Antioxidant and anti-inflammatory effects of fractions from ripe fruits of Solanum lycocarpum St. Hil. (Solanaceae) and putative identification of bioactive compounds by GC-MS and LC-DAD-MS.

Brazilian biodiversity includes species of the genus Solanum that have several biological activities, in addition to their relevance to agriculture, economics and popular medicine. The ripe fruits of Solanum lycocapum are an important nutritional food source, since they have levels of vitamin C, total soluble sugars, sucrose, phosphorus, and iron comparable or exceed the levels present in fruits such as pineapples, bananas, oranges, and mangoes. The pulp of the fruit is consumed by the population, and it is also used to produce jellies; to make marmalade, replacing the quince, and it can also be mixed with peaches in the preparation of peach. The objective of this study was to evaluate the anti-inflammatory and antioxidant activities of fractions obtained from the ripe fruits and to identify the constituents with these biological properties. The ripe fruits were collected, dried, crushed, and subjected to extraction by exhaustive percolation, obtaining an ethanol extract that was partitioned with solvents of increasing polarities, obtaining hexane (HEX), ethyl acetate (AC), and hydroethanol (HE) fractions. The AC fraction showed higher antioxidant potential compared to BHT (2,6-di-tert-butyl-4-methylphenol) and similar activity to AA (ascorbic acid) by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical assay, while HEX and HE fractions exhibited of IC50 values similar to BHT. The AC fraction also presented similar activity to BHT by FRAP (Ferric Reducing Antioxidant Power) test. Intraperitoneal treatment with HEX (100 and 300 mg/kg) and HE (100 mg/kg) fractions caused significant inhibition of paw edema induced by carrageenan, 4 and 6 h after the inflammatory stimuli. When analyzed by GC-MS, fatty acids, phytosterols, and triterpenoid were identified in the HEX fraction, whilst 31 compounds were annotated in the AC and HE fractions analyzed by LC-DAD-MS, being phenylpropanoid derivatives, chlorogenic acids, and steroidal glycoalkaloids. The ripe fruits of S. lycocarpum have antioxidant and anti-inflammatory activities, and the detected chemical compounds, especially caffeoylquinic acid derivatives, spermidine, stigmasterol, and ß-sitosterol, may be correlated with these activities. The ripe fruits of this species can be a food alternative rich in bioactive compounds and with benefits for human health.

Allelopathic effect of the ethanol extract and fractions of the aerial parts of Lippia alba (Verbenaceae).

Lippia alba, belonging to the Verbenaceae family, is one of the most commonly utilized medicinal plants in folk medicine. The allelopathic activity was assessed using seeds of Lactuca sativa (lettuce) and Allium cepa (onion) by assessing the growth of the radicle and hypocotyl. The tests showed allelopathic efficiency in inhibiting the growth of lettuce and onion seeds. The best results for allelopathic activity were presented by the dichloromethane (DCM) fraction of the fresh plant, which inhibited radicle (23.04-100% lettuce and 64.17-66.36% onion) and hypocotyl (16.77-100% lettuce and 65.10-69.43% onion) formation, and as well as the DCM fraction of the dry plant, which also inhibited radicle (30.74-82.83% lettuce and 63.50-93.67% onion) and hypocotyl (24.12-70% lettuce and 69.07-79.95% onion) formation. Based on these results, it was found that the aerial parts of L. alba are rich in bioactive substances, suggesting the possibility of using of L. alba as a natural herbicide.

Chemical composition, antioxidant and cytotoxic activities of extracts from the leaves of Smilax brasiliensis Sprengel (Smilacaceae).

The antioxidant and cytotoxic activities of petroleum ether and methanol extracts, fatty acids and methyl esters from leaves of Smilax brasiliensis were evaluated, and the composition of the extracts was determined. Palmitic, linoleic and linolenic acids were major components of the extracts. For antioxidant activity, all samples exhibited IC50 values lower than BHT (2,6-di-tert-butyl-4-methylphenol). The extracts, fatty acids and methyl esters from S. brasiliensis presented no toxicity to larvae of the brine shrimp, Artemia salina. Among the purified substances, only methyl linolenate showed toxicity (LD50 = 21.47 µg/mL). This study showed, for the first time, the composition of petroleum ether and methanol extracts from S. brasiliensis leaves, as well as the antioxidant and cytotoxic activities of extracts, fatty acids and methyl esters.