Antifungal activity against the pathogen, Botrytis cinerea, and a bioassay organism, Cladosporium cladosporioides, declined with advancing strawberry fruit maturity as shown by thin layer chromatography (TLC) bioassays. Preformed antifungal activity was also present in flower tissue. The fall in fruit antifungal compounds was correlated with a decline in natural disease resistance (NDR) against B. cinerea in-planta. Crude extracts of green stage I fruit (7 days after anthesis) contained at least two preformed antifungal compounds (R f = 0.44 and 0.37) that were not present in white and red stage fruit. These compounds were shown with TLC reagent sprays to be neither phenolics nor alkaloids. Positive reactions to Ehrlich's reagent suggested that R f = 0.37 was a terpene. Most antifungal activity was found in the achenes of green stage I fruit. However, antifungal activity was found in all tissue types (viz. pith, cortex, epidermis) of green stage I fruit. TLC bioassays revealed that all fruit stages yielded antifungal activity at the origin (R f = 0.00). The approximate area of fungal inhibition at the origin in green stage 1 fruit extracts was 1.87-fold and 1.73-fold greater than in white and red stages, respectively. TLC reagent sprays showed that the antifungal compound(s) at origin included phenolics. This

Conidia of Colletotrichum gloeosporioides germinate and form infection hyphae on inoculated, immature mango but remain quiescent until fruit ripening. Antifungal resorcinols have previously been implicated for quiescence of C. gloesoporioides and Alternaria alternata on mango. This study revealed the presence of a mixture of several gallotannins with glycosidic linkages, including 1,2,3,4,6-penta-O-galloyl-b-D-glucopyranose, with significant antifungal activity in the unripe mango fruit peel. Gallotannin antifungal activity was greater in a cultivar resistant (295.8 mm 2 inhibition) to anthracnose than in a susceptible (148.4 mm 2 inhibition) cultivar. In both, the activity decreased with ripening but the decrease was 10% less in the resistant cultivar. Three recorcinols, 5-pentadecylresorcinol, 5-(12-cis-heptadecenyl)resorcinol, AR 21 and another resorcinol derivative were present in the unripe fruit peel and all declined during ripening, more significantly the 5-(12-cis-heptadecenyl)resorcinol and AR 21. Mango latex, when drained out, separates into an oily and aqueous phase. The aqueous phase showed significant chitinase activity and the ability to digest conidia of C. gloeosporioides. The oily phase has previously been reported to contain resorcinols. Draining fruits of latex soon after harvest resulted in greater incidence and severity of anthracnose at ripe stage. Chitinase activity was less in the peel of fruits from which latex was drained. The evidence suggests that the resistance of unripe mango to C. gloeosporioides is because of an elaborate constitutive defence system comprising antifungal resorcinols, gallotannins and chitinases.

Anthracnose caused by Colletotrichum gloeosporioides in ripe avocados originates as latent infections in the immature fruits. Concentrated ether extract of the peel of apparently healthy, immature avocados when bioassayed on thin layer chromatographic plates with conidia of either Cladosporium cladosporioides or C. gloeosporioides produced four inhibition areas at Rf 0.30, 0.32, 0.70 and 0.75 (these were denoted as AvIV, AvIII, AvII and AvI respectively). A hot chloroform extract was partitioned on a silica gel column and the four antifungal compounds were separated. Spectroscopic data revealed that one of these compounds, AvII, was similar to cis‐l‐acetoxy‐2‐hydroxy‐4‐oxo‐heneicosa‐12,15‐diene and another (AvIV) was a long chain saturated compound comprising hydroxyl group(s) having molecular weight of 268. Toxicity of AvII to C. gloeosporioides was 2 times that of AvIV and 6.5 and 7.5 times that of AvIII and AvI respectively. The amounts of these four antifungal compounds increased gradually during fruit development and reached their maxima at harvest. The concentration of AvI, AvII, AvIII and AvIV was 1300, 920, 1050 and 780 μg/g fresh peel respectively in the fruit at harvesting maturity. The amount of AvII and AvIV decreased to 53 and 64 μg/g fresh peel respectively in the fruit at the ripe stage at which neither AvI nor AvIII was detected. This took place in coincidence with the onset of progressive lesion development by the fungus.

