Influence of Thermal Treatment on the Composition of Alpinia officinarum Rhizome.

Alpinia officinarum is a representative of the Zingiberaceae family, which is known for its wide use in the food and pharmaceutical industries also due to its precious pharmacological potential. The major aim of the present study was to evaluate the influence of thermal treatment on the composition of the rhizome of Alpinia officinarum and its antioxidant activity. The fresh rhizome was subjected to various thermal treatment processes-boiling, frying and microwave heating during various time intervals-and their composition and antioxidant activity were determined using chromatographic (HPLC - High Performance Liquid Chromatography and HPLC-MS - High Performance Liquid Chromatography Mass Spectrometry) and spectrophotometric (DPPH and TPC - Total Phenolic Content) methods. Pinobanksin was the main compound found in the extract of the fresh rhizome (537.79 mg/kg), followed by galangin (197.7 mg/kg) and zingerone (185.5 mg/kg). The effect of thermal treatment on the rhizome composition was varied. In general, thermal processing significantly decreased the content of active compounds in the rhizome. However, there were some exceptions-boiling for 4 min significantly increased the content of pinobanksin (1162.4 mg/kg) and galangin (280.7 mg/kg), and microwave processing for 4 min increased the content of pinocembrin (213 mg/kg). It was found that boiling and microwave treatment significantly increased the antioxidant activity of the processed rhizomes.

Influence of Diet on the Bioavailability of Active Components from Zingiber officinale Using an In Vitro Digestion Model.

Ginger (Zingiber officinale Rosc.) is a plant known all over the world that is used as a spice and as an ingredient in drinks, dietary supplements, and cosmetics. The growing availability of its fresh rhizomes makes it even more likely to be used in the diet, mainly due to its beneficial health properties and high content of polyphenols (gingerols and shogaols). The main goal and motivation of the authors was to assess the bioavailability of active substances contained in the extract from ginger rhizomes in the presence of various types of diets using the in vitro digestion method, enabling simulation of the processes occurring during the digestion and absorption of metabolites in the small intestine. For the qualitative and quantitative analyses, the HPLC-MS (High Performance Liquid Chromatography-Mass Spectrometry) and HPLC (High Performance Liquid Chromatography) techniques were used, respectively. Based on the obtained results, it was found that the best bioavailability of the selected ginger polyphenols (6-gingerol, 8-gingerdione, 8-shogaol, and 10-gingerdione) was estimated for a high-fiber diet, while the weakest results were obtained for standard and basic diets. In the case of the high-fiber diet, the bioavailability of the mentioned compounds was estimated as 33.3, 21.4, 6.73, and 21.0%, while for the basic diet, it was only 21.3, 5.3, 2.0, and 1.0%, respectively.

Impact of Thermal Processing on the Composition of Curcuma longa Rhizome.

Curcuma longa L. (Zingiberaceae), known as turmeric, is a perennial tuberous plant from the genus Curcuma, which includes about 100 plant species. The chemical composition of the turmeric rhizome is very diverse. Diarylheptanoid derivatives, also known as curcuminoids (of which curcumin, demethoxycurcumin and bisdemethoxycurcumin are the most important representatives), are the major active constituents of the plant rhizome. Many extracts used in the food and pharmaceutical industries are produced from thermally processed rhizome, when there are significant changes in the composition of the main compounds. Therefore, the aim of the study was to compare how the type of thermal treatment affects the content of curcuminoids and the antioxidant properties of the rhizome. The plant material was subjected to three different methods of thermal processing-microwave heating, boiling and frying in different time intervals. The chemical composition and antioxidant activity of the processed rhizome was evaluated using LC-MS (liquid chromatography-mass spectrometry), HPLC (high-performance liquid chromatography) and spectrophotometric methods (a DPPH test and TPC assay). Obtained results revealed that curcumin was the major curcuminoid present in all samples (113.92 mg/g of the fresh rhizome). Significant correlation between the type and time of the thermal processing and the composition of turmeric samples was revealed. A traditional boiling process lasting for 10 min was the most beneficial process in terms of the curcuminoid content (204 mg/g of curcumin) and antioxidant activity of the samples.

Impact of Thermal Processing on the Selected Biological Activities of Ginger Rhizome-A Review.

