3. Biological studies in fruit, leaf, and fig spirits and liqueurs

The leaves and fruits of F. carica are important in traditional medicine [24]. Many biological activities have been evaluated and confirmed on F. carica extracts, and the bioassay-guided fractionation in most cases allowed to assign the chemical structures responsible of such biological effects, thereby ratifying some of its folkloric uses [9]. In this section we analyzed the potential health-promoting constituents of fig fruits, leaves, and derived products, fig liqueurs, and spirits [6].

#### 3.1 Antioxidant capacity

hydroxycinnamic acids such as caffeic acid (141), and the hydroxybenzoic acids, gallic (148) and syringic (149) acids, were only present in fruits [32]. Also the ferulic acid hexoside and the coumaroyl and ferulic hexosides were present in fruits. Moreover, the following compounds were common to both leaves and fruits: the

hydroxybenzoic derivatives, dihydroxybenzoic acid attached to hexoside/hexoside pentoside/pentoside/di-pentoside, vanillic acid glucoside, and gallic acid dipentoside; and the hydroxycinnamic acids, ferulic acid (140) and the chlorogenic (3-O-caffeoylquinic acid) (144) and neochlorogenic (5-O-caffeoylquinic acid) (145) acids. The common hydroxycinnamic derivatives present in fruits and leaves were caffeoylquinic acid hexoside, dihydrocaffeic acid hexose, and the sinapic acid

Flavonols such as quercetin (151) and glycosylated flavonols such as rutin (quercetin-3-O-rutinoside) (154) (major individual phenolic identified in fruits

glucoside (157), quercetin di-deoxyhexoside hexoside, and quercetin O-di-hexoside were confirmed in fresh and dried figs and leaves [32]. Nicotiflorin (kaempferol-3-O-rutinoside) (152) and quercetin-acetilglucoside (156) were reported in fruits, while astragalin (kaempferol 3-O-glucoside) (153) only in leaves [2, 3, 9, 24, 31, 33]. Free flavones such as luteolin (158) and apigenin (159) are present in fig fruits and leaves. Also, the glycosylated flavones, isoorientin (luteolin 6-C-glucoside) (160), orientin (luteolin 8-C-glucoside) (161), cynaroside (luteolin 7-O-glucoside) (162), vitexin (apigenin 8-C-glucoside) (164), isochaftoside (apigenin 6-Cglucoside 8-C-arabinoside) (165), and apigenin 6-C-hexose-8-C-pentose [which could be identified as schaftoside (apigenin 6-C-glucoside 8-C arabinoside)], were detected in both plant parts. However, apigenin 7-rutinoside (163) and luteolin 6C-

Another group of flavonoids identified was the flavanones, with the compounds eriodictyol (166) and eriodictyol hexoside in fruits and naringenin (167) in fruits and leaves. The flavanonol taxifolin (dihydroquercetin) (168) was identified in fruits [32]. The flavanols, (+)-catechin (169) in fruits and leaves and (�)-

Genistein (173) and hydroxygenistein methyl ether malonylhexoside in leaves and prenylhydroxygenistein, prenylgenistein (171), biochanin A (genistein 4<sup>0</sup>

Different anthocyanin pigments, some of them containing cyanidin or pelargonidin as aglycones, as well as rutinose and glucose substituting sugars and acylation with malonic acid, were found in skin and pulp from different varieties of Iberian fresh figs with different colors (black, red, yellow, and green). These compounds include (epi)-catechin-(4-8)-cyanidin-3-glucoside, (epi)catechin-(4–8)-

cyanidin-3-rutinoside,(epi)catechin-(4,8)-pelargonidin 3-rutinoside, 5 carboxypyranocyanidin-3-rutinoside, cyanidin-3-malonylglicosyl-5-glucoside, cyanidin-3-malonylglucoside, cyanidin-3-glucoside (175), cyanidin-3,5-diglucoside (176), cyanidin 3-O-rutinoside (as the main anthocyanin in different commercial fig varieties [2]) (178), pelargonidin-3-glucoside (179), pelargonidin-3-rutinoside (180) and peonidin-3-rutinoside (181). In addition, 5-carboxypyranocyanidin-3 rutinoside, a cyanidin 3-rutinose dimer, and five condensed pigments containing C–C linked anthocyanins and flavanol (catechin and epicatechin) residues were

Coumarin (182); the hydroxycoumarins esculetin hexoside, dihydroxy-

coumarin, umbelliferone (7-hydroxycoumarin) (183), and prenyl-7 hydroxycoumarin; and the furocoumarins psoralen (187) and bergapten




hydroxybenzoic acids, di-/hydroxybenzoic acids and vanillic acid; the

[2]), isoquercetin (quercetin-3-O-glucoside) (155), quercetin 3-O-(60

hexose-8C-pentose were present in fruits [2, 9, 33].

epicatechin (170) in leaves, were also identified [3, 33].

and leaves, were the isoflavones identified [2, 3, 9, 24, 31, 33].

methyl ether) (172), and cajanin (7-methoxy 2<sup>0</sup>

identified [9].

