Current Botany

Phytochemical analysis and antibacterial activity of Andrographis lineata Nees (Acanthaceae)

B. K. Rathna Kumari, H. R. Raveesha — Thu, 18 Jan 2024 00:00:00 +0530

Andrographis lineata Nees is an erect herb and has been used as a traditional medicine against many diseases. The present study was to investigate the phytochemical analysis and antibacterial activity of A. lineata plant extracts. The methanolic extracts of A. lineata showed a variety of phytochemicals such as alkaloids, flavonoids, phenols, tannins, terpenoids etc. The quantitative estimation of major phytochemical constituents revealed maximum amount of phenolic content in the roots and alkaloids in both the stem and leaf. Correspondingly, the highest amount of tannins and terpenoids were recorded in the leaf and flavonoids in the root samples. Furthermore, the plant extracts of A. lineata showed antibacterial activity against both Gram-positive and Gram-negative bacterial strains. Comparatively, stem extract was effective against Streptococcus mutans (18.19±0.04 mm), leaf extract against Enterobacter faecalis (24.13±0.14 mm) and root extract against Bacillus subtilis (24.09±0.14 mm) at 30 μg/μL concentration. However, the leaf extract was more effective against Escherichia coli (25.13±0.16 mm), Pseudomonas aeruginosa (20.20±0.13 mm) and Klebsiella pneumoniae (18.18±0.17 mm) at 30 μg/μL concentration. The studies infer that the phytochemical constituents of A. lineata have antibacterial properties and these herbs may be considered as the medicinal plant for treating bacterial diseases.

Engineered nanomaterials in plant protection: their controlled, site-directed delivery and phytotoxicity

Thu, 22 Feb 2024 00:00:00 +0530

Engineered nanomaterials (ENMs) are being produced and utilized in certain nanoformulations almost in every sector of development including agriculture. The diverse groups of engineered nanoparticles (ENPs) provide numerous benefits in agriculture, but their bulk and direct delivery pose a serious risk to the plants and ecosystem for a long time. The harmful effects on all the exposed living systems are owing to the variable shape, size, behaviour and toxic properties of ENPs. The accumulated ENMs in plant tissue may lead to biomagnification at a higher trophic level causing severe toxicity. The hazardous effects of these entities can be minimized with their controlled, specified and targeted delivery to the crop plants. Such smart-delivery systems as Ehrlich’s ‘magic bullets’ are being demonstrated for nutrients and growth enhancers, fertilizers, pesticides and weedicides; as well as biomolecules in plant genetic engineering. This review summarizes the benefits of ENMs and ENPs in plant protection to increase crop productivity, their targeted delivery suggesting sustainable utilization, and the available information on phytotoxicity.

In vitro regeneration of Arisaema leschenaultii (Blume) using leaf explants

V. Vijayan, K. K. Vijayakumar, S. Nigesh — Wed, 06 Mar 2024 00:00:00 +0530

A standard in vitro regeneration protocol from leaf explants was developed for a potential medicinal plant Arisaema leschenaultii. Maximum callus induction (78%) was achieved on MS medium fortified with BAP (1.5 mg/L) and NAA (0.9 mg/L). The maximum percentage of shoot proliferation (75%) was attained on MS medium supplemented with 2.0 mg/L of BAP and 0.5 mg/L of GA₃. The highest root induction (70%) was achieved on MS medium prepared with the combination of NAA (1.5 mg/L) and IBA (0.6 mg/L). The well-rooted plantlets that successfully followed acclimatization in the green house survived. The present efficient and optimized protocol provides mass propagation as well as the possibility of germplasm conservation for this study species.

An Inhibition of proliferation of human osteosarcoma cell line (MG63) by ajwain (Trachyspermum ammi L.) plant extract

