Introduction

Approximately 70-80% of the world’s population, primarily in developing countries, still relies primarily on medicinal plants as their major source of healthcare since they are more commonly accepted culturally.¹ Phytochemicals are organic substances that are present in various plant sections.² Crude extracts and dry powder samples from medicinal plants and their species have recently attracted interest in the development and production of alternative traditional medicine.³ Linoleic and alpha-linolenic acid cannot be produced by the human body; they must be consumed through diet.⁴ Since ancient times, the oils found in the seeds of these plants have been used to strengthen the body. They have also traditionally been used as a diuretic.⁵ Fruits also contain oleic acid, which is widely known for its ability to strengthen the immune system and lower the risk of diseases brought on by reactive oxygen species .⁶ Fruit growth is accompanied by the simultaneous accumulation of sugars and organic acids, albeit at different developmental stages. Both concentration and metabolic processes differ substantially between species. Accordingly, it has been discovered that as sweet fruits such as apples, litchi, melons, peaches, and strawberries ripen, sucrose, glucose, and fructose accumulate in them.⁷ The search for herbal medicinal plants with possible medicinal properties is crucial due to their ethno-medical usage, as well as their isolation, characterization, and conservation.⁸ Traditional plants from the Maznie region that were the focus of ethnobotanical studies, like the Celtis tournefortii Lam and Prosopis farcta are discussed in this manuscript. 

Maznie Subistrict is located 135 kilometers from the center of Erbil Kurdistan region of Iraq. It has a vast range of plant species. Maznie region experiences a Mediterranean climate with cold winters and hot summers, and the center district receives more than one meter of snow each year. It has long been suggested that some tree species could be used as animal feed in arid regions. Because of this, edible wild plants offer a significant nutritional value for humans. For example, they include vitamins, antioxidants, carbs, lipids, and proteins.⁹ From wild edible plants, several medicines and therapies have been created over the years.¹⁰ Traditional treatments for a variety of conditions, including arthritis, eczema, cancer, diarhea, diabetes, hypertension, cardiovascular issues, renal disorders, and joint pain, use the Celtis tournefortii Lam species.¹¹

A deciduous tree, Celtis tournefortii Lam, which belongs to the family Cannabaceae can reach a height of 6 meters in plains and dry woods in hot climates. According to Yldrm et al.¹² numerous nations, including Kurdistan in Iraq, Turkey, Iran, Ukraine, Croatia, Greece, and Azerbaijan, are fond of this tree’s edible fruits. It is called Hackberry in English and Tawk in Kurdish. Perennial shrub Prosopis farcta, which belongs to the family Fabaceae (Leguminosae) grows to a height of 30 to 100 cm and is a common plant in the Middle East, where it dominates the entire belt of Mediterranean-style alluvial soils used for agriculture. It is called Syrian mesquite in English and Khrnuk in kurdish. It can be found in Iraq in a range of environments, from the North to the South.¹³ Kurdish people utilized Prosopis farcta leaves or beans as a traditional medicine to treat conditions like colds, diarrhea, inflammation, measles, diabetes, skin problems, prostate abnormalities, wound healing, gastrointestinal problem, stomach ache and chest pain.¹⁴ The phytochemical and antioxidant properties of Celtis tournefortii Lam and Prosopis farcta have not been thoroughly investigated and reported in the Maznie sub-district of Kurdistan region. However, various studies conducted in the past have demonstrated that both Celtis tournefortii Lam and Prosopis farcta plants have therapeutic uses in both Iranian and Turkish., Celtis tournefortii Lam leaves and fruit, Prosopis farcta pod and seed were grown in their native habitats in Maznie subdistrict, and this study was therefore designed to evaluate the chemical components, polyphenols and fatty acids content of these wild plants.

Material and Methods

Description of the study area

The Mergasor district is divided into five subdistricts (Sherwan Mazn, Barzan, Goretu, Piran, Maznie) as shown in (Figure 1). Maznie subdistrict is made up of 31 villages and 25 kilometers away from Mergasor District’s. The global position system (GPS) coordinates for these locations were 36°47’28.5″N latitude and 44°25’24.5″E longitude. Celtis tournefortii Lam (voucher species: (ESUH7901) and Prosopis farcta (voucher species: ESUH7913) were collected in November 2021 from the Maznie sub-district (Figure 2). Plants identified by a National Herbarium of Kurdistan expert, coded, and kept at the Salahaddin University Herbarium Education College’s herbarium (ESUH7901 and ESUH7913).

Figure 1: Maps showing the location of the research area. A. Iraqi map B. Mergasur district C. Maznie subdistrict. Click here to view Figure

Figure 2: Trees of study area, A. Celtis Tournefortii-lam, B. Prosopis farcta Click here to view Figure

Collect plant samples

Leaves, ripe fruits, pods and seeds wild trees were used as sources for the randomly selected plant samples. Each tree in the plant specimen had three copies. Wild plant samples were dried in the shade (Figure 3). Before the leaves, fruits, pods and seeds were mashed then stored as a homogenous powder at -80 °C until extraction. 

Figure 3: leaves, fruits Celtis tournefortii Lam, and pods, seeds of Prosopis farctal.  Click here to view Figure

Proximate analysis

According to the official analysis procedures from the Association of Official Analytical Chemists, ¹⁵ proximate analyses were used to determine the amounts of ash, moisture, protein, fat, and carbohydrates in the samples. 

Total antioxidant

The total antioxidant was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) DPPH standard, following the procedure employed by Brand-Williams et al.¹⁶ 

Vitamin C

Utilizing the titration method and 1, 2-dichlorophenol indophenol (DCIP) solution vitamin C was measured as described by Mokhtarpour et al.¹⁷ 

Total sugar

One milliliter of standard solution or properly diluted sample was combined with 0.5 milliliters of 0.1N HCl. The mixture was boiled in a 100°C water bath for 15 minutes before being immersed in cold water to cool it.  Half milliliter of 0.1N NaOH was added while mixing after cooling. Nelson’s decreasing sugar test was used to measure the obtained sample solution’s total sugar concentration.¹⁸ 

Polyphenol extraction

Two gram of the powdered samples were taken out in order to extract the polyphenols. Four milliliter of a methanol solution having 1% acetic acid was added. Ultrasonic waves were then used to conduct the solvent extraction for 20 minutes. The phenolic acids were isolated, recognized, and quantified using the high-performance liquid chromatography (HPLC) apparatus model 1100 series (Agilent USA).  It was set up with a 20 microliter injection loop, four solvent gradient pumps, a degassing system, a column oven (set at 25°C), and a diode array detector with settings for 250, 272, and 310 nm, respectively.²¹

Total phenolic content 

According to Iqbal et al¹⁹, the total phenolic content of the plant sample was ascertained using the modified Folin-Ciocalteu technique. The amount of phenolic in extracts was then quantified as mg GAE/g extract (gallic acid equivalents).