122

hexoside [2, 9, 24, 32].

Modern Fruit Industry

Among the different phytochemicals studied in F. carica, phenolic compounds are among the most important with antioxidant capacity (AC). Many of these compounds are able to act as antioxidants by different ways: reducing agents, hydrogen donators, free radical scavengers, singlet oxygen quenchers, and so forth [2].

#### 3.1.1 Fig spirits and liqueurs

The antioxidant capacity (AC) by ABTS [2,2<sup>0</sup> -azinobis-(3-ethylbenzothiazoline-6-sulfonate)] and DPPH (1,1-diphenyl-2-picrylhydrazyl) assays and the total phenolic content (TPC) by Folin–Ciocalteu method were evaluated in different fig spirits and liqueurs [34]. Fig liqueurs showed high values of TPC and AC (ABTS), close to the values of other fruit spirits with highest AC such as green walnut, carob pod, and mulberry. Fig spirits presented high (third value of 15 samples) AC by ABTS assay and among the highest TPC values. However, no DPPH scavenging activity was shown for fig liqueurs and spirits.

#### 3.1.2 Leaf extracts

The maximum total flavonoid content (25.04 mg/g) with marked scavenging activities against hydroxyl and superoxide anion free radicals in a concentrationdependent manner were found in ethanolic (40%) leaf extracts of F. carica (solid to liquid ratio 1:60 g/mL, temperature extraction of 60°C, and 50 min of ultrasonic treatment) [6].

#### 3.1.3 Fruit extracts

Several works studied the AC of fruit extracts. Extracts from six commercial fig varieties were evaluated for AC by ferric reducing antioxidant method (FRAP) and also for TPC and total flavonoid content (TFC) and amount and profile of anthocyanins. The extracts exhibiting the highest AC contained the highest levels of TPC and TFC and anthocyanins (cyanidin-3-O-rutinoside as the main compound) [2, 6]. In another work, two fruit extracts [water (WE) and crude hot water-soluble polysaccharide (PS)] were evaluated for AC using the in vitro scavenging abilities

on DPPH, superoxide, and hydroxyl radicals and reducing power assays. Both extracts have notable scavenging activities on DPPH [WE (EC50, 0.72 mg/ml) and PS (EC50, 0.61 mg/ml)], while PS showed highest scavenging activity on superoxide radical (EC50, 0.95 mg/ml) and hydroxyl anion radical (43.4% at concentration of 4 mg/ml) [6].

significant differences as a function of diabetes with the vitamin E/C 18:2 ratio

152.1 80.3 μg/mg) and the vitamin A/C 18:2 ratio being raised relative to the untreated diabetic rats by the administration of the basic fraction (91.9 14.5 μg/

The treatment of diabetes and obesity using the inhibition of carbohydrate (αamylase and α-glucosidase) and lipid (pancreatic lipases)-digesting enzymes is used to reduce the digestion and absorption of carbohydrates and lipids and also to reduce significantly the blood glucose and body fat levels. Ethanolic extracts from fruits and leaves, in relation to hexane, ethyl acetate, and aqueous extracts,

presented the higher α-amylase and α-glucosidase and pancreatic lipase inhibitions at the higher concentration tested (500 μg/mL). At this concentration, similar values to that of the standard acarbose were found for α-amylase and α-glucosidase

Different works on antidiabetic activity were carried out using methanolic and aqueous leaf extracts [2, 6]. The maximum glucose-lowering effect in induced diabetic rats with alloxan was observed with methanolic extracts at a concentration of 200 mg/kg and after 21 days. At these conditions, results were similar to those obtained with metformin (medication used for the treatment of type 2 diabetes). On the other hand, a clear hypoglycemic effect and reduction of total cholesterol and total cholesterol/HDL cholesterol ratio of the oral or intraperitoneal administration of aqueous leaf extracts in relation to the control group was observed in

