the measured antioxidant capacity.     

Profiling of in vitro neurobiological effects and phenolic acids of selected endemic Salvia species

The ethyl acetate and methanol extracts from 16 Salvia L. species were screened for their inhibitory activity against acetylcholinesterase, butyrylcholinesterase, lipoxygenase, and tyrosinase; the enzymes linked to neurodegeneration. Their antioxidant activity was also tested using DPPH radical scavenging, metal-chelation, and ferric-reducing antioxidant power (FRAP) assays. Total flavonoid content of the extracts was determined by AlCl₃ reagent, while HPLC technique was applied for analysis of various phenolic acids in the extracts. The extracts exerted weak cholinesterase and tyrosinase inhibition, and remarkable inhibition against lipoxygenase (13.07 ± 2.73-74.21 ± 5.61%) at 100 μg ml⁻¹. The methanol extracts showed higher antioxidant activity in DPPH radical scavenging and FRAP assays. The extracts were analyzed for their gallic, protocateuchic, p-hydroxy-benzoic, vanillic, caffeic, chlorogenic, syringic, o- and p-coumaric, ferulic, rosmarinic, and tr-cinnamic acid contents and the methanol extract of Salvia ekimiana (153.50 mg 100 g⁻¹) was revealed to be the richest in terms of rosmarinic acid.     

Antioxidant capacity,total phenolics,glucosinolates and colour parameters of rapeseed cultivars

The antioxidant capacity of twenty nine rapeseed varieties was determined by using ferric reducing antioxidant power (FRAP) and 2,2′-diphenyl-1-picrylhydrazyl (DPPH) methods. Mean FRAP (3190–6326 μmol Trolox/100 g) and DPPH (3194–6346 μmol Trolox/100 g) values for methanolic extracts of rapeseed cultivars did not differ significantly. Moreover, the total content of phenolics (756–1324 mg sinapic acid/100 g), glucosinolates (4.2–87.5 μmol/g, respectively), erucic acid (0.0–56.1%) and colour parameters of the studied rapeseed cultivars were analysed. Antioxidant capacity determined by FRAP and DPPH methods correlated significantly with total phenolic content (TPC) in rapeseed cultivars (r = 0.9332, 0.9339, p < 0.001). Also, significant, inverse correlations were found between antioxidant capacity, total phenolics and luminosity (L^∗) or red colour intensity (a^∗) of rapeseed cultivars. Principal component analysis (PCA) allowed the rapeseed varieties to be differentiated based on their antioxidant capacities, total amounts of phenolics, glucosinolates, erucic acid and colour parameters.     

Determination of total phenolic content and antioxidant capacity of onion (Allium cepa) and shallot (Allium oschaninii) using infrared spectroscopy

Total phenolic content (TPC) and total antioxidant capacity (TAC) of four onion varieties (red, white, yellow and sweet) and shallot from selected locations (Washington, Idaho, Oregon, Texas and Georgia) were determined using Fourier transform infrared (FT-IR) spectroscopy (4000–400 cm⁻¹). The Folin–Ciocalteu (F–C) assay was used to quantify TPC and three assays were used to determine TAC, including 2,2-diphenyl-picrylhydrazyl (DPPH) assay, Trolox equivalent antioxidant capacity (TEAC) assay and ferric reducing antioxidant power (FRAP) assay. Partial least squares regression (PLSR) with cross-validation (leave-one-out) was conducted on onion and shallot extracts (n = 200) and their corresponding F–C, DPPH, TEAC and FRAP values were employed to obtain four independent calibration models for predicting TPC and TAC for the extracts. Spectra from an extra 19 independent extracts were used as an external validation set for prediction. A correlation of r > 0.95 was obtained between FT-IR predicted and reference values (by F–C, DPPH, TEAC and FRAP assay) with standard errors of calibration (SEC) and standard errors of cross-validation (SECV) less than 2.85, 0.35 and 0.45 μmol Trolox/g FW of extracts for TEAC, FRAP and DPPH assay, respectively; and 0.36 mg gallic acid/g FW of extracts for the F–C assay. In addition, cluster analysis (principal component analysis (PCA)) and discriminant function analysis (DFA) could differentiate varieties of onions and shallot based upon infrared spectral features. Loading plots for the various chemometrics models indicated that hydroxyl and phenolic functional groups were most closely correlated with antioxidant capacity. The use of mid-infrared spectroscopy to predict the total antioxidant capacity of vegetables provides a rapid and precise alternative to traditional wet chemistry analysis.     