Total flavonoids content

The aluminium chloride colorimetric method established by Yusri et al.²⁰ was used to quantify the total flavonoid concentration (TFC) in extracts. TFC was expressed as rutin equivalents in milligrams per gram of extract for extracts (mg RU/g extract).

Fatty acid analysis

A 500 ml of hexane was placed in a flask with a round bottom and 100 g of plant powder was combined with a soxhlet chamber, which was then set up to extract the mixture for 6 hours at 50°C. The distillation procedure was started after the extracts were heated to a gentle extraction temperature of 50°C to prevent thermal degradation of the bioactive components. The solvent and extractor were placed in a water bath after the extraction procedure was finished to allow the solvent to evaporate.  Soxhlet extraction was used to obtain seed oil. Vortex was used to properly homogenize the oil samples and each sample was carefully weighed at 100 mg. Then, 5 mL of methanolic sulfuric acid (12% v/v) and 3 mL of soap methanolic potassium hydroxide (2M) were added to the fat to convert it to methyl ester. One milliliter of regular heptane was used to extract the fatty acid methyl ester, and 1µL of regular heptane phase was added to gas chromatography mass spectro-photometer (GC-MS) (Agilent HP 6890 Series combined with Agilent HP 5973 Mass Selective Detector), to assess the fatty acid profile. By comparing the inhibition times, each fatty acid was identified using the standard fatty acid solution produced by Sigma Company.²¹ 

Statistical analysis

The PROC UNIVARIATE technique of SAS software was used in the current study to verify that all of the data was in accordance with normality before statistical analysis. The means and standard error of the means (SEM) are displayed for each result in the tables. Tukey’s post hoc comparison test was used to explain the analysis of variance (ANOVA) in one way or statistically relevant variations between group means. Statistical operations were carried out with a 95% degree of confidence. The graph was also made using the program Graph Pad Prism 7 (Prism 7.0, Graph Pad Software Inc., CA, USA).

Results and discussion

The antioxidant properties of two plant species, particularly those that are less often used in food and medicine, are currently the subject of a paucity of research data. In light of this, assessing these characteristics is still fascinating and helpful, especially when trying to find new sources of natural polyphenols, food supplements, and health products. ²² To support their activities, all humans needed a variety of complex chemical and inorganic components in their diets. Natural phytochemicals, such as fatty acids, flavonoids, and phenolic compounds, are significant bioactive compounds that have been demonstrated to have a variety of biological effects and to be protective against a number of diseases.

Carbohydrates, lipids, proteins, vitamins, minerals, and water are crucial nutritional components. Table 1 displays the primary nutrient composition of the Celtis tournefortii Lam leaves and fruit, Prosopis farcta pod and seed. The ash contents of the two plant species have similar values, but they differ statistically. The ash content of Celtis tournefortii-fruits Lam’s and leaves 93±0.04% and 3.65±0.08% respectively, is significantly higher than that of the pod and seeds. The higher ash content of the fruits demonstrated their increased mineral richness.²³ Analyses of carbohydrates showed that seeds (48.5±0.28%) had much more carbohydrates than pods (25.8±0.1%), leaves (36.3±0.33%), and fruits. According to Shibata et al.²⁴ the reserve content of Agave angustifolia seeds was primarily made up of starch, with smaller amounts of proteins and lipids. In comparison to seeds (11.80±0.05%), leaves (16.6±0.11%), and fruit (15.4±0.06%), protein levels in pods (20.3±0.05%) were significantly greater. Due to moisture and protein contents often slightly decreasing with maturation and concurrent increases in total carbohydrates and fat, the amount of protein is smaller than the amount of carbohydrates.²⁵ These alterations imply that proteins are being broken down into peptides and amino acids, which can then be employed to create new tissue or contribute to the respiratory cycle of events. According to Shibata et al.²⁴ maturations often resulted in a minor decrease in moisture and protein contents and an increase in total carbs and fat.²⁵ According to Dasari et al.²⁶ environmental factors (such as the year and growing place) have an impact on how much crude protein plants produce as they grow.²⁷

The pod’s (41±0.05 mg/100g) crude fiber content was substantially higher than that of the leaf (36.3±0.11 mg/100g), fruit (32.1±0.02 mg/100g), and seed (28.9±0.05mg/100g). Since non-starchy vegetables are the main sources of dietary fiber utilized in the treatment of conditions like obesity, diabetes, cancer, and gastrointestinal illnesses, traditional medicine practitioners in the Maznie area of Kurdistan region used pods for treating the gastrointestinal tract.³

Table 1: Proximate analysis, total phenol and flavonoid content from leaf, fruit Celtis tournefortii Lam and pod, seed of Prosopis farcta.

The data are expressed as mean ± SEM. Means with different letters were significantly different at the level of P<0.05. SEM, standard error of mean; GAE, gallic acid equivalent; RU, rutin equivalent.

Consuming more dietary fiber was associated with a higher body mass index and a reduced risk of cardiovascular system.²⁸ The 30% of the pulp is made up of dietary fiber, most of which is insoluble. The fiber fraction contains neutral polysaccharides, which make up more than half of it.²⁹ Vitamin C is relatively similar, but statistically, the amount in seeds and pods (25.34±0.0 and 24.01±0.05 mg/100g respectively) was significantly higher than that in leaves and fruits. The ascorbic acid content gradually decreased over time and finally reached its lowest level at the end of the preservation period.  Other essential nutrients include carbohydrates, lipids, proteins, and water.³⁰ Whenever the storage conditions is over, chitosan-treated pepper fruits and plant essential oils reportedly had the greatest vitamin C concentration among treatments and controls. Chitosan can lower O₂ emissions, which can prolong fruit ripening, better preserve vitamin C content, and postpone the aging of sweet peppers since a drop in ascorbic acid content can be closely associated to O₂ content.¹⁷

