MEDICINAL GINGER (Zingiber officinale) ROOT: ISOLATION AND COMPARISON OF THE BIOLOGICALLY ACTIVE COMPOUND 6-GINGEROL USING VARIOUS METHODS

ABSTRACT

Gingerol, the primary bioactive compound in (Zingiber officinale Roscoe), exhibits potent anti-inflammatory, antioxidant, and anticancer properties. Efficient extraction of gingerol is crucial for its application in nutraceuticals and pharmaceuticals. This study investigates the extraction efficiency of gingerol using three different methods: Soxhlet extraction, ultrasonic-assisted extraction, and conventional solvent mixing. (Zingiber officinale Roscoe) rhizomes were dried, powdered, and subjected to extraction under optimized conditions for each method. The extracted gingerol content was quantitatively analyzed using High-Performance Liquid Chromatography (HPLC). Results demonstrated that Soxhlet extraction for 8 hours yielded the highest gingerol content (3.43%), while ultrasonic-assisted and conventional mixing methods produced lower yields of 2.17% and 1.56%, respectively. The findings indicate that Soxhlet extraction provides superior efficiency for gingerol isolation, which can facilitate further pharmacological and nutraceutical applications. This study provides a comparative assessment of extraction methods, contributing valuable information for the optimization of gingerol recovery from (Zingiber officinale)

АННОТАЦИЯ

Гингерол, основное биоактивное соединение в (Zingiber officinale Roscoe), обладает мощными противовоспалительными, антиоксидантными и противораковыми свойствами. Эффективная экстракция гингерола имеет решающее значение для его применения в нутрицевтике и фармацевтике. В данном исследовании изучалась эффективность экстракции гингерола с использованием трех различных методов: экстракции по Сокслету, ультразвуковой экстракции и традиционного смешивания растворителей.

Корневища (Zingiber officinale Roscoe) были высушены, измельчены в порошок и подвергнуты экстракции в оптимизированных условиях для каждого метода. Содержание экстрагированного гингерола было количественно проанализировано с помощью высокоэффективной жидкостной хроматографии (ВЭЖХ). Результаты показали, что экстракция по.Сокслету в течение 8 часов дала наибольшее содержание гингерола (3,43%), в то время как ультразвуковая экстракция и традиционный метод смешивания дали более низкие выходы — 2,17% и 1,56% соответственно. Полученные результаты показывают, что экстракция по Сокслету обеспечивает более высокую эффективность выделения гингерола, что может способствовать его дальнейшему применению в фармакологии и нутрицевтике. Данное исследование представляет собой сравнительную оценку методов экстракции, предоставляя ценную информацию для оптимизации извлечения гингерола из (Zingiber officinale).

Keywords: (Zingiber officinale); 6-gingerol; bioactive compounds; Soxhlet extraction; ultrasound-assisted extraction; maceration; pharmacological analysis; antioxidant.

Ключевые слова: (Zingiber officinale); 6-гингерол; биоактивные соединения; экстракция по Сокслету; экстракция с помощью ультразвука; мацерация; фармакологический анализ; антиоксидант.

Introduction

Ginger (Zingiber officinale Roscoe) has been widely used since ancient times as a medicinal plant in both traditional and modern pharmacology. Its rhizome is rich in bioactive phenolic compounds, among which gingerol, shogaol, paradol, and zingerone are of particular scientific importance. Gingerol, especially found in red ginger, serves pharmaceutical purposes as an analgesic agent. The conventional method for gingerol extraction is the Soxhlet method; however, this approach is limited by its lengthy process and low yield. Therefore, this study investigated the effect of ultrasonic frequency on enhancing gingerol yield. During the extraction process, 70% ethanol was used as the solvent at 50 °C, and the results were analyzed using HPLC. The study demonstrated that ultrasonic treatment at 50 kHz for 120 minutes produced the highest gingerol yield of 24.71%. [1,p. 4-5].