The effects of solvents on the phenolic contents and antioxidant activity of Stypocaulon scoparium algae extracts

Water, water/methanol (1/1), methanol and ethanol crude extracts from a brown alga Stypocaulon scoparium were examined for total phenolic contents (TPC) using Folin–Ciocalteu method. DPPH scavenging assay was performed to measure the radical scavenging activities (RSA) of the extracts. Results showed a significant association between the antioxidant potency and the TPC. The aqueous extract showed both, the highest antioxidant activity and highest phenolic contents. The identification and quantification of phenolic antioxidants were carried out with a rapid and simple method of reverse phase high performance liquid chromatography (RP-HPLC). This method was developed for the simultaneous analysis of 14 polyphenols, namely gallic acid, catechin, epicatechin, rutin, p-coumaric acid, myricetin, quercetin and protocatechuic, vanillic, caffeic, ferulic, chlorogenic, syringic and gentisic acids. The chromatographic separation of 14 polyphenols was achieved in less than 40 min by RP-HPLC (Varian, Pursuit XRs C18 column, 5 μm, 250 mm × 4.6 mm) using linear gradient elution of methanol and water (0.1% formic acid) with a flow rate of 1 ml/min. Gallic acid was by far the predominant polyphenol.     

Optimization of microwave-assisted extraction of phenolics from potato and its downstream waste using orthogonal array design

While other extraction methods have been tempted, a microwave-assisted extraction (MAE) method coupled with the orthogonal array design was investigated for efficient extraction of the phenolic compounds in potato downstream wastes. Four parameters were examined for the MAE of the total phenolic content (TPC) and optimized at 60% ethanol, 80 °C, 2 min, solid-to-solvent ratio 1:40 (g/ml). The MAE was proven more efficient than the conventional solvent extraction by refluxing. The optimized model showed that the downstream wastes, both the supernatant and the residue contained high TPC, particularly the former (11.0 ± 0.26 mg GAE/g DW). The antioxidant activities (DPPH and FRAP) closely correlated with the TPC of the samples (r = 0.92–0.97). Chlorogenic acid and caffeic acid were found to be the predominant phenolic acids. The extracts of the downstream wastes from potato processing can be a promising candidate for functional foods and nutraceutical ingredients.     

Phenolic acid analysis and antioxidant activity assessment of oil palm (E. guineensis) fruit extracts

Phenolic compounds in oil palm fruit (E. guineensis) were extracted in soluble free (SFP), insoluble-bound (ISBP) and esterified (EFP) forms. The total phenolic content (TPC) of the oil palm fruit extracts was determined using the Folin–Ciocalteu method and found to range from 5.03 to 9.04 g/L per g of dried weight (DW). The antioxidant activities of oil palm phenolic extracts were analysed using free radical scavenging assays and results showed that oil palm phenolic extracts contained antioxidant activities in the order of ISBP > EFP > SFP. Eight different phenolic acids were identified and quantified using a simple reversed-phase high performance liquid chromatography (HPLC) with a diode array detector (DAD) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Ferulic, p-hydroxybenzoic and p-coumaric acid were the dominant phenolic acids found in oil palm fruit extracts and ranged from 55 to 376 μg/g of DW.     