In the most recent analysis of total sugar, Celtis tournefortii Lam leaves (44.0±0.57 mg/100g) were statistically greater than fruit (41.00±0.57 mg/100g), pod (34.0±0.57 mg/100g), and seed (38.0±0.57 mg/100g). The amount of phenol, the wavelength, and the instrument used all affected the absorbance indices for the sugars with the highest concentration in Celtis tournefortii Lam leaves.³¹ These findings were in line with those made by Mona³² who discovered that spraying rocket (Eruca vesicaria subsp. sativa) with aqueous extracts of Moringa oleifera leaves and twigs at 2% enhanced total sugars and ascorbic acid. Similar to the current study, Deore Sonali ³⁰ revealed that during the summer, total sugar accumulated to high levels in leaves, and that the percentage of total sugar was shown to increase with the number of seeds. It was discovered that the order of the seeds, leaves, stems, and roots corresponded to the concentration of starch. Humans can metabolize some carbs, making them a substantial source of energy.³³

The significance of organic acid analysis has increased as a result of their function in plant physiological activities.³⁴ The outcome demonstrated that total organic acid in fruit (1576±0.57 mg/kg), which was statistically substantially greater than leaf (1543±1.15 mg/kg), pod (1243±0.57 mg/kg), and seed (1376±0.57 mg/kg), was present in larger amounts. According to Pereira et al.³⁵ the Sambucus nigra extract had the highest content of total organic acids (159 mg/g), with the largest contributor being citric acid (97 mg/g), that is in line with observations from Austrian flowers and fruits of this species. Fruit growth occurs simultaneously with the accumulation of sugars and organic acids, but at different developmental stages. In Fagopyrum. esculentum and Hydrangea, the importance of organic acids in the xylem transport, tissue detoxification, and protection of the root apex from stress have been demonstrated.³⁶ Citric acid is in high demand globally due to its minimal toxicity and broad use as an acidulant in the food and health care sectors.³⁷

Plants produce a variety of phytochemicals called phenolic compounds, which are secondary metabolites produced from the amino acids phenylalanine and tyrosine.³⁸ Fruit had a considerably greater total phenolic compound value (52±0.57 mg GAE/100g), compared to the pod (45.98±0.01 mg GAE/100g) and seed (37.90±0.52 mg GAE/100g). In a similar vein, Doshi et al.³⁹ showed that Zanthoxylum armatum fruit methanol extract had a total phenolic compound value of 366.3 mg GAE/g, which was higher than the value of the seeds. Their bark extracts may also significantly contribute to the antioxidant properties, with a presence of 4.39±0.03% and the ability to eliminate free radicals. The domesticated and wild fruits, seeds and bark extracts had varying amounts of total phenolic content. Variations in agronomic techniques, environmental conditions, and genetic origins could also contribute to these disparities.³⁹

Fruits had considerably more total flavonoids (4.39±0.04 mg RU/100g)) than pods (2.31±0.05 mg RU/100g) and seeds (2.34±0.01 mg RU/100g).  Similar to that study, Negi et al.⁴⁰ reported that ethanolic extract Zanthoxylum armatum fruit had 22.8±1.33 mg/kg of total flavonoids, whilst extracts of bark contained 18.33±1.22 mg/g, the amount of flavonoids being considerably less than that of phenol. The polarity of the extraction solvents has an impact on the level of phenols and flavonoids as well. There is a significant relationship between phenolic acid, polyphenols and flavonoids.⁴¹ Flavonoids are recognized to suppress cell development and serve as anticancer agents, and the majority of them are widely accepted as therapeutic medicines.⁴²

Due to their redox-active nature, the great majority of these phytochemicals are regarded as antioxidants. Antioxidant capacities can reduce the consequences of free radicals, reactive oxygen and nitrogen species, which are the primary causes of the majority of chronic diseases. According to the current study, the fruit has a much greater total antioxidant capacity (89.54±0.28%) than leaves (82.50±0.59%), pods (65.00±0.57%), and seeds (67.80±0.86%). According to Tukun et al.⁴³ has the widest variation of total phenol concentration and antioxidant capability. As a result, the nutraceutical food and pharmaceutical industries may greatly benefit from using these plants’ parts that are edible as an amazing source of natural antioxidants. The antioxidant content of the food sample that was consumed does not necessarily correlate with the antioxidant activity that occurs in the target cell. Although Yildrm et al.¹² stated that Celtis Tournefortii Lam had a total antioxidant capacity of 7.09±0.00 mg of fresh fruit; the total antioxidant capacity in fruit in the current investigation was (89.54±0.28%). How bioavailable phytochemical antioxidants are affected by the dietary composition, absorption, and metabolism.⁴⁴ The concentration of antioxidants in any dietary component may differ for a variety of reasons, such as the growing environment, seasonal fluctuations genetically diverse cultivars, storage conditions, and variations in the production and processing procedures.⁴⁵ Similar investigations, however, have proven that the phenolic content of extracts and antioxidant activity are strongly linked.³⁹ An alcoholic extract is prepared from of the fruits, leaves, pods, and seeds of Celtis Tournefortii Lam and Prosopis farcta. Through the use of high-performance liquid chromatography (HPLC), nine polyphenolic substances were identified, including gallic acid, caffeic acid, rutin, coumaric acid, rosmaric acid, cinamic acid, and apigenin as shown in (Table 2). The highest quantity of gallic acid makes up a significant portion of phenolic acids (10.56±0.03 mg/kg). Two catechins, epicatechin gallate and epigallocatechin gallate, are responsible for the high levels of gallic acid released by tannase from green tea preparations.⁴⁶ There are numerous industrial uses for gallic acid and its derivatives, such as supplements or food additives.⁴⁷ Fruit and seeds contained the highest level of caffeine at 12.33±0.16 mg/kg and 12.30 ± 0.10 mg/kg, respectively. Thyme and rosemary contain significant levels of the acids ferulic acid and caffeic acid, claim Wojdyo et al.⁴⁸Although consumers and food manufacturers are familiar with these medicinal plants, there are other, more well-known plants whose extracts can be used as food additives due to their high concentration of numerous pro-health compounds. There isn’t much information in the literature about the amount of chlorogenic acid present in meals and beverages, with the exception is one of the best sources. However, while comparing the chemical makeup of different plants, it is important to take into account elements like climate, seasons, soil, and farming techniques.⁴⁹ Numerous biological characteristics of rutin have been demonstrated, including cytoprotective, antioxidant, and anticancer effects.⁵⁰ According to a certain studies, temperature stress can affect the production of bioactive compounds, which are frequently the basis for the medicinal activity of plants. The primary phenolic components in parsley according to Shan et al. ⁵¹ were apigenin, caffeic acid, p-coumaric acid, and ferulic acid, however, they were unable to find kaempferol. The extraction solvent’s type, polarity and processing  have a considerable impact on the composition of the extract and its total phenolic content.⁵² Pod of Prosopis farcta contained the significantly amount of quercetin with 11.27±0.14 mg/kg than seed 0.43±0.03mg/kg and fruit 0.36± 0.03 mg/kg. Some research has suggested that quercetin may be beneficial for both men and women chronic prostatitis with interstitial cystitis respectively, as a result of its ability to serve as a mast cell inhibitor.⁵³ Quercetin may be effective in treating or preventing respiratory conditions like bronchitis and asthma as well as conditions like cancer, prostatitis, heart disease, cataracts, and allergies/inflammations.⁵² These compounds have been proven to have antioxidant activity.⁵⁴ Yıldırım and his colleagues¹² reported that the antioxidant and polyphenol content of Celtis Tournefortii Lam, which differed from our observations, may be attributed to heredity and environmental factors.