Red ginger (Zingiber officinale var. Rubrum) extract was encapsulated with maltodextrin and Arabic gum in various ratios, and the 10‑gingerol content of each formulation was quantified using high-performance liquid chromatography (HPLC). The results showed that all encapsulated extracts retained measurable amounts of 10‑gingerol, with the highest concentration of 74.99 ppm observed in the 2:1:1 extract:maltodextrin:Arabic gum formulation. These findings indicate that gingerol remains stable and pharmacologically active even after heat processing and encapsulation, while the encapsulation ratio significantly affects its concentration, which is relevant for pharmaceutical and nutraceutical applications [2 ,p.154-162].

High-Performance Liquid Chromatography (HPLC) has been effectively applied to assess the stability of 6‑gingerol in ginger extracts under varying conditions. The study demonstrated that 6‑gingerol degradation is highly pH-dependent, with maximum stability observed at pH 4, whereas extreme acidic conditions (pH 1) and high temperature (100 °C) accelerate its reversible breakdown, reaching equilibrium in less than two hours. HPLC analysis confirmed that 6‑gingerol remains detectable and quantifiable in different formulations, providing a reliable approach to monitor ginger extract stability and supporting its use in pharmaceutical and nutraceutical product development [3,p.55-60].

6‑Gingerol, the primary bioactive compound in ginger (Zingiber officinale) rhizomes, plays a central role in its use across food, cosmetic, and pharmaceutical applications. To achieve high purity, multiple extraction and purification techniques have been explored. Both conventional methods, such as solvent extraction using hydroalcoholic solutions, and non-conventional methods, including liquid CO₂ extraction, are effective, but microwave-assisted extraction has been identified as the most efficient approach for maximizing 6‑gingerol yield. These strategies not only enhance the isolation of 6‑gingerol but also improve its bioavailability in functional products [4,p.67-83].

A validated HPLC method was used to quantify 6‑gingerol in ginger extracts, showing high accuracy and precision. Green solvents, such as glycerin-ethanol and natural deep eutectic mixtures, efficiently extracted 6‑gingerol, and microwave-assisted extraction enhanced yield, supporting eco-friendly preparation of functional ginger products [5,p.851-857].

Ginger (Zingiber officinale) exhibits a wide range of therapeutic effects, including relief from indigestion, stomach ulcers, arthritis, rheumatism, atherosclerosis, hypertension, diabetes, vomiting, and cancer, largely attributed to its bioactive phenolic compounds [6,p.10-12].

Various extraction methods have been developed to obtain bioactive compounds from ginger, ranging from traditional Soxhlet extraction to modern techniques such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and supercritical fluid extraction (SFE) [7,p.427-430 ] Soxhlet extraction continues to be widely employed for its reproducibility and reliability, though it requires longer processing times and larger volumes of solvents [9,p.1654-1656]. In contrast, UAE has gained significant attention as a green and efficient method; ultrasonic waves create cavitation bubbles in the solvent, which collapse and enhance mass transfer, leading to higher extraction yields in shorter durations while preserving the integrity of sensitive compounds [8,p.542-545][11 artecl no,pdf 5-7.].

Microwave-assisted extraction uses targeted heating of both the plant matrix and solvent, accelerating compound release and reducing overall extraction time [10,p.227-250]. SFE and other advanced methods offer additional benefits, including minimized solvent usage and enhanced selectivity for specific bioactive molecules [7,p.427-430][9,p.1654-1656]. Furthermore, post-extraction processing, such as convective hot air drying, can influence the stability and recovery of phenolic compounds, underscoring the importance of optimizing process parameters to maintain bioactivity [12,p.3897-3909]. Following extraction, purification of gingerol is typically achieved using chromatographic techniques such as column chromatography and high-performance liquid chromatography (HPLC), which allow separation based on polarity and molecular interactions [13,p.1671-1685] Structural characterization of isolated compounds is commonly performed using spectroscopic techniques such as Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and mass spectrometry (MS) [14,p.598]. FTIR analysis enables the identification of key functional groups such as hydroxyl (–OH), carbonyl (C=O), and aromatic structures, which are characteristic for gingerol and confirm its presence [15.p.302]. Several studies have confirmed that ginger extracts exhibit strong antioxidant activity by scavenging free radicals and reducing oxidative stress [16,p.1117-1125]. Additionally, gingerol has been reported to inhibit inflammatory pathways, including cyclooxygenase (COX) and lipoxygenase (LOX), contributing to its anti-inflammatory effects [17,p.s38-s39]. Recent research has focused on optimizing extraction conditions and developing novel formulations to enhance the bioavailability and stability of gingerol and shogaol [18,p.40-41]. These advancements have expanded their potential applications in drug development and functional food production [18,p. 40-41]. Therefore, the main aim of the present study was to compare the efficiency of obtaining gingerol from ginger root using three methods Soxhlet extraction, ultrasound-assisted extraction, and solvent-based mechanical stirring by HPLC analysis

