Preliminary Phytochemical Analysis of Alternanthera sessilis Leaves (Linn). R.Br. ex DC.

Alternanthera sessilis (Linn). R. Br. ex DC. is a treasure house of phytochemicals belongs to family Amaranthaceae, popularly known as stalkless joy weed, sessile joy weed, dwarf copperleaf, joy weed, Garundi, Guroo, Kanchari. The ability of its seeds to germinate in any season of the year makes it a constantly flourishing component of the vegetation. The main objective of current investigation was to study the qualitatively preliminary phytochemical analysis of such weed species. The fresh plant leaves of Alternanthera sessilis were screened to understand the phytochemical potential with the use of four extracts such as aqueous, acetone, methanol and ethanol. The outcome of the study indicates that the fresh plant contains different classes of secondary metabolites such as alkaloids, carbohydrates, cardiac-glycosides, flavonoids, phenols, saponins, tannins, terpenoids, quinones, coumarins etc. Phytochemical are certain non-nutritive plant chemicals which have allelopathic properties. These phytochemical constituents play an important role in formulation of pharmaceutical and pharmacological drugs

Chemosystematic Evaluation of Some Nigerian Gossypium hirsutum L. Using Qualitative and Quantitative Phytochemical Analysis

There is little information on the use of phytochemicals for the systematic study of variation and resolving relatedness in Nigerian Gossypium hirsutum species. Thus, there is a need to carry out detailed phytochemical studies of the plant leaves, which could be helpful in ascertaining their diversity and relatedness. The qualitative and quantitative phytochemical screening was conducted on 18 accessions of G. hirsutum using the established laboratory protocols. The findings of this study indicated the presence of tannin, alkaloids, proline, flavonoids, and saponin in all of the accessions that were grouped into two at 17% genetic distance, indicating 83% relatedness. However, phytosterol, terpenoids and glycosides were absent in three of the accessions, which were grouped at 48%. The phytochemical compositions were tannin (1.30-1.09 mg/100 g), flavonoid (1.60-1.16 mg/100 g, terpenoid (0.42-0.35 mg/100 g), alkaloid (1.47-1.11 mg/100 g), saponin (4.86-1.59 mg/100 g), glycoside (1.02-0.88 mg/100 g), proline (1.57-1.0 mg/100 g) and phytosterol (0.36-0.2 mg/100 g). The aim of this research was to determine the diversity and relatedness of G. hirsutum genotypes collected from different locations of Nigeria. In general, this study emphasises the use of plant chemicals for classification purposes.

Plant chemicals affect trade-offs between adult preference and larval performance of the rice water weevil, Lissorhoptrus oryzophilus

Herbivores use plant chemicals for host-plant selection to maximize their own and/or offspring performance. Since host plants that are optimal for mother and offspring are often different and spatially/temporally separated, how plant chemicals affect trade-offs between adult preference and larval performance remains unclear. We found that adults of the rice water weevil (Lissorhoptrus oryzophilus), one of the most important pests on rice in the world, preferred volatiles from barnyard grass over rice, tended to feed and oviposit on barnyard grass compared with rice. In contrast, larvae performed better on rice roots than on barnyard grass roots. Chemical analysis further show that rice roots had higher nitrogen and soluble sugar but lower lignin and cellhouse contents than barnyard grass. Together, these results suggest that violate, nutritive and defensive chemicals could jointly determine trade-offs of the adult preference and larval performance on these two hosts. As developing chemical-based technology is one of the main approaches for control of pest insects, our findings may also contribute to the future efforts for management of the rice water weevil.

Phytophotodermatitis: A Case Report

A rare phototoxic dermatological reaction seen in Indian Sub-continent, known as Phytophotodermatitis, occurs with exposure to ultraviolet light after contact with certain plant chemicals. Phytophotodermatitis named from the terms ‘phyto’ means plant, ‘photo’ means light, and ‘dermatitis’ means skin inflammation. The signs and symptoms of Phytophotodermatitis typically initiated 24 hours after comes in contact with skin, and the peak is reached between 48 to 72 hours. The indications may be from mild or severe. The signs are redness, tenderness, burning sensation, pain, inflammation, itching, blistering, thickened layer of skin after blisters rupture. The area of blisters is usually asymmetrical in shape. These are seen in the areas of the skin, that were exposed to the chemical. For example, the drip form of blister seen in the skin if it is exposed to fruit juice. If the skin were brushed against a plant, it would show streaks like pattern. Though the early symptoms subside, within 7-14 days, signs of blackening of the skin may show hyperpigmentation. This stage of Phytophotodermatitis is known as post-inflammatory pigmentation and might last for many months. In some cases, the affected person will have a very mild inflammatory reaction, if they are exposed to sunlight, while some may not even know that they experienced a reaction. The hyperpigmentation is the initial sign to know that they have got Phytophotodermatitis. Initial symptoms get aggravated because of wet skin, sweat and heat. Darkening of skin-colour is observed in the persons while they are exposed to sunlight. In this case, we are reporting about a patient having this condition and the cause for the occurrence.

Cytokinin Sensing in Bacteria

Although it has long been known that bacteria detect and react to plant chemicals to establish an interaction, the cellular signaling mechanisms involved in these perception processes have hitherto remained obscure. Some exciting recent advances in the field have described, for the first time, how some phytopathogenic bacteria sense the host plant hormones, cytokinins. These discoveries not only advance the understanding of cell signaling circuitries engaged in cytokinin sensing in non-plant organisms, but also increase our knowledge of the broad role of these ancient molecules in regulating intra- and interspecific communications.