Table 2: Phenolic compound identified by HPLC from leaf, fruit Celtis tournefortii Lam and pod, seed of Prosopis farcta.

Values were expressed as mean ± SEM (n=6). a,b,c Means within a row with different superscript letters are significantly different (p < 0.05) between groups by Tukey’s test.

Leaf, fruit, pod and seed statistical study for fatty acids gas chromatography (GC) were used to identify 15 fatty acids in the Celtis tournefortii and Prosopis farcta showning in (Table 3).  According to Lajnef et al.⁵⁵ six fatty acids were found in the seeds of Prosopis farcta such as palmitic acid, stearic acid, oleic acid, linoleic acid gadoleic acid and lignoceric acids. The Prosopis farcta pods (1.65±0.03%) and Celtis tournefortii fruit (1.54±0.11%) both contain considerably more caprylic acid methyl ester than seeds (0.40±0.05%) and leaves (0.60±0.057%). According to Thakur et al.⁵⁶ study Acacia catechu contains methyl ester forms of caprylic acid (19.77%), lauric acid (27.42%), 2-ethyl-3-methyl-1-butene (42.09%), myristic acid (10.72%), and other acids. Consuming caprylic acid as a dietary supplement, according to some research, can help people lose weight by helping their bodies burn extra calories. A ketogenic diet that includes caprylic acid is also used to treat children with uncontrollable epilepsy. ⁵⁷ According to Lazzara and their colleagues ⁵⁸ the amount of palmitic acid (13.11%) and stearic acid (1.73%) in Ricinus communis leaf extract was measured by gas chromography. However, Prosopis farcta seed had the highest stearic acid content (6.90±0.05%), and Brassica tournefortii leaf and fruit had the highest levels of palmitic acid (17.40±0.05%). Alpha-linolenic acid levels are much greater in fruit (9.60±0.15%) and pods (6.40±0.05%) compared to seeds (0.20±0.05%) and leaves (0.760±0.02%). The usage of flaxseed has been recommended to prevent cardio vascular illness because of its high alpha-linolenic acid content, as demonstrated by Rodriguez-Leyva et al.⁵⁹ Alpha-linolenic acid and omega-3 fatty acid is particularly abundant in flaxseed. Fruit (7.50±0.04%) and leaves (6.70±0.17%) had considerably greater arachidic acid methyl ester levels than pod and seed. Total fatty acids are mainly composed of linoleic acid and arachidic acid, according to Straccia et al.⁶⁰ who also noted that cherry seed oil contains substantial percentages of both of these acids. The amount of eicosenoic acid in seeds (3.20±0.11%) is statistically larger than that in fruit and leaves. Similar to this, Asadi-Samani et al.⁶¹ demonstrated that gamma–linolenic acid, which is consumed as a dietary or food nutritional supplement, is abundant in the plant that produces borage seed oil (26%–38%). There are numerous fatty acids included in it besides seed oil, including linoleic acid (35–38%), oleic acid )16–20%), palmitic acid (10–11%), straric acid (3–4.5%), eicosenoic acid (3–5.5%) and erucic acid (1–3.5%). Multiple sclerosis, diabetes, heart disease, arthritis, and eczema are just a few of the illnesses it is used to treat. Similar to Zayed et al.⁶² who discovered that a maximum of 26 compounds were detected, with n-hexadecanoic acid (44.88%), hexadecanoic acid ethyl ester (17.96%), and octadecanoic acid ethyl ester (11.71%), serving as the principal chemical ingredients of seed and leaf had higher octadecanoic acid ethyl ester levels. The findings led to the conclusion that Neolamarckia cadamba, leaves contain a variety of powerful bioactive chemicals. Similarly, alpha-linolenic acid and docosahexaenoic acid of the walnut extract showed considerable protection against cell death and calcium dysregulation, while linoleic acid and eicosapentaenoic acid did not work as well to protect hippocampus cells from these harms, according to research by Carey et al.⁶³ seed (2.10±0.05%) had significantly higher docosahexaenoic than leaves (1.32±0.0%). The capacity of walnut extract and fatty acids content to shield hippocampus cells from harmful oxidative stress and inflammation’s negative effects.   

According to Alvarez and Rodriguez ⁶⁴ the palmitic, oleic, and linoleic acid composition of the research plants has a remarkable resemblance to industrial lipids utilized in medicinal and cosmetic preparations as well as soybean varieties.⁶⁵ The table showed that saturated fatty acids were greater in the leaf than in the fruit, pod, or seed, but unsaturated fatty acids were higher in the seed than in the pod, fruit, or leaf. Oleic, Cis-11-Eicosenoic, and Cis-4, 7, 10, 13, 16, and 19-Docosahexaenoic were the most common unsaturated fatty acids in the seed, while the two most prevalent saturated fatty acids in the leaf were palmitic and tricosanoic. These outcomes supported the findings of earlier investigations showing the majority of the fatty acids in Prosopis farcta seed oils were unsaturated.⁵⁵

According to several studies ^{(66, 67, 68, 69, 70, 71)}, flavonoids are substances that are found in various plant matrices. According to studies⁷², a cardio protective effect with a 150 mg daily dose⁷³, and a robust improvement of dyslipidemia (reduction of triglycerides, total cholesterol, and low-density lipoprotein cholesterol), are flavonoids in bergamot albedo and juice⁷⁴. Bergamot juice and hazy juice contain the highest representative flavonoids.⁶⁶ For bergamot juice, the Femminello cv was found to contain the highest total amount of flavonoids (520 mg/L), followed by Fantastico (460 mg/L) and Castagnaro (362 mg/L). In our study, total flavonoids in fruits (4.39±0.04 mg RU/100g) is more than in pods (2.31±0.05 mg RU/100g) and in seeds (2.34±0.01 mg RU/100g). Flavonoids are good suppressing agents against cancer cells in humans.

according to⁶⁶ study, epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) were the main tea catechins discovered in dried tea leaves. In addition to those, ready-to-drink products also contained gallocatechin (GC). EGCG accounts for around 40% of the total catechin content and is generally acknowledged as the primary antioxidant component of green tea⁷⁵.