MATERIALS AND METHODS

The object of this study is the biologically active components of medicinal ginger (Zingiber officinale Roscoe) root, specifically the compounds gingerol and shogaol. The research focuses primarily on the isolation and purification of these compounds, as well as the investigation of their physicochemical properties.

The subject of the study is the efficiency of isolating gingerol and shogaol compounds using different extraction methods Soxhlet extraction, ultrasound-assisted extraction, and simple stirring as well as the pharmacological potential of the obtained extracts and the quality variations depending on extraction conditions. Additionally, the results are aimed at evaluating the potential application of medicinal ginger as a source of biologically active supplements and at identifying opportunities for more effective use in pharmaceutical and other purposes.

25 grams ginger root was dried at 45°C for 24 hours. The dried roots were ground in a laboratory mill (LMT-1, Russia) to a particle size of 1–2 mm. Ten grams of the ground powder were placed into a Soxhlet apparatus, an ultrasonic bath, or a flask for simple stirring. Before extraction, the samples were maintained under a flow of inert nitrogen for 10 minutes to prevent oxidation.

The roots of medicinal ginger (Zingiber officinale Roscoe) were selected as the research material. The roots, obtained from a local market (Shandong variety), were dried in a ventilated oven (VWR Dry-Line 53, Germany, 2016) at 50–60°C and subsequently ground into small pieces measuring 40–60 mm.

Three extraction methods were employed to isolate biologically active compounds: Soxhlet extraction, ultrasound-assisted extraction, and simple stirring (maceration). These methods were carried out according to the procedures previously described in the literature [3,p.55-60–5, p.851-857]. Soxhlet extraction was used as the standard method for the isolation of gingerol and shogaol [3,p. 55-60].

The solvent used was 250 mL of 96% ethanol, with an extraction temperature of 55–60°C and an extraction time of 4–8 hours. The number of cycles was 24–26, and the condenser temperature was maintained at 10–13° C.Ethanol is more polar than acetone, making it well-suited for the phenolic portion of gingerol. Since the ethanol was anhydrous, it does not hydrolyze gingerol. The relatively high boiling temperature allows for deeper extraction.This extraction process was carried out for 4 hours using 10 g of the sampleThe ground ginger root (FAITHFUL, FA2204N, China) was placed in a Soxhlet apparatus and extracted for 8 hours with 150 mL of ethanol:ethyl acetate (7:3) solvent. The obtained extract was concentrated and purified using column chromatography. This method provides a high concentration of the extract and enables effective isolation of bioactive components. The extract was filtered and concentrated using a rotary evaporator.

Soxhlet Acetone Extraction of Gingerol.In this method, extraction was carried out using two different solvents. 250 mL of acetone (analytical grade, 96%) was used, with an extraction temperature of 55–60°C and an extraction time of 4–8 hours. The number of cycles was 24–26, and the condenser temperature was maintained at 10–13°C. In this method, only the solvent was changed; the procedure and duration remained the same. The extract was filtered and concentrated using a rotary evaporator.

Ultrasonic Assisted Extraction (UAE) Ultrasonic extraction was applied as a rapid and efficient method [4,p.67-83].Key parameters of the UAE method: frequency (35–40 kHz), power (250–350 W), temperature (25–55°C), and time (15–60 minutes). Five grams of ground ginger root were treated in 100 mL of ethanol in an ultrasonic bath (GT SONIC, China) for 30 minutes. The extract was filtered and concentrated using a rotary evaporator.

