Bioactivities and green advanced extraction technologies of ginger oleoresin extracts: A review

An overview of 6-shogaol: new insights into its pharmacological properties and potential therapeutic activities

Ginger (Zingiber officinale Roscoe) has traditionally been used as a cooking spice and herbal medicine for treating nausea and vomiting. More recently, ginger was found to effectively reduce the risk of diseases such as gastroenteritis, migraine, gonarthritis, etc., due to its various bioactive compounds. 6-Shogaol, the pungent phenolic substance in ginger, is the most pharmacologically active among such compounds. The aim of the present study was to review the pharmacological characteristic of 6-shogaol, including the properties of anti-inflammatory, antioxidant and antitumour, and its corresponding molecular mechanism. With its multiple mechanisms, 6-shogaol is considered a beneficial natural compound, and therefore, this review will shed some light on the therapeutic role of 6-shogaol and provide a theoretical basis for the development and clinical application of 6-shogaol.

Structural Characteristic, Strong Antioxidant, and Anti-Gastric Cancer Investigations on an Oleoresin from Ginger (Zingiber officinale var. roscoe)

It is known that ginger oleoresin contains various active components and possesses bioactivities. In this study, ginger oleoresin from Chinese ginger (Zingiber officinale var. roscoe) was extracted using a CO2 supercritical fluid extraction method with a 0.52% yield (g/g), based on dry weights. Zingiberene with a content of 51.6 mg/g was the main volatile in the ginger oleoresin. In total, 17 phenolic compounds were identified, and their contents were calculated as 587.54 mg/g. Among them, a new gingertriol was detected in the Z. officinale. Antioxidant activity tests showed that the ginger oleoresin and six gingerols exhibited strong scavenging free radical activities, and the zingerone exhibited the strongest antioxidant activity, with IC50 values of 11.3 µg/mL for the 2, 2'-diphenyl-1-picrylhydrazyl radical and 19.0 µg/mL for the 2, 2'-amino-di (2-ethyl-benzothiazoline sulphonic acid-6) ammonium salt radical cation, comparable to vitamin C. Ginger oleoresin inhibits HGC-27 human gastric cancer cell proliferation at a rate of 4.05~41.69% and induces cell apoptosis at a rate of 10.4~20.9%. The Western blot result demonstrated that the AKT signaling pathway has the potential mechanism of ginger oleoresin acting on HGC-27 cells. The anticancer potential of the gingerol standards on HGC-27 cells followed the order of 8-gingerol > 6-gingerol > 10-gingerol > zingerone. The different antioxidant and anticancer potentials of the ginger phenolic compounds could be attributed to the presence of hydroxyl groups in the unbranched 1-alkyl chain and the length of carbon side chain. Consequently, ginger oleoresin shows substantial antioxidant and anticancer therapeutic potential and can be used for novel food-drug development.

Effect of microwave-assisted drying and extraction of 6-Shogaol from Zingiber officinale Roscoe

Ginger (Zingiber officinale Roscoe, Zingeberaceae) is a medicinal plant widely used as food, spice, or flavoring agent worldwide. 6-Shogaol is a compound of prime interest in exhibiting anti-inflammatory, antioxidant and chemopreventive effects. The objective of the study is to investigate the effect of microwave-assisted drying (MAD) followed by microwave-assisted extraction (MAE) so as to produce 6-Shogaol enriched Ginger with improved therapeutic benefits. Various drying techniques viz. shade drying, tray drying, microwave-assisted drying and osmotic dehydration as a pretreatment were used for drying Ginger rhizomes. The dried rhizomes were extracted by conventional solvent extraction and microwave-assisted extraction techniques and tested for content of 6-Shogaol using the newly developed HPLC method whereas total flavonoid and polyphenol content were determined using the UV spectrophotometric method. Subjecting the microwave dried Ginger to microwave-assisted extraction for 45 min at constant power level of 284 W resulted in a significant rise in the extractability of 6-Shogaol (1.660 ± 0.018), total polyphenols (855.46 ± 5.33) and flavonoids (617.97 ± 6.40) compared to the conventional method of extraction. The proposed Ginger processing method of microwave drying followed by microwave extraction outperforms traditional methods in terms of speed, convenience, and performance thus can be scaled up to industrial levels.

Ginger Bioactives: A Comprehensive Review of Health Benefits and Potential Food Applications

Ginger is an herbaceous and flowering plant renowned for its rhizome, which is widely employed as both a spice and an herb. Since ancient times, ginger has been consumed in folk medicine and traditional cuisines for its favorable health effects. Different in vitro and in vivo studies have disclosed the advantageous physiological aspects of ginger, primarily due to its antioxidant, anti-inflammatory, antimicrobial, and anti-carcinogenic properties. These health-promoting features are linked to the variety of bioactive compounds that are present in ginger. Following the advancement in consumer awareness and the industrial demand for organic antioxidants and functional ingredients, the application of ginger and its derivatives has been broadly investigated in a wide range of food products. The prominent features transmitted by ginger into different food areas are antioxidant and nutraceutical values (bakery); flavor, acceptability, and techno-functional characteristics (dairy); hedonic and antimicrobial properties (beverages); oxidative stability, tenderization, and sensorial attributes (meat); and shelf life and sensorial properties (film, coating, and packaging). This review is focused on providing a comprehensive overview of the tendencies in the application of ginger and its derivatives in the food industry and concurrently briefly discusses the beneficial aspects and processing of ginger.

Orange Pomace and Peel Extraction Processes towards Sustainable Utilization: A Short Review

More than 58 million metric tonnes of oranges were produced in 2021, and the peels, which account for around one-fifth of the fruit weight, are often discarded as waste in the orange juice industry. Orange pomace and peels as wastes are used as a sustainable raw material to make valuable products for nutraceuticals. The orange peels and pomace contain pectin, phenolics, and limonene, which have been linked to various health benefits. Various green extraction methods, including supercritical carbon dioxide (ScCO₂) extraction, subcritical water extraction (SWE), ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE), are applied to valorize the orange peels and pomace. Therefore, this short review will give insight into the valorization of orange peels/pomace extraction using different extraction methods for health and wellness. This review extracts information from articles written in English and published from 2004 to 2022. The review also discusses orange production, bioactive compounds in orange peels/pomaces, green extractions, and potential uses in the food industry. Based on this review, the valorization of orange peels and pomaces can be carried out using green extraction methods with high quantities and qualities of extracts. Therefore, the extract can be used for health and wellness products.