Total phenolic content and antioxidant capacity of extracts obtained from six important fruit residues

The extracts from kinnow peel, kinnow seeds, litchi pericarp, litchi seeds, grape seeds, and banana peel were screened for total phenolic content (TPC), trolox equivalent antioxidant capacity (TEAC), 1,1 diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, as well as reducing power. Kinnow peel extract exhibited the highest reducing power, TEAC, and DPPH free radical scavenging activity, whereas, the phenolic content of 37.4 mg GAE/g-dw was highest for grape seed extract. Banana peel extract with a low TPC showed the lowest reducing power, TEAC as well as DPPH free radical scavenging activity among the fruit residue extracts examined in the present study. Correlation analysis between the reducing power and DPPH radical scavenging ability; reducing power and ABTS radical scavenging activity; and ABTS and DPPH radical scavenging abilities showed a high degree of correlation (r² = 0.85-0.91). However, r² of 0.36, 0.66, and 0.49 between TPC and DPPH radical scavenging activity; TPC and reducing power; and TPC and ABTS radical scavenging ability, respectively, indicated that some non-phenolic compounds also contributed to the total antioxidant activity in fruit residue extracts examined in this study. To the best of our knowledge, this is the first paper presenting comprehensive data on TPC, reducing power, and antioxidant activity for the six fruit residues. This study demonstrated that kinnow peel, litchi pericarp, litchi seeds, and grape seeds, can serve as potential sources of antioxidants for use in food and pharmaceutical industry.     

Evaluation of antioxidant,antibacterial and anti-tyrosinase activities of four Macaranga species

The methanolic fresh leaf extracts of Macaranga gigantea, Macaranga pruinosa, Macaranga tanarius and Macaranga triloba were screened for their antioxidant properties (AOP), tyrosinase inhibition and antibacterial activities. Total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, ferric-ion reducing power (FRAP), ferrous-ion chelating (FIC) and lipid peroxidation inhibition (LPI) activities were used to evaluate the AOP. Modified 3,4-dihydroxy-L-phenylalanine (L-DOPA) method was used to determine tyrosinase inhibition activity, whereas antibacterial activity was determined using the disc-diffusion technique. TPC screening of the same species from different collection sites showed no significant difference between sites. M.triloba showed the highest ascorbic acid equivalent antioxidant activity (AEAC), FRAP and LPI values. M. tanarius, which showed the lowest TPC, AEAC, FRAP and LPI activities, exhibited the best FIC activity. M. pruinosa showed the best tyrosinase inhibition activity, whereas M. triloba showed the best antibacterial activity against Gram-positive bacteria species, with minimal inhibition dosage (MID) values as low as 10 μg/disc.     

A high antioxidant level in edible plants is associated with genotoxic properties

Aqueous extracts from 20 Malaysian edible plants were screened for total phenolic content (TPC), antioxidant activity and genotoxic effects on freshly isolated human lymphocytes. Ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assays were performed to determine the antioxidant activity of the extracts. Single-cell gel electrophoresis (SCGE) or comet assay was carried out to determine the level of DNA damage in human lymphocytes. Of the 20 plant aqueous extracts tested, two exerted more than 50% DNA strand breaks (severe damage), nine exerted 25–50% strand breaks (moderate damage) and nine exerted <25% strand breaks (mild damage). Strong positive correlations between the extent of DNA damage and FRAP level (r = 0.816), DNA damage and TPC (r = 0.830) and DNA damage and DPPH radical scavenging activities (r = 0.859) were observed. It is evident from this study that plants rich in antioxidants have greater genotoxic effect.     

Phytochemicals and antioxidant activity of different fruit fractions (peel,pulp, aril and seed) of Thai gac (Momordica cochinchinensis Spreng)