Ultrasonic extraction is a modern, highly efficient, and energy-saving method for isolating bioactive compounds from plants. In recent years, it has been widely used to accelerate the diffusion of phenolic components, including gingerols. Ultrasonic waves induce cavitation in the liquid at high frequency, microbubbles are formed and their collapse results in cell wall disruption, facilitating the transfer of intracellular gingerol into the external solvent and significantly reducing the extraction time (10–15 times shorter compared to Soxhlet extraction).Ultrasonic-Assisted Extraction (UAE) Using a Medium-Polar Solvent Ethyl Acetate Parameters: Solvent: 100 mL ethyl acetate, Frequency: 40 kHz,Power: 280 W,Temperature: 35°C, Extraction time: 20 minutes,Sonication mode: Continuous,Ethyl acetate is less polar than ethanol, so its interaction with the gingerol molecule differs. The scientific basis of the process is as follows: Ethyl acetate exhibits higher selectivity toward phenolic compounds, and its lower boiling point enhances cavitation during UAE. Cavitation in ethyl acetate is stronger (approximately 4 times stronger than in water), which accelerates the release of gingerol from the cells.

Simple Stirring (Maceration).The simple stirring method (maceration) has also been recommended in the literature [5,p.851-857]. Ground ginger root was stirred in a solvent at room temperature for 24 hours. The extract was then filtered and concentrated using a rotary evaporator.

This method is practically the least expensive and allows the isolation of bioactive components over an extended period. Since gingerol is a thermally sensitive compound (it can convert to shogaol above 45–60°C), maceration extraction is considered a very suitable method for isolating it without disrupting its natural structure. In this section, the isolation of gingerol by simple stirring using two different solvents ethanol and acetone is described with extensive scientific justification. Solvent: 70% ethanol Solvent volume:200mL,Rawmaterial mass:5gStirring speed: 350 rpm Temperature: 25°C (room temperature)Time: 24 hours (for complete diffusion) Stirring type: Magnetic stirrer continuous The 70% ethanol (water ethanol system) is ideal for gingerol, as its phenolic part interacts well with water, while the hydrocarbon chain interacts effectively with ethanol.

In the ethanol water mixture, pectin, cellulose, and hemicellulose in the cell walls partially swell. This expands the diffusion pathway, facilitating the transfer of gingerol into the solvent. Over 24 hours, the concentration gradient stabilizes. Stirring increases the molecular kinetic energy in the system. The high polarity of ethanol provides effective solvation of the phenolic OH groups of gingerol. After filtration and vacuum evaporation of the solvent, 40 mL of concentrated extract, which had undergone purification steps, was obtained.Scientific mechanism of the process: Ethanol forms strong sigma bonds with phenolic compounds, enhancing extraction efficiency. The extract was filtered and concentrated using a rotary evaporator.

Column Chromatography (CC): Silica gel 60–120 mesh was used, and an n-hexane:ethyl acetate (7:3) solvent system was applied for elution [6,p.10-12]. This method ensures high purity of the isolated compounds. (TLC): The purity and identification of the isolated compounds were checked using TLC: FTIR (SHIMADZU IRSpirit JAPAN) spectra were recorded to determine the functional groups of gingerol and shogaol [8,p.542-545]. This identification serves to confirm the structural characteristics of the compounds. Each extraction method was repeated at least three times, and the results were expressed as mean values.

 The purity and identification of the extracts were continuously monitored using TLC and FTIR. All solvents and apparatus were used under sterile and clean conditions, and experimental conditions were consistently maintained. This procedure aimed to ensure the reproducibility of the study and the reliability of the results.YUSSC-metodi. This method is based on the detection of 6-gingerol using reverse-phase high-performance liquid chromatography (RP-HPLC). The 6-gingerol molecule exhibits strong UV absorption in the range of 280–285 nm, is separated on a C18 column, and quantitatively determined via a UV detector.

