Berberis Species of Pakistan: A Rich Source of Phytochemicals with Reducing Potential for Green Synthesis of Metallic Nanoparticles and as an Alternate Host to Fungal Pathogens

Abstract

Berberidaceae family, is considered as one of the most beneficial in traditional medicine. In early 1900, this family was reported to be alternate host to various cereal pathogens. Thus, making the plants of this family both friend and foe. This dissertation illustrates both beneficial and damaging potentials of Berberis species of Pakistan. Exploring the traditional medical plants for bioactive compounds, has been pivotal part of modern medicine. Various bioactive compounds have been identified, characterized and utilized from Berberis species in recent past. Almost all of these studies focused on the bioactive compounds of the roots of Berberis species. Therefore, in the present study phytochemicals, nutritional and biological profile is carried out using various organs of the Berberis plant. In the present study, we aimed to analyse three parts (root, stem and leaf extracts) of eight selected Berberis species as alternate and suitable means for phytochemicals, nutritional, and antioxidant purposes through the conservational approach. There are limited scientific studies that confirm the detailed biological potential of Berberis species. Moreover, in present study we examined all parts of dominant Berberis species of Pakistan. The study illustrates the presence of significant concentrations of mineral elements, phytochemicals, and antioxidant potential. Thus, can be utilized as a natural antioxidant, antimicrobial and nutritional complements in herbal and food industries. Spectroscopic profile revealed that all Berberis species comprise a rich source of elements in decreasing order B. balochistanica > B. royleana > B. parkeriana > B. pseudoumbellata > B. pachyacantha > B. calliobotrys > B. lyceum > B. orthobotrys. The HPLC results revealed that berberine was abundantly present in the root extracts of all selected species. Similarly, spectroscopic profile exhibited highest total phenolic (TPC) and total flavonoids contents (TFC) in B. pseudoumbellata, B. royleana, B. pachyacantha and B. balochistanica. In addition, all selected species showed antioxidant activity, but leaf showed best antioxidant potential as compared to roots and shoot. This is first report of essential nutrients and phytochemical compounds with high antioxidants activity indicating comparison between roots and shoots. These findings will be useful in the conservation of medicinal plants by discouraging the uprooting of underground parts for medicinal purposes. To demonstrate the biological application of Berberis species, B. balochistanica plant with an astonishing amount of minerals and antioxidant activities was selected as model organism in present dissertation. B. balochistanica, is extensively used by local people as traditional medicine. Extensive utilization of the roots of this plant by local community has led xvii to depletion of this plant in Baluchistan province of Pakistan. Little is known about the phytochemical and biological significance of its alternative parts of these distinct species. Thus, this study was conducted using a rational approach by substituting the underground parts with renewable aerial parts to decrypt phytonutritional profile along with antioxidant, antibacterial, antifungal, antihaemolytic, DNA damaging, cytotoxic and phytotoxic potentials for comparison with roots. It was observed that all three plant parts; roots, stem, and leaves of B. balochistanica showed substantial antihaemolytic, DNA protecting and cytotoxic activities. Additionally, all parts particularly leaf extract retarded the bacterial growth of Staphylococcus aureus, Klebsiella pneumonia and Escherichia coli. Similarly, extracts of all parts reduced the mycelial growth of all tested fungal pathogens. Hence, these results signify a remarkable biological potential of B. balochistanica, especially its aerial parts. This study will recommend preserving of this endemic plant by discouraging the usage of its roots. The utilization of plant natural material in bio fabrication of nanoparticles is recognized as a green technology. The present study revealed the importance of aerial parts of Berberis plants in the green synthesis of nanoparticles. The presence of valuable phytochemicals in stem and leaf extracts of B. balochistanica helped in stabilizing, capping, and reducing nickel salt into BB-NiONPs. The synthesis of nanoparticles was confirmed by various microscopic and spectroscopic techniques like UV visible, FTIR, XRD, EDX and SEM. Both stem and leaf extracts of B balochistanica successfully reduce and capped the NiONPs with fine size (31.44 nm and 21.00 nm) and crystalline rhombohedral shape. Both nanoparticles (BBS-NiONPs and BBL-NiONPs) were exposed to multiple in vitro and in vivo bioactivities to ascertain their beneficial biological applications. They exhibited strong antioxidant activities in terms of total antioxidant capacity (64.77 and 59.59 %) and 2, 2-diphenyl-1-picrylhydrazyl (71.48 and 69.98 %); and cytotoxic potential with IC50 (10.40 and 49.10 µg/mL). The synthesized nanoparticles restricted the bacterial and fungal pathogenic growth at 1000, 500 and 100 µg/mL. Additionally, these nanoparticles showed stimulatory efficacy by enhancing seed germination rate and seedling growth at 31.25 and 62.5 µg/mL. In aggregate, both extracts have a remarkable number of bioactive compounds which makes the green biosynthesis of NiONPs easy, economical, and safe. The biochemical potential of BBS-NiONPs BBL-NiONPs can be useful in various biomedical and agricultural fields, and could be used as nanomedicine and nano fertilizer. On the other hand, the Barberry eradication program, initiated by federal and state cooperative plant disease control campaign in United States started in 1918. The aim of the xviii program was to eradicate common barberry (B. vulgaris) in efforts to reduce Puccinia graminis f. sp. tritici impact on wheat production. Barberry is an alternate host to various fungal pathogens of important cereal crops. Importantly, all these pathogens complete their sexual life cycles on Barberry plants. Thus, this plant plays a pivotal role to help in the emergence of new races after genetic recombination during the aecial stage. Different Berberis species also serve as a seasonal bridge for stem and stripe rust pathogen in Pakistan and neighbouring countries. In this study the diversity of rust on Berberis spp. was investigated at molecular and morphological levels. Simple Sequence Repeat (SSR) markers were used to investigate the presence of different rust on Barberry collected from four mountainous regions of Pakistan. Based on aecial growth and spore morphology, rust was divided into two groups i.e., localized (Puccina graminis) and systematic (Puccina arrhenatheri). In total, 25 of 46 SSR markers were found to be useful for the screening of selected rusts collected from barberry. SSR analysis revealed three Berberis species namely B. balochistanica, B. pachyacantha and B. lycium as alternate hosts of wheat stem rust (WSR), while B. lycium was also identified as an alternate host of oat stem rust (OSR). However, no barberry was recognized as an alternate host of wheat yellow rust (WYR) in natural conditions. Overall, this study has confirmed that barberry serves as an alternate host for only stem rust in Pakistan. Keywords: medicinal plants; Berberis species; Phytochemicals, Nutritional and biological potentials, Plant parts substitution; Green synthesis; NiONPs; Biological and Nano fertilizer applications; Wheat stem rust, Wheat strip rust, SSR markers, Aecium