In other work, an 8-week-old rooster's liver with high abdominal fat was used to

evaluate the potential of leaf fig extract as food supplement to decrease hepatic triglyceride (TG) content and secretion of TG and cholesterol from the liver. Results showed that the leaf extract reduced the contents to the basal level in a concentration-dependent manner [2]. Another work about the intraperitoneal

hypertriglyceridemia-induced rats with 20% emulsion of long chain triglycerides (LCTG) indicated a decrease in the LCTG content of 84% after 60 min and a reduction of 69% after 2 h. The results suggest the existence of compound/s in fig

The hepatoprotective activity of methanolic leaf extract in carbon tetrachlorideinduced hepatotoxicity in rats was evaluated, and the activity was comparable to

administration of leaf decoction extracts (50 g dry wt/kg body wt) in

leaf decoction that influence the lipid catabolism [6].

that of the known hepatoprotective silymarin [6].

3.4 Antidiabetic, hypocholesterolaemic, and hypolipidemic activities

3.3 Inhibitory activities of the enzymes α-amylase, α-glucosidase, and

being normalized by the administration of the chloroform fraction (to

Chemical and Biological Characteristics of Ficus carica L. Fruits, Leaves...

DOI: http://dx.doi.org/10.5772/intechopen.86660

mg) [2].

pancreatic lipase

3.3.1 Fruit and leaf extracts

3.4.1 Leaf extracts

inhibitions in fruit ethanolic extracts [35].

diabetic rats induced with streptozotocin.

3.5 Hepatoprotective activity

3.5.1 Leaf extracts

125

Ethanolic extracts from the white Beni Maouche Algerian figs were compared with carob pods and holm oak acorns [7]. Fig extracts presented lower efficacy to scavenge DPPH (20.54 0.30%) than ABTS radicals (68.98 0.12%) and higher reducing ability in phosphomolybdenum assay (638.23 0.43 mg GAE/100 g). This extract (73.17 0.16%) also inhibited the formation of the complex Fe2+-ferrozine and was also able to scavenge H2O2 efficiently. The extracts from the three fruits evaluated (carob, acorns, and figs) showed no significant differences in nitric oxide (NO) radical scavenging activities [7].

#### 3.2 Reactive oxygen species production, xanthine oxidase inhibition assay, and study of oxidative stress

#### 3.2.1 Fruit extracts

The production of reactive oxygen species (ROS) in the presence of ethanolic fig extract was measured by chemiluminescence using lucigenin. This method is widely used to determine the rate of superoxide radicals in human neutrophils. Fig extract inhibited the chemiluminescence of lucigenin and ROS production and differed from each other according to the concentration of the sample and the incubation time. After 15 min of treatment, the extract tested at the highest concentration (250 μg/mL) seemed to reach its higher level of lucigenin inhibition, value 44% below that obtained with diphenylene iodonium (0.2 mM), the standard selective inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase tested [7].

Ethanolic fig extracts were able to inhibit the activity of the enzyme xanthine oxidase (XO), an enzyme that generates reactive oxygen species. Different extract concentrations were evaluated (50, 250, and 500 μg/mL), and at 250 μg/mL, ethanolic extracts presented the best inhibition, although its value is much lower (practically half) of that obtained with the positive control allopurinol, a drug clinically used for gout treatment. The extracts tested at 500 μg/mL showed a decrease in the inhibition of XO activity as the result of its prooxidant effect. The strong correlation coefficients between XO inhibition activity and phenolic compounds and flavonoids demonstrate the inhibition activity of XO [7].

#### 3.2.2 Leaf extracts

Oxidative stress is the disturbance in the balance between the production of reactive oxygen species (free radicals) and antioxidant defenses. The role of these free radicals in the production of tissue damage in diabetes mellitus was studied in rats divided into four groups: streptozotocin-induced diabetic rats, diabetic rats that received a single dose of a basic fraction of F. carica leaf extract, diabetic rats that received a single dose of a chloroform fraction of the extract, and normal rats. Antioxidant status was affected in the diabetes syndrome, and F. carica extracts showed that they normalize it. Diabetic animals exhibited higher values for erythrocyte catalase activity, plasma levels of vitamin E, monounsaturated and polyunsaturated fatty acids, saturated fatty acids and linoleic acid than that of the control group. Both F. carica fractions showed that they normalize the values of the diabetic animal's fatty acids and plasma vitamin E values. They showed statistically

Chemical and Biological Characteristics of Ficus carica L. Fruits, Leaves... DOI: http://dx.doi.org/10.5772/intechopen.86660

significant differences as a function of diabetes with the vitamin E/C 18:2 ratio being normalized by the administration of the chloroform fraction (to 152.1 80.3 μg/mg) and the vitamin A/C 18:2 ratio being raised relative to the untreated diabetic rats by the administration of the basic fraction (91.9 14.5 μg/ mg) [2].