Two Brazilian brands of green tea and a brand of “ban-chá” were previously reported to contain lower amounts of quercetin, ranging from 0.7 to 1.0 mg. 200 mL^-1, with very little kaempferol (0.3 to 0.6) and myricetin present (0.2 to 0.5 mg.200 mL^–1). The Bancha preparation had the lowest catechin concentrations overall, which seems to be consistent with its lowest antioxidant capacity. The greatest amount of total flavonoid was 197 mg. 200 mL^-1 of the Feel Good green tea that is ready to drink, then 145 mg. A Leo tea bag was used to create 200 mL-1 of the infusion. These findings are significant since catechins, a type of antioxidant found in green tea, are largely responsible for the beverage’s positive health effects. It is crucial to let customers know that these levels may differ from one product to another.

The analysis of the fatty acid profile of bergamot seed oil revealed that oleic acid was present in amounts ranging from 30.15% (Castagnaro) to 34.36% (Fantastico), which is comparable to other edible vegetable oils like sesame (36.82–41.75%) and low oleic sunflower (32.47%) or less than other edible vegetable oils like peanut seed oil (44.61%–50.9)⁷⁵. Other citrus seed oils were also found to include oleic acid, which was shown to be present in cold-pressed grapefruit seeds at 20.78% and enzyme-treated grapefruit seeds at 20.74%⁷⁶, and cold-pressed and solvent-extracted lemon seeds at 30.86% and 30.27%, respectively⁷⁷. Linolenic/linolenic acid ratios for Castagnaro, Fantastico, and Femminello were 2.60, 2.15, and 2.97, respectively, whereas linoleic acid levels ranged from 27.01% (Fantastico) to 29.82% (Femminello).

Other authors’ findings on linoleic acid included 39.9% for Citrus sinensis, 42.1% for Citrus nobilis, 26.8% for Citrus limon, var. Interdonato, 44.5% for Citrus limon, var. kütdiken, and 19.5% for Citrus paradise.⁷⁰ Overall, it can be seen that bergamot seed oil has a low total saturated fatty acid content, ranging from 25.85 to 28.78%, while the total unsaturated fatty acid content ranged from 74.15% (Fantastico) to 71.22% (Castagnaro), in amounts that are very similar to those found in tomato seed oil, another vegetable whose seeds could be viewed as a byproduct and not a waste⁶⁸. Fantastico had the greatest oleic/linoleic acid and oleic/palmitic acid ratios, 1.27 and 1.63, respectively. In Castagnaro, Fantastico, and Femminello, respectively, the sum of 18 carbonchain fatty acids accounted for 72.60, 76.13, and 78.13% of the total, whereas polyunsaturated fatty acids (EFAs) made up roughly 40% of each cultivar.

Conclusion

The region of Kurdistan is rich in many plant species and wild vegetables. These plants give the local community both food and medicine. This study is the first to identify various phenolic compounds and fatty acids discovered in two medicinal plants from the Maznie subdistrict in Iraq’s Kurdistan region. A pod has more fiber, protein, and vitamin C, whereas fruit has more organic acid and overall antioxidants. The highest concentration of polyphenols, gallic acid, was identified in the leaf, whereas the highest concentrations of chlorogenic acid, rutin, coumaric, and quercetin were detected in the pod. Oleic, Cis-11-Eicosenoic, and Cis-4, 7, 10, 13, 16, and 19-Docosahexaenoic were the most common unsaturated fatty acids in the seed, while palmitic and tricosanoic were the most prevalent saturated fatty acids in the leaf of Celtis Tournefortii Lam. Despite the fact that Prosopis farcta’s seeds contain saturated fatty acids and its pods contain polyphenols. Therefore, this plant might be more important in preventing a number of serious human ailments. The overall phenolic and flavonoid content is related to this antioxidant activity. Including these plants in daily meals would increase the nutritional value of food while also adding flavor and scent. Future research should focus on isolating and identifying more antioxidants from the plant under study, as well as on their biological activities and associated mechanisms of action.

Table 3: percentage of fatty acids profile from leaf, fruit Celtis tournefortii Lam and pod, seed of Prosopis farcta.

Values were expressed as mean ± SEM (N=3). ^a,b,c Means within a row with different superscript letters are significantly different (p < 0.05) between groups by Tukey’s test.

Acknowledgment

I would like to express my sincere thanks to M. Hedi for assisting to collect plants in the Maznie sub-district. Special appreciation also goes to the M. Mohamad Mirza Agha Mahmood,lab global information system (GIS), scientific research center, from Soran University for providing maps relevant to the study area.

Conflict of Interest

Author states that they have no competing interests. 

Funding sources

The study’s non-financial assistance for the lab work, writing, publication, and/or authorship of this article 

