Comparison of Organosulfur and Amino Acid Composition between Triploid Onion Allium cornutum Clementi ex Visiani, 1842, and Common Onion Allium cepa L., and Evidences for Antiproliferative Activity of Their Extracts

Abstract

Species that belong to the genus Allium have been widely used for human food and traditional medicine. Their beneficial health effects, as well as the specific aroma, are associated with their bioactive chemical compounds, such as sulfur compounds and flavonoids. Gas chromatography and mass spectrometry (GC-MS) and reverse-phase high-performance liquid chromatography (reverse-phase HPLC) were used to identify organosulfur and amino acid content of triploid hybrid onion, Allium cornutum Clement ex Visiani, 1842, and common onion, Allium cepa L. Allium extracts were tested for their antiproliferative activity in three human cancer cell lines (HeLa, HCT116, and U2OS). DNA fragmentation and DAPI staining analysis were performed on HeLa cells to evaluate the effect of extracts on DNA damage and cell morphology. The mRNA expression of p53, Bax, and Caspase-3 genes involved in apoptosis were analyzed by real-time PCR. Using GC-MS, 27 compounds were found in two Allium species headspaces. Differences were noted among the main compound abundance in the headspace (although the major thiols and disulfides were qualitatively identic in both Allium species) and dipropyl disulfide, diisopropyl trisulfide, and (Z)-prop-1-enyl propyl trisulfide were predominant sulfides. Identification of amino acids and their quantities were determined by reverse-phase HPLC. Most abundant amino acids in both onions were arginine (Arg) and glutamic acid (Glu). The results of cytotoxicity testing confirmed antiproliferative effects of both species. The DNA fragmentation assay, DAPI staining and real time PCR analysis confirmed that A. cornutum and A. cepa extracts induced apoptosis in HeLa cells. This study presents the evidence for possible therapeutic use of A. cornutum and A. cepa extracts against human cervical carcinoma cell line.

Variation in Amino Acids Composition through Pre column Derivatisation using Phenylisothiocyanate by HPLC in Some Economically Important Less Explored Wild Allium Species of Western Himalayas

“…Schuphan & Schwerdtfeger 19 reported that arginine and glutamic acid found in abundant quantity, than other amino acids in Allium cepa. Fredotovic 14 , et al, reported amino acid composition of two Allium species viz. A. cornutum and A. cepa extracts and observed that the most abundant amino acids in both onions were glutamic acid and arginine 14 .…”

Investigation of the anti-hyperglycemic and antioxidant effects of wheat bread supplemented with onion peel extract and onion powder in diabetic rats

“…3) but, the effect was more pronounced in the 3% OPE group as compared with other groups suggesting that onion peel extract can be beneficial against oxidative stress. Previous studies indicated the potent antioxidant potential of onion towards increasing the GSH level and upholding the antioxidant enzymatic activities within the normal range [84,85].…”

Transcriptome and phytochemical analyses provide insights into the organic sulfur pathway in Allium hirtifolium

“…For gas chromatography–mass spectrophotometry (GC/MS) investigation, bulb, stem, and flower tissues were dried at room temperature (25 °C). At this point, isolation of the volatile compounds was carried out for 1 g of each sample by utilizing a manual Solid Phase Microextraction (SPME) fiber with the layer of carboxen/polydimethylsiloxane (CAR/PDMS) 47 . GC examination was done on the Thermoquest-Finnigan gas chromatograph instrument (Thermo Fisher Scientific).…”