The method allows precise separation of gingerol from other phenolic compounds (6-shogaol, zingerone, and others). 6-Gingerol standard sample CAS number 23513-14-6 (≥98% purity), Methanol (HPLC grade), Acetonitrile (HPLC grade), Distilled water (0.22 µm filtered), 0.45 µm membrane filter,Ginger extract sample. HPLC system (with UV detector), C18 column (250 × 4.6 mm, 5 µm), Ultrasonic bath, Column: C18, 250 × 4.6 mm, 5 µm, Mobile phase: acetonitrile:water (70:30), Flow rate: 1.0 ml/min, Detection wavelength: 282 nm, Injection volume: 20 µl, Column temperature: 30 °C, Analysis time: 10–15 minutes, Retention time: in the range of 6–8 minutes.Sample preparation for analysis: 50 mg of dried extract is weighed. It is dissolved in 10 ml of methanol and treated in an ultrasonic bath for 10 minutes. The solution is passed through a 0.45 µm filter. A 20 µl aliquot is injected into the HPLC system.

The method for the identification of 6-gingerol by FTIR spectroscopy: FTIR spectrometer is used, and purified 6-gingerol powder is obtained. A 1–2 mg sample is placed on the ATR crystal surface. The device is closed, and the spectrum is recorded. Each sample is analyzed three times. Spectra are recorded in the range of 4000–400 cm⁻¹.

Purification of gingerol using column chromatography. Column chromatography is a separation method based on the polarity, molecular weight, and interaction of organic compounds with the adsorbent. This method is widely used for the purification of bioactive phenolic compounds such as gingerol because it provides high selectivity and control [1,p. 4-5].

If the extract is liquid, dissolve it in a small amount of n-hexane or ethyl acetate to form a suspension. If necessary, the extract can be pre-adsorbed on silica gel, which facilitates uniform distribution of the sample on the column.

Slowly apply the extract to the column, taking care not to disturb the top layer. Since gingerol is a moderately polar phenolic compound, an n-hexane:ethyl acetate mixture (8:2 or 7:3) was used initially.

During separation, the polar portion of the eluent can be gradually increased (gradient elution) for example, up to n-hexane:ethyl acetate 5:5.

RESULTS AND DISCUSSION.

The mass fraction of gingerol was 3.2% (higher in acetone). Using the same method with ethanol as the solvent, and by extending the extraction time to 8 hours, 30 ml of extract was obtained. When analyzed by YUSSC, the presence of gingerol was found to be 3.43%, which is considered a good yield. The total content of gingerol in this extract was 1.321% (according to HPLC analysis). Extending the extraction time to 8 hours using the same method and quantities improved the result, yielding 2.84% gingerol.

General scientific analysis of Soxhlet extraction. Ethanol extracted ahigher amount of gingerol. Acetone, at low temperature, extracted fewer pigments, resulting in a cleaner extract. The results of soxhlet extraction are presented in (Tabl-1)

Table 1.

Results of soxhlet extraction

GINGEROL ISOLATIONBY ULTRASONIC BATH (UAE) After 1 hour of UAE, ethanol was evaporated, and 40 ml of concentrated extract was obtained. According to HPLC results, the mass fraction of gingerol was 1.54%. With a 60-minute UAE, 40 ml of concentrated purified extract contained 1.46% 6-gingerol. Using acetone as a solvent, 40 ml of concentrated extract yielded 1.12% and 1.24% gingerol. The result ultrasonic exstraction are presented (Table-2)

Table 2.

Result ultrasonic exstraction

Maceration gingerol isolation in ethanol Results Extraction was carried out using different solvents, ethanol and acetone, over 24 and 12 hours, and the extract concentration gradient stabilized.YUSSC analysis showed gingerol content: 0.142%. This is lower than Soxhlet-ethanol extraction but is typical for the maceration method.

Conditions: Solvent: 96% ethanol,Solvent volume: 200 mL,Stirring rate: 400 rpm,Temperature: 30 °C,Extraction time: 12 hours, Raw material: 10 g.

Due to ethanol’s high diffusion capacity, the extraction time was set to 12 hours; extending to 24 hours may lead to partial oxidation of gingerol.