References

1. Saxena M., Saxena J., Nema R., Singh D. Gupta A. Phytochemistry of Medicinal Plants. J pharmacogn. Phytochem. 2013; 1(6):168-182.
2. Ojelere Oo. Phytochemicals, Proximate, Mineral Element Composition and Antimicrobial Activity of Some Selected Medicinal Plant Seeds(Doctoral Dissertation, Department of Chemistry, Faculty of Sciences, University of Ibadan, Ibadan); 2014.
3. Abdulwahid-Kurdi SJ., Abdulwahid MJ., Magaji U., Aghwan ZA., Atan R., Hamadamin KA. Medicinal Plants Used in Soran District Kurdistan Region of Iraq, an Ethnobotanicals Study. J Pharm Pharmacogn Res. 2023; 11(1):1-32.
   CrossRef
4. Anilakumar K. R., Pal A., Khanum F., Bawa A. S. Nutritional, Medicinal and Industrial Uses of Sesame (Sesamum indicum L.) Seeds-an Overview.  Agric Conspec Sci. 2010; 75(4): 159-168.
5. Hashemi SM., Khaneghah AM., Barba FJ., Lorenzo JM., Rahman MS., Amarowicz R., Yousefabad SH., Movahed MD. Characteristics of Wild Pear (Pyrus glabra Boiss) Seed Oil and Its Oil‐in‐Wter Emulsions: A Novel Source of Edible Oil. Eur J Lipid Sci Technol. 2018;120(2):1700284.
   CrossRef
6. Aguiar AC, Cottica SM, Boroski M, Oliveira CC, Bonafé EG, França PB, Souza NE, Visentainer JV. Quantification of Essential Fatty Acids in the Heads of Nile Tilapia (Oreochromis niloticus) Fed with Linseed Oil. J Braz Chem Soc. 2011; 22:643-647.
   CrossRef
7. Batista-Silva W, Nascimento VL, Medeiros DB, Nunes-Nesi A, Ribeiro DM, Zsögön A, Araújo WL. Modifications in Organic Acid Profiles During Fruit Development and Ripening: Correlation or Causation? Front Plant Sci. 2018; 1689 (9):1-20. https://doi.org/10.3389/fpls.2018.01689
   CrossRef
8. Bharati AJ, Bansal YK. Phytochemical Investigation of Natural and in Vitro Raised Vṛddhadāruka Plants. Anc Sci Life. 2014;34(2):80-84.
   CrossRef
9. Mahdi HS. Phytochemical Analysis, Nutritional Value and Ethnobotanical Knowledge of Pelargonium quercetorum AGNEW (Geraniaceae). J Duhok Univ. 2020; 23(2):153-168.
   CrossRef
10. Gurib-Fakim A. Medicinal Plants: Traditions of Yesterday and Drugs of Tomorrow. Mol Aspects Med. 2006; 27(1): 1- 93.
    CrossRef
11. Gecibesler IH. Antioxidant Activity and Phenolic Profile of Turkish Celtis tournefortii. Chem Nat Compd. 2019; 55(4): 738-742.
    CrossRef
12. Yıldırım I., Uğur Y., Kutlu T. Investigation of Antioxidant Activity and Phytochemical Compositions of Celtis tournefortii. Free radic antioxid. 2017; 2017:7(2): 160-165.
    CrossRef
13. Bazzaz FA. Seed Germination in Relation to Salt Concentration in Three Populations of Prosopis farcta. Oecologia, 1973; 13(1): 73-80.
    CrossRef
14. Omidi A, Ghazaghi M. Prosopis farcta Beans Increase HDL Cholesterol and Decrease LDL Cholesterol in Ostriches (Struthio camelus). Trop Anim Health Prod. 2013;45(2):431-4.
    CrossRef
15. Horwitz W., Latimer G. AOAC Official methods of analysis of AOAC International, Gaithersburg, MD, USA. 2005.
16. Brand-Williams W., Cuvelier ME., Berset C. Use of A Free Radical Method to Evaluate Antioxidant Activity. LWT Food Sci Technol. 1995; 28: 25-30.
    CrossRef
17. Mokhtarpour A. R. Z. A., Behrooznam B., Hossein A. A. J. A., Jahromi M. Effect of Chitosan, Salicylic Acid, Malva sylvestris and Aloe vera Extract on Quality Indices of Citrus unshiu During Storage. Int JMech Eng. 2022; 7 (4): 1085- 1094.
18. Hodge JE. Determination of Reducing Sugars and Carbohydrates. Methods Carbohydr Chem (1962): 1; 380-394.
19. Iqbal S., Bhanger MI. Effect of Season and Production Location On Antioxidant Activity of Moringa oleifera Leaves Grown in Pakistan. J Food Compost Anal. 2006; 19(6-7): 544-551.
    CrossRef
20. Yusri NM., Chan KW., Iqbal S., Ismail M. Phenolic content and antioxidant activity of Hibiscus cannabinus Seed Extracts After Sequential Solvent Extraction. Mol. 2012; 17(11): 12612-12621.
    CrossRef
21. Saadatian M., Mohammad RH., Jumaah AA., Oagaz JA. Evaluation of Nutritional Value, Fatty Acids and Polyphenols Profiles of Pyrus amygdaliformis Grown in North-East Kurdistan Regional Government, Iraq. Journal of Oleo Science. 2022; 71(7): 985-990.
    CrossRef
22. Sofowora A. Research On Medicinal Plants and Traditional Medicine in Africa. J Altern Complement Med. 1996; 2(3): 365-372.
    CrossRef
23. Kalsum HU., Mirfat HS. Proximate Composition of Malaysian Underutilised Fruits. J Trop Agric and Fd. 2014; 42(1): 63-72.
24. Shibata M., Coelho CMM., Steiner N., Block JM., Maraschin M. Lipid, Protein and Carbohydrate During Seed Development in Araucaria angustifólia. Cerne. 2020; 26: 301-309.
    CrossRef
25. Harden ML., Zolfaghari R. Nutritive Composition of Green and Ripe Pods of Honey Mesquite (Prosopis glandulosa, Fabaceae). EconBot.1988;42(4): 522-532.
    CrossRef
26. Dasari R., Sathyavati D., Belide SK., Reddy P., Abbulu K. Evaluatıon of Antıoxıdant Actıvıty of Two Important Memory Enhancıng Medıcınal Plants Celtıs tımorensıs and Vanda spathulata. Asian J Pharm Clin Res. 2013;6(2):153-155.
27. Bárta J., Kalinová J., Moudrý J., Čurn V. Effects of Environmental Factors On Protein Content and Composition in Buckwheat Flour. Cereal Res Commun. 2004; 32(4): 541-548.
    CrossRef