B. Anusha, V. M. Datta Darshan, B. Andallu — Mon, 18 Mar 2024 00:00:00 +0530

Trachyspermum ammi L. (TA), popularly called ajwain, is a well-known spice plant, with fruit pods that are used in Indian traditional medicine. Fruits of this plant were scientifically investigated for medicinal properties, but no studies are reported on the vegetative parts of the plant. Hence, the present investigation is aimed to evaluate the aerial parts of the plant for anti-proliferative and antioxidant effects. Methanolic extract (Me) of TA was subjected to sequential fractionation using the solvents in the increasing order of polarity viz. hexane (He), dichloromethane (Dcm), ethyl acetate (Ea), n-butanol (n-Bu), and water (Aq). Phytochemical analyses, DPPH radical scavenging assay, and in vitro antiproliferative activity on the MG63 osteosarcoma cell line (MTT assay) were performed. Preliminary phytochemical analyses revealed the presence of reducing and non-reducing sugars, amino acids, tannins, phenols, terpenoids, and saponins. Ethyl acetate fraction showed the highest amount of total phenolics (367.90±0.02), followed by n-Bu (287.50±0.04), Dcm (193.56±0.07), Me extract (190.14±0.07), Aq (142.20±0.02) and He (80.74±0.01) fractions. Ethyl acetate fraction exhibited higher DPPH radical scavenging activity (IC₅₀ =116.74 μg/mL) followed by n-Bu (IC₅₀=133.81 μg/mL) fraction with a correlation to the higher amount of phenolics and flavonoids. However, maximum antiproliferative activity was exhibited by hexane fraction on MG 63 human osteosarcoma cell line which can be attributed to the presence of thymol, a monoterpenoid phenol present in ajwain. The current study indicates that the aerial parts of T. ammi Linn. can be considered as potential antioxidants and therapeutic against osteosarcoma.

Antigenotoxic potential of the aqueous basidiocarp extracts of Calocybe indica

A. S. Deepthi, Nisha Joseph, A. G. Annakutty — Wed, 27 Mar 2024 00:00:00 +0530

Calocybe indica, commonly known as the milky white mushroom, is an edible mushroom native to India. The antigenotoxic potential of the aqueous basidiocarp extract (25 g/L and 50 g/L) of C. indica was investigated using the Allium cepa test system. Meristematic cells of root tips treated with 100% Coca-Cola served as a positive control. A significant reduction in the mitotic index (7.83 ± 0.60) was observed in the positive control (100% Coca-Cola) compared to the negative control. The highest percentage (65.25 ± 4.58) of chromosomal abnormalities was observed in the positive control. Chromosomal abnormalities were significantly reduced in root tip cells treated with Coca-Cola followed by treatment with basidiocarp extracts such as 25 g/L and 50 g/L (30.32 ± 4.44 and 14.20 ± 2.41, respectively). Coca-Cola induced chromosomal abnormalities were reduced by treatment with basidiocarp extracts, demonstrating the antimutagenic potential of C. indica. The present study indicates that the aqueous basidiocarp extracts of C. indica have anti-genotoxic effects. The clastogenic abnormalities caused by Coca-Cola are competently restored in the root meristem cells of A. cepa treated with the extract.

Occurrence of guggulsterone content based chemotypes in Commiphora wightii

Inamul Haque, Kunal Mukhopadhyay — Sat, 20 Apr 2024 00:00:00 +0530

Commiphora wightii is a critically endangered plant endemic in the arid and semi-arid regions of India. Oleogum is produced by the plant schizogenously. Upon making an incision, this gum exudes from the wound and solidifies in the arid environment. This solidfied gum-resin called ‘gum guggul or guggal’ is mentioned in Ayurvedic, Unani and Siddha literature for the treatment of many ailments. The steroidal ketones, E- and Z- guggulsterone are believed to be the active principles responsible for the medicinal properties. These resin samples were collected from plants in a few regions of Rajasthan, India, for quantitation of guggulsterone content using HPLC. Based on the quantitation of the guggulsterone content, we were able to identify three chemotypes. The first and the most common chemotype showed relatively much higher Z-guggulsterone than E-guggulsterone, the second type showed the absence of E-guggulsterone, the third and rare type showed the presence of equal amounts E- and Z-guggulsterone.

Foliar epidermal micromorphology of genus Glochidion J.R.Forst. & G.Forst. (Phyllanthaceae) by using light and electron microscopy

Priyanka Brahma, Sanjib Baruah — Tue, 23 Apr 2024 00:00:00 +0530

The present study was conducted to compare both qualitative and quantitative characteristics of foliar epidermal micromorphology on some members of Glochidion in Assam. As taxonomic attributes, the foliar epidermal micromorphology study of nine taxa of both abaxial and adaxial surfaces was performed by using light microscopy (LM) and field emission scanning electron microscopy (FESEM). The result showed both amphistomatic and hypostomatic types of leaf surfaces. On the same surface of the leaf, multiple types of stomata were observed such as anomocytic, anisocytic, hemiparacytic, and paracytic types. Significant diversity and variations were observed in stomatal number, size, area, epidermal cell number, subsidiary cells, and trichomes. The stomatal index, stomatal shape, epidermal cell shape, length and width of the stomata, and trichomes showed variation among the studied taxa. Glands were absent in all studied members. Papillae and epicuticular wax crystals were observed in some taxa. In addition, a taxonomic key was also provided based on foliar leaf epidermal characteristics using qualitative and quantitative data from LM and FESEM. Based on quantitative data of foliar leaf micromorphology, principal component analysis (PCA) and cluster analysis were carried out to authenticate the micromorphological data. These would aid in the identification of taxa as well as in taxonomic delimitation.