VGH analysis showed gingerol content: 1.064%. This is lower than Soxhlet-ethanol extraction but is normal for maceration. During the conducted studies, Soxhlet extraction, ultrasonic-assisted extraction (UAE), and maceration methods were applied for the isolation of 6-gingerol, and their efficiency was comprehensively evaluated in terms of solvent type, temperature, and process duration. The obtained results demonstrated that extraction conditions have a significant impact on the gingerol yield. . Scientific mechanism of the process: Ethanol forms strong sigma-bonds with phenolic compounds. .

The result ultrasonic exstraction are presented (Table-3)

Table 3.

Result ultrasonic exstraction

In experiments conducted using the Soxhlet method at 58–60 °C, extending the process duration from 4 hours to 8 hours increased the mass fraction of gingerol. Using acetone as the solvent, 1.321% gingerol was isolated in 4 hours, while 8 hours yielded 2.84%. With 96% ethanol, 4 hours produced 3.2%, and 8 hours resulted in 3.43%. At the same time, theoretically, longer extraction times may increase the risk of thermal effects and oxidation; however, the obtained spectral data indicated that no structural degradation occurred.

Figure 1. Correlation between Extraction time and Gingerol yield

In ultrasonic-assisted extraction conducted at 37 kHz and 300 W, under conditions of 35–45 °C, gingerol was isolated in the range of 1.46–1.54% using ethanol as the solvent, and 1.12–1.24% using acetone (Table 2).

In the maceration method, the effects of solvent concentration and extraction duration were clearly observed. Using 96% ethanol for 12 hours, 1.064% gingerol was obtained, whereas with 70% ethanol for 24 hours, the content decreased to 0.14%. The increase in water content reduced gingerol solubility due to its relatively hydrophobic nature. Prolonged extraction also led to a decrease in the concentration gradient and possible oxidation processes, resulting in lower yields (Table 3).

FTIR spectroscopic analysis of the samples obtained after extraction and subsequent chromatographic purification showed the preservation of characteristic absorption bands for phenolic O–H (3400–3200 cm⁻¹), aliphatic C–H (2928–2850 cm⁻¹), ketone carbonyl C=O (approximately 1719 cm⁻¹), as well as aromatic ring and methoxy groups. No new intense foreign signals were observed in the spectra after purification, indicating that the structural integrity of the molecule was maintained during the extraction and purification processes. Based on the overall results, the highest efficiency for 6-gingerol isolation was achieved using Soxhlet extraction with 96% ethanol for 8 hours, yielding a maximum of 3.43%. Although ultrasonic-assisted extraction was optimal in terms of time and energy, it did not provide the maximum yield. The maceration method, while simple and inexpensive, showed lower efficiency in gingerol isolation. Thus, for obtaining high yields under laboratory conditions, the Soxhlet method was considered optimal. FTIR spectroscopy results confirmed that the obtained substance was 6-gingerol and that its structural stability was preserved.Comparing the FTIR spectra of 6-gingerol obtained by extraction and subsequently purified by chromatography, no new intense absorption bands corresponding to additional foreign functional groups were observed in the chromatographically purified sample. This indicates that the structural integrity of the compound was preserved and that no chemical changes occurred during the purification process.

Thus, the FTIR spectroscopy results confirm that the main structural fragments of the 6-gingerol molecule were preserved after the extraction and subsequent chromatographic purification stages.

The standard FTIR spectrum of 6-Gingerol (C₁₇H₂₆O₄) shows characteristic absorption bands corresponding to its functional groups, including: (Figure-2)

Figure 2. FTIR spectra of 6-Gingerol obtained by standart extraction and purified by chromatography

Figure 2. FTIR spectra of 6-Gingerol obtained by extraction and purified bychromatography