Three fractions (peel, pulp and aril) of gac fruit (Momordica cochinchinensis Spreng) were investigated for their phytochemicals (lycopene, beta-carotene, lutein and phenolic compounds) and their antioxidant activity. The results showed that the aril had the highest contents for both lycopene and beta-carotene, whilst peel (yellow) contained the highest amount of lutein. Two major phenolic acid groups: hydroxybenzoic acids and hydroxycinnamic were identified and quantified. Gallic acid and p-hydroxybenzoic acid were found in all fractions. Ferulic acid and p-hydroxybenzoic acid were most evident in pulp. Myricetin was the only flavonoid found in all fractions. Apigenin was the most predominant flavonoid in pulp (red), whereas rutin and luteolin gave the highest content in aril. The extracts of different fractions exhibited different levels of antioxidant activity in the systems tested. The aril extract showed the highest FRAP value. The greatest antioxidant activities of peel and pulp extracts were at immature stage, whereas those in the seed extracts increased from mature stage to ripe stage. The contents of total phenolic and total flavonoid in peel and pulp decreased during the fruit development stage (immature > ripe fruit) and subsequently displayed lower antioxidant capacity, except for the seed.     

Extraction and application of antioxidants from black glutinous rice

This research aimed to determine optimum extraction condition of black glutinous rice crude extract and to determine its application as an antioxidant in fish oil enriched mayonnaise. Black glutinous rice flour was extracted twice with 70:30 acetone-water mixture (v/v) at pH 2 and 6.8 for 2, 4 and 8 h of total extraction times. Total phenolic content (TPC), total monomeric anthocyanin content (TMA) and antioxidant activities as determined by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity assays of the crude extracts were measured. The extraction with pH 6.8 solvent for 4 h yielded the crude extract with significantly highest antioxidant activities analyzed by both FRAP and DPPH tests (p ≤ 0.05) although its TPC and TMA were not greatest. The freeze-dried extract from this condition was then added into fish oil enriched mayonnaise at 500 mg/kg and 1000 mg/kg (oil weight basis). Conjugated diene hydroperoxides (CDH), thiobarbituric acid reactive substance (TBARs) and color in CIELAB system of the mayonnaise samples stored at 30 °C were determined up to 30 days. The samples contained 1000 mg/kg crude extract had lowest rate of CDH and TBARs increase but had greatest extent of color deterioration, possibly due to anthocyanin degradation and Maillard reaction.     

Antioxidant activities of Sideritis congesta Davis et Huber-Morath and Sideritis arguta Boiss et Heldr: Identification of free flavonoids and cinnamic acid derivatives

Different solvent extracts of endemic Sideritis (Labiatae) species, Sideritis congesta Davis et Huber-Morath and Sideritis arguta Boiss et Heldr, were analyzed for free flavonoids (quercetin, apigenin, myricetin and kaempferol) and cinnamic acid derivatives (rosmarinic acid, ferulic acid, caffeic acid, p-coumaric acid and chlorogenic acid) using HPLC-DAD. All the phenolics were quantified in acid-hydrolyzed extracts, except rosmarinic acid, chlorogenic acid and myricetin which were quantified in raw samples. Antioxidant activities of extracts of these two plants and many of their components in pure form were evaluated based on DPPH^. and ABTS^.+ assays. In general, S. arguta extracts displayed higher antioxidant activity than S. congesta extracts possibly due to their richness in antioxidant components of strong activity. Acetone extract of S. arguta, with its strikingly high TEAC value of 3.2 mM trolox and low IC₅₀ value of 38.3 ??g/mL showed the highest antioxidant potency among all extracts. ??-tocopherol, the positive control, displayed IC₅₀ and TEAC values of 33.8 ??g/mL and 2.9 mM trolox, respectively. No direct correlation was found between antioxidant activities and total phenolic contents of the plant extracts studied.     

Comparative antioxidant activity of extracts from leaves,bark and catkins of Salix aegyptiaca sp.

Leaves, bark and catkins of Salix aegyptiaca L. were extracted into solvents of increasing polarity from cyclohexane (non-polar), butanol, ethanol and water (polar) and analysed for their antioxidant capacity, total phenol and flavonoids. The highest antioxidant activity (19 μg/ml IC₅₀ for inhibition of DPPH radical activity), total phenolic content (212 mg gallic acid equivalents/g of dried extract) and total flavonoid (479 mg catechin equivalents/g of dried extract) was observed in the ethanolic extract of bark. HPLC identification of phenolic compounds from the extracts indicated the presence of gallic acid, caffeic acid, vanillin and p-coumaric acid, myricetin, catechin, epigallocatechin gallate, rutin, quercetin as well as salicin. Our data indicates the presence of high amounts of phenols and flavonoids in different parts of S. aegyptiaca species and propose that extracts from this plant may be utilised as a source of health promoting antioxidants.     

