This paper presents some efficient classes of estimators of population mean on current occasion in the presence of random non-response under a two-phase successive sampling set-up. The suggested classes of estimators are proposed for simple random sampling under various situations of non-response. The properties of proposed estimators have been discussed up to first order of approximation. The efficiency of the presented estimators has been contrasted with the estimators for the complete response scenarios. Two real and two artificially generated data sets are used. The efficacy of the proposed classes of estimators over the existing estimators is checked theoretically and empirically. The numerical comparison supports the proposed estimators.

The genus Bidens a member of family Compositae, is widely documented as an ethno-medicinally important genus of plants. In the present study, anticancer potential of three ethno-medicinally important species i.e., B. bipinnata, B. biternata and B. pilosa were tested. For in-vitro evaluation, an MTT (Thiazolyl blue tetrazolium bromide) assay was performed against cervical cancer cells (HeLa), hepatocellular carcinoma (HepG), and adenocarcinoma human alveolar basal epithelial cells (A549). For in vivo evaluation, Artemia salina, Danio rerio, and Caenorhabditis elegans were used. Among all the tested extracts, the ethanol extract of B. biternata appeared to have highest anticancer activity, and the compounds responsible for this activity were identified to be Tris (2,4-di-tert-butylphenyl), 4-hydroxy-2,4′-dimethoxychalcone, and 2,4-di-tert-butylphenol. This is the first report of the isolation of Tris (2,4-di-tert-butylphenyl) phosphate from the genus Bidens and the first report of 4-hydroxy-2,4′-dimethoxychalcone and 2,4-di-tert-butylphenol from B. biternata. Among the isolated compounds, 4-hydroxy-2,4′-dimethoxychalcone showed the highest anticancer activity with an LD50 value of 236.7 µg/mL. Therefore, this compound carries promising potential for being established as a pharmaceutical for chemoprevention and chemotherapy.

The improved classes of difference-type estimators of finite population median by using auxiliary information in simple random sampling and two-phase sampling have been proposed. The expressions for bias and mean square error are derived up to first order of approximation. Efficiency conditions and numerical comparisons reveal that the proposed class of estimators performs better than the other estimators under same scenario. Using fixed cost the optimum values are obtained for the two-phase sampling scheme.

Ethnopharmacological approaches provide clues for the search of bioactive compounds. Dryopteris ramosa (Hope) C. Chr. (plant family: Dryopteridaceae) is an ethnomedicinal plant of the Galliyat region of Pakistan. The aqueous fraction (AqF) of D. ramosa is being used by inhabitants of the Galliyat region of Pakistan to treat their gastrointestinal tract ailments, especially those caused by bacteria. The aims of the present study were as follows: (i) to justify the ethnomedicinal uses of the AqF of D. ramosa; (ii) to isolate a bioactive compound from the AqF of D. ramosa; and (iii) to evaluate the antibacterial and cytotoxic potential of the isolated compound. Column chromatography (CC) techniques were used for the isolation studies. Spectroscopic techniques (UV–Vis, MS, 1&2D NMR) were used for structural elucidation. The agar-well diffusion method was used to evaluate the antibacterial potential of “i3CβDGP” against five bacterial strains, and compare it with the known antibiotic “Cefixime”. The brine shrimp lethality test (BSLT) was used for cytotoxic studies. The AqF of D. ramosa afforded “iriflophenone-3-C-β-D glucopyranoside (i3CβDGP)” when subjected to LH20 Sephadex, followed by MPLC silica gel₆₀, and purified by preparative TLC. The “i3CβDGP” showed a strong potential (MIC = 31.1 ± 7.2, 62.5 ± 7.2, and 62.5 ± 7.2 µg/mL) against Klebsiella pneumoniae, Staphylococcus aureus, and Escherichia coli, respectively. On the other hand, the least antibacterial potential was shown by “i3CβDGP” (MIC = 125 ± 7.2 µg/mL), against Bacillus subtilis, in comparison to Cefixime (MIC = 62.5 ± 7.2 µg/mL). The cytotoxicity of “i3CβDGP” was significantly low (LD₅₀ = 10.037 ± 2.8 µg/mL) against Artemia salina nauplii. This study not only justified the ethnomedicinal use of D. ramosa, but also highlighted the importance of ethnomedicinal knowledge. Further studies on AqF and other fractions of D. ramosa are in progress.

Gui Zhen Cao is an herbal formulation that has been documented in Chinese traditional medicine as a remedy for diarrhea, dysentery, inflammation, and toxicity. The sources of this formulation (Bidens pilosa L., Bidens biternata (Lour.) Merr. & Sherff, Bidens bipinnata L.) are also listed in ethnomedicinal reports all over the world. In this study, all these plants are tested for in vitro anticandida activity. A quantitative evaluation of the phytochemicals in all these plants indicated that their vegetative parts are rich in tannins, saponins, oxalates, cyanogenic glycoside and lipids; moreover, the roots have high percentages of alkaloids, flavonoids, and phenols. The results indicated significant anticandida activity, especially for the hexane extract of B. bipinnata leaves which inhibited C. albicans (42.54%), C. glabrata (46.98%), C. tropicalis (50.89%), C. krusei (40.56%), and C. orthopsilosis (50.24%). The extract was subjected to silica gel chromatography and 220 fractions were obtained. Purification by High Performance Liquid Chromatography with Diode-Array Detection (HPLC–DAD) and Gas Chromatography tandem Mass Spectrometry (GC-MS/MS) analysis led to the identification of two anticandida compounds: dehydroabietic and linoleic acid having an inhibition of 85 and 92%, respectively.

Xanthones C-glycosides are plants secondary metabolites with diverse biological activities. Among the C-glycoside xanthones, the mangiferin (MF) is of widespread occurrence in plants while isomangiferin (IsoMF) is not very common. For the present study mangiferin (MF) and isomangiferin (IsoMF) were isolated from Dryopteris ramosa. The antibacterial potential of MF and IsoMF was evaluated by using agar well diffusion method while cytotoxic properties of MF and IsoMF were assessed by brine shrimp lethality test (BSLT). The antibacterial potential of MF and IsoMF increases in dose dependent manner. The minimum inhibitory concentration (MIC) indicated strong antibacterial potential of MF against Salmonella setubal (125 µg/mL) and Bacillus subtilis (125 µg/mL) while MF showed weak antibacterial potential against Escherichia coli (500 µg/mL). On the other hand the IsoMF showed better antibacterial potential against all the tested strain including Escherichia coli (MIC = 250 µg/mL). The MF and IsoMF showed poor cytotoxicity towards Brine shrimp nauplii as indicated by their LD₅₀ (969.77 ± 0.67 and 768.92 ± 0.81 µg/mL respectively). The present study has highlighted the antibacterial potential of MF and IsoMF. Further evaluation of these two isomeric compounds may prove to be the future remedies for various bacterial infections and other human ailments.