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In systemic therapy, chemotherapeutic drugs, often, cause considerable side effects; and combination of natural compounds lessen the extent of such effects. In the present study, combined effect of citral and 5-fluorouracil was studied in Schizosaccharomyces pombe cells. The antagonistic combination index found was at 0.01 and 0.025 mM of citral with 40 μg or higher concentration of 5-fluorouracil. The combined treatment was so effective that higher number of cells underwent apoptosis compared to individual treatment of 5-fluorouracil. Citral controlled ROS levels and increased survival of normal cells. Several differentially expressed proteins observed in the citral treatment could further help understanding its mechanism of action.

A 10 kD elicitor protein (infestin) produced by Phytopthora infestans was purified and its efficacy for induction of systemic resistance in resistant and susceptible varieties of Solanum tuberosum was studied. Culture filtrates from P. infestans with and without purified elicitor (infestin) were used as elicitors to understand the effect of purified elicitor (infestin) on development of systemic resistance. Culture filtrate and purified elicitor (infestin) were found to induce hypersensitive reaction on the leaves of resistant varieties, but not on susceptible varieties after 48 h. Culture filtrate devoid of purified elicitor (infestin) did not induce any necrotic spots even on resistant variety. Purified elicitor (infestin) was found to induce glucose oxidase, NADPH oxidase, superoxide dismutase, glutathione reductase, catalase and peroxidase enzymes in resistant S. tuberosum plants, however the induction of these enzymes was low in susceptible varieties. The oxidative enzymes were found to induce earlier than antioxidative enzymes and there was negative correlation between these two groups of enzymes. Levels of salicylic acid, phenylalanine ammonia lyase (PAL), beta-1, 3 glucanase and chitinase activities were also found higher in resistant than in susceptible varieties. It was observed that purified elicitor (infestin) was superior to crude culture filtrate, but was not capable of inducing systemic resistance in susceptible varieties.

Culture filtrate of Lasiodiplodia theobromae increased respiration rate, phenylalanine ammonia lyase activity, and levels of hydrogen peroxide, lipid peroxides and salicylic acid in B. nigra plants. Salicylic acid (SA) level increased for 1 hr of interaction and reduced later. Development of systemic acquired resistance (SAR) was found restricted in plants infected with L. theobromae due to deficiency of SA, which is a major signal for development of SAR. Exogenously supplied SA did develop resistance and plant death was delayed. It was hypothesized that deficiency of SA could be due to jasmonic acid produced by fungus that inhibits SA biosynthesis.

Adult albino rats of Wistar strain of 200 to 250 g body weight were lesioned at nucleus accumbens either in the shell area or in core area. The rats were offered 0.2% saccharine solution or 12% sucrose solution or water for drinking. During the prelesion period, rats consumed more of saccharine followed by sucrose and water. The lesion of core area increased the consumption of both the sweet taste solutions but did not affect the water intake. Lesioning of shell area caused an increase in water and sucrose intake whereas saccharine intake remained unaffected. The results suggest that the core area of nucleus accumbens subserves taste induced ingestion and the shell area mediates the effect of nutritional value of food.

Feces of ventromedial hypothalamus (VMH) lesioned obese and sham operated (SL) rats were separately pooled and subjected to column chromatography using sephadex G-150. Fractions showing peak absorption at 280 nm, obtained from respective group of rats were separately pooled and divided into 9 equal aliquots and injected ip in two groups of overnight fasted normal rats (OFN rats). Rats injected with fecal extract from VMH lesioned rats showed decreased food and water intake which was not seen in rats treated with the fecal extract from SL rats suggesting the possible presence of an anorexigenic substance in the feces of VMH lesioned rats but absent in SL rats.