The broad peak around 3400 cm⁻¹ confirms the presence of phenolic –OH in gingerol. The strong peak at 1708.97 cm⁻¹ clearly indicates the ketone structure of gingerol. The range of 1600–1500 cm⁻¹ confirms the presence of an aromatic ring. Signals in the 1260–1030 cm⁻¹ range correspond to C–O bonds (phenol and alcohol). The FTIR spectrum of the isolated compound was compared with the standard 6-Gingerol spectrum reported in the literature. According to the spectral analysis, the compound contains functional groups characteristic of the 6-Gingerol molecule. The broad absorption band observed in the 3400–3200 cm⁻¹ range corresponds to the stretching vibrations of the phenolic O–H group. The intense absorptions at 2923.52 and 2853 cm⁻¹ indicate the stretching vibrations of aliphatic C–H bonds, confirming the presence of a long hydrocarbon chain in the molecule. The distinct absorption band observed at 1708,97 cm⁻¹ corresponds to the ketone carbonyl (C=O) group, indicating that the main structural element of the 6-Gingerol molecule is preserved. Absorptions in the 1500–1600 cm⁻¹ range correspond to the skeletal vibrations of the aromatic ring. The bands in the 1300–1000 cm⁻¹ region are attributed to the stretching vibrations of methoxy (–OCH₃) and alcohol C–O groups. (Figure-3).

No additional intense absorption bands unrelated to the 6-Gingerol structure were observed in the spectrum. A high degree of correspondence with the standard spectrum was noted in the main diagnostic regions.

On this basis, the isolated compound was confirmed to be 6-Gingerol according to the FTIR spectroscopy results.

SOXHLET METHOD YUSSC SPECTRA.The obtained chromatogram (DAD detector, λ = 282.4 nm) reflects the analysis performed for the precise identification and quantitative determination of 6-Gingerol. In the chromatogram, a major peak with high intensity is observed at a retention time of approximately 2.3–2.4 minutes. The sharp and symmetrical shape of this peak indicates that the compound is well separated and that optimal interaction with the column was achieved (Figure 4).

The signal recorded at a wavelength of 282.4 nm on the DAD detector corresponds to the aromatic structure of gingerol, as phenolic and aromatic systems exhibit maximum absorption in this range. This spectral correspondence additionally confirms the structural identification of the compound.

Overall, the chromatographic analysis results demonstrate the presence of 6-Gingerol in the isolated sample, its good separation, and a degree of purity sufficient for reliable identification.

Figure 4. Gingerol exstracted by Soxhlet-VGH result

CONCLUSION

The results of the study confirmed that the efficiency of 6-gingerol isolation from Zingiber officinale roots is directly dependent on the extraction method, solvent type, temperature, and process duration. Among the three extraction approaches—Soxhlet, ultrasonic-assisted extraction (UAE), and simple stirring (maceration)—the highest yield was observed with Soxhlet extraction using 96% ethanol for 8 hours, achieving a maximum gingerol content of 3.43 %. (Table-1),

In the maceration method, solvent concentration was identified as a decisive factor. Using 96% ethanol for 12 hours yielded 1.064% gingerol, whereas with 70% ethanol for 24 hours, the gingerol content decreased to 0.14%. This indicates the relatively hydrophobic nature of gingerol and that an increased water content reduces its solubility.

The isolated extracts were purified using column chromatography, and their structural identification was confirmed by FTIR and RP-HPLC methods. The FTIR spectra showed absorption bands characteristic of phenolic O–H (3400–3200 cm⁻¹), aliphatic C–H (2928–2850 cm⁻¹), ketone C=O (1719 cm⁻¹), aromatic ring (1500–1600 cm⁻¹), and C–O groups (1300–1000 cm⁻¹), exhibiting a high degree of correspondence with the standard 6-gingerol spectrum.

In RP-HPLC analysis, the sharp and symmetrical separation of the main peak on a C18 column at a wavelength of 282,4 nm confirmed the high purity of the compound. The stability of the retention time and the high peak intensity indicate that the quantitative determination of 6-gingerol was performed reliably. The results are consistent with previously published studies, further confirming the high selectivity and accuracy of the HPLC method for the determination of phenolic components.

This, based on the study results, Soxhlet extraction using 96% ethanol for 8 hours is recommended as the most effective method for isolating 6-gingerol under laboratory conditions. Although ultrasonic-assisted extraction is an energy-efficient and rapid alternative, it does not provide maximum yield. Maceration, while simple and economical, was assessed as a method with limited efficiency. The obtained results provide a scientific basis for selecting optimal pharmaceutical extraction conditions for gingerol and offer fundamental data for future mathematical optimization of the process and adaptation to industrial scale.

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