28. Liu S., Buring J. E., Sesso, H. D., Rimm, E. B., Willett, W. C., Manson, J. E. A Prospective Study of Dietary Fiber Intake and Risk of Cardiovascular Disease Among Women. J Am Coll Cardiol. 2002; 39(1):  49-56.
    CrossRef
29. Bravo L, Grados N., Saura-Calixto F. Composition And Potential Uses Of Mesquite Pods (Prosopis pallida L) Comparison With Carob Pods (Ceratonia siliqua L). J Sci Food Agric.1994; 65 :303-306.
    CrossRef
30. Deore Sonali V. Estimation of Total Carbohydrates.  Int J Pharm Nat Med. 2016; 4(2): 72-75.
31. Buysse J. A. N., Merckx R. (1993). An Improved Colorimetric Method to Quantify Sugar Content of Plant Tissue. J Exp Bot. 1993; 44(10): 1627-1629.
    CrossRef
32. Mona MA. The Potential of Moringa oleifera Extract as A Biostimulant in Enhancing the Growth, Biochemical and Hormonal Contents in Rocket (Eruca vesicaria sativa) Plants. Int J Plant Physiol Biochem. 2013;5(3):42-9.
    CrossRef
33. Saucedo M. C. C., Alvarado A. D., Téllez L. C., Hernández V. G., Tapia-Campos E., VarelaA. S., García-De Los Santos G. Changes in Carbohydrate Concentration in Leaves, Pods and Seeds of Dry Bean Plants Under Drought Stress. Interciencia. 2012; 37(3): 168-175.
34. Bennet-Clark TA. The Role of the Organic Acids in Plant Metabolism Part I. New Phytol. 1993: 32(1); 37-71.
    CrossRef
35. Pereira C., Barros L., Carvalho A. M., Ferreira I. C. (2013). Use of UFLC-PDA for The Analysis of Organic Acids in Thirty-Five Species of Food and Medicinal Plants. Food Anal. 2013; 6(5): 1337-1344.
    CrossRef
36. Arnetoli M., Montegrossi G., Buccianti A., Gonnelli, C. (2008). Determination of Organic Acids in Plants of Silene paradoxa by HPLC. J Agric Food Chem. 2008; 56(3): 789-795.
    CrossRef
37. Anastassiadis S, Morgunov I.G, Kamzolova S.V, Finogenova T.V. Citric Acid Production Patent Review. Recent Pat Biotechnol. 2008; 2(2):107–123.
    CrossRef
38. Saeed N., Khan M. R., Shabbir M. Antioxidant Activity, Total Phenolic and Total Flavonoid Contents of Whole Plant Extracts Torilis leptophyllaBMC Complement Altern Med. 2012; 12(1): 1-12.
    CrossRef
39. Doshi P., Adsule P., Banerjee K. Phenolic Composition and Antioxidant Activity in Grapevine Parts and Berries (Vitis vinifera) cv. Kishmish Chornyi (Sharad Seedless) During Maturation. Int J Food Sci Technol. 2006; 41(1): 1–9.
    CrossRef
40. Negi J. S., Bisht V.K., Bhandari A.K., Singh P., Sundriyah R.C. Chemical Constituents and Biological Activities of the Genus Zanthoxylum: A Review. Afr J Pure Appl2011; 5(12): 412–416.
41. Akinola A. A., Ahmad S., Maziah M. Total Anti-Oxidant Capacity, Flavonoid, Phenolic Acid and Polyphenol Content in Ten Selected Species of Zingiberaceae Rhizomes.  Afr J Tradit. Complement Altern. 2014; 11(3): 7-13.
    CrossRef
42. Silalahi M., Nisyawati N, Pandiangan D. Medicinal plants used by the Batak Toba Tribe in Peadundung Village, North Sumatra, Indonesia. Biodiver J Biol Biodivers. 2019;20(2):510-525.
    CrossRef
43. Tukun A. B., Shaheen N., Banu C. P., Mohiduzzaman M. D., Islam S., Begum M. Antioxidant Capacity and Total Phenolic Contents in Hydrophilic Extracts of Selected Bangladeshi Medicinal Plants. Asian Pac J Trop  2014; 7:  S568-S573.
    CrossRef
44. Manach C, Williamson G, Morand C, Scalbert A, Remesy C. Bioavailability and Bioefficacy of Polyphenols in Humans. I. Review of 97 Bioavailability Studies. Am J Clin Nutr. 2005, 81: 230S-242S.
    CrossRef
45. Carlsen M. H., Halvorsen B. L., Holte K., Bøhn S. K., Dragland S., Sampson L., Blomhoff R. The Total Antioxidant Content of More Than 3100 Foods, Beverages, Spices, Herbs and Supplements Used Worldwide. Nutr J. 2010; 9(1): 1-11.
    CrossRef
46. Gramza A., Korczak J., Amarowicz R., Tea Polyphenols – Their Antioxidant Properties and Biological Activity – A Review. Pol J Food Nutr Sci. 2005; 14(55): 219–235.
47. Yang K., Zhang L., Liao P., Xiao Z., Zhang F., Sindaye D., Deng B. Impact of Gallic Acid on Gut Health: Focus On the Gut Microbiome, Immune Response, And Mechanisms of Action. Front Immunol. 2020; 11(580208): 1-13.
    CrossRef
48. Wojdyło A., Oszmiański J., Czemerys R. Antioxidant Activity and Phenolic Compounds in 32 Selected Herbs. Food Chem.2007; 105, 940–949.
    CrossRef
49. Marques V., Farah A. (2009). Chlorogenic Acids and Related Compounds in Medicinal Plants and Infusions. Food Chemistry. 2009; 113(4): 1370-1376.
    CrossRef
50. Enogieru A. B., Haylett W., Hiss D. C., Bardien S., Ekpo O. E. Rutin as A Potent Antioxidant: Implications for Neurodegenerative Disorders. Oxid Med Cell Longev. 2018; 6241017: 1-17.
    CrossRef
51. Shan B., Cai Y.Z., Sun M., Corke H. Antioxidant Capacity of 26 Spice Extracts and Characterization of Their Phenolic Constituents. J Agric Food Chem. 2005; 53 (20): 7749–7759
    CrossRef
52. Sharma P., Roy B., Roy M., Sundarrao G S. Citrus: A Need for Its Conservation in Utilising Its Medicinal Values Through Biotechnological Tools. Int J Curr Microbiol App Sci. 2020; 9(6): 3825-3834.
    CrossRef
53. Bischoff S.C. Quercetin: potentials in the prevention and therapy of disease. Curr Opin Clin Nutr Metab Care. 2008; 11(6): 733-740.
    CrossRef
54. Meyer A. S., Donovan J. L., Pearson D. A., Waterhouse A. I., Frankel E. N. Fruit Hydroxycinnamic Acids Inhibit Human Low-Density Lipoprotein Oxidation in Vitro. J Agric Food Chem. 1998; 46 (5): 1783-1787.
