Norcolocynthenins A and B, two cucurbitane 3-nor-Triterpenoids from Citrullus colocynthis and their cytotoxicity

Naturally Occurring Norsteroids and Their Design and Pharmaceutical Application

The main focus of this review is to introduce readers to the fascinating class of lipid molecules known as norsteroids, exploring their distribution across various biotopes and their biological activities. The review provides an in-depth analysis of various modified steroids, including A, B, C, and D-norsteroids, each characterized by distinct structural alterations. These modifications, which range from the removal of specific methyl groups to changes in the steroid core, result in unique molecular architectures that significantly impact their biological activity and therapeutic potential. The discussion on A, B, C, and D-norsteroids sheds light on their unique configurations and how these structural modifications influence their pharmacological properties. The review also presents examples from natural sources that produce a diverse array of steroids with distinct structures, including the aforementioned A, B, C, and D-nor variants. These compounds are sourced from marine organisms like sponges, soft corals, and starfish, as well as terrestrial entities such as plants, fungi, and bacteria. The exploration of these steroids encompasses their biosynthesis, ecological significance, and potential medical applications, highlighting a crucial area of interest in pharmacology and natural product chemistry. The review emphasizes the importance of researching these steroids for drug development, particularly in addressing diseases where conventional medications are inadequate or for conditions lacking sufficient therapeutic options. Examples of norsteroid synthesis are provided to illustrate the practical applications of this research.

Citrullus colocynthis (L.) Schrad.: A Promising Pharmaceutical Resource for Multiple Diseases

Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) is widely distributed in the desert areas of the world. The fruit bodies of C. colocynthis are recognized for their wide range of nutraceutical potential, as well as medicinal and pharmaceutical uses. The plant has been reported for various uses, such as asthma, bronchitis, cancer, colic, common cold, cough, diabetes, dysentery, and jaundice. The fruit has been extensively studied for its biological activities, which include insecticide, antitumor, and antidiabetic effects. Numerous bioactive compounds have been reported in its fruit bodies, such as essential oils, fatty acids, glycosides, alkaloids, and flavonoids. Of these, flavonoids or caffeic acid derivatives are the constituents associated with the inhibition of fungal or bacterial growth, whereas eudesmane sesquiterpenes or sesquiterpene lactones are most active against insects, mites, and nematodes. In this review, the scientific evidence for the biological activity of C. colocynthis against insecticide, cytotoxic, and antidiabetic effects is summarized.

Cucurbitane-type triterpenoids from the fruits of Citrullus colocynthis

A phytochemical investigation of the fruits of Citrullus colocynthis resulted in the isolation of 21 structurally diverse cucurbitane triterpenoids, including 9 previously undescribed ones, colocynins A-I (1-9). Their absolute configurations were elucidated by means of quantum chemical electronic circular dichroism (ECD) calculations, CD exciton chirality method, and single-crystal X-ray crystallography. Colocynins A-C (1-3) represent the first examples of nonanorcucurbitane-type triterpenoids. An anti-acetylcholinesterase activity assay showed that 6, 10, 13, 18, and 20 exhibited inhibitory activities, with IC₅₀ values ranging from 5.0 to 21.7 μM. In addition, 18 and 21 showed significant cytotoxicity against PACA, A431, and HepG2 cells, with IC₅₀ values ranging from 0.042 to 0.60 and 3.6-14.4 μM, respectively.

The Antifungal and Antibacterial Effect of Citrullus Colocynthis: In Vitro Study

Introduction: Bacteria almost exclusively cause caries and other oral and dental diseases. This study evaluated the inhibitory effect of the alcoholic extract of Citrullus colocynthis on bacteria and fungi common in oral bacteria diseases. Method and materials: The ethanol extract and essential oil of Citrullus colocynthis were obtained via water distillation. After conducting phytochemical tests, including determination of total phenolic and flavonoid compounds of the extracts, GC-MASS test and microbial tests of the extracts were conducted on S. mutans, E. coli, S. salivarius, L. acidophilus, C. albicans, and S. aureus. The cytotoxicity test was assessed by MTT assay. Results: MIC and MBC values for S. mutans, S. salivalius, and L. acidophilus were 1.56 mg/ml and 3.12 mg/ml, respectively. Moreover, Citrullus colocynthis also has an inhibitory effect on bacteria and C. albicans at these concentrations, according to the DAD test. The survival rate of cells at concentrations of 5 mg/ml and 10 mg/ml was less than 50%, and at concentrations of 2.5 mg/ml and 1.25 mg/ml was less than 70% after 24 hours and 48 hours. Conclusion: According to the cytotoxicity results of this plant at concentrations of 1.56 mg/ml and 3.125 mg/ml, the ethanolic extract of C. colocynthis has inhibitory and lethal effects against pathogenic bacteria and fungi.