### 3.3 Inhibitory activities of the enzymes α-amylase, α-glucosidase, and pancreatic lipase

#### 3.3.1 Fruit and leaf extracts

on DPPH, superoxide, and hydroxyl radicals and reducing power assays. Both extracts have notable scavenging activities on DPPH [WE (EC50, 0.72 mg/ml) and PS (EC50, 0.61 mg/ml)], while PS showed highest scavenging activity on superoxide radical (EC50, 0.95 mg/ml) and hydroxyl anion radical (43.4% at concentration

Ethanolic extracts from the white Beni Maouche Algerian figs were compared with carob pods and holm oak acorns [7]. Fig extracts presented lower efficacy to scavenge DPPH (20.54 0.30%) than ABTS radicals (68.98 0.12%) and higher reducing ability in phosphomolybdenum assay (638.23 0.43 mg GAE/100 g). This extract (73.17 0.16%) also inhibited the formation of the complex Fe2+-ferrozine and was also able to scavenge H2O2 efficiently. The extracts from the three fruits evaluated (carob, acorns, and figs) showed no significant differences in nitric oxide

3.2 Reactive oxygen species production, xanthine oxidase inhibition assay,

After 15 min of treatment, the extract tested at the highest concentration

The production of reactive oxygen species (ROS) in the presence of ethanolic fig extract was measured by chemiluminescence using lucigenin. This method is widely used to determine the rate of superoxide radicals in human neutrophils. Fig extract inhibited the chemiluminescence of lucigenin and ROS production and differed from each other according to the concentration of the sample and the incubation time.

(250 μg/mL) seemed to reach its higher level of lucigenin inhibition, value 44% below that obtained with diphenylene iodonium (0.2 mM), the standard selective inhibitor of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase tested [7].

Ethanolic fig extracts were able to inhibit the activity of the enzyme xanthine oxidase (XO), an enzyme that generates reactive oxygen species. Different extract concentrations were evaluated (50, 250, and 500 μg/mL), and at 250 μg/mL, ethanolic extracts presented the best inhibition, although its value is much lower (practically half) of that obtained with the positive control allopurinol, a drug clinically used for gout treatment. The extracts tested at 500 μg/mL showed a decrease in the inhibition of XO activity as the result of its prooxidant effect. The strong correlation coefficients between XO inhibition activity and phenolic compounds and flavonoids demonstrate the inhibition activity of XO [7].

Oxidative stress is the disturbance in the balance between the production of reactive oxygen species (free radicals) and antioxidant defenses. The role of these free radicals in the production of tissue damage in diabetes mellitus was studied in rats divided into four groups: streptozotocin-induced diabetic rats, diabetic rats that received a single dose of a basic fraction of F. carica leaf extract, diabetic rats that received a single dose of a chloroform fraction of the extract, and normal rats. Antioxidant status was affected in the diabetes syndrome, and F. carica extracts showed that they normalize it. Diabetic animals exhibited higher values for erythrocyte catalase activity, plasma levels of vitamin E, monounsaturated and polyunsaturated fatty acids, saturated fatty acids and linoleic acid than that of the control group. Both F. carica fractions showed that they normalize the values of the diabetic

animal's fatty acids and plasma vitamin E values. They showed statistically

of 4 mg/ml) [6].

Modern Fruit Industry

3.2.1 Fruit extracts

3.2.2 Leaf extracts

124

(NO) radical scavenging activities [7].

and study of oxidative stress

The treatment of diabetes and obesity using the inhibition of carbohydrate (αamylase and α-glucosidase) and lipid (pancreatic lipases)-digesting enzymes is used to reduce the digestion and absorption of carbohydrates and lipids and also to reduce significantly the blood glucose and body fat levels. Ethanolic extracts from fruits and leaves, in relation to hexane, ethyl acetate, and aqueous extracts, presented the higher α-amylase and α-glucosidase and pancreatic lipase inhibitions at the higher concentration tested (500 μg/mL). At this concentration, similar values to that of the standard acarbose were found for α-amylase and α-glucosidase inhibitions in fruit ethanolic extracts [35].

