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Actinomycetes and fungi were successfully isolated from both New Zealand and Malaysian marine invertebrates and classified as facultatively marine based on their ability to grow on both sea water and non-sea water media. Most of the extracts obtained from selected isolates were cytotoxic. A clear preference of the actinomycetes for solid-state fermentation was observed, however, for fungi no significant preference was seen. Three isolates of Streptomyces spp., four Penicillium spp. and two Paecilomyces spp. whose extracts showed good cytotoxicity were selected for further investigation. A small-scale extract obtained from a solid culture of Streptomyces sp. (LA3L2) showed good cytotoxicity and a new cytotoxic metabolite was isolated from a large-scale extract of Streptomyces sp. (LA3L2). This metabolite was characterized as S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15) and is only the third compound reported to contain the S-methyl benzothioate group. Two known compounds, montagnetol (5.16) and erythrin (5.18), were isolated from a further large-scale cultivation of Streptomyces sp. (LA3L2) and is the first reported actinomycete to produce these lichen-related compounds. In addition, two known inactive metabolites (bohemamine (5.1) and bohemamine B (5.2)) were identified from the small-scale extract. Streptomyces sp. (LA3L2) was also investigated for the effect of temperature and salinity on growth and cytotoxicity and shown to produce bohemamine only at 20 - 28℃ and 4% sea salt concentration on solid media. This isolate gave a low yield of active metabolite under all conditions. Small-scale extracts of two other Streptomyces spp. yielded three known cytotoxic metabolites. These were thiazostatin B (7.14) from Streptomyces sp. (LA5L4) and chromomycin A2 (7.1), chromomycin A3 (7.2) and chromomycin 02-3D (7.3) from Streptomyces sp. (LA3L1). All four Penicillium spp. produced known metabolites. Penicillium sp. (LY1L5) yielded two known metabolites, cycloaspeptide A (7.4) and α-cyclopiazonic acid (7.5). α-Cyclopiazonic acid (7.5) and three other known metabolites (roquefortine A (7.6), cyclopeptin (7.7) and viridicatin (7.8)) were isolated from Penicillum sp. (KK3T23). Penicillium sp. (KK3T8) produced brefeldin A (7.10), while mycophenolic acid (7.12) and brevianamide A (7.11) were produced by Penicillium sp. (KK4T14b). The effect of salinity on growth and cytotoxicity was investigated for the two Penicillium isolates producing the cytotoxic metabolite, α-cyclopiazonic acid (7.5). Saline conditions were not required for growth but metabolite production differed between the two isolates with respect to salinity. Isolate LY1L5 required saline conditions for α-cyclopiazonic production whereas isolate KK3T23 produced the metabolite under non-saline conditions and in concentrations of sea salt up to 6%. Three known compounds, indole-3-carboxylic acid (7.15), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16) were identified from Paecilomyces sp. (PR5L9). Investigation of a small-scale extract obtained from a solid culture of another Paecilomyces sp. (PR10T2) resulted in the isolation and characterization of a unique structure of a symmetrical cyclic depsipeptide, epi-angolide (NAM 6-1). NAM 6-1 was considered as a new compound based on four homoisomeric configurations (A1, A2, A3 and A4). The value of dereplication procedures with respect to the rapid identification of metabolites and enhancement of in-house metabolite libraries is discussed. Structural elucidation of nine known metabolites (7.1, 7.2, 7.3, 7.5, 7.6, 7.7, 7.8, 7.10 and 7.11) was greatly aided by the in-house dereplication techniques using LC-MS-UV and AntiMarin database. A significant advantage was gained by the use of the CapNMR which enabled NMR characterization of very small quantities of metabolites (<20 µg). Approximately <5 µg of materials were required to perform 1D proton NMR experiments for the dereplication of seven known compounds; bohemamine (5.1), bohemamine B (5.2), thiazostatin B (7.14), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16). Approximately 20 µg of materials were needed to acquire 1D and 2D (HSQC, HMBC and NOE) NMR spectra for structural elucidation of the new metabolite, S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15). Some 8 µg of materials were sufficient to perform 1D and 2D (COSY, HSQC and HMBC) NMR experiments for complete structural characterization of two known metabolites, montagnetol (5.16) and erythrin (5.18). Approximately 10 µg of materials were needed to acquire 1D and 2D NMR (COSY, HSQC and HMBC) experiments for structural elucidation of the new compound, epi-angolide NAM 6-1 (A1, A2, A3 and A4). Rapid identification of known fungal metabolites enabled the in-house HPLC-UV/Rt library to be enhanced by eight metabolites (7.5, 7.6, 7.7, 7.8, 7.10, 7.11, 7.17 and 7.16). An HPLC-UV/Rt library for actinomycete metabolites was successfully established with the insertion of eight known metabolites (5.1, 5.2, 5.16, 5.18, 7.1, 7.2, 7.3 and 7.14).

Actinomycetes and fungi were successfully isolated from both New Zealand and Malaysian marine invertebrates and classified as facultatively marine based on their ability to grow on both sea water and non-sea water media. Most of the extracts obtained from selected isolates were cytotoxic. A clear preference of the actinomycetes for solid-state fermentation was observed, however, for fungi no significant preference was seen. Three isolates of Streptomyces spp., four Penicillium spp. and two Paecilomyces spp. whose extracts showed good cytotoxicity were selected for further investigation. A small-scale extract obtained from a solid culture of Streptomyces sp. (LA3L2) showed good cytotoxicity and a new cytotoxic metabolite was isolated from a large-scale extract of Streptomyces sp. (LA3L2). This metabolite was characterized as S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15) and is only the third compound reported to contain the S-methyl benzothioate group. Two known compounds, montagnetol (5.16) and erythrin (5.18), were isolated from a further large-scale cultivation of Streptomyces sp. (LA3L2) and is the first reported actinomycete to produce these lichen-related compounds. In addition, two known inactive metabolites (bohemamine (5.1) and bohemamine B (5.2)) were identified from the small-scale extract. Streptomyces sp. (LA3L2) was also investigated for the effect of temperature and salinity on growth and cytotoxicity and shown to produce bohemamine only at 20 - 28℃ and 4% sea salt concentration on solid media. This isolate gave a low yield of active metabolite under all conditions. Small-scale extracts of two other Streptomyces spp. yielded three known cytotoxic metabolites. These were thiazostatin B (7.14) from Streptomyces sp. (LA5L4) and chromomycin A2 (7.1), chromomycin A3 (7.2) and chromomycin 02-3D (7.3) from Streptomyces sp. (LA3L1). All four Penicillium spp. produced known metabolites. Penicillium sp. (LY1L5) yielded two known metabolites, cycloaspeptide A (7.4) and α-cyclopiazonic acid (7.5). α-Cyclopiazonic acid (7.5) and three other known metabolites (roquefortine A (7.6), cyclopeptin (7.7) and viridicatin (7.8)) were isolated from Penicillum sp. (KK3T23). Penicillium sp. (KK3T8) produced brefeldin A (7.10), while mycophenolic acid (7.12) and brevianamide A (7.11) were produced by Penicillium sp. (KK4T14b). The effect of salinity on growth and cytotoxicity was investigated for the two Penicillium isolates producing the cytotoxic metabolite, α-cyclopiazonic acid (7.5). Saline conditions were not required for growth but metabolite production differed between the two isolates with respect to salinity. Isolate LY1L5 required saline conditions for α-cyclopiazonic production whereas isolate KK3T23 produced the metabolite under non-saline conditions and in concentrations of sea salt up to 6%. Three known compounds, indole-3-carboxylic acid (7.15), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16) were identified from Paecilomyces sp. (PR5L9). Investigation of a small-scale extract obtained from a solid culture of another Paecilomyces sp. (PR10T2) resulted in the isolation and characterization of a unique structure of a symmetrical cyclic depsipeptide, epi-angolide (NAM 6-1). NAM 6-1 was considered as a new compound based on four homoisomeric configurations (A1, A2, A3 and A4). The value of dereplication procedures with respect to the rapid identification of metabolites and enhancement of in-house metabolite libraries is discussed. Structural elucidation of nine known metabolites (7.1, 7.2, 7.3, 7.5, 7.6, 7.7, 7.8, 7.10 and 7.11) was greatly aided by the in-house dereplication techniques using LC-MS-UV and AntiMarin database. A significant advantage was gained by the use of the CapNMR which enabled NMR characterization of very small quantities of metabolites (<20 µg). Approximately <5 µg of materials were required to perform 1D proton NMR experiments for the dereplication of seven known compounds; bohemamine (5.1), bohemamine B (5.2), thiazostatin B (7.14), indole-3-carboxylate (7.17) and 5-carboxymellein (7.16). Approximately 20 µg of materials were needed to acquire 1D and 2D (HSQC, HMBC and NOE) NMR spectra for structural elucidation of the new metabolite, S-methyl 2,4-dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (5.15). Some 8 µg of materials were sufficient to perform 1D and 2D (COSY, HSQC and HMBC) NMR experiments for complete structural characterization of two known metabolites, montagnetol (5.16) and erythrin (5.18). Approximately 10 µg of materials were needed to acquire 1D and 2D NMR (COSY, HSQC and HMBC) experiments for structural elucidation of the new compound, epi-angolide NAM 6-1 (A1, A2, A3 and A4). Rapid identification of known fungal metabolites enabled the in-house HPLC-UV/Rt library to be enhanced by eight metabolites (7.5, 7.6, 7.7, 7.8, 7.10, 7.11, 7.17 and 7.16). An HPLC-UV/Rt library for actinomycete metabolites was successfully established with the insertion of eight known metabolites (5.1, 5.2, 5.16, 5.18, 7.1, 7.2, 7.3 and 7.14).

Soils in irrigated fields are impacted by irrigation water quality. Salts in the irrigation water may accumulate in the soil depending on amount of leaching, the quality of water and type of ions present. Salinity is an environmental hazard that is known to limit agriculture worldwide. The quality of irrigation water is thus of concern to agriculturists. More so is the impact it has on productivity. The objective of this study was to quantify the impact due to use of ground water of such quality, with respect to salinity, as found in Berambadi watershed of Southern India, under farmers‟ field conditions. Turmeric (Curcuma Longa L.) was used for the study, based on salt sensitivity, under furrow irrigation. Study sites were selected basing on quality of water, with respect to salinity, crop and irrigation method. Samples of both soil and water were collected from each site and analyzed in the laboratory. The samples were analysed for salinity, alkalinity, pH and Cations of Magnesium, Sodium, Calcium and potassium as well as Chlorides and Sulfates. In addition soil was analysed for texture and Organic matter content. Non destructive plant monitoring for Leaf area (Index), number of leaves and plant height was done up to 210 days from planting. Profile, up to 80 cm depth, soil moisture was monitored at six plots using TDR and surface, up to 6cm depth, soil moisture for all the plots using Theta probe. Potential yield was obtained using STICS 6.9 crop model while field yield was estimated from rhizomes average weight of three plants. For both potential and observed yield estimation, a plant density of 9 plants per M2 was used. The quality parameters in water were correlated to soil parameters and to crop growth and ultimate yield. Impact due to salinity was then identified and quantified using relative yield. Identified quality problems in terms of turmeric response were, salinity, alkalinity and pH there was significant positive correlation between irrigation water salinity and soil salinity. Some wide scatter was observed and could be indicative of irrigation management practices, soil texture difference and other local variations. Observed turmeric yield was significantly negatively correlated to soil salinity. There was a monotonically increasing gap between simulated and observed yield as salinity increased. The maximum observed yield was 71% of the potential. The highest impact due to salinity was observed at 2.1 dS/m amounting to 44 % yield reduction. Excessive chlorosis due to iron deficiency occurred at 24.5% as CaCO3 and pH 7.5. Irrigation water pH was normal as per the guidelines. Soil pH was not so varied; it ranged between 7.1-7.9 except for one site where it was 6. Within the 7.1-7.9 range there was no effect on crop and yield observed. Interaction of stress factors observed was between salinity and alkalinity. The other was rhizome rot disease. Loss of yield to salinity was significant but farmers have no specific plans to leach out salts nor do they have an idea that ground water quality can actually negatively impact productivity. Salinity in irrigation water was in the moderately saline range. While that in the soil was low to slightly saline but could increase given the management practices.