Biotechnology of camptothecin production in Nothapodytes nimmoniana, Ophiorrhiza sp. and Camptotheca acuminata.

Cancer is probably the deadliest human disease in recent years. In the past few years, rapid clinical progress has been made in the field of anticancer drug development. Plant secondary metabolites have been noted as extremely efficacious as promising natural source for anticancer therapy for many years. Camptothecin (CPT) is one of the popularly used anti-tumor drugs possessing clinically proven properties against a plethora of human malignancies that include ovarian and colorectal cancers. For the first time, CPT was obtained from the extracts of a Chinese medicinal tree, Camptotheca acuminata Decne. from the family Cornaceae. Subsequently, CPT was also isolated from the bark of Nothapodytes foetida (Wight) Sleumer (Icacinaceae). However, the availability of enough natural sources for obtaining CPT is a major constraint. Due to overexploitation and harvesting, loss of habitat, excessive trading, and unfavorable environmental factors, the natural source of CPT has become extinct or extremely limited and hence they are red listed under endangered species. Conventional propagation has also failed to meet the ever-expanding demand for CPT production. With this, biotechnological toolkits have constantly been used as a boon to produce sustainable source, utilization, and ex situ conservation of medicinal plants. The approaches serve as a supplement to traditional agriculture in the mass production of plant metabolites with potent bioactivities. Non-availability of enough anticancer medicine and the requirement to satisfy current demands need a sustainable source of CPT. With this background, we present a comprehensive review on CPT discovery, its occurrence in the plant kingdom, biosynthesis, phytochemistry, pharmacological properties, clinical studies, patterns of CPT accumulation, and biotechnological aspects of CPT production in three plants, viz., N. nimmoniana, Ophiorrhiza species, and C. acuminata.Key points• Biotechnological approaches on production of camptothecin from Nothapodytes nimmoniana, Ophiorrhiza species, and Camptotheca acuminata• In vitro propagation of camptothecin-producing plants• Genetic diversity and transgenic research on camptothecin-producing plants.

Anticancer Properties of Different Solvent Extracts of Cucumis melo L. Seeds and Whole Fruit and Their Metabolite Profiling Using HPLC and GC-MS.

Honeydew melon (Cucumis melo L.) is an oval-shaped delicious fruit of one cultivar group of the muskmelon with immense nutritional importance and is extensively consumed by many tropical countries. The effect of various organic solvents on the recovery of phytochemicals from honeydew melon plant fruits and seeds was assessed. Further, High-Performance Liquid Chromatography (HPLC) was used to examine and assess the contents of phenolic acid (gallic acid) and flavonoid (rutin) compounds. The use of gas chromatography-mass spectrometry (GC-MS) analysis explained the presence of volatile phytocompounds in the extracts. The use of organic solvents had a substantial impact on the total dry weight and extract yield. In general, the solvent-extracted constituents remained in the order of methanol>chloroform>distilled water for both honeydew melon seeds and whole fruit. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) was used to assess the cytotoxicity effect against PC3, HCT116, HeLa, and Jurkat cell lines. The chloroform extract exhibited a good cytotoxic activity against all cell lines as compared to other solvent extracts. HPLC analysis revealed the occurrence of gallic acid content of 0.102 ± 0.23 mg/10 mg of dry whole fruit extract, while 10 mg of dry seed extract contained only 0.022 ± 0.12 mg of gallic acid content. Likewise, rutin content was observed to be 0.224 ± 0.31 mg and 0.1916 ± 0.82 mg/10 mg of dry whole fruit and seed extract, respectively. Further, GC-MS analysis revealed the presence of a total of 37 compounds in chloroform extract of whole fruit, while only 14 compounds were found in seed extract. Nevertheless, more examinations are needed to identify and characterize other metabolites from honeydew melon and evaluate their pharmacological importance.

Anticancer and Antibacterial Activities of Silver Nanoparticles (AgNPs) Synthesized from Cucumis melo L.

The current investigation reports the structural and biological evaluation of silver nanoparticles (AgNPs) biosynthesized from the pericarp extract of Cucumis melo L. (muskmelon). The AgNPs were characterized by ultraviolet-visible (UV-Vis) spectrophotometry, XRD (X-ray diffraction), SEM (scanning electron microscopy) and EDAX (energy-dispersive X-ray spectroscopy). The XRD analysis showed that biosynthesized AgNPs were having FCC (face centered cubic) crystalline structures. Further, the SEM and EDAX showed spherically shaped AgNPs having an average size of 25 nm. The AgNPs effectively inhibited the growth of Bacillus subtilis and Escherichia coli. Moreover, the cytotoxic assay of AgNPs revealed effective cytotoxicity against different cancer cells, such as HeLa, HCT-116, PC-3 and Jurkat in a dose reliant way. The cell viability was noticed to range from 50% to 60% with IC50 values ranging from 150 µg/mL to 224 µg/mL. The lower cell viability indicates the toxic effects of biosynthesized AgNPs against these malignant cells. Thus, the current study shows that these biosynthesized AgNPs could be utilized in various medical applications in near future.