#### 3.4 Antidiabetic, hypocholesterolaemic, and hypolipidemic activities

#### 3.4.1 Leaf extracts

Different works on antidiabetic activity were carried out using methanolic and aqueous leaf extracts [2, 6]. The maximum glucose-lowering effect in induced diabetic rats with alloxan was observed with methanolic extracts at a concentration of 200 mg/kg and after 21 days. At these conditions, results were similar to those obtained with metformin (medication used for the treatment of type 2 diabetes). On the other hand, a clear hypoglycemic effect and reduction of total cholesterol and total cholesterol/HDL cholesterol ratio of the oral or intraperitoneal administration of aqueous leaf extracts in relation to the control group was observed in diabetic rats induced with streptozotocin.

In other work, an 8-week-old rooster's liver with high abdominal fat was used to evaluate the potential of leaf fig extract as food supplement to decrease hepatic triglyceride (TG) content and secretion of TG and cholesterol from the liver. Results showed that the leaf extract reduced the contents to the basal level in a concentration-dependent manner [2]. Another work about the intraperitoneal administration of leaf decoction extracts (50 g dry wt/kg body wt) in hypertriglyceridemia-induced rats with 20% emulsion of long chain triglycerides (LCTG) indicated a decrease in the LCTG content of 84% after 60 min and a reduction of 69% after 2 h. The results suggest the existence of compound/s in fig leaf decoction that influence the lipid catabolism [6].

#### 3.5 Hepatoprotective activity

#### 3.5.1 Leaf extracts

The hepatoprotective activity of methanolic leaf extract in carbon tetrachlorideinduced hepatotoxicity in rats was evaluated, and the activity was comparable to that of the known hepatoprotective silymarin [6].

Petroleum ether leaf extract also showed significant reversal of biochemical, histological, and functional changes in oral rifampicin (50 mg/kg)-induced hepatotoxicity in rats [2].

Bursaphelenchus xylophilus, Panagrellus redivivus, and Caenorhabditis elegans with

Fruit extract was found useful in protecting from bacterial pathogen attack in tomatoes [6]. Anthelmintics are drugs that either kill or expel infesting helminths living in the gastrointestinal tract or tissues. Helminths cause numerous damages to the host, for example, injury to organs, intestinal or lymphatic obstruction, causing blood loss, depriving it of food, and secreting toxins [36]. The potential of cysteine proteinases extracted from figs as a potential anthelmintic was evaluated. The experiments were carried out in vitro using the rodent gastrointestinal nematode Heligmosomoides polygyrus. A marked damage was visible within a 2-h incubation period of cysteine proteinases on the cuticle (loss of surface cuticular layers) of adult male and female H. polygyrus worms. The results (efficacy and mode of action) proved the potential use of cysteine proteinases as anthelmintics [6].

To evaluate the antipyretic activity, different doses (100, 200, and 300 mg/kg body wt. p.o.) of ethanolic leaf extracts showed significant dose-dependent reduction in normal body temperature and yeast-induced elevated temperature (pyrexia) in albino rats. The antipyretic effect of this extract was comparable to that of the standard antipyretic agent paracetamol at 150 mg/kg body wt., p.o. The effect extended up to 5 hours after drug administration compared to that of paracetamol

Colorimetric microplate-based assay of methanolic (80%) leaf extract exhibited

Calpains are calcium-dependent enzymes that determine the fate of proteins through regulated proteolytic activity. These enzymes have been linked to the modulation of memory and are keys to the pathogenesis of Alzheimer disease [37]. Calpain activity was examined after treatment of cells with dry extracts. Fig extracts decreased the fluorescence of the fluorogenic calpain substrate tertbutoxycarbonyl-Leu-Metchloromethylaminocoumarin (t-boc-LM-CMAC) and consequently inhibited the activity of calpain. Fig extracts showed the same capacity to inhibit calpain as carob and holm oak acorn extracts. The incubation time (2, 4, and 6 h) and the concentrations tested (25, 100, and 250 μg/ml) had no effect on the inhibitory activity of calpain in the presence of fig extracts. After 2 h of treatment, the extracts already inhibited more than 50% for all the concentrations tested. This inhibitory activity of the studied extracts could be attributed to its

effect against Mycobacterium tuberculosis strain H37Rv with MIC value of

74.3, 96.2, and 98.4% mortality, respectively, within 72 h [2].

Chemical and Biological Characteristics of Ficus carica L. Fruits, Leaves...

DOI: http://dx.doi.org/10.5772/intechopen.86660

3.10.2 Fruit extracts

3.11 Antipyretic activity

(150 mg/kg.b.wt., p.o.) [2, 6].

3.12 Antituberculosis activity

3.11.1 Leaf extracts

3.12.1 Leaf extracts

1600 μg/mL [2].

3.13.1 Fruit extracts

127

3.13 Anti-calpain activity