Antioxidant activity of Camellia sinensis leaves and tea from a lowland plantation in Malaysia

Methanol extracts of fresh tea leaves from a lowland plantation in Malaysia were screened for total phenolic content (TPC) and antioxidant activity (AOA). AOA evaluation included 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging ability, ferric-reducing antioxidant power (FRAP), and ferrous-ion chelating (FIC) ability. Ranking, based on TPC and AOA, was as follows: shoots > young leaves > mature leaves. TPC and AOA of lowland leaves were comparable to those of highland plants. A green tea produced by drying young leaves in a household microwave oven for 4 min showed significantly higher TPC and AOA than did four commercial brands of green and black tea.     

Polyphenol contents and in vitro antioxidant activities of lyophilised aqueous extract of kiwifruit (Actinidia deliciosa)

The aim of this study was to determine the antioxidant potency and total phenolic and flavonoid contents of kiwifruit (Actinidia deliciosa) in vitro by analysing the radical scavenging activity of lyophilised water extract from kiwifruit (LEK) for 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-picryl-hydrazyl (DPPH), N,N-dimethyl-p-phenylenediamine (DMPD), and superoxide anion radical (O₂⁻) as well as the total reducing power by FRAP and CUPRAC assays and the metal chelating activities. LEK showed efficient radical scavenging activity with DPPH, ABTS, DMPD, and O₂⁻ radicals; ferric (Fe³⁺) and cupric (Cu²⁺) ion reducing power and metal chelating activities. Moreover, the amounts of phenolic compounds, such as caffeic acid, ferulic acid, syringic acid, ellagic acid, catechol, pyrogallol, p-hydroxy benzoic acid, vanillin, p-coumaric acid, gallic acid, quercetin, ??-tocopherol and ascorbic acid, in LEK were quantified by LC-MS-MS. The results show that pyrogallol (2070.0 mg/kg LEK) is the main phenolic compound responsible for the antioxidant and radical scavenging activities of LEK. Finally, total phenolic and flavonoid contents were determined as gallic acid (GAE) and quercetin equivalents (QE). The GAE and QE values in LEK were 16.67 ± 2.83 ??g GAE/mg and 12.95 ± 0.52 ??g QE/mg, respectively. The results suggest that consumption of kiwifruit (A. deliciosa) can be beneficial effects due to its antioxidant properties.     

Potassium rate alters the antioxidant capacity and phenolic concentration of basil (Ocimum basilicum L.) leaves

In the current study, we have determined how potassium rate affects the phenolic levels and antioxidant properties of three cultivars of basil (Ocimum basilicum L.) leaves: Dark Opal, Sweet Thai, and Genovese. Potassium rate increased the total phenolic concentration in basil, with basil treated at the highest potassium rate, 5.0 mM K, containing greater phenolic levels than basil treated at the lowest potassium rate, 1.0 mM K (p = 0.008). Basil grown at 5.0 mM K also had higher concentrations of rosmarinic (p = 0.005) and chicoric (p < 0.001) acids compared to lower potassium treatment levels. Correspondingly, 1.0 mM K basil had lower DPPH (2,2′-diphenyl-1-picrylhydrazyl) (p ? 0.005) and FRAP (ferric reducing antioxidant power, p = 0.043) antioxidant capacities compared to basil treated at higher potassium rates. Cultivar was also found to impact the phenolic composition and antioxidant properties of basil, with Sweet Thai having lower total phenolic concentrations and FRAP antioxidant capacities than Dark Opal and Genovese. Although not affected by potassium rate, anthocyanin concentrations varied significantly among the cultivars, with purple Dark Opal basil exhibiting higher anthocyanin levels than Sweet Thai (p = 0.003) and Genovese (p = 0.002).     

