Phytochemical analysis, antioxidant, and anticholinesterase activities of ethanolic extracts from five ginger plants in Thailand

Five selected medicinal plants in the family Zingiberaceae, Alpinia nigra, Boesenbergia maxwellii, Etlingera araneosa, Meistera koenigii, and Wurfbainia biflora, were collected from Thailand. HPLC was used to determine the content of phenolic compounds in their ethanolic extracts. The total phenolic contents and the total flavonoid contents of M. koenigii were found to be higher than that of the others. The antioxidant activity of the extracts was assayed by two methods, namely ABTS and DPPH assays using HPTLC and a microplate spectrophotometer. Anticholinesterase activity was screened by the Ellman method against acetylcholinesterase, the chief enzyme of Alzheimer's disease. The results showed mild acetylcholinesterase effects. The results indicated that these five ginger species, especially M. koenigii have the potential to be a good source of natural antioxidants and anticholinesterase agents that could be further applied in the pharmaceutical industry.

Exploring Volatile Organic Compounds in Rhizomes and Leaves of Kaempferia parviflora Wall. Ex Baker Using HS-SPME and GC-TOF/MS Combined with Multivariate Analysis

Volatile organic compounds (VOCs) play an important role in the biological activities of the medicinal Zingiberaceae species. In commercial preparations of VOCs from Kaempferia parviflora rhizomes, its leaves are wasted as by-products. The foliage could be an alternative source to rhizome, but its VOCs composition has not been explored previously. In this study, the VOCs in the leaves and rhizomes of K. parviflora plants grown in a growth room and in the field were analyzed using the headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography and time-of-flight mass spectrometry (GC-TOF-MS). The results showed a total of 75 and 78 VOCs identified from the leaves and rhizomes, respectively, of plants grown in the growth room. In the field samples, 96 VOCs were detected from the leaves and 98 from the rhizomes. These numbers are higher compared to the previous reports, which can be attributed to the analytical techniques used. It was also observed that monoterpenes were dominant in leaves, whereas sesquiterpenes were more abundant in rhizomes. Principal component analysis (PCA) revealed significantly higher abundance and diversity of VOCs in plants grown in the field than in the growth room. A high level of similarity of identified VOCs between the two tissues was also observed, as they shared 68 and 94 VOCs in the growth room and field samples, respectively. The difference lies in the relative abundance of VOCs, as most of them are abundant in rhizomes. Overall, the current study showed that the leaves of K. parviflora, grown in any growth conditions, can be further utilized as an alternative source of VOCs for rhizomes.

A Review: Underutilized plant of Sabah and Its Potential Value

Underutilized plants are referred to a plant species which their potential is not fully utilized yet and they are usually found abundantly in certain local area but globally rare. Sabah is known for a high biodiversity and contains many underutilized plants. To our knowledge, this is the first review is to provide an overview information of medicinal value and pharmacological properties of underutilized plant in Sabah. Extract and metabolites in different part of several underutilized plant contains multiple beneficial bioactive compounds and exploitation of these compounds was supported by additional data which plays various biological activities including anti-atherosclerotic, anti-cancer, antihypercholesterolemic and anti-ulcerogenic. A handful of pharmacological studies on the natural product these underutilized plants have conclusively outlined the mode of action in treatment of several diseases and in other health aspects. This paper limits its scope to reviewe and highlight the potential of using underutilized plants in Sabah only which could serve as reliable resource for health product development in pharmaceutical and nutraceutical through continuous discovering of more active and sustainable resources as well as ingredients for food and medicine.

Comparison and HPLC quantification of antioxidant profiling of ginger rhizome, leaves and flower extracts

Background

In the present era, the attention of nutritionist diverted towards the bioactive entities present in natural sources owing to the presence of health boosting perspectives against lifestyle related disarrays.

Methods

In this context, different parts of ginger crop i.e. rhizome, leaves and flower of variety Suravi (ID no. 008) were used for the preparation of ginger extracts with 50% methanol, 50% ethanol and water via rotatory shaker for 45 min. After that, different phytochemical analysis and in vitro analyses were carried out to determine the antioxidant potential of these extracts. Lastly, the best selected extracts from each part was quantified through HPLC.

Results

The results of current investigated indicated that ethanol extract proved to have maximum quantity of phytoceutics as compared to methanol and water. The maximum TPC, flavonoids, flavonols, DPPH assay, antioxidant activity, FRAP assay, ABTS assay and metal chelating potential was observed in ginger leaves as 780.56 ± 32.78 GAE/100 g, 253.56 ± 10.65 mg/100 g, 49.54 ± 1.74 mg/100 g, 75.54 ± 3.17%, 77.88 ± 3.27%, 105.72 ± 4.44 μmole TE/g, 118.43 ± 4.97 μmole TE/g and 35.16 ± 1.48%, respectively followed by ginger flowers and ginger rhizome. The lowest antioxidant activity was estimated in ginger rhizome. On the basis of phytochemical profiling and in vitro analyses, ethanol extracts of ginger flowers, leaves and rhizome were selected for the quantification through HPLC.

Conclusion

The findings proved that maximum 6-gingerol was present in ginger leaves (4.9 mg/g) tackled by ginger flowers (2.87 mg/g) and ginger rhizome (1.03 mg/g).

Nutritional Compositions and Phytochemical Properties of the Edible Flowers from Selected Zingiberaceae Found in Thailand

The nutritional compositions and phytochemical properties of eight edible flowers of the ginger family (Zingiberaceae) commonly found in Thailand are reported herein. The plant genera investigated were Zingiber (Ginger, Phlai Dam, Krathue), Hedychium (two morphological filament forms), Curcuma (Ao), Etlingera (Torch ginger), Amomum (Chi Kuk), and Alpinia (Galangal), which are eaten fresh or cooked as ingredients in the preparation of many Thai dishes. The proximate compositions (moisture, ash, fiber, protein, fat, and carbohydrate contents) varied among the different genera. The plants sampled were generally low in fat content (<1%), which contributed as little as 30% of the total caloric energy. Edible plant parts contained substantially high amounts of potassium (max. 737.21 mg/100 g), calcium (max. 140.15 mg/100 g), and iron (~0.32 mg/100 g). Among the tested samples, torch ginger had the highest vitamin C content (1.05 mg/100 g), total phenolic and total flavonoid contents, as well as 2,2-diphenyl-1-picrylhydrazyl activity. On the other hand, the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assay suggested that Hedychium species possessed the highest antioxidant activity (~5.38 mg TEAC/g extract). Our results prove that edible plants of the Zingiberaceae family found in Thailand are rich sources of potentially important nutrients.