Ginger (Zingiber officinale Rosc.) is a spice, medicinal and cosmetic plant that has been known for centuries. It can be used in dried, fresh, marinated or candied form, and is also an essential ingredient in well-known curry blends. Ginger rhizomes are often freeze-dried as the first step in the preparation of the raw material. Many studies have proved that the composition and biological activity of ginger changes due to thermal processing. Therefore, the aim of the review was to summarize the scientific results on the impact of traditional and unconventional methods of the heat treatment of ginger rhizomes and their influence on the antioxidant and other selected biological activities of the plant. The review of the available scientific data is inconclusive, and it is hard to state unequivocally whether the thermal treatment of the raw material increases or decreases biological activity. Based on the presented literature review, it can be concluded that traditional cooking and microwave processing in general decrease the antioxidant activity of the ginger rhizome, whereas frying, autoclaving, blanching or traditional drying in the sun mostly lead to a significant increase in ginger activity. Interesting data were presented in the works describing the freeze-drying process during which the antioxidant potential of ginger increased.

Impact of Thermal Processing on the Composition of Secondary Metabolites of Ginger Rhizome-A Review.

Ginger (Zingiber officinale Rosc.) is both a commonly used spice, and an ingredient of various dietary supplements and medications. Its diverse applications result from the range of health benefits that this plant brings thanks to the presence of active compounds (secondary metabolites) in the matrix. Even if several studies underline a stronger pharmacological activity of fresh ginger rhizomes, the unprocessed plant is relatively rarely used. Ginger rhizomes are subjected to thermal processing, such as boiling, blanching, steam drying and others, at different temperature and time settings. Additionally, freeze-drying of the rhizomes is used as the first step in the preparation of raw material. It was proved that the composition of secondary metabolites of the Zingiber officinale rhizome changes upon the influence of temperature. Therefore, the aim of the review was to put together scientific results on the impact of traditional and unconventional methods of heat treatment on ginger rhizomes and to show the compositional differences that they induce in the plant matrix. Variations in the content and the transformation of some compounds into other metabolites will be also discussed, with particular attention paid to two major groups of secondary metabolites present in the plant, namely, phenolics and terpenes.

The Phenolic Compounds Profile and Cosmeceutical Significance of Two Kazakh Species of Onions: Alliumgalanthum and A. turkestanicum.

Numerous species of Allium genus have been used in the traditional medicine based on their vast biological effects, e.g., antimicrobial, digestion stimulant, anti-sclerotic, soothing, antiradical or wound healing properties. In this work, unpolar and polar extracts from two lesser-investigated species of Allium growing in Kazakhstan, Alliumgalanthum Kar. & Kir. (AG) and A. turkestanicum Regel. (AT), were studied for their composition and biological effects. In the HPLC-ESI-QTOF-MS/MS analyses of water and alcoholic extracts simple organic acids, flavonoids and their glycosides were found to be the best represented group of secondary metabolites. On the other hand, in the GC-MS analysis diethyl ether, extracts were found to be rich sources of straight-chain hydrocarbons and their alcohols, fatty acids and sterols. The antimicrobial activity assessment showed a lower activity of polar extracts, however, the diethyl ether extract from AT bulbs and AG chives showed the strongest activity against Bacillus subtilis ATCC 6633, B. cereus ATCC 10876, some species of Staphylococcus (S. aureus ATCC 25923 and S. epidermidis ATCC 12228) and all tested Candida species (Candida albicans ATCC 2091, Candida albicans ATCC 10231, Candida glabrata ATCC 90030, Candida krusei ATCC 14243 and Candida parapsilosis ATCC 22019) with a minimum inhibitory concentration of 0.125-0.5 mg/mL. The highest antiradical capacity exhibited diethyl ether extracts from AG bulbs (IC50 = 19274.78 ± 92.11 mg Trolox eq/g of dried extract) in DPPH assay. In ABTS scavenging assay, the highest value of mg Trolox equivalents, 50.85 ± 2.90 was calculated for diethyl ether extract from AT bulbs. The same extract showed the highest inhibition of mushroom tyrosinase (82.65 ± 1.28% of enzyme activity), whereas AG bulb ether extract was the most efficient murine tyrosinase inhibitor (54% of the enzyme activity). The performed tests confirm possible cosmeceutical applications of these plants.

Applications of Tea (Camellia sinensis) and its Active Constituents in Cosmetics.

Studies on the cosmetic applications of plant extracts are increasingly appearing in the scientific literature, which is due to the growing popularity of skincare products around the world. In the light of the observed changes, a return to natural treatment and skincare with cosmetics free of harmful substances or toxic preservatives is visible. Currently, tea extracts, due to their rich composition and various biological actions, play an important role among the dietary supplements and cosmetics. This review is intended to collect the reports on the properties of the tea plant, its extracts and preparations in cosmetology: for skin care products and for the treatment of selected dermatological diseases. Particular attention is paid to its antioxidant, anti-hyaluronidase, anti-inflammatory, slimming, hair-strengthening, photoprotective and sealing blood vessels properties.