Phytochemical and antioxidant characterization of mamey (Pouteria sapota Jacq. H.E. Moore & Stearn) fruit

Phytochemical compounds in fruits and vegetables have gained great importance in the last few years because of the increasing evidence suggesting their antioxidant and prevention of chronic diseases. Carotenoids, phenolics, flavonoids, and vitamins E and C, are among these phytochemicals. Several fruits have been characterized so far for their antioxidant and health properties but there is still limited information on fruits from the tropic. Therefore, the objective of this study was the characterization of mamey fruit (Pouteria sapota Jacq. H. E. Moore & Stearn) with regard to their antioxidant capacity and phytochemical profile. Phenolics, carotenoids and ??-tocopherol were quantified and identified by HPLC-DAD-Mass Spectrometry (LC-MS), and DPPH and FRAP assays were used to evaluate antioxidant capacity. Hydrophilic extracts of mamey fruit showed higher antioxidant capacity than the lipophilic portion. Total soluble phenols content was 28.5 mg GAE/100 g fw, being p-hydroxybenzoic acid as the main phenolic that was identified. Total carotenoid content was 1127.9 ??g ??-carotene/100 g fw with ??-carotene being the main contributor, in addition to lutein, and violoxanthin. Concentration of ??-tocopherol was 360.0 ??g/100 g fw. Results of this study suggest that mamey fruit is a good source of carotenoids and its inclusion in the diet is recommended.     

Variation in antioxidant potential and total polyphenol content of fresh and fully-fermented Sri Lankan tea

Tea polyphenols possess antioxidant properties and have been shown to have a protective effect against several degenerative diseases. The study aimed to determine the amounts of polyphenols and antioxidant properties for teas grown in Sri Lanka, over a period of 10 months. Water extracts of freeze-dried fresh (unfermented) and fully-fermented tea leaves were made for a structured set of samples (fermented and unfermented teas from six plantations; teas representing two harvesting seasons from four plantations) collected from the main tea growing regions in Sri Lanka. Total phenolic content (TPC), the ferric reducing antioxidant power (FRAP) and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity were determined for each sample. The results highlight significant (P < 0.05) variations in antioxidant activity across the six plantations. FRAP and DPPH for both fermented and unfermented teas from the four highland plantations showed a significant (P < 0.05) interaction between season and plantation. A similar interaction between season and plantation was observed for total phenolics in unfermented teas from the four highland plantations. The variability of the total phenolics for fermented teas, however, was independent of seasonal variations. A significant correlation (r = 0.5, P < 0.05) was observed between FRAP and total phenolics.     

Principal phenolic phytochemicals and antioxidant activities of three Chinese medicinal plants

The principal antioxidant components and content of cinnamon (Cinnamomum cassia), turmeric (Curcuma longa) and golden thread (Coptidis rhizoma) extracts were determined using high performance liquid chromatography (HPLC) with UV detection. In general, C. cassia, C. longa and C. rhizoma extracts from domestic Taiwan were rich in cinnamaldehyde, curcumin, and berberin, respectively. The contents of cinnamaldehyde, curcumin, and berberin in the acetone extracts were 1911, 2029, and 840 mg l⁻¹, respectively. The Folin–Ciocalteu method was used to measure the total phenolic concentrations of extracts, which had the content of 9.6 (C. cassia), 2.6 (C. longa), and 4.3 (C. rhizoma) mM l⁻¹. In addition, DPPH radical-scavenging, ferric-reducing antioxidant power (FRAP), and ferric thiocyanate (FTC) assays were employed to measure antioxidant activities. The C. cassia fresh extracts had higher antioxidant activities which were 84–90% (DPPH), 17–33 μmol l⁻¹ (FRAP), and 53–82% (FTC). The activities of C. longa fresh extracts were 22–44% (DPPH), 7–11 μmol l⁻¹ (FRAP), and 53–81% (FTC) while C. rhizoma were 53–64% (DPPH), 18–26 μmol l⁻¹ (FRAP), and 59–82% (FTC).