    CrossRef
55. Lajnef H. B., Mejri H., Feriani A., Khemiri S., Saadaoui E., Nasri N., Tlili, N. Prosopis farcta Seeds: Potential Source of Protein and Unsaturated Fatty Acids? J Am Oil Chem Soc. 2005; 92(7): 1043-1050.
    CrossRef
56. Thakur AV, Ambwani S, Ambwani TK. Preliminary Phytochemical Screening and GC-MS Analysis of Leaf Extract of Acacia catechu (Lf) Willd. Int J Herb Med. 2018; 6(2):81-85.
57. Mungali M., Tripathi A., Singhal S. Valeriana officinalis (valerian). Belwal T., Nabawi S. M., Nabavi S., Dehpour A., Shirooie S. In Naturally Occurring Chemicals Against Alzheimer’s Disease. Academic Press. 2021; 283-291.
    CrossRef
58. Lazzara R, Fernandes D, Faria M, López JF, Tauler R, Porte C. Changes in Lipid Content and Fatty Acid Composition Along the Reproductive Cycle Of The Freshwater Mussel Dreissena polymorpha: Its Modulation By Clofibrate Exposure. Sci Total Environ.2012; 15 (432):195-201.
    CrossRef
59. Rodriguez-Leyva D., Bassett C. M., McCullough R., Pierce G. N. The Cardiovascular Effects of Flaxseed and Its Omega-3 Fatty Acid, Alpha-Linolenic Acid. Can J Cardiol.2010; 26(9): 489-496.
    CrossRef
60. Straccia M. C., Siano F., Coppola R., La Cara F., Volpe M. G. (2012). Extraction and Characterization of Vegetable Oils from Cherry Seed By Different Extraction Processes. Chem Eng g Trans. 2012; 27: 391-396.
61. Asadi-Samani, M., Bahmani, M., Rafieian-Kopaei M. The Chemical Composition, Botanical Characteristic and Biological Activities of Borago officinalis: a review. Asian PacJ Trop Med. 2014; 7 (1):  S22-S28.
    CrossRef
62. Zayed M. Z., Ahmad F. B., Ho W. S., Pang, S. L. GC-MS Analysis of Phytochemical Constituents in Leaf Extracts of Neolamarckia cadamba (Rubiaceae) from Malaysia. Int J Pharm Pharm Sci. 2014; 6(9): 123-127.
63. Carey A. N., Fisher D. R., Joseph J. A., Shukitt-Hale B. The Ability of Walnut Extract and Fatty Acids to Protect Against the Deleterious Effects of Oxidative Stress and Inflammation In Hippocampal Cells. NutrNeurosci. 2013; 16(1): 13-20.
    CrossRef
64. Alvarez R. AM, Rodríguez G. M. L. Lipids in Pharmaceutical and Cosmetic Preparations. Grasas y Aceites. 2000; 51 (1-2): 74-96.
    CrossRef
65. Gulluoglu L, Bakal H, Arioglu H. Oil content and composition of soybean genotypes grown in different growing seasons under Mediterranean conditions. J Environ 2018; 39(2):211-215.
    CrossRef
66. Kodama D.H, Gonçalves A.E, Lajolo F.M, Genovese M.I. Flavonoids, total phenolics and antioxidant capacity: comparison between commercial green tea preparations. Food Sci Technol. 2010;  30 (4): 1077-1082 https://doi.org/10.1590/S0101-20612010000400037
    CrossRef
67. Maria G. A, Riccardo N. Citrus bergamia, Risso: the peel, the juice and the seed oil of the bergamot fruit of Reggio Calabria (South Italy). Emir J Food Agric. 2020; 32(7): 522-532. DOI: 10.9755/ejfa.2020.v32.i7.2128
    CrossRef
68. Giuffrè, A. M. 2013. HPLC-DAD detection of changes in phenol content of red berry skins during grape ripening. Eur Food Res Technol. 2013; 237: 555-564.
    CrossRef
69. Sidari R. A, Martorana A.M, Giuffrè M. Capocasale C, Zappia. Sourdoughs as a source of lactic acid Bacteria and yeasts with technological characteristics useful for improved bakery products. Eur Food Res Technol. 2018; 244: 1873-1885.
    CrossRef
70. Panuccio MR, Papalia T, Attinà E, Giuffrè A, Muscolo. Use of digestate as an alternative to mineral fertilizer: Effects on growth and crop quality. Arch Agron Soil Sci. 2019; 65(5): 700-711.
    CrossRef
71. Fiorillo M, Peiris-Pagès M, Sanchez-Alvarez R, Bartella L, Di Donna L, Dolce V, Sindona G, Sotgia F, Cappello AR, Lisanti MP. Bergamot natural products eradicate cancer stem cells (CSCs) by targeting mevalonate, Rho-GDI-signalling and mitochondrial metabolism. BBA-Bioenergetics. 2018;1859(9):984-996.
    CrossRef
72. Navarra M, Ursino MR, Ferlazzo N, Russo M, Schumacher U, Valentiner U. Effect of Citrus bergamia juice on human neuroblastoma cells in vitro and in metastatic xenograft models. Fitoterapia. 2014; 95:83-92.
    CrossRef
73. Toth PP, Patti AM, Nikolic D, Giglio RV, Castellino G, Biancucci T, Geraci F, David S, Montalto G, Rizvi A, Rizzo M. Bergamot reduces plasma lipids, atherogenic small dense LDL, and subclinical atherosclerosis in subjects with moderate hypercholesterolemia: a 6 months prospective study. Pharmacol. 2016: 6(299); 1- 9. https://doi.org/10.3389/fphar.2015.00299
    CrossRef
74. Russo M, Dugo P, Marzocco S, Inferrera V, Mondello L. Multidimensional preparative liquid chromatography to isolate flavonoids from bergamot juice and evaluation of their anti‐inflammatory potential. J Sep Sci. 38(24):4196-203.
    CrossRef
75. Seeran, N. P. et al. Catechin and caffeine content of green tea dietary supplements and correlation with antioxidant capacity. J AgricFood Chem. 2006: 54 (5);1599-1603.
    CrossRef
76. Yilmaz E, Aydeniz Guneser B, Ok S. Valorization of grapefruit seeds: cold press oil production. Waste and Biomass Valorization. 2019:10; 2713-2724.
    CrossRef
77. Yilmaz E, Güneser BA. Cold pressed versus solvent extracted lemon (Citrus limon) seed oils: Yield and properties. J Food Sci Technol. 2017: 54; 1891-1900.
    CrossRef