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Unripe wood apple fruit is generally free from visible fungal growth before and at harvest but a succession of fungi appears on the fruit shell, and sometimes in the pulp, during ripening. A TLC‐Cladosporium bioassay of the chloroform extract taken from unripe fruit shell demonstrated three inhibition areas. Similar extracts from stem‐bark and root‐bark produced these three, and one additional, inhibition areas. The four compounds responsible for inhibition were identified as psoralene, xanthotoxin, 2,6‐dimethoxybenzoquinone and osthenol. Concentrations of the three antifungal compounds on unripe fruit shell increased during the first 4 days after harvest and then declined. They remained much below those required to inhibit the development of three fungi on TLC plates. Titratable acidity of the unripe fruit pulp was high but decreased by about 50% during ripening. Levels of reducing sugars were very low in the unripe fruit pulp but increased by about five times during ripening. Levels also increased in the fruit shell and its washings. The possible role of these factors in restricting fungal growth in unripe fruits is discussed.

B. cinerea and C. atramentarmTn rotted wound-moculated green tomato frviits and zymes were extracted from the fruit tissue rotted by B. cinerea and C, atramentarium but no pectic enzymes attributable to the fungus were detected in ripe fruits rot-ted by G. cingulata. G. cingulata produced endo-PG and endo-PL in vitro, C. atramentarium produced endo-PL in vitro and in vivo and B. cinerea produced exo-PG in vitro and in green fruits but endo-PG and endo-PL in ripe fruits. Well ripened tomato fruits contained high levels of endogenous PG. All three fungi produced proteolytic enzymes in vitro and in vivo. Proteases produced trypsm-like or diymotrypsin-like in nature, Protease produced by B. cinerea had optimum activity at pH 7 and showed both trypsin and chymotrypsin-like activity.1 roteins extracted irom tiie ceil walls oi tomato iruits iiinibi'ted both the cndo-PG and endo-PL produced by G. cingulata and the endo-PL produced by B. cinerea but did not in-Or txie endogenous PO from toma*to fruits.The cell wall proteins also contained trypsin and chymotrypsm mhibitor activity ^^lluI! inhibited 70 % of the activity of the protease produced by B.cinereay but had little ciK ô u the proteases produced by G. cingniutUj C. atramentaruim or the tomato cndogcnou ]•' ' Enzymes produced m vitro by G. cingulata macerated green tomato tissue moii In' little effect on the rate of maceration by the enzymes produced by C.atuvucw . •" cinerea.U,S, Copyright Clearance Center Code Statement: 003 1-948 l/83/0603-0239;fi;02.50/0

Use of bottled water in Sri Lanka has increased over the last decade, while new brands of bottled water are often introduced to the market. However, the manufacturers' adherence to bottled water regulations is questionable, raising concerns regarding the quality of bottled water. The objective of the current study was to investigate the microbiological and chemical quality of bottled water in Sri Lanka. Thirty bottled water brands were sampled and their chemical and microbiological parameters were analyzed. Microbiological analysis was carried out within 1 to 3, 3 to 6, 6 to 9, and 9 to 12 mo after the date of manufacture. The results indicated that 63% of brands tested exceeded the levels permitted by the Sri Lanka Standards Institution (SLSI) for presumptive total coliforms (TC) (<10 cfu per 100 mL) whereas 97% brands exceeded the World Health Organization (WHO) permitted level. Thirty percent of brands exceeded the limit for presumptive fecal coliforms (FC) (0 cfu per 100 mL in accordance with WHO permitted levels, SLSI and the Sri Lanka Health Ministry requirement). Eighty percent of brands showed higher heterotrophic plate counts (HPC) which exceeded the WHO guidelines for bottled drinking water. Throughout their shelf life, the counts of TC, FC, and HPC bacteria decreased. Bacteria identified were Klebsiella pneumoniae ssp. pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, and Pasteurella haemolytica, the most frequently being P. aeruginosa. The dominant fungi identified were Aspergillus sp. and Penicillium sp. Inorganic chemical parameters were within permitted levels for all brands except for initial content of ammonia. The results of this study show the need for the bottling industry to be monitored closely by relevant authorities, in order to provide safe bottled drinking water